About 90,900 results
Open links in new tab
  1. Coquina - Wikipedia

    Coquina (/ k oʊ ˈ k iː n ə /) is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically sorted fragments of mollusks, trilobites, brachiopods, or other invertebrates.

  2. Coquina - The Rock that Saved St Augustine - Castillo de San …

    Mar 19, 2018 · Who would think that a fort made out of seashells would last three days under cannon fire? But the Castillo de San Marcos, made of local coquina stone, did just that. What exactly is this strange rock? How was it formed, and where did it come from? And how did this rock shape the history of St. Augustine? How Coquina is Formed

  3. Coquina: Limestone composed almost entirely of fossil debris - Geology.com

    What Is Coquina? Coquina is a sedimentary rock composed almost entirely of sand-size fossil debris. The fossils are usually mollusk or gastropod shells and shell fragments. Brachiopod, trilobite, coral, ostracod and other invertebrate shell debris is present in many coquinas.

  4. Coquina | Sedimentary Rock, Shells & Fossils | Britannica

    coquina, limestone formed almost entirely of sorted and cemented fossil debris, most commonly coarse shells and shell fragments. Microcoquinas are similar sedimentary rocks that are composed of finer material.

  5. What are coquina and tabby? - NOAA's National Ocean Service

    Jun 16, 2024 · Coquina is a rare form of limestone composed of the shell fragments of ancient mollusks and other marine invertebrates, which, over time, are glued together by dissolved calcium carbonate in the shells. Coquina is also the name of a common tiny clam found everywhere on Florida beaches.

  6. Coquina: Identification, Pictures & Info for Rockhounds

    Coquina is a clastic sedimentary rock made almost entirely out of large (2 mm or larger) shell fragments. The shell fragments are cemented together by calcite, and it is technically a variety of limestone. Coquina forms almost exclusively in high-energy marine environments like beaches and tidal channels.

  7. Coquina - Sedimentary Rocks - Sandatlas

    Coquina is a detrital limestone consisting of shells or shell fragments. The constituents are mechanically sorted (usually by sea waves), transported and often abraded because of transport and sorting.

  8. Coquina – Sedimentary Rock Definition and Composition

    Feb 28, 2019 · What type of rock is coquina? Coquina is a type of sedimentary rock that is primarily composed of fragmented shell debris. The shells that make up coquina can come from a variety of marine animals, such as clams, snails, and other shellfish.

  9. What Is Coquina | Coquina Features - Compare Nature

    Coquina is a sedimentary rock which is formed when billions of small clam-like seashell, called Coquina, or cockleshell are die and hence are deposited, buried and turns into a rock when pressure is applied.

  10. Coquina Rock Definition, Formation & Characteristics - Study.com

    Coquina is a very porous rock with a granular texture and a light color. It is most commonly used as a groundwater aquifer or a reservoir for oil and natural gas.

Refresh