What is the marcellus shale, and why is it so important to ancient ocean life?

The Marcellus Shale also categorized as the Marcellus formation is a marine sedimentary rock unit of middle Devonian age found in eastern North America. It elongates throughout the major of the Appalachian Basin.  

The shale comprises huge unexploited reserves of natural gas, which makes it an attractive target for export and energy development. There are comparatively scarce presences of fossilized marine fauna found in the Marcellus, however, these fossils are still essential to paleontology.  

For example, the Marcellus comprises the primogenital known varied assemblage of thin-shelled mollusks, still possessing well-preserved shell microcomposition. It is also where goniatite, an extinct shelled swimmer identical to a squid, make their initial presence in the fossil record.  

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.

in addition to spreading humanist ideas, erasmus has contributed to criticism of corruption in the church.