The quarries at UC Santa Cruz remain from the late 1800's when marble was mined for its lime to make mortar, plaster, and cement. The sheer cliffs seen in these photographs remains from use of explosives to extract the marble from these quarries. The marble of the UC Santa Cruz campus is part of a group of metamorphic and plutonic rocks called the Salinian Block. These rocks are located west of the San Andreas Fault and are sliding northward along coastal California as part of the Pacific Plate. There are many different types of limestone, but most are composed entirely of the shells or hard parts of marine organisms.
Limestone usually forms in warm shallow seas, where many types of organisms live.
Coral reefs, for example, build up layers of coral skeletans that eventually turn into limestone. Old volcanoes like Tahiti or Bora Bora in the South pacific form common nucleation points. After limestone formation, tectonic forces took these particular rocks to high temperatures and pressures deep within the Earth, and turned them into metamophic rocks. The limestones turned into marble while the the pelitic rocks turned into schists and gniesses. During metamorphism, nearly all original sedimentary structures were obliterated.