GEOLOGY

Detailed explanation-1: -It is defined as the ratio between the basin perimeter and the circumference of a circle with a surface equal to the basin area. This coefficient is 1 for an ideally circular watershed and increases with both basin elongation and irregularity of basin boundaries (Fig.

Detailed explanation-2: -The watershed area and the volume of water that drains from it relates directly to the size and flow of the primary stream or water body. Other factors that make each watershed distinctive include its mosaic of land uses, soil types, geology, topography, and climate.

Detailed explanation-3: -The shape, or topography, of the land surface determines the size of a surface watershed. Surface watersheds can be outlined on maps that show land contours. Fairly accurate watershed boundaries can be drawn using 7.5 minute topographic maps.

Detailed explanation-4: -In general, river basins are shaped by rainfall, which erodes the land as it drains down into a river or stream. In humid environments, a large fraction of rainfall seeps into the Earth, creating a water table, or a local reservoir of groundwater.

Detailed explanation-5: -A dendritic drainage pattern is the most common form and looks like the branching pattern of tree roots. It develops in regions underlain by homogeneous material. That is, the subsurface geology has a similar resistance to weathering so there is no apparent control over the direction the tributaries take.