Ahydrograph depicts changing discharge of a river through time. a) true b) false an unconfined aquifer is overlain by a confining layer: a) true b) false greenstone belts are ancient oceanic crust. a) true b) false

A. True,  A.  True A. True

Explanation:

Hydrograph shows the rate of flow of water versus time from a river, a canal that is carrying the flow. A hydrograph can be for Surface runoff, Storms and floods.

An aquifer is a body of rock that has permissible water retention capacity. I t may be defined as confined or unconfined if it's confined it may have a layer above it.

The concept of greenstone belt has originated from the ancient oceanic spreading centers, and Icelandic arc terrains formed by basaltic rocks.