What characteristics from the earth cause its plates to move?

Plz hury on a timer which statements explain what happens at deep-ocean trenches? check all that apply. crust is formed. mountains are formed. seafloor spreading occurs. crust becomes molten rock. denser plates slide under lighter plates.

After world war i, how did the us economy compare to that of germany?

Ageologist is working in an area with exposed sedimentary rocks and finds a well exposed sequence of stratified rocks. as he works through a thick sequence of limestone, he sees abundant large clam fossils that produce an interlocking texture suggesting a reef, but within the limestone section these clams disappear and the overlying limestone is made up primarily of fragments of corals. he now moves 50 km away and finds limestones interbedded with shales, and the limestones contain the same clam fossils he had seen previously 50 km away. as he continues through this section, the rocks become entirely limestone, and the clams disappear again with coral fossils above forming a reef structure. he concludes