Complex sentence: Well known greensands are the Upper and Lower Greensands of England and occur within Eocene and Cretaceous sedimentary strata underlying the coastal plains of New Jersey and Delaware.
Split into simpler sentences: Well known greensands are the Upper and Lower Greensands of England. They are also a prominent part of Cretaceous and Eocene sedimentary strata underlying the coastal plains of New Jersey and Delaware.