contestada

You come across a thick deposit of shale that forms a layer in the ground. What can you infer about the area's past environment?

A. It was near a volcano, because shale forms when lava cools quickly and hardens.
B. It was covered by water, because shale forms when water deposits clay particles.
C. It was underground in a volcanic area, because shale forms when magma cools slowly and hardens.
D. It was covered by water, because shale forms when water evaporates and deposits the dissolved clay.

Respuesta :

D is the answer as shale are deposited in slow moving water and are often found in river deltas,on flood plains and offshore from beach sands. They can also be deposited in sedimentary basins and on the continental shelf, in relatively deep and quiet water.