Study of the hydro geomorphological characteristics of quaternary deposits in Jam Plain aquifer

Groundwater is a major source of water. The management of these resources is very important answer for increasing drinking, agricultural and industrial water demands. Management measures need knowing the spatial and temporal behavior of groundwater. According to anomalous use of groundwater resources in this region and considering floods due to precipitation regime with severe rainfall, there is a need to investigate Hydro-geomorphological characteristics of quaternary deposits of Jam Plain. In this research, exploration-geophysical surveys of quaternary deposits within the Jam Plain was investigated. For this purpose, graphical methods, geo-electric sections draw, and preparing iso-resistance to different depths maps, reviews exploratory piezometer wells drilled within the Jam Plain by drawing the logs through the provision of wells and subsurface levels between wells; and finally, hydro-geomorphology relations of quaternary deposits were studied. Results showed that the minimum alluvial depth starts from 30 m in north-western margin at a distance of 500 m east of Jam Forest Park and its maximum depth of 95 m is in the north-western margin of the aquifer and 450 m south of Mehrbagh oil and gas well. The highest hydraulic conductivity coefficient of 2.5 m/day in Jam Plain belongs to Gachi well and its minimum of 1.06 m/day is related to Faramarzi well. Investigating the trend of changes of hydraulic conductivity coefficient showed that its rate in the eastern part of the study area was 2-2.5 m/day and decreases to 1-1.5 m/day in the western parts and in the north to south direction it decreases from 2-2.5 to 1-1.5 m/day. The spatial trend of changes in the coefficient of transmission capacity from east to west to the middle of the plain is approximately constant and is located on the floor of 180-200 m2/day, but in western areas it has fallen to 50-90 m2/day. The changes of this coefficient showed no significant changes in the north to south direction till the middle of the plain. But, decreased in the southern parts, which is the result of the reduction of the thickness of alluvium in these areas. Results demonstrated that 4810, 2186 and 5282 ha of the study area belongs to mountainous, hill and plateau and the middle areas between the plains and the mountains units.