Maryland, US



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State Fossil:
State fossil from Maryland

Ecphora gardnerae gardnerae
This small snail lived in the warm, shallow waters off North America’s east coast during the Miocene (~ 12-5 million years ago), but went extinct ~ 2 million years ago. Ecphora preyed on other molluscs by boring into the shell to extract the animal inside.

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Paleontology and geology

The Precambrian: Precambrian rocks in Maryland are metamorphic and igneous. No fossils have been positively identified from these rocks thus far.

The Paleozoic: The Paleozoic in Maryland was a time of changing sea levels. Episodes of deposition in shallow seas were interrupted by mountain-building events and subsequent periods of erosion. Cambrian and Ordovician sedimentary rocks contain abundant marine fossils, indicating the presence of warm, shallow seas. A period of uplift and mountain building during the Late Ordovician was followed by a time of erosion and subsidence and the shallow seas returned. Two additional episodes of mountain building and subsequent erosion and subsidence followed, first in the Devonian and then at the end of the Paleozoic (Carboniferous and Permian). During times of subsidence, the seas returned and flooded the lands. These cycles of uplift and flooding led to alternating deposition of non-marine and marine sediments. Brachiopods and bryozoans were abundant in the sea, while horsetail rushes and scale trees thrived in the warm, humid, Late Paleozoic climate on land. Most of Maryland lay above sea level by the end of the Paleozoic.

The Mesozoic: Rift basins developed in Maryland during the early and middle Mesozoic as plate movement pulled apart the supercontinent of Pangea. Sediments washed into these valleys and accumulated as lake and river deposits. Fossils of plants and dinosaur footprints can be found in these rocks. Late in the Mesozoic (Cretaceous), seas advanced and retreated across the coastal plain numerous times, providing habitats that ranged from terrestrial to deep continental shelf. Fossils of plants and dinosaurs are common in the terrestrial deposits, while marine fossils include molluscs and brachiopods.

The Cenozoic: During the Early Cenozoic (Tertiary), sea level fluctuated in eastern Maryland, leaving marine deposits in the Chesapeake Bay region that are famous for their beautifully preserved fossils. The climate cooled later in the Cenozoic (Quaternary), and vast ice sheets advanced and retreated across North America. Although the ice sheets never reached Maryland, sea levels dropped as the glaciers expanded. The cooler temperatures encouraged the growth of new types of plants, while mastodons and other cold-adapted animals roamed the state. During warmer climate periods (interglacials), sea levels again rose to cover the eastern part of the state. Fossils of marine clams, oysters, and snails are abundant in the rocks formed during these interglacial episodes.

Links to more on Maryland paleontology

Organizations | Education and Exhibits | Research and Collections | Resources


Parks (showing 1 of 1 listings)

Calvert Cliffs State Park: This site has information on the fossils and rocks of the park, including maps, trail guides, activities, and events.

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Museums (showing 1 of 1 listings)

Calvert Marine Museum: This regionally-oriented museum highlights three maritime themes of the area: Miocene paleontology, modern estuarine life, and maritime history.

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Colleges and Universities (showing 1 of 1 listings)

The Center for Functional Anatomy and Evolution at Johns Hopkins University: Information on the faculty, students, and research at the Johns Hopkins Center for Functional Anatomy and Evolution. The primary research focus of the center is the exploration of relationships among the functional anatomy, behavior, and evolutionary biology of extant and extinct vertebrates.

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Government Agencies (showing 2 of 2 listings)

Maryland Geological Survey: Find information, maps, and publications on the geology and paleontology of Maryland.

Calvert Cliffs Fossils- Maryland Geological Survey: Hosted by the Maryland Geological Survey, this page and its links provide detailed information on the geology and fossils of the park, including fossil identification guides, references, maps, and publications.

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Education and Exhibits

Physical Exhibits (showing 1 of 1 listings)

Maryland Science Center Exhibits: This site details information on exhibits at the Maryland Science Center, including Dinosaur Mysteries (featuring a cast T. rex skeleton, models of Maryland's dinosaurs, and other exhibits), Fossil Quest, and TerraLink (highlighting geology and other earth sciences). 

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Research and Collections

Ongoing Research Projects (showing 1 of 1 listings)

The Ecphora, Calvert Marine Museum Fossil Club Newsletter: The Ecphora is a quarterly newsletter from the Calvert Marine Museum's Fossil Club. It features paleontology articles of general and specific interest on Miocene marine fossils, mostly. In addition to articles based on original research, this online publication includes news and happenings in paleontology at the museum, fossil club field trip schedules, and information about upcoming public lectures in paleontology at the Calvert Marine Museum.

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Curriculum and Classroom Resources (showing 1 of 1 listings)

Teacher-Friendly Guides to Geology: Provides teachers with an intuitive and jargon-free review of the geology of different regions of the United States. 

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