The Ordovician in Massachusetts, US

Paleontology and geology

Ordovician rocks are fairly common in Massachusetts, occurring in several broad north-south bands through the central part of the state and in the far northwest. Evidence from these rocks indicates that this area lay near the equator and, though at the edge of the continent, the area was fully marine. Thick layers of limy and muddy sediments were deposited on the ancient sea floor. Volcanic activity contributed abundant ash and lavas to the region. Metamorphism during the several Paleozoic mountain-building events severely altered Ordovician rocks, particularly in the eastern part of the state. As a consequence, few Ordovician fossils are known from Massachusetts.