Godzareh depression
Encyclopedia
Afghanistan
Afghanistan , officially the Islamic Republic of Afghanistan, is a landlocked country located in the centre of Asia, forming South Asia, Central Asia and the Middle East. With a population of about 29 million, it has an area of , making it the 42nd most populous and 41st largest nation in the world...
and Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
known as the Sistan Basin
Sistan Basin
The Sistan Basin is an inland endorheic basin encompassing large parts of southwestern Afghanistan and southeastern Iran, one of the driest regions in the world and an area subjected to prolonged droughts...
. The Sistan Basin is an endorheic basin and encompasses a complex system of rivers, shallow lakes, marshes and wetlands as its watershed
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
, draining into the Hamun Lakes in southeastern Iran. Occasional outflows from these lakes are carried back into Afghanistan by the seasonal Shile river to the basin's terminus, the Godzareh depression in Afghanistan. The depression
Depression (geology)
A depression in geology is a landform sunken or depressed below the surrounding area. Depressions may be formed by various mechanisms.Structural or tectonic related:...
is flat and very shallow with fine textured sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
at its lowest portions. The lowest section of the Godzareh depression is 467 m above sea level. The depression only receives runoff
Surface runoff
Surface runoff is the water flow that occurs when soil is infiltrated to full capacity and excess water from rain, meltwater, or other sources flows over the land. This is a major component of the water cycle. Runoff that occurs on surfaces before reaching a channel is also called a nonpoint source...
water when the main tributaries are overflowing every 10 years on the average.
In general, a geological depression
Depression (geology)
A depression in geology is a landform sunken or depressed below the surrounding area. Depressions may be formed by various mechanisms.Structural or tectonic related:...
is a landform
Landform
A landform or physical feature in the earth sciences and geology sub-fields, comprises a geomorphological unit, and is largely defined by its surface form and location in the landscape, as part of the terrain, and as such, is typically an element of topography...
that is sunken or lower than the surrounding area. The Godzareh depression is the lowest point in the Sistan Basin in Afghanistan and therefore is the terminus to which all the water flows.