فهرست مطالب

فصلنامه پژوهش های ژئومورفولوژی کمی
سال هفتم شماره 3 (پیاپی 27، زمستان 1397)

  • تاریخ انتشار: 1397/12/22
  • تعداد عناوین: 15
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  • حسن صدوق، محمد مهدی حسین زاده *، خلیل رضایی، ایرج رحمانی، سمیرا چزغه صفحات 1-17
    مخروط افکنه ها یکی از مناسب ترین مناطق برای ایجاد سکونتگاه های شهری هستند بنابراین توسعه پروژه های عمرانی بر سطح آنها اجتناب ناپذیر است. مخروط افکنه های کن و چیتگر در جنوب بلندی های البرز و در شمال غرب تهران قرار گرفته اند و در این پژوهش سعی شده تا رسوبات این بخش از تهران با نگاه سیستمی و با توجه به نوع رسوبات و همچنین فرم و فرایندهایی که مختص این محیط است بررسی و ساختارهای رسوبی آن مانند: گردشدگی، نسبت پهنی، ضریب شکل و کرویت در هر دو مخروط مورد مقایسه و تحلیل قرار گیرند و در نهایت در جنبه کاربردی خود همبستگی بین فاکتورهای رسوبی موثر بر مقاومت خاک آنالیز و مهمترین فاکتور رسوبی تاثیر گذار بر مقاومت خاک تعیین گردد. برای مقایسه شکل و اندازه رسوبات، طی بازدیدهای میدانی تعداد 24 نقطه نمونه برداری از قسمت های بالایی تا انتهایی هر دو مخروط افکنه انتخاب و مختصات آنها با دستگاه GPS ثبت و از هر یک از ترانشه ها بصورت لایه به لایه نمونه برداری انجام گردید. بر پایه بررسی ها و نتایج آزمایشگاهی همچنین تحلیل داده های فوق توسط نرم افزارهای اکسل، گردیستات و فری هند مشخص گردید که مخروط افکنه چیتگر در اندازه دانه از الگوی نمایی کاهش به سمت پایین پیروری می کند درصورتی که در مخروط افکنه کن این الگو تا قسمت میانی روند کاهشی را نشان میدهد ولی در قسمت انتهایی به دلیل تداخل با رسوبات مخروط افکنه کرج این نظم بهم می خورد. مقایسه فرم رسوبات نشان داد که گردشدگی و کرویت دانه ها در هر دو مخروط به دلیل طی مسافت طولانی از بالا به پایین روند افزایشی را نشان می دهد. آنالیز همبستگی بین خصوصیات اندازه و شکل رسوبات با نتایج آزمون نفوذ استاندارد (SPT) ثابت کرد که فاکتور متوسط قطر ذرات و گردشدگی بیشترین همبستگی را در عمق های مختلف با مقاومت خاک دارند که اولی مثبت و مستقیم و دومی منفی و غیر مستقیم است.
    کلیدواژگان: کن، چیتگر، مخروط افکنه، آزمون نفوذ استاندارد
  • شهرام روستایی *، داود مختاری، زهرا اشرفی فینی صفحات 18-30
    امروزه، اینترفرومتری تفاضلی راداری(DInSAR) به عنوان یکی از روش های کارآمد در اندازه گیری جابجایی سطح زمین محسوب میشود. به طوری که با استفاده از این فناوری، امکان پایش حرکات کوچک سطح زمین به صورت پیوسته، با دقت بالا و در گستره وسیعی امکان پذیراست. در این پژوهش، از تکنیک اینترفرومتری تفاضلی بر اساس سری زمانی 29 تصویر راداری سنجنده ASAR ماهواره Envisat در بازه زمانی سال 2003 الی 2009 جهت شناسایی و پایش مناطق ناپایدار حوضه آبریز طالقان استفاده گردید. نتایج حاصله از این تحقیق بر اساس مشاهدات میدانی مورد ارزیابی قرار گرفت. براساس نتایج این تحقیق 17 پهنه ناپایدار در بازه زمانی فوق شناسایی شد که بزرگترین آن ها از نوع لغزش مرکب میناوند با میزان جابجایی 5/2 سانتی متر در این مدت جابجایی داشته است و همچنین کوچکترین پهنه لغزشی به نام لغزش زیدشت از نوع چرخشی با 5/1 سانتی متر در بازه زمانی فوق جابجایی داشته است . انطباق موقعیت مکانی زمین لغزش های شناسایی با برخی مناطق لغزشی قدیمی بیانگر فعالی بودن پهنه های لغزشی پیشین منطقه است. از نظر توزیع مکانی، مناطق لغزشی شناسایی شده عمدتا در مجاورت شبکه زهکشی و مناطق مسکونی حوضه قرار داشته و این امر ضمن اشاره به تاثیر شبکه زهکشی در وقوع ناپایداری دامنه ای، در ارتباط با جابجایی و انتقال مواد گسیخته شده به داخل شبکه هیدروگرافی و افزایش بار رسوبی رودخانه و دریاچه سد طالقان نیز حائز اهمیت است.نتایج به دست آمده در این بازه زمانی حاکی از آن است مناطق ناپایدار در دامنه های غربی با دقت بالائی نسبت به شیب های شرقی آشکارسازی شده اند.میانگین میزان جابجایی محاسبه شده این پهنه های لغزشی در این دوره 6- تا 13 میلی متر می باشد. مهم ترین نقطه لغزشی شناسایی شده در دوره اخیر، توده لغزشی میناوند و زیدشت می باشند که در مجاورت سد طالقان و مناطق مسکونی قرار دارند.
    کلیدواژگان: ناپایداری دامنه ای، اینترفرومتری تفاضلی، تصاویر راداری، حوضه آبریز طالقان
  • رضا علی پور *، امیر حسین صدر، حسین نظری دبیر، سحر قمریان صفحات 31-56
    هدف از این پژوهش ارزیابی شواهد زمین ساختی تاثیرگذار بر ژئومورفولوژی کنونی کوه های گرین با استفاده از شاخص های مورفومتری و تحلیل های فراکتالی می باشد. رودخانه ها و شبکه زهکشی ازجمله مهم ترین عوارضی هستند که نسبت به تغییرات زمین ساختی بسیار حساس می باشند. جهت بررسی تاثیرات گسل نهاوند بر ژئومورفولوژی شبکه زهکشی، ابتدا محدوده مورد مطالعه به 47 حوضه تقسیم گردید. سپس شاخص های کمی مورفومتری از قبیل شاخص گرادیان - طول رودخانه (SL)، شاخص عدم تقارن حوضه زهکشی (Af)، شاخص تقارن توپوگرافی عرضی (T) و شاخص سینوسیتی جبهه کوهستان (Smf) محاسبه شده است. به منظور تعیین میزان فعالیت زمین ساختی نسبی در منطقه مورد مطالعه، شاخص زمین ساخت فعال نسبی (Iat) محاسبه شده است. همچنین بعد فرکتالی در 6 پهنه در منطقه مورد مطالعه برای الگوی گسل ها و شبکه زهکشی منطقه به روش مربع شمار، نمودارهای Log – Log و استفاده از تحلیل های فرکتالی مربوطه محاسبه شده است. نتایج بدست آمده از بررسی شاخص های مورفومتری و ابعاد فرکتالی برای سیستم گسلی فعال و شبکه زهکشی در کوه های گرین نشان دهنده فعالیت بیشتر بخش مرکزی (در راستای کوه گرین) و بخش جنوبی منطقه (پهنه گسل نهاوند) نسبت به دیگر بخش های منطقه می باشد. به طور کلی می توان بیان نمود که ژئومورفولوژی شبکه زهکشی منطقه مورد مطالعه از نیروهای فعال زمین ساختی تاثیر پذیرفته است.
    کلیدواژگان: زمین ساخت، شاخص های مورفومتری، فرکتال، گسل نهاوند، کوه های گرین
  • رضا اسماعیلی *، راضیه یارمحمدیان، قاسم لرستانی صفحات 57-70
    فرسایش کرانه رود اثرات ژئومورفیک متعددی بر کانال رود شامل تخریب کناره رودخانه، تغییر مسیر رود، افزایش ورود رسوبات به جریان، رسوب گذاری در رودخانه و غیره ایجاد نموده و می تواند به عنوان یک مخاطره برای فعالیت های انسانی محسوب گردد. در این مقاله پایداری و ناپایداری کرانه رود با استفاده از روش های ارزیابی سریع ژئومورفیک (RGA) در قسمت هایی از رودخانه سیمره (در شهرستان دره شهر، استان ایلام) مورد بررسی قرار گرفت. رودخانه سیمره در محدوده مورد مطالعه به 13 بازه تقسیم بندی شد و با نقشه برداری از مقاطع عرضی نمونه و عملیات میدانی شاخص های پایداری و ناپایداری کرانه رود ارزیابی شدند. روش شاخص پایداری کانال رود (CSI) و شاخص پتانسیل فرسایش کرانه رود اکلاهما- اوزاراک (OSPEI) برای مطالعه فرسایش کرانه رود مورداستفاده قرار گرفتند. بر اساس روش CSI همه بازه های مورد مطالعه دارای ناپایداری متوسط بوده اند و شاخص های فروسایی بستر، فرسایش کناره، شواهد حرکات توده ای و مدل تکاملی رود مهم ترین عوامل تاثیرگذار در تعیین میزان پایداری و ناپایداری کرانه رود ارزیابی شدند. در روش OSEPI، 86 درصد بازه ها دارای ناپایداری متوسط و 14 درصد بازه ها در حالت ناپایدار ارزیابی شدند. در این روش، شاخص های ارتفاع کرانه، رسوبات منفصل کرانه، شواهد فرسایش کرانه و پوشش گیاهی حاشیه رود به عنوان مهم ترین عوامل در میزان ناپایداری کناره رود تعیین شدند. امتیازات به دست آمده از هر دو روش رابطه مثبت و نسبتا خوبی ( R2 = 0.71) داشته اند. نتایج امتیازدهی شاخص ها و امتیازات نسبی عوامل در ناپایداری کرانه رود نشان می دهد که روش OSEPI شاخص های مناسب تری را ارائه نموده و تقسیم بندی توصیفی آن بهتر از روش CSI قابلیت تفکیک دارد.
    کلیدواژگان: فرسایش کرانه رود، ارزیابی سریع ژئومورفیک، سیمره، ایلام
  • عقیل مددی *، حسن مظفری صفحات 71-90
    شناخت لند فرم های ژئومورفولوژی و بررسی تحولات و تغییرات آن در همه مناطق بخصوص مناطق کوهستانی در جهت مدیریت محیطی در زمینه های مختلف از نیازهای مهم و ضروری علم ژئومورفولوژی است. عوامل دینامیک درونی و بیرونی زمین دائما باعث ایجاد تغییرات در لند فرم های ژئومورفولوژی می شوند. بنابراین شناخت این تحولات و تغییرات جهت مدیریت بهتر در زمینه های مختلف طبیعی و انسانی ضروری است. مناطق کوهستانی به علت صعب العبور بودن مطالعات میدانی را دچار چالش می کنند. علم ژئومورفولوژی نیز همگام با سایر علوم از فناوری های روز دنیا مانند علم سنجش از دور جهت تسریع در پیشبرد اهداف و نیازها استفاده می کند. در همین راستا جهت شناسایی لند فرم های سطحی و مهم حوضه آبریز سجاسرود و بررسی روند تغییرات آن در طول سال های 1986 تا 2018 از تصاویر ماهواره ای لندست TM و OLI استفاده گردید. جهت شناسایی لند فرم ها، ضمن بررسی های میدانی از تصاویر نرم افزار گوگل ارث و نقشه های توپوگرافی کمک گرفته شد. سپس از طریق روش های طبقه بندی نظارت شده حداکثر احتمال، شبکه عصبی و ماشین بردار پشتیبان لند فرم های اصلی استخراج گردید. نتایج ارزیابی دقت طبقه بندی را نشان داد. روش حداکثر احتمال با صحت کلی 70/97 و ضریب کاپای 96 درصد در سال های 1986 و 2018 نسبت به دو روش دیگر عملکرد بهتری در تهیه نقشه ژئومورفولوژی و روند تغییرات دارد. برای بررسی روند تغییرات لند فرم ها و آشکارسازی تغییرات در بازه زمانی 32 ساله از نقشه طبقه بندی حداکثر احتمال و الگوریتم MNF در محیط نرم افزار ENVI استفاده گردید. نتایج نهایی نشان داد، پهنه های پوشش گیاهی و دشت آبرفتی به ترتیب با 159/479 و 26/572 درصد افزایش مساحت داشتند. در مقابل کوه ها و تپه ها، پادگانه های آبرفتی، مخروط افکنه ها و آبرفت های جدید با کاهش مساحت مواجه بودند. همچنین نتایج الگوریتم MNF نشان داد بیشترین شدت و سرعت تغییرات مربوط به دشت های آبرفتی، کوه ها، تپه ها و کمترین سرعت تغییرات مربوط به مخروط افکنه ها است.
    کلیدواژگان: تغییرات لند فرم، الگوریتم های طبقه بندی نظارت شده، الگوریتم MNF، حوضه آبریز سجاسرود
  • حمید بابلی موخر *، کورش شیرانی، علیرضا تقیان صفحات 91-116
    تحلیل ویژگی های فرمی سطح زمین که می تواند متاثر از عوامل اقلیمی، هیدرولوژیکی، خصوصیات ذاتی سازندها و بویژه فعالیت های نئوتکتونیک باشد، نقش مهمی در شناسایی و معرفی مناطق درگیر با خطر زمین لغزش دارد. هدف این تحقیق ارزیابی نقشه پهنه بندی حساسیت زمین لغزش با استفاده از بکارگیری شاخص های ژئومورفومتریک همراه با سایر عوامل مرسوم در پهنه بندی به منظور افزایش درستی نقشه حساسیت پذیری زمین‏لغزش در حوضه آبخیز رودخانه فهلیان می باشد. در این پژوهش از 20 عامل موثر مشتمل بر 14 عامل مرسوم و 6 عامل ژئومورفومتریک به منظور ارزیابی میزان صحت نقشه پهنه بندی حساسیت زمین لغزش استفاده شد. بدین منظور ابتدا نسبت به تعیین وزن طبقات هر یک از عوامل با استفاده از روش فاکتور اطمینان اقدام شد. سپس با استفاده از اوزان بدست آمده و اجرای روش رگرسیون لجستیک نقشه حساسیت پذیری نسبت به زمین‏لغزش با دو رویکرد بدون و با بکارگیری شاخص های ژئومورفومتریک در کنار سایر عوامل تهیه شد. نتایج حاصل از اجرای مدل رگرسیون لجستیک، نشان داد عامل شیب، تراکم پوشش گیاهی، جهت شیب و فاصله از آبراهه به ترتیب بیشترین تاثیر را در رخداد زمین لغزش دارد. در نهایت با استفاده از منحنی ویژگی عملگر نسبی (ROC) اقدام به اعتبارسنجی، ارزیابی و مقایسه نقشه های حاصل از دو رویکرد گردید. سطح زیر منحنی در حالت بدون و با بکارگیری شاخص های ژئومورفومتریک به ترتیب 82/0 و 88/0 می باشد. بنابراین بکارگیری شاخص‏های ژئومورفومتریک منجربه افزایش درستی نقشه پهنه بندی حساسیت نسبت به زمین‏لغزش شدهاست. براساس نتایج حاصل از طبقه‏بندی نقشه پهنه بندی حساسیت نسبت به زمین‏لغزش با استفاده از عوامل ژئومورفومتریک، 78/14درصد (94/59563 هکتار) و 06/17درصد (04/68767 هکتار) از منطقه موردمطالعه به ترتیب در رده حساسیت زیاد و خیلی زیاد قرار گرفته است. باتوجه به نقش بکارگیری شاخص های ژئومورفومتریک در افزایش صحت نقشه حاصل، استفاده از این رویکرد در تهیه نقشه پهنه بندی حساسیت نسبت به زمین‏لغزش پیشنهاد می گردد.
    کلیدواژگان: زمین لغزش، پهنه بندی، ژئومورفومتریک، رگرسیون لجستیک، حوضه آبخیز رودخانه فهلیان
  • امیر صفاری *، مجتبی یمانی، امیر کرم، پریوش کرمی صفحات 117-135
    زمین لغزش به عنوان یک مخاطره طبیعی، همواره خسارات فراوانی را به همراه داشته است. شناسایی عوامل موثر در وقوع این پدیده و پهنه بندی خطرآن ، یکی از روش های اساسی وکاربردی جهت دستیابی به راهکارهای کنترل و پایش آن می باشد. دراین پژوهش هدف بررسی ارتباط تکتونیک فعال و پتانسیل وقوع زمین لغزش درحوضه آبریزجاجرود به عنوان یکی از حوضه های کوهستانی کشور می باشد. ابزارهای اصلی پژوهش را شاخص های مورفوتکتونیکی تشکیل داده اند. این شاخص ها به تفکیک در 39 زیر حوضه جاجرود مورد بررسی قرارگرفته اند. نسبت تعداد زمین لغزش ها به تعداد زیرحوضه ها برای هرطبقه از IAT به دست آمد . پس از آن درجه سطح خطراحتمالی از کلاس های IATشناسایی شد. در نهایت ، خطر زمین لغزش برای هر زیر حوضه بر اساس اثر ترکیبی از سطح خطر احتمالی و فرکانس وقوع زمین لغزش مورد بررسی قرار گرفت . نتایج نشان می دهد که تطابق خوبی بین کلاسIAT و نسبت تعداد زمین لغزش ها به تعداد زیرحوضه ها وجود دارد . حدود 85٪ از زیر حوضه ها که زمین لغزش در آنها رخداده در سطح زیاد و بسیار زیاد خطر قرار دارند ، در حالی که از 27 زیرحوضه بدون زمین لغزش ، حدود 33 درصد در سطوح بالا و بسیار بالای خطر قرار دارند . به منظور صحت سنجی و ارزیابی دقت مدل از دوشاخص به نام های مجموع کیفیت (QS) و دقت روش (P)استفاده شد . مقدار مجموع کیفیت (QS) 97/0 و دقت روش (P) برای کلاس های خطر زیاد و خیلی زیاد 79/0 بدست آمد . مجموع کیفیت و دقت روش نشان دهنده صحت یا مطلوبیت عملکرد روش در پیش بینی خطر زمین لغزش است . یافته ها نشان دادند که حوضه جاجرود از نظرتکتونیکی بسیار فعال بوده و این موضوع استعداد روانگرایی دامنه ای و زمین لغزش را به نسبت افزایش داده است.
    کلیدواژگان: زمین لغزش، مورفوژنتیک، تکتونیک فعال، حوضه جاجرود
  • اسدالله حجازی، شهرام روستایی، مریم رنجبریان شادباد * صفحات 136-150
    بررسی عوامل موثر در وقوع زمین لغزش، تهیه نقشه آسیب پذیری و دوری جستن از مناطق مستعد وقوع زمین لغزش می تواند کمک موثری در کاهش خسارت های احتمالی و مدیریت خطر حاصل از این پدیده داشته باشد. بنابراین هدف تحقیق حاضر ،ارزیابی وپهنه بندی حوضه حاجیلرچای از لحاظ خطر زمین لغزش می باشد. برای بررسی و پهنه بندی خطر زمین لغزش در این حوضه ابتدا نقشه ها و لایه های اطلاعاتی عوامل اصلی موثر در رخداد این پدیده از قبیل شیب، جهت شیب، بارش، لیتولوژی، کاربری اراضی، فاصله از گسل، فاصله از آبراهه و طبقات ارتفاعی در سامانه اطلاعات جغرافیایی (GIS) تهیه گردید و سپس با استفاده از تصاویر ماهواره ای و عملیات میدانی زمین لغزش های موجود در منطقه شناسایی شد. با استفاده از تئوری دمپستر – شفر وزن هر یک از فاکتورها محاسبه شد وزن ها در نقشه های عامل وارد شده و برای هر عامل یک نقشه وزنی به دست می آید. در مرحله بعد نقشه های وزنی با هم جمع شده و در نهایت نقشه پهنه بندی خطر زمین لغزش، در پنج رده با خطر بسیار کم تا بسیار زیاد تهیه گردید. نتایج پژوهش نشان دهنده این است که در حدود 43/9 درصد از مساحت حوضه حاجیلرچای، احتمال وقوع زمین لغزش خیلی زیاد بوده، همچنین 43/22 درصد احتمال وقوع زیاد، 09/28درصد احتمال وقوع متوسط، 33/25 درصد احتمال وقوع کم و در69/14 درصد احتمال وقوع خیلی کم می باشد.
    کلیدواژگان: پهنه بندی زمین لغزش، تئوری احتمالاتی دمپستر-شفر، سامانه اطلاعات جغرافیایی، حوضه حاجیلرچای
  • لیلا گلی مختاری *، سعید نگهبان، نجمه شفیعی صفحات 151-163
    ژئودایورسیتی (تنوع زمین شناختی) یک ویژگی چشم انداز مربوط به ناهمگونی خواص فیزیکی سطح زمین است. همانگونه که در طبیعت و در میان موجودات زنده (گیاه و جانور) گوناگونی و تنوع (بیودایورسیتی) به چشم می خورد، در پدیده ها و عوارض زمین شناختی نیز گوناگونی و تنوع (ژئودایورسیتی) فراوانی وجود دارد. با توجه به این که این گوناگونی در کشوری مانند ایران که در یک نقطه ی پیچیده و پر تنش از دیدگاه فرآیند ها و رویداد های زمین شناختی قرار دارد، میزان بالایی دارد، این پژوهش با هدف تحلیل مقایسه ای ژئودایورسیتی 3 حوضه در زیرحوضه های هندیجان جراحی، واقع در جنوب غرب ایران در شمال غرب استان فارس شکل گرفت. روش پژوهش مبتنی بر روش های تحلیلی و توصیفی است و پس از تهیه لایه های مورفومتریک به روش (TPI) ، مورفوکلیماتیک و زمین شناسی و محاسبه شاخص های تنوع و غنا برای هر گروه این لایه ها تلفیق شدند و نقشه نهایی برای محاسبه شاخص پنجگانه ژئودایورسیتی که شامل تراکم ناهمواری هر قطعه (PRD) ضریب ناهمواری سیمپسون (SIEI) ، ضریب ناهمواری شانون(SHEI) ، ضریب دایورسیتی شانون(SHDI) ، ضریب دایورسیتی سیمپسون(SIDI) و تراکم ناهمواری هاآماده شد. نتایج حاصل از محاسبه شاخص ها نشان داد که در فاکتور زمین شناسی حوضه فهلیان به دلیل تنوع و توسعه سازند بیشترین ارزش را در شاخص ها به خود اختصاص داده اما در فاکتور های مورفومتریک و لایه نهایی بالاترین ارزش مربوط به حوضه نورآباد است که به دلیل داشتن بالاترین میزان شیب ، ارتفاع ، زبری و درجه انحنا و همچنین وجود اقلیمی مرطوب در بخش های جنوبی آن سبب توسعه اشکال متنوع در منطقه شده است.
    کلیدواژگان: شاخص ژئودایورسیتی، ضریب شانون، ضریب سیمسون، تراکم ناهمواری حوضه های شمال غرب استان فارس
  • امیر کرم، علی احمدآبادی، میترا صابری * صفحات 164-180
    ژئومورفولوژی به مطالعه علمی ویژگی های فرم و شکل سطح زمین می پردازد. وجود انواع لندفرم ها و تنوع آنها به طور عمده با تغییر در شکل و موقعیت زمین و توپوگرافی کنترل می شود. هندسه ی فرکتال اشکال متنوع و نامتقارن پدیده های جغرافیایی و ژئومورفیک را با استفاده از داده های توپوگرافیک و خصوصیات فرم، بررسی و تحلیل، طراحی و مدل سازی می کند. در واقع علاقه مندی و کاربرد مسائل فرکتال در ژئومورفولوژی به این خاطر است که بسیاری از لندفرم های ژئومورفیکی حالت فرکتال دارند و شکل گیری و تحول فرکتال ها را می توان با روابط ریاضی تبیین کرد. در این بررسی از داده های رقومی توپوگرافی ایران در یک شبکه مربعی1320×1500 پیکسل استفاده شد. از روش های شمارش خانه برای بعد فرکتال، نمای زبری(تحلیل طیف نمایی) و تحلیل چند فرکتالی (واریانس کل پروفایل ارتفاعی، تابع همبستگی تعمیمی ارتفاع-ارتفاع و انحنای وابسته به مقیاس)برای تحلیل فرکتال توپوگرافی ایران استفاده گردید. با استفاده از روش شمارش خانه، بعد فرکتالی چشم انداز توپوگرافی به مقدار=2/20 بدست آمده است. همچنین با استفاده از تحلیل طیف توانی در فضای فوریه پروفایل ارتفاع نمای زبری تخمین زده شده است که نمای زبری بدست آمده به مقدار0/48= در رابطه ی = که برای سطوح رندم خودمتشابه و مونو فرکتال صادق است را قانع نمی کند. جهت بررسی و اثبات خاصیت چند فرکتالی پروفایل ارتفاعی، روش های مختلفی به کار گرفته شده تا نمای چند فرکتالی محاسبه گردد. در این نتیجه نشان داده شد که این نماها در رابطه ی ساده ی مربوط به مونو فرکتال ها، بصورت α(n) nα صدق نمی کند. که اثبات کننده ی خواص چند مقیاسی در توپوگرافی ایران است. این پژوهش می تواند زمینه را برای تحقیقات بعدی هندسه فرکتالی در عرصه های جغرافیا، ژئومورفولوژی، زمین شناسی، محیط زیست و سایر علوم زمین مهیا و هموارتر سازد.
    کلیدواژگان: ژئومورفولوژی، توپوگرافی، هندسه فرکتال، ایران
  • ابراهیم غلامی، سید مرتضی موسوی، مریم عزتی * صفحات 181-195
    ویژگی های ژئومورفیکی ساختارهایی که در نتیجه ی بالاآمدگی تکتونیکی ایجاد می شوند اطلاعات باارزشی در رابطه با نیروهای تکتونیکی به وجود آورنده ی آن ها را فراهم می کنند. منطقه ی مورد مطالعه یکی از سرشاخه های انتهایی گسل نهبندان می باشد که درشرق ایران و شمال بیرجند قرار دارد. هدف از این پژوهش تفکیک مناطق با بالاآمدگی متفاوت در طول کوه های شکراب می باشد، برای رسیدن به هدف پژوهش از داده های صحرایی، داده های توپوگرافی و شاخص های ژئومورفیک استفاده گردید. با استفاده از عملیات صحرایی گسل ها که یکی از مهم ترین ساختارها در منطقه ی مورد مطالعه هستند شناسایی گردید. شاخص های ژئومورفیک که در این پژوهش استفاده گردید شامل: نسبت عرض کف دره به ارتفاع دره (Vf)، انتگرال هیپسومتریک (Hi)، منحنی هیپسومتریک (Hc)، شکل حوضه(Bs) و زمین ساخت فعال نسبی (Iat)می باشد. محاسبه ی شاخص Vf در کوه های شکراب نشان می دهد کمترین مقدار شاخص Vf و بیشترین مقدار نرخ بالاآمدگی تکتونیکی مربوط به قسمت غربی و شمال شرقی کوه های شکراب می باشد. بیشترین مقدار شاخص های Hi و Hc مربوط بخش های غربی و شمال شرقی منطقه ی مورد مطالعه می باشد. محاسبه ی شاخص Bsنشان می دهد بیشترین مقدار شاخص Bs مربوط به بخش غربی کوه های شکراب است، افزایش شاخص Bs و وجود حوضه های کشیده در قسمت های غربی و شمال شرقی کوه های شکراب نشان می دهد که بیشترین بالاآمدگی مربوط به قسمت غربی منطقه ی مورد مطالعه است. نتایج این پژوهش نشان می دهد در مناطقی از کوه های شکراب که شاهد بیشترین تراکم گسل های تراستی هستیم، تحت تاثیر عملکرد مولفه ی فشارشی گسل های تراستی بالاآمدگی تکتونیکی نیز افزایش یافته است. وجود گسل های تراستی در قسمت های غربی و شمال شرقی منطقه ی مورد مطالعه باعث فشارش، بالاآمدگی تکتونیکی و ایجاد دره های V شکل گردیده است.
    کلیدواژگان: بالاآمدگی تکتونیکی، تجزیه و تحلیل ریخت زمین ساختی، شاخص های ژئومورفیک، کوه های شکراب، شرق ایران
  • مجتبی یمانی، ابراهیم مقیمی، ابوالقاسم گورابی، سید محمد زمان زاده، ابوطالب محمدی * صفحات 196-215
    یکی از عوامل زمین ساختی که نقش قابل توجهی در شکل زایی دارد آتشفشانها و مواد مذاب ناشی از آن ها است. فوران های آتشفشانی باعث دگرشکلی مورفولوژی و ایجاد ساختمان لندفرمی جدید می شود. آتشفشان دماوند به عنوان یک عارضه ساختمانی با فوران های متوالی خود طی کواترنری تغییرات قابل توجهی را در پیرامون خود ایجاد نموده است. در این پژوهش، نقش آخرین گدازه های دماوند در ایجاد دریاچه های سدی مورد بررسی قرار گرفته است. برای دستیابی به این هدف روش تحلیلی و بازسازی زمانی تغییرات به کار گرفته شده اند. تکنیک کار مقایسه مورفومتری پادگانه های دریاچه ای و سدهای گدازه ای به سه روش مقایسه ارتفاع و ضخامت رسوبات آبرفتی، تعیین حدود گسترش رسوبات دریاچه ایی و باز یابی آخرین حد ارتفاعی گدازه های مشرف به دره ها استوار است. دریاچه هراز در ارتفاع 2550متری و با مساحت 04/52 کیلومتر مربع، دریاچه لار در ارتفاع 2580متری با مساحت79/68 و دریاچه دلیچای در ارتفاع 3780 متری از سطح دریا و با مساحت 25 کیلومتر مربع قرار گرفته اند. این سه دریاچه به صورت تقریبا همزمان شکل گرفته اند. جریان های گدازه ای این سه دریاچه را از هم جدا و به صورت متوالی کنار هم قرار داده اند. دریاچه ها از طریق تندآب ها با هم مرتبط بوده که منجر به تشکیل مجرای فعلی شده است.
    کلیدواژگان: دماوند، دریاچه سدی، پادگانه دریاچه ای، دیرینه ژئومورفولوژی
  • لیلا امینی، عطاءاله عبداللهی کاکرودی * صفحات 216-230
    تصاویر سنجش از دور ابزاری مناسب جهت برآورد عمق در مناطق ساحلی است. در این پژوهش، به منظور مطالعه مناطق کم عمق ساحلی، از تصاویر لندست-8 و داده های هیدروگرافی که با روش اکوساندر جمع آوری شده استفاده شده است. هدف از این پژوهش، عمق سنجی از نواحی جنوب شرقی ساحل دریای خزر از طریق آموزش شبکه عصبی است. تصحیح اتمسفری Dark Object Subtract (DOS)، تصحیح رادیومتریکی (تبدیل درجات روشنایی به بازتاب)، تصحیح درخشندگی خورشید و در نهایت ماسک کردن مناطق آبی از مناطق خشکی، از جمله پیش پردازش های لازم است که بر روی باندهای آبی ساحلی، آبی، سبز و قرمز تصویر لندست-8 اعمال شده است. در این پژوهش برآورد عمق از طریق شبکه عصبی در دو حالت بررسی گردد. در حالت اول، هر یک از چهار باند به عنوان داده های ورودی و داده های عمق متناظر با هر یک از این پیکسل ها به عنوان هدف به شبکه عصبی معرفی گردید. و در حالت دوم، داده های عمق به روش میانگین فازی، به شش کلاس تقسیم بندی شدند و اطلاعات هر کلاس بصورت جداگانه به شبکه ارائه شد. در هر دو حالت مورد بررسی، سهم داده های آموزشی، داده های اعتبارسنجی و داده های آزمون از داده های ورودی به ترتیب 60 درصد، 10 درصد و 30 درصد می باشد. نتایج حاصل از شبکه عصبی نشان می دهد که دقت عمق برآورد شده در کلاسه های مختلف، متفاوت است و بیشترین دقت ( RMSE =0.11و0.90 R2 =) و کمترین دقت ( RMSE =0.11و0.67 R2 =) به ترتیب به محدوده عمق های 97/3- تا 1/3- و 48/4- تا 4- اختصاص دارد. در حالیکه عمق برآورد شده از داده های کل (کلاسه بندی نشده) معادل R2 = 0.94و RMSE =0.16متر بدست آمد. از این رو، با آموزش شبکه عصبی می توان به برآورد عمق از نواحی کم عمق ساحلی با دقت بالا پرداخت.
    کلیدواژگان: عمق سنجی، لندست- 8، کلاسه بندی فازی، شبکه عصبی، جنوب شرقی دریای خزر
  • منصور پروین * صفحات 231-244
    شهر کرمانشاه در طی چهل سال گذشته دارای روند توسعه فیزیکی سریعی در جهات شمالی و غربی بوده است. این امر متاثر از شرایط شرایط ژئومورفولوژیکی دشت کرمانشاه بوده، زیرا پارامترهای ژئومورفولوژیکی در این نواحی دارای شرایط مساعدی برای توسعه ی شهری بوده اند. گسترش شهر در این نواحی نیز تاثیرات مهمی بر لندفرم ها و چشم انداز های ژئومورفولوژیکی منطقه به جا گذاشته است. هدف این پژوهش، شناخت تاثیرات متقابل ژئومورفولوژی و توسعه ی شهری در شهر کرمانشاه در چهار دهه ی گذشته می باشد. بنابراین در ابتدا نقشه ی عوارض ژئومورفولوژی محدوده ی شهر کرمانشاه ترسیم گردید. سپس روند توسعه ی شهر در سال های مختلف بر اساس تصاویر ماهواره یی در ارتباط با نقشه ژئومورفولوژی مورد ارزیابی قرار گرفت. نتایج نشان داد، لندفرم های ژئومورفولوژی جهت توسعه ی شهری را تعیین نموده و توسعه ی شهر کرمانشاه بیشتر در جهات شمالی، غربی و شرقی بر روی لندفرم هموار دشت آبرفتی بوده است. سه لندفرم هموار و مناسب دشت آبرفتی، مخروط افکنه و دشت پایکوهی در مجموع 72% مساحت شهر کرمانشاه را در برگرفته اند. توسعه ی شهری در قلمرو لندفرم های مخاطره زا به علت وجود محدودیت های ژئومورفولوژیکی در نیمه ی جنوبی شهر کرمانشاه می باشد. توسعه ی شهری باعث نابودی بستر رودخانه های چم بشیر و آبشوران شده و لندفرم های دیگر همچون دشت آبرفتی، مخروط افکنه و... به چشم انداز شهری تبدیل شده و روند تکاملی آنها متوقف شده است. این تغییرات در لندفرم های ژئومورفیک می تواند در آینده منجر به ایجاد مخاطره در مناطق شهری گردد.
    کلیدواژگان: ژئومورفولوژی، توسعه ای شهری، لندفرم، سنجش از دور، شهر کرمانشاه
  • امید رحیمی، فریبا اسفندیاری درآباد *، مهران مقصودی صفحات 245-260
    ارتفاعات چهل چشمه (چل چه مه) در دیواندره استان کردستان تعداد زیادی از شواهد یخچالی شامل سیرک های یخچالی و یخرفت های دوره ی پلیئستوسن را در خود جای داده است. میزان ارتفاع خط تعادل در ارتفاعات چهل چشمه به منظور بازسازی محیط و آب و هوای دیرینه در طول آخرین دوره ی حداکثر گسترش یخچالی با استفاده از بررسی های میدانی ، تهیه ی نقشه های ژئومورفولوژی بر مبنای نقشه ی توپوگرافی 1:50000، استفاده از مدل رقومی ارتفاعی 5/12 متری و به کارگیری روش های نسبت مساحت انباشتگی به مساحت کل، متوسط ارتفاع یخچال ها (کروسکی) و روش نسبت تعادل مساحت – ارتفاع محاسبه گردید. میزان ارتفاع خط تعادل در طول آخرین دوره حداکثر گسترش یخچالی در ارتفاعات چهل چشمه حدود 2905 متر از سطح دریا برآورده شد. میزان ارتفاع خط تعادل کنونی با استفاده از روش لای و همکاران و استفاده از داده های هواشناسی 4683 متر از سطح دریا برآورد گردید. با در نظر گرفتن میزان پایین آمدگی ارتفاع خط تعادل به میزان 1778 متر میزان متوسط کاهش دمای سالیانه در طول دوره ی حداکثر گسترش یخچالی °5/11 بوده است. با مقایسه ی میزان پایین آمدگی ارتفاع خط تعادل و میزان کاهش دمای محاسبه شده با دیگر مطالعات انجام شده در ایران و جهان حداکثر گسترش یخچال ها در ارتفاعات چهل چشمه منطبق با آخرین دوره ی حداکثر گسترش یخچالی در حدود 5/26 الی 19 هزار سال قبل و تحت تاثیر شرایط آب و هوای سرد و خشک بوده است، همچنین در مقایسه با مطالعات رایت و همکاران در یخچال های ارتفاعات کردستان میزان کاهش دما حدود 12 درجه سانتی گراد و میزان پایین آمدگی ارتفاع خط بین 1200 - 1800 متر بوده است.
    کلیدواژگان: آخرین دوره حداکثر گسترش یخچال، ارتفاع خط تعادل، نسبت تعادل مساحت-ارتفاع، چهل چشمه
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  • Hasan saddough, Mohammad mahdi hoseinzadeh*, Khalil rezaee, Iraj rahmani, Samira chezgheh Pages 1-17
     
    Introduction
    One of the subjects about alluvial fans is their sedimentary characteristics. The purpose of this study is to analyze and compare the Chitgar and Kan alluvial fans located in the southern slopes of central Alborz in Tehran province and the correlation between the sediment factors affecting soil resistance and determine the most important factor in soil resistance. The study area in this research is Kan and Chitger alluvial fans, located in the northwestern part of Tehran and in the basin of Kan and Chitgar rivers.
    Methodology
    At First, For better study and comparison of the parts, the Alluvial Fan were divided into three upper, middle and distal.Then the physiographic characteristics of each section were calculated. In the field operations, 24 trenches in the study area were excavated and all the layers were sampled and their position was recorded with GPS. After collecting samples, sedimentology studies, including classification and determination of particle size, determination of particle size parameters and clay measurements by pipet method were used. Finally, by using Excel and Gradistate soft wares, all statistical parameters and different charts for particle size by Folk method and morphometric analysis and particle size by pipet method were prepared and these two alluvial fans were compared in terms of sedimentary texture according to their basin. Finaly To compare geotechnical properties of sediments in two Fans, soil resistance factor was used.
    Results and discussion
    After examination of the sediment, two Alluvial Fans aggregates were observed in which both conifers follow from the exponential pattern of particle size reduction from top to bottom. So that in the upper parts the greatest concentration is observed in the coarse particles and fine particles are in abundance. Of course, in some trenches there are also thick and massive deposits of clay lenses with low thickness, which are due to sudden increase or decrease of energy in this part. There are no coarse particles in the bottom part, but fine particles become noticeable. Although this rule does not apply to the end of the cone, because there are even more than 2000 microns of coarse-grained sediments due to the interference of the Alluvial Fan sediments of Karaj. In both Alluvial Fan, the sedimentation in the flood plain is more mass and the diameter of the sediments is reduced from the vertex to the end of the Alluvial Fans. The relatively good sort, especially in the upper parts and the small amount of clay, represents the sediment deposited by water in the flood plain.
    The results of sediment compaction in two conifers from top to bottom resulted in the following
    results
    - The range of upward/downward ratio changes in both fans shows a downward trend.
    - The range of sphincter changes in both Alluvial Fan from top to bottom of the Alluvial Fans shows an incremental trend.
    - The magnitude of the factor shape, from the top down to both cones, shows an incremental trend.
    - The range of rounding changes in both cones from top to bottom shows an incremental trend.
    - The range of three-axis size variations in both cones shows a decreasing trend from top to bottom.
    - Investigating the correlation between particle size and Particle form to soil resistance indicates that the average factor of particle diameter and rounding dimension shows the highest correlation with soil resistance, which is the first positive and the latter negative
    Conclusion
    Based on the results of the laboratory tests and the analysis of the above data, general results of the research are as follows. The Chitgar Alluvial Fan in the middle diameter of the particles from the upper to lower parts shows a gradual decrease, although the cone-shaping from the upper to mid-point shows a decreasing trend, but in the end part due to interference with the intermediate sediments of the cone This is the order of Karaj. The variation of the three dimensions in both cones is normal and with increasing distance from the river's origin, the trend is decreasing. Also, in both fans, the form of sediment changes from top to bottom from the plate and the bar to the sphere and cubic. In general, it can be said that the sediment deposited in both conifers is due to coarse-graining, mass sedimentation (which indicates a sudden decrease in the energy of water), and the insignificant amount of clay from flood-river type. . The results of correlation showed that: sediments with coarse-grained and angular particles are more resistant to soil resistance in terms of construction
    Keywords: Kan, Chitgar, Alluvial Fan, SPT
  • shahram roostaei*, Davod Mokhtari, zahra Ashrafi fini Pages 18-30

    Nowadays, differential interferometric synthetic aperture radar (DInSAR) is one the most practical techniques measuring earth surface movement. Using this technology makes continuously monitoring of small earth surface movements with high precision and in a wide range Possible. By studying the ground surface displacement, we can find effective parameters influencing the Earth's displacement process, which will be effective in geophysical modeling and determination of the necessary strategies to deal with this type of phenomenon. Landslide is considered as one of the geophysical phenomenal of sloping instabilities that causes displacement of landslide along the tilt direction. These displacements cause dramatic financial losses and heavy casualties.
    Materials and Methods
    In this study, the detection of active landslides and their displacement in the Taleghan watershed have been resolved by differential interferometry processing using satellite radar images of Envisat- ASAR satellite in high-pass mode. The required radar images were provided by submitting a research proposal on the University of Delft website while having their consent. Analysis of Taleghan watershed basin radar images for its specifications was done using the EOLI-SA software. 29 images of SAR sensor from Envisat- ASAR satellite were used at present study. Images used are obtained by descending imaging geometry technique (located on the North-South circle of latitude), which are produced by the C band wavelength from the microwave spectrum of electromagnetic waves (λ = 5.6 cm). These images are corrected by Scan Line corrector (SLC) and were collected since 2003 till 2009. Differential interferometry processes were performed to detect landslides locations and calculate their displacements by ENVI 4.2 software. The entire process was carried out through field surveys and a digital elevation model. The final stage of differential interferometry process is transformation of absolute phase to the displacement map and geocoding which is based on the elliptical surface of the WGS84 metric image system.Since there was no direct measurement of dissociated surfaces dislocation in the studied area, the aim of this study was accuracy assessment of archived results by field surveys and overlapping them with the Google Earth software.

    Resutls anddiscussion
    Results of processing differential radar interferometry of pair images were collected since July 18, 2003 till March 31, 2009. In this study, a total number of 17 slide bulks were selected in the Taleghan watershed based on field observations. Then, the level of instability of these bulks was analyzed using SAR sensor images for the mentioned period.
    Most identified landslides were in the vicinity of residential villages and riverside networks, and their spatial distribution shows that most of the identified areas are matched with previous landslides.In other words, some of the old landslides in the region are still active. Among these slide bulks, Zidasht sliding zone with 7.2 km length is the smallest one on the eastern slope of the basin and the Minavand slippery zone with 4206 km length is located on the western slope of the basin.One of the important points of the chosen sliding bulks is their proximity to residential areas located in the basin. The largest displacement occurred at the surface of Composite slide bulks, as per maximum amount of depression happened in Minavand slide bulk and was 2.5 cm.The spatial distribution of the identified landslides resulted from the processing of coupled radar images and their examination indicates that the largest displacement has happened since 2004 till 2008.Comparison of radar images shows that although these slide bulks were in the northeastern and upstream of hillsides and rivers in the past, they are now located in the western direction, and some landslides which were active in previous periods, haven’t shown any change in their surface during this period and the amount of displacement observed was lower than before.
    Conclusions
    The results showed that some of the slopes of the Taleghan watershed are still unstable and the compatibleness of landslide site location with some old landslide implies the activeness of old landslides of the region.The findings of this research have been evaluated through field observations and determination of the slide bulks by evaluating radar images. Also results indicated that all sliding surfaces were detected with high precision. Therefore, it can be declared that the differential interferometric synthetic aperture radar method (DInSAR) is an efficient technique for identifying the landslides.Field observations showed that most of identified landslides conform to the old ones. Also displacements at the surface of these landslides determined to be still active. At present, the slide bulks of Minavand and Mehran are considered as the most active and dangerous slide bulks of all kind.
    Keywords: slope instability, Differential interferometry, radar images, taleghan watershed
  • Reza Alipoor*, Amir Hossein Sadr, Hossein Nazari Dabir, Sahar Ghamarian Pages 31-56
     
    Introduction
    The recent studies about the geomorphology is more based on the systematic comparison of the features and deposits. It also focus on determination of the primary forms of features and identification of processes. Qualitative measurement includes examining the shape of the earth's surface. Quantitative measurements allow the comparison of different landforms and calculation of less-understood parameters and allow identification of specific features including the level of tectonic activity. Geomorphic evidence can be evaluated using quantitative and qualitative methods, which is the quantitatively assessment is known as morphometric method. The use of geomorphic indices is a common method for classification of the tectonic activity. In this research, assessment of the active tectonic structures on recent geomorphology of the Green Mountains have been studied using morphometric indices and also effects of the Nahavand fault zone on the drainage network of the Grin Mountain (south west of Nahavand) has been investigated.
    Methodology
    In this research, structural maps, drainage network map and digital elevation model (DEM) of the study area were prepared using topographic map of the Hamadan, geological maps of the Nahavand and Malayer and Landsat 7 satellite images. Then, the stream length-gradient index (SL), asymmetry factor index (Af), transverse topographic symmetry index (T) and mountain front sinuosity index (Smf) were calculated for 47 basin in the study area. Finally, the results of these indices were compared by analyzing of the fractal dimension of the study area.
    Results and discussion
    The drainage pattern of the study area have two main NW-SE and NE-SW trends. The value of the SL index varies from 962 to 50 in the region with high and low tectonic activity, respectively. The value of this index is increased along the faults trend of the region and intersection of the drainages with active structures. It can be proposed that the tectonic movements, especially uplift, have increased the gradient of the drainages. According to the results of the Af index, 17 basins is classified in class 1 (high activity), 16 basins in class 2 (moderate activity) and 14 basins in class 3 (low activity). The existence of active fault system in these regions can be attributed to this asymmetry and tilting. The values calculated from the T index are classified in the classes 1 and 2, which indicate the asymmetry of basins, especially in the central part and perpendicular to the Green Mountains. In 19 basins, the values of this index are classified in class 1, in 24 basins in class 2 and just in 2 basins in class 3. The mountain front of the study area were divided into 10 sections along the Garin Mountain, in order to assessment of the Smf index. Then, from the north to south, this index was calculated for different sections. Measured values of the Smf index for most part of the study area show values close to 1, indicating that the northern part of the Green Mountains have a higher relative activity. In this study, all indices were combined, in order to classification of the study area based on Iat index. For each basin, the mean values of the geomorphic indices (S/n) were calculated and classified into four classes of index of relative tectonic activity (Iat). Considering the final zoning map of the relative tectonic activity in the study area, it can be proposed that the basins of the central and southern part of the region have more relative tectonic activity. Also, fault and drainage network layers were mapped in the Arc GIS software and the fractal dimension was calculated for the study area by using the Box Counting method (the most common method for fractal analysis). Regarding the surface geomorphology, the study area was divided into 6 squares with dimensions of 16 km, in order to applying the Box Counting method. In the fractal study, the fault system of each square was evaluated separately and the fractal dimension was calculated for each square. Fractal dimensions of the drainage networks were calculated using aerial photos and satellite images similar to the faults map. The maximum and minimum fractal values of faults are 1.87 and 1.41, respectively. Also, the maximum and minimum fractal values of drainages are 1.66 and 1.27, respectively.
    Conclusion
    According to the final zoning map of the relative tectonic activity in the study area, it can be proposed that the central and southern basins of the study area have more relative tectonic activity, where the faults also have a high density in these basins. The activity of fault systems in these basins have played an important role in high rates of relative tectonic activity. Increasing the fractal dimension of the faults indicates less maturation and the activity of the study area. The major and active structures in the Nahavand fault zone in the southern part and along the Garin Mountains caused the uplift and tectonic activity in this part of the study area
    Keywords: Tectonic, Morphometric indices, Fractal, Nahavand fault, Garin Mountain
  • Reza Esmaili*, Razieh Yarmohammadian, Ghasem Lorestani Pages 57-70

    Introduction
    Stream bank erosion can have many geomorphic effects in the river. The erosion of stream bank causes destruction of the river banks, increase the sediment load, river pattern changes, deposition in channel, reduce water quality and decrease of river habitants. In fluvial geomorphology, a set of objective indicators are used for the rapid measurement of river geomorphological characteristics which are known rapid ggeomorphic assessment (RGA). Using these techniques, Effective factors in the occurrence of geomorphic forms on the ground are scored And the sum of the points of all factors describes the conditions. In this research, the stability and instability of the stream bank using RGA methods in the Seymare River have been studied. The study area is part of the Seymareh River with a length of 18 km that located downstream of the Seymare Dam (Dare Shahr county in Ilam province).
    Material and Method
    One of the most commonly used RGA techniques is the channel stability index (CSI). The CSI was proposed by Simon and Klimetz (2008) and requires measuring the bank height, bank face length, average diameter of streambed sediment, bed and bank protection, degree of constriction, streamnank erosion, evidence of mass movement, riparian vegetation, deposition in near bank and stage of channel evolution model. Each index is scored and sum of score is used to categorize each stability category of stream reach include: 20 is considered highly unstable.
    The Oklahoma Ozark streambank erosion potential index (OSEPI) was developed by Heeren et al (2012). In this method, eight factors, including the bank height, bank angle, Percentage of Bank Height with a Bank Angle Greater than 80o, evidence of mass movement, bank Unconsolidated Material, streambank protection, riparian woody-vegetation and Stream Curvature are scored. According to OSEPI, the sum scores of 0-25 are highly stable, 35-26 moderately stability, 45-36 stable, 55-46 unstable, 65-56 Moderately Unstable and 85-66 highly unstable. In the study area, 14 reaches were investigated and indicators of both methods were measured.
    Results Substrate sediments at all reaches were in gravel size and the bed and bank had no artificial protection. The height of the critical banks has varied from 6 to 34 meters due to its proximity to the to the alluvial terraces. It is observed evidence of mass movement landslide in most reaches. Riparian vegetation (tree and shrub)was found in 25 to 75 percent of the river corridor. Bank attach sedimentary forms have been found in 10 to 75 percent of the length of the reaches. in terms of the channel evolutionary model, the most of reaches are in stage 5.
    In the CSI method, the total score of the river reaches varies from 14 to 18.5 and all reaches are falled in the moderately instability group. The total score of indicators in the OSEPI method varied from 47 to 60, Which 86% of the reaches are being in unstable group and 14% fall in Moderately Unstable class. In order to investigate the factors affecting the instability of river bank, the scores of each index were calculated in relative score in both methods. Based on the average relative scores of each index in the CSI method, the most influential factors on the bank instability are the bed incision, evidence of mass movements, bank erosion and channel evolution model index with scores of 0.82, 0.77, 0.75 And 0.75 respectively ranked first to fourth. In the OSEPI method, bank heights, bank Unconsolidated sediments, evidence of mass movements and riparian vegetation with scores 1, 0.64, 0.6 and 0.56 were the most effective indexes. Relationships were calculated between CSI and OSEPI based on all 13 reaches with an R2 (determination coefficient) of 0.71.
    Conclusion
    The results of the scoring of the indexes and relative scores of factors in the streambank instability show that the OSEPI method provides more suitable indicators and its descriptive division is better than the CSI method.
    These methods show the current conditions of the reaches in terms of stability and instability and they aand they can not predict instability in the future. The instability of river bank is different in regions depending on the geological, climatic and hydrological conditions. Therefore, they can be used to modify some of the indicators.
    Keywords: streambank erosion, Rapid Geomorphic Assessment (RGA), Saymareh, Ilam
  • Aghil madadi*, Hassan Mozaffari Pages 71-90
    Understanding geomorphologic landforms and studying its developments and changes in all regions, especially mountainous areas, in order to manage the environment in different fields is the important and essential needs of geomorphology. The internal and external dynamics of the Earth constantly cause changes in geomorphologic landforms. Therefore, recognizing these changes and developments for better management in various natural and human contexts is an essential issue. Mountainous areas due to their difficulty in traffic challenge field studies. Geomorphology also uses the latest technologies of the world, such as remote sensing, to accelerate the advancement of goals and needs, in line with other sciences. Landsat TM and OLI satellite imagery were used to identify the surface landforms of Sojasrood basin and to investigate the trend of changes during the years 1986 to 2018. To identify the landforms, field surveys were performed using Google Earth images and topographic maps.Then, by maximum Likeihood Supervised Classification Methods Neural network and Support vector machine have been extracted from the original and main landforms. The results of classification accuracy assessment showed that the maximum Likeihood method with total accuracy of 97.70 Kappa coefficients 96 Percent in 1986 and 2018 has a better performance in geomorphologic mapping and change process than the other two methods. In order to investigate landform variations and detect changes over a period of 32 years, the maximum Likelihood category and MNF algorithm were used in the ENVI software environment. The final results showed that the Vegetation zones and alluvial plain had 159/479 and 26/572% increase in area, respectively. Mountains and hills, alluvial terraces, alluvial cone and new alluvial were reduced by area. Also, the results of MNF algorithm show that the maximum intensity and speed of changes are related to alluvial plains, mountains and hills, and the least speed of changes related to the alluvial cone.
    Keywords: Landform variations, supervised classification algorithms, MNF algorithm, Sojasrood Basin
  • hamid Babolimoakher*, Kourosh Shirani, Alireza Taghian Pages 91-116

    Landslide is a natural disaster resulted from geomorphologic, hydrologic, and geologic conditions along with human factors. As of present, many pieces of research have been performed to achieve such a purpose based on various models. However, many of such works have failed to provide satisfactory results due to failure to consider surface landform, so that limitations have been encountered when it came to the application of their findings. This highlights the necessity of using novel methods based on quantitative criteria of landform to identify the zones susceptible to landslide, so as to conduct proper planning for such zones. In this respect, morphometric parameters can represent landform characteristics of the hillsides susceptible to landslide. Moreover, in tectonically active areas, instability of the hillsides can be observed in the form of various types of landslide. This shows that, when it comes to the assessment of landslides, one should further consider neotectonic activities by means of geomorphologic indices.
    In the present research, a total of 20 effective factors were used to assess accuracy of a landslide susceptibility zoning map; the factors include 14 conventional factors along with 6 geomorphometric factors. For this purpose, firstly, independence of the factors affecting the landslide was analyzed by performing Multicollinearity reach tests. To this end, two important indices, namely tolerance (TOL) and variance inflation factor (VIF), were used to undertake multi-directional reach test. These two indices are commonly used when running generalized linear models for analyzing the relationship between independent variables or conducting multi-directional reach test. Even though no consistent principle is presented for determining thresholds of these two indices (VIF and TOL) in multi-directional analysis and estimation of the factors affecting landslide, but records of the research works performed on this topic show that, multiple-correlation problem will arise (i.e. the data or independent variables are not correlated at all) if the value of VIF is smaller than 5 or 10 and the value of TOL is higher than 0.1 or 0.2. Moreover, in order to assess the correlation between the landslide and the selected factors, the weights obtained from the confidence factor (CF) model were used in the form of bivariate statistical analyses. The weights calculated by this model were further employed to prepare factorial maps and convert them into binary maps (wherein the levels with negative and positive weights were represented by 0 and 1, respectively) to be introduced into the conditional independence test. Continuing with the research, once finished with entering the weights obtained from the CF to the logistic regression model, the model coefficients were extracted. Using the obtained weights, the model was run to prepare a landslide susceptibility zoning map following either of two approaches, i.e. with and without considering geomorphologic indices along with other effective factors. Finally, Receiver Operating Characteristic (ROC) curve was used to validate, assess, and compare the maps obtained via either of the two approaches.
    Based on the results of multiple correlation test, no correlation was obtained between the independent factors with VIF value of at most 3.559 and TOL values of at least 0.253. All of the values of VIF of the independent factors were lower than the critical value (5 or 10), while all of the values of TOL of the independent factors were higher than the calculated value by the critical theory. Maximum and minimum values of VIF were found to be 3.559 and 1.101, respectively, and the corresponding values to TOL were 0.253 and 0.895, respectively, which referred to the land roughness and slope direction, respectively.
    The results obtained from the CF model showed that, the land roughness values exceeding 14 followed by slopes exceeding 40% possess the largest CF weights, among other levels of the considered factors, while waterway densities ranging between 0 and 10 and precipitations lower than 550 mm exhibited the lowest CF weights. According to the results obtained from the logistic regression model, the slope, NDVI, and slope direction exhibited the highest correlation coefficients, making them the best predictors of landslide occurrence in the region. Combing the weighted maps, zoning maps were prepared via the two approaches. Accordingly, 17.06% and 8.27% of the area understudy were identified as very highly susceptible to landslide, for the cases with and without considering the effects of geomorphologic factors, respectively. In addition, based on the results of ROC, the area under the curve was evaluated as 0.88 and 0.82 for the cases with and without considering the effects of geomorphologic factors, respectively. This confirms higher efficiency of the models into which geomorphologic factors are incorporated along with other common parameters considered in landslide susceptibility zoning.
    Keywords: landslide, zoning, geomorphologic, logistic regression, Fahlian river basin
  • Amir safari*, mojtaba yamani, Amir karam, Parivash karami Pages 117-135

    Landslide as a natural hazard has always caused a lot of damage. Identifying the effective factors in the occurrence of this phenomenon and its risk zoning is one of the basic and practical methods for achieving its control strategies. The geomorphic setting of Alborz Mountain is a result of complex interactions involving neo-tectonic movements and processes of erosion and deposition. In this research, the aim of the study is to investigate the relationship between active tectonics and the potential of landslide occurrence in the Jajrood watershed as one of the mountainous regions of the country. The main research tools are Morphotectonic Indicators. Based on 10m-resolution DEM data, a total of 39 basins were extracted using ArcGIS . The Jajrood basin is up to the Latian dam with a total area of 949 km2, located between the latitudes 51 °,22ˊ),( 51 °, 51ˊ) East and the latitudes( 35 °,45ˊ),( 36 °,50ˊ) Is located . Geological and lithologic features of Jajrood basin and important fault systems such as Mesha-Fashem fault and North Tehran fault in this area, as part of the complex tectonic system of the southern Alborz, have caused the proposed basin to be a suitable place for evaluation of tectonic indices Be active. A total of 28 landslide were visually interpreted from satellite images and published documents. Seven geomorphic indices were calculated for each basin including the relief amplitude,(RA), hypsometric integral,(HI), stream length gradient,(SL), basin shape indices,(BS), fractal dimension, (FD),asymmetry factor,(AF), and ratio of valley floor width to height,(VF). These geomorphic indices were divided into five classes and the ratio of the number of the landslide to the number of the basins for each geomorphic index was computed and analyzed for every class. Average class values of the seven indices were used to derive an index of relative active tectonics (IAT). IAT values range from 0/64 to 5/79 with an average of 63/2 and a standard deviation of 1/07 is relatively active tectonic indication. Deviation from the relatively low benchmark shows that the tectonic activity in the study area is less affected. The ratio of the number of the landslide to the number of the basins was computed for every class of IAT. The landslide ratio to drainage basins for classes 4 and 5 is clearly has a relatively high frequency. The degree of probable risk level was then defined from the IAT classes. The degree of likelihood of a landslide hazard is generally high across sub-basins. Areas with a much higher probability degree are primarily distributed in the north and in the central region.Finally, the landslide hazard was evaluated for each drainage basin based on the combined effect of probable risk level and occurrence frequency of the landslides. The results show that there is a good agreement between the IAT class and the number of landslides to the number of sub-basins. About 85% of the sub-basins where landslides are occurring at high and very high levels, while Of the 27 sub-basins without landslides, about 33% are at high and very high levels. In order to validate and evaluate the accuracy of the model, two factors were used: total quality (QS) and accuracy (P). The total quality (QS) value was 0.97 and the accuracy of the method (P) for high risk and very high risk classes was 0.79. The sum of the quality and accuracy of the method indicates the correctness or usefulness of the method for predicting landslide hazard. The findings showed that the Jajrood basin was very active from tectonic viewpoint and this has increased the talent of landslide. These results indicate that the geomorphology conditions by active tectonics provide an important basis for studying the landslide hazard, although other factors also affect the occurrence of landslide
    Keywords: Jajrood basin, landslide, Morphogenetics, Active tectonic
  • asadullah hejazi*, shahram roostaei, maryam ranjbarianshadbad Pages 136-150
    Investigating the factors affecting landslide occurrence, providing vulnerability maps and avoiding areas susceptible to landslide can help to reduce the potential damage and risk management of this phenomenon. Therefore, the purpose of this study is to evaluate and constrain Hajilerchay basin in terms of landslide hazard. In order to investigate and zoning the risk of landslide in this basin, the maps and layers of information are the main factors affecting this phenomenon such as slope, gradient direction, precipitation, lithology, land use, distance from fault, distance from the waterway and altitudes. Geographic Information System (GIS) was developed and then, using satellite images and field operations, landslides were identified in the area. The weight of each factor was calculated using the Dempster-Shepherd theory. Weights are included in the operating maps and for each factor we obtain a weighted map. In the next step, weighted maps combined and finally a landslide hazard zonation map was prepared in five categories with very little or very high risk. The results of this study indicate that about 9.43% of the area of the Hajilerchai basin is very likely to occur, as well as 22.42% of the probability of occurrence, 28.09% of the probability of occurrence, 25.33% of the probability of occurrence, and The probability of occurrence is very low in 14/69%.
    Keywords: Landslidezonation, Dempesters-sheffer probabilistic theory, Geographic information system, Hajilar Chay basin
  • leila Golimokhtari*, Saeed neghaban, najmeh shafiei Pages 151-163

    The term geodesy is equivalent to morphological diversity. When it comes to geological diversity, it refers to global concepts of geological diversity and geomorphologic diversity, and we briefly call it geological diversity, and includes a variety of geological diversity, Mineralogy, Stratigraphy, Lithology, Sedimentology ... And with the new Global Approach to Geodesy, the protection of geodesy in the form of the preservation of inanimate nature with the advent of the geoscience world in the world (2008) has been raised, without the existence Geological diversity will be meaningless to protect Geocaching. Natural resources, such as building stones, grains of grains, minerals, natural gas, oil and underground water, are the basis for human beings; it forms the basis of agricultural land and fertile soils; affects our place of life. Enhances our valuable and special environments; an unprecedented archive of climate and past environmental conditions; there is also no rich cultural heritage and history of geodatourism without biodegradation;
    In the meantime, the necessity of attracting tourism to Iran with this regional scope and the many potential that exists to create income and employment and sustainable development is felt on the other hand, Iran, in terms of unique geological and geomorphologic phenomena among the richest The countries of the world and has a great potential for achieving sustainable development in this way. According to forecasts, there are 50 potential areas for identification, establishment, exploitation of tourism, educational and sustainable in Iran for global geopark registration.

    In this study, in order to study the geodesy of the three Fahliyan basin, Nurabad and Rostam basins which are located in the south of Iran in the northwest of Fars province and the central and eastern parts of the city of Noorabad Mamsani and Rustam, these basins total area of ​​ 2005 sq. And geologically, these basins are considered to be corrosive Zagros. Located 935 meters above sea level and 150 kilometers northwest of Shiraz, is located in the center of Fars province. The studied area is located in the Zagros zone in terms of the geological units of Iran.

    In this research, a descriptive and analytical research is descriptive. First, morphometric, morphological, and geological classification layers were prepared. Geological layer of 1.100000 geological maps, morphoclimatic layer of Iranian climatic layer and morphometric layer using altitude layer using TPI index, which is described below. At the end of the layer, the final composition of the three-layer combination The original was created. After this stage, using FRAGTATSE software, five geodecimal indicators including PRD, Simpson roughness coefficient (SIEI), Shannon roughness coefficient (SHEI), Shannon coefficient of Shannon (SHDI), Simpson Diorsity coefficient (SIDI) Calculated. The FRAGTATSE software was used by McGarig in 2002 to calculate geodeiversity.
    Table 4 shows that at the end of the stage and the combination of three morphometric and morphological characteristics of the morphological and morphological characteristics of Simpson and Shannon in Nurabad basin has the highest rate and the same indices in Fahlian and Rostam basins are relatively less. On the other hand, due to the fact that the northern watershed has a wet climate and this region has the highest rainfall in terms of rainfall, and its average annual temperatures are much lower than in other regions, which in some way promotes the development and expansion of morphometric diversity And the rippling variation in the basin level. This has led to the formation of very tall walls of numerous waterfalls, valleys and troughs in the southern parts of the country, and also the water resources in these formations are far more expanding and expanding gardens and forests. Wide

    The results of the indicators applied in each of the three basins are shown by examining the geological status and type of formation in the three studied basins, considering that the diversity of the Formation in Fahliyan is 12 types in Nurabad 10 types and in Rostam 9 this is a kind of determination The high point is the index of Shannon and Simson's variability and roughness indexes in Fahlian Basin. Because the Fahlian Basin has more chasmas than other basins in the Earth's Factor (Mesozoic and Cenozoic limestone formations). In morphometric factors and the final layer of geodesy, the highest value is attributed to the noradabad basin due to its high slope, altitude, roughness and degree of curvature, as well as the presence of wet climates in its southern parts, has led to the development of diverse forms in the region. In this basin, the Shannon and Simpson roughness indexes are equal to 0.307, 0.096, 0.097, and 0.777 respectively. Since geologists have sought to know more about land and access to information and to solve their uncertainties over the years, they have been neglected by Georgetowns and have not had much time to explore the diversity of land. However, it can be said that by examining the world of The geological diversity perspective can be better off than the natural resources of the earth. Despite the importance of geological diversity in various dimensions, this phenomenon is threatened by human activities. Therefore, the need to protect geological geogonality is felt and this is important for the development of geotourism. Protective objectives and practices should take into account different elements of geological diversity, and appropriate planning is appropriate for the Zeusite type. Management in geotourism and The related recreational activities as well as geoparks often depend on the type of geological diversity
    Keywords: Geodesy index, Nourabad basin, Fahliyan basin, Rostam basin, GIS, FRAGTATSE
  • Amir Karam, ali ahmad abadi, *Mitra Saberi Pages 164-180
     
    INTRODUCTION
    Geomorphology is de_ned as the science of Earth's diverse physical landforms with an emphasis on their origin and distribution across the landscape as well as the dynamic processes that shape the topographic features . Enhancing the uptake of geomorphic understanding and its underlying processes play a key role in understanding of physical geography, as one of the major research challenges in geography Fractal and multifractal analysis of topography has long been a very useful method to obtain synthetic topography in geology and geography which has led to a variety of di_erent results. The concept of fractals was rst introduced by Mandelbrot [1967] as a measure of the Earth's topography, the length of a rocky coast line [Mandelbrot,1982] The fractal dimension is a measure of global property of the system in question and in many cases is independent of various details and so it is used to classify di_erent systems and models in terms of the value of the fractal dimension besides other statistical measures.
    However, in various studies in the past (see e.g., Lovejoy and Schertzer (1990); Lavallee et _ al. (1993)), it has been noti_ed that in some cases the topography is not far than simple to be explained with a single scaling exponent such as the fractal dimension, it is rather more appropriate to study topography as a scale invariant quantity that generally requires multifractal measures and exponent functions. This gives rise to an in_nity of fractal dimensions for di_erent statistical moments of a variable are needed to completely characterize the scaling properties.
    There exist a few multifractal studies of topography showing the multiscale properties of the height pro_le over various ranges in length scale (see for example Lovejoy and Schertzer (1990); Lavallee et al. _ (1993); Weissel et al. (1994); Lovejoy et al. (1995); Pecknold et al. (1997); Tchiguirinskaia et al. (2000); Gagnon et al. (2003), J.-S. Gagnon et al. (2006). A similar mono vs multifractal study exists for the arti_cial growth surface models (e.g., Morel et al., 2000). The growth models are studied in both context of monofractality and multifractality (Bouchaud et al., 1993; Schmittbuhl et al., 1995).
    In this Section we use the box-counting method to estimate the fractal dimension of the height pro_le in Iran.
    Methodology
    In this method we consider the Iran's topography shown in Fig. 1. We used the Iran's topography grid data with high resolution on a square lattice of size 1500 _ 1320.
    The heights fhi;jg are known at each grid node (i; j) distributed between the minimum height hmin = -4398 m and the maximum height hmax = 5149 m. In the box-counting method, we consider a cube of size 500 1320 9547 which covers all the height topography.
    The mesh sizes are scaled to unity. At each grid point (i; j), we consider a height column of size 1 1 hi;j with hmin _ hi;j _ hmax. We cover the entire cube with boxes of size 1 1 b, for di_erent length scales b, and then count how many boxes of the grid i.e, Nb, are covering part of the height columns. Then we do the same thing by using a _ner grid with smaller boxes (smaller b). By shrinking the size of the grid repeatedly, we end up more accurately capturing the structure of the pattern of the topography.
    If the the topography has a fractal structure, then one would expect the following power-law relation Using the box counting method, the fractal dimension Df of the height pro_le is thus given by the slope of the line when we plot the value of log(Nb) on the y-axis against the value of log(b) on the x-axis i.e., (6)As shown in FIG. 2, we _nd that the fractal dimension of the Iran's topography is Df = 2:20(1).
    Result and discuion:We find that _(2) = 0:99(0) which gives the roughness exponent _ = _(2)=2 = 0:495(5) in accord with our previous estimates obtained from di_erent methods like the power spectrum analysis and two methods mentioned in Subsections IVA and IV B. We also _nd the higher moment exponents _(3) = 1:39(1) and _(4) = 1:53(1). As mentioned above, for self-a_ne surface one should _nd _(q) = q_ or equivalently, _(q)=q = _. If we test this criteria for Iran's topography, we _nd that _(3)=3 = 0:46(1) and _(4)=4 = 0:38(1) which di_er from our estimate for the roughness exponent _ = 0:495(5). This completes our conclusion that the height pro_le of Iran's topography has a multifractal statistics.
    Keywords: Geomorphology, Topography, Fractal geometry, Iran
  • Maryam Ezati*, Ebrahim Gholami, Seyed Morteza Moussav Pages 181-195


    Introduction
    Landscape evolution represents a morphotopographic balance resulting from interactive competition between tectonics and climate. The development of geomorphic features in response to tectonic uplift provides important information regarding nature, spatial and temporal distributions of tectonic forces in contractional and extensional tectonic regimes. The distribution of tectonic activities in regions experiencing tectonic uplift can be mapped through geomorphic proxie. Commonly, geomorphic indices are useful to classify areas as being very active, moderately active, or inactive. Aim of this research is separating of areas with differental tectonic uplift. Study area (Shekarab Mountain) is located in the East of Iran. In this research, for identifying rate of tectonic uplift geomorphic indices such as valley floor width–valley height ratio (Vf), hypsometric curve (Hc) and hypsometric integral (Hi), drainage basin shape (Bs) and Relative tectonic activity (Iat) were calculated.

    Methodology
    For reaching to the aim of this research field work and Geomorphic indices were used. Indices of active tectonics may detect anomalies in the fluvial system or along mountain fronts. These anomalies may be produced by local changes from tectonic activity resulting from uplift or subsidence. The research design is to analyze several different indices in Shekarab Mountain.
    Ratio of Valley Floor Width to Valley Height (Vf):Vf is defined as the ratio of the width of the valley floor to its average height (Bull and McFadden, 1977; Bull, 1978) and is computed by Vf=2Vfw/[(Eld–Esc)]+(Erd–Esc)] (1)  Hypsometric Integral (Hi):The hypsometric integral is an index that describes the distribution of elevation of a given area of a landscape. The index is defined as the area below the hypsometric curve and thus expresses the volume of a basin that has not been eroded. The simple equation that may be used to calculate the index is Hi = (average elevation – min. elevation) / (max. elevation – min. elevation). (2)
    Index of Drainage Basin Shape (Bs):Bs (Ramirez-Herrera, 1998) expressed by the equation Bs=Bl/Bw (3)  Where Bl is the length of the basin measured from the headwaters to the mouth, and Bw is the width of the basin measured at its widest point.
    Relative tectonic activity (Iat):Several index combined to provide information of relative degree of tectonic activity. To provide Iat index is obtained by averaging of different classes of geomorphic indices (S/n) and divided in to four classes. Class 1 is very high tectonic activity with values of S/n between 1 and 1.5; class 2 is high tectonic activity with values of 2>S/n>1.5; class 3 is moderately active tectonics with 2.5>S/n >2; and class 4 is low active tectonics with values of S/n>2.5 (El Hamdouni et al., 2008).

    Result and Discussion
    In this study, we have used 1: 25,000 topographic maps with 50 m contour intervals. This projection was the UTM zone 40 N. Values of Vf vary from a low of 0.3 for the west part of Shekarab Mountain where it is deeply incised into hard bedrock, to a high of 3.4 at east part of Shekarab Mountain. Hi index computed for each subbasin, ranges from 0.8 (Subbasin 1) to 0.3 (Subbasin 51). Computing of hypsometric integral (Hi) shows that actives part of Shekarab Mountain is west and north eastern part of Shekarab Mountain (subbasins 1, 24). Calculating hypsometric integral shows that in west and north eastern side of study area (subbasins 1, 24), rate of uplift are faster than rate of erosion. Bs was calculated for Shekarab Mountain, The highest value of Bs index is related to western basins of Shekarab Mountain. The highest class values for Iat mainly occur in the west and north eastern of Shekarab Mountain, while the rest of study area has classes of Iat suggesting moderate to low tectonic uplift. The distribution of indices defines areas associated with different rates of tectonic activity. Within the study area tow subbasin (subbasin 1 and 24) is about class 1 (very high relative tectonic activity). Result of this research shows that highest amount of tectonic uplift is about the west and north east side of study area, and in the areas of Shekarab Mountain that thrust fault were more concentrated tectonic uplift increased.

    Conclusion
    The values of morphometric indices valley floor width–valley height ratio (Vf), hypsometric curve (Hc), hypsometric integral (Hi), drainage basin shape (Bs) and Relative tectonic activity (Iat) compared with lineament and geological map. Calculating Af and T indices shows that most streams of study area is tilted toward the South. Computing of Hi index show that main basin is in youthful stage. Computing of SL index shows that highest amount of SL index is related to fault 3. Calculating of Vf index indicate that lowest value of Vf index is related to fault 3. Computing of geomorphic indices shows that fault 3 are more tectonically active than other faults of study area. Existing of thrust faults caused to pressure, tectonic uplift and V shape valleys in western and north eastern part of study area.
    Keywords: Tectonic uplift, morphotectonic analysis, Geomorphic indices, Shekarab Mountain, East of Iran
  • Mojtaba yamani, ebrahim moghimi, abolghasem goorabi, seyed mohammad Zamanzadeh, * abotaleb mohamadi Pages 196-215
    One of the most important structural factors in the formation of volcanoes and molten materials is their formation. Volcanic eruptions cause deformation of morphology and the creation of a new landform. Damavand volcano has made significant changes around its quaternary as a complication with its successive eruptions. In this research, the role of Damavand lava in the creation of dam lakes has been investigated. To achieve this goal, the analytical method and the timing of the change have been applied.The technique of comparing the morphometry of lagoons and lava dams is based on three ways of comparing the height and thickness of alluvial deposits, determining the extent of spreading of sediments of the lakes, and the restoration of the last elevation of lavaes overlooking the valleys. Lake Haraz, at 2550 meters and with an area of ​​54/44 square kilometers, lar lake is located at a height of 2580 meters with an area of ​​68/79 and Dilichai lake at an altitude of 3780 meters above sea level, with an area of ​​25 square kilometers. These three lakes are formed almost simultaneously. The lava streams of these three lakes are separated and consecutively put together. The lakes are connected through the swells, which led to the formation of the current duct.
    Keywords: Damavand, lake dam, lake paradise, ancient geomorphology
  • Leila Amini, *Ataollah Abdollahi Kakroodi Pages 216-230

    Remote sensing method known an appropriate tool for estimating depth in the coastal environment of the limited reaches. The purpose of this study is to measure the depth of the southeastern coast of the Caspian Sea through the training of the neural network. In order to estimate depth, Landsat-8 images and hydrographic data collected using the echosounder, have been used. Atmospheric correction of Dark Object Subtract (DOS), radiometric correction (turning digital number to reflection), the sun glint correction, and eventually masking the water body from the land area, applied on the coastal blue, blue, green and red bands. These steps known as pre-processing.
    In this study, depth estimation through the neural network is investigated in two states. In the first case, each of the four bands as input and real depth corresponding to each of these pixels as target was introduced to the neural network. In the second case, the depth data were clustered to seven clusters by the fuzzy C-mean (FCM) method. After clustering, the data of each cluster was separately presented to the network. In both cases, the share of train data, validation data and test data from input data is 60%, 10% and 30%, respectively. The results of the neural network indicate that the accuracy of the estimated depth in various clusters is different, and the highest accuracy (R2 = 0.90, RMSE= 0.11) and the lowest accuracy (R2 = 0.67, RMSE= 0.11) belong to cluster (1) and cluster (3) respectively. As well as, the estimated depth in no clustered data, evaluated with high accuracy )R2 = 0.98, RMSE = 0.16).Then, neural network method is able to estimate depth from shallow coastal waters with high accuracy.
    Keywords: Bathymetry, Landsat-8, Fuzzy Clustering, Neural network, southeastern of Caspian Sea
  • mansor parvin* Pages 231-244
     
    Introduction
    Urbanization is one of the major challenges of the contemporary world, and at least 0.5% of the land area is found in cities (Schneider et al., 2009, 2).Urban development as a human category occurs in the context of geomorphology.Therefore, urban geomorphology, in addition to studying geomorphic limitations in urban development (Kuek, 1984, 22), the suitability of landforms for urban use, the impact of urban activities on land surface processes and landforms created by urbanization Is evaluated and studied (Douglas & James, 2015, 52).The city of Kermanshah is located in Kermanshah Navidese plain in terms of geomorphology and is composed of different landforms.Each of these landforms plays an important role in urban development.Also, urban development has had a great impact on geomorphologic landforms and so far no studies have been carried out in these areas within the city of Kermanshah.Considering the specific geomorphological conditions of the city of Kermanshah and its risks, recognizing the interactions between geomorphology and urban development on each other will play an important role in the planning and management of Kermanshah.The purpose of this research is to evaluate the effects of geomorphology on the urban development of Kermanshah over a period of 40 years.It is impossible to achieve this without the availability of suitable data.
    materials and methods
    In the present study, library, historical, cartographic and remote sensing methods are used.Map of geomorphologic complications of the city and surrounding areas of Kermanshah is based on the analysis of the land systems.Then, the extent and directions of physical development of Kermanshah city are determined during 40 years in selected years of 1977, 1986, 1996, 2006, and 2017 using Landsat satellite satellite imagery, MSS, TM and OLI.The supervised classification method has the maximum probability and selection of educational samples based on visual interpretation, false color combinations, and land surveys to determine the city's boundaries.Then, by mapping the map of geomorphologic complications with Kermanshah districts in selected years, the city's developmental extent in each of the geomorphologic traits has been determined and changes in the geomorphologic complications caused by the expansion of the city are also estimated.

    Findings
    The increase in the area of Kermanshah in the 40-year period has been around 5.5 times. Alluvial plain land has the largest area for the remainder of the year except for 1977 and has been affected by increasing area in all years. Alluvial fan landforms, hillside plains and regular slope have a upward trend in terms of area and area during 5 years, which suggests the development of a city in the territory of these landforms.The land flood plain has increased in terms of area, and the two hills and the irregular slopes have a limited area and have been located in urban areas only in the last two years.In Kermanshah, urban development has been affected by the existence of alluvial plain land so that the most development on this landform is in northern, northwest, northeast, western and eastern directions.The physical expansion of the city of Kermanshah has had an impact on the geomorphological prospects of Kermanshah plain.Alluvial plain landforms, flood plains alluvial fan rivers and river valleys have become urban landscapes.The subterranean rivers of the waterfall and Cham Bashir have become narrow underground channels and are no longer visible on the surface of the earth, and the development of their substrate has been stopped.
    Conclusion
    Landforms of geomorphology determine how urban development is.Alluvand plain landform has the largest role in this field and more than half of the area of Kermanshah is located on this landform.The three flat landforms of alluvial plain, alluvaih fan and hillside plains account for 72% of the total area of the city of Kermanshah in 2017.The plain landform, the old town nucleus, is about 16% of the city's total area.The limiting or hazardous landforms of the flood plain, regular slopes, irregular slopes, river valleys and hill meadows account for about 12% of the area of the city of Kermanshah.The urban development of Kermanshah has had an impact on geomorphologic landforms and has led to significant changes and destruction of landforms.The drainage network of the region and Cham Bashir and Aashoran rivers have been completely destroyed, which could have adverse effects on water resources and residential areas around them.Other landforms such as alluvial plain, alluvial fan ,hillside plain and floodplain have become urban landscape and their evolutionary process has been stopped.Expansion of the city on hazardous landfills (flood plains) and limiting (irregular ranges, hill, etc.) in the future can lead to a risk to urban areas.
    Keywords: mansor parvin*, Geomorphology, Urban Development, Landform, Remote Sensing, Kermanshah City
  • Omid Rahimi, Fariba Esfandiary Darabad, Mehran Maghsoudi Pages 245-260
     
    Introduction
    During the last Quaternary period, the earth is affected by environmental changes and extreme climate fluctuations (Kaser and Osmaston, 2002). Environmental and climate changes during the last glacial maximum period from 26.5 to 19 kyr BP (Clark et al., 2009) have affected the landforms and paleoenvironments. Determining the equilibrium-line altitude is the best tool for the reconstruction of paleoclimate and paleoenvironment during former glaciations (Benn and Ballantyne, 2005, Lukas and Bradwell, 2010, Hughes et al., 2010). The Equilibrium Line Altitude (ELA) is the average elevation where, over a one-year time interval, accumulation equals ablation so the mass balance at this line is zero (Cogley et al., 2011). The purpose of this study was to reconstruction paleoclimate and paleoenvironment conditions during the last glacial maximum period using geomorphological evidence such as glacial landforms, including glacial cirques, Accumulation Area Ratio (AAR), Area-Altitude Balance Ratio (AABR) and Mean glacier elevation (MGE) or Kurowski methods at Chehel Cheshmeh mountains of Divandareh in Kurdistan province.
    Methodology
    In this research, after the field investigation of Chehel Cheshmeh Mountains, the glacier cirques of the region were identified. Then the position of the two typical cirques, including the Shahneshin, Qholizolikha Cirques and the three cirques located in Masjedmirza Mountains, along with the location of the moraines, was determined by using GPS. The geomorphology of the glaciers was mapped using a topographic map (1: 50000) and GPS data in the Freehand 9.0.2 and ArcGIS 10.4.1 software. Then, using DEM (12.5 m) and geomorphologic maps prepared in ArcGIS 10.4.1 software, the equilibrium line altitudes in the glaciers of Chehel Cheshmeh Mountains were calculated using the methods of the Accumulation Area Ratio (AAR), Area-Altitude Balance Ratio (AABR) and Mean glacier elevation (MGE) or Kurowski (Pellitero et al., 2015). The method of Lai (2003) was used to estimate the present equilibrium-line altitude in Chehel Cheshmeh Mountains. In order to calculate the present equilibrium-line altitude, the temperature and precipitation data from the meteorological stations around the study area were used.
    Discussion
    Based on the mean glacier elevation method, the equilibrium-line altitude during the last glacial maximum in the Shahneshin is 2812.5 (m.a.s.l), in Qolizolikha 3027.5 (m.a.s.l) and in the Masjedmirza is 2868 (m.a.s.l). Based on the area-altitude balance ratio, the equilibrium-line altitude during the last glacial maximum in the Shahneshin is 2827 (m.a.s.l), in Qolizolikha 3018 (m.a.s.l) and in the Masjedmirza is 2869 (m.a.s.l). Using the method of Lai et al. (2003) and using the meteorological data, the present equilibrium-line altitude of the Zarineh station was 4735 m, Baneh station was 4680 m. Sanandaj station was 4633 m, the average of three stations located in the region of the study area was 4683 (m.a.s.l).
    Conclusion
    The equilibrium-line altitude during the last glacial maximum was calculated about 2905 (m.a.s.l) at the Chehel Cheshmeh Mountains. The present equilibrium-line altitude was estimated about 4683 (m.a.s.l) using Lai Method and the use of meteorological data. With Consideration of the equilibrium-line altitude lowering about 1778 meters, the mean annual temperature drop was around 11.5° during the last glacial maximum. Compared to other studies by Wright et al (1962, 2004) the temperature drop in the glacial mountains of Kurdistan 12 ° C, Bobek (1937) in the glacial mountains of Kurdistan 4 ° C, Bobek (1963) in the Alborz and Zagros Mountains from 4°C to 5°C, Krinsley (1970) in Playas and deserts in central Iran from 5°C to 8°C, Frenzel et al (1992) in the Northern hemisphere from 10°C to 12°C, Seif (2015) in Oshtorankuh 9.8°C, Kuhle (2008) in the Kuh-i-Jupar 10.5°C, Yamani et al (2007) in the Karkas Mountains from 10°C to 12°C, and Jafari et al (1396) in the mountains of Ghorveh 8.8°C were observed. Also, according to previous studies, the rate of equilibrium-line altitude lowering the glacial mountains of Kurdistan by Wright et al. (1962, 2004) between 1200 to 1800 m, Bobek (1937) in the glacial mountains of Kurdistan 700 m, Bobek (1963) in the Alborz and Zagros Mountains 600-800 m, Krinsley (1970) in Playas and deserts in central Iran more than 1,800, Seif (2015) in Oshtorankuh more than 1380 m, Kuhle (2008) in the Kuh-i-Jupar 1500 m are estimated. By comparing the equilibrium-line altitude lowering and the rate of reduction in the calculated temperature with other studies in Iran and the world, the last glacial maximum at Chehel Cheshmeh Mountains corresponds to the last glacial maximum about 26.5 to 19 kyr BP. It was affected by cold and dry climate conditions. Therefore, the use of glacier geomorphologic evidence and the equilibrium-line altitude are very suitable methods for the reconstruction of the environment and paleoclimate in Chehel Cheshmeh Mountains Divandarreh, Kurdistan, during the last glacial maximum.
    Keywords: The last glacial maximum (LGM), Equilibrium-line altitude (ELA), Area-Altitude Balance Ratio (AABR), Chehel Cheshmeh Mountains
    Keywords: The last glacial maximum (LGM), Equilibrium-line altitude (ELA), Area-Altitude Balance Ratio (AABR), Chehel Cheshmeh Mountains