Limestone compaction: an enigma

Compression of an undisturbed carbonate sediment core under a pressure of 556 kg/cm² produced a “rock” with sedimentary structures similar to typical ancient fine-grained limestones. Surprisingly, shells, foraminifera, and other fossils were not noticeably crushed, which indicates that absence of crushed fossils in ancient limestones can no longer be considered evidence that limestones do not compact.