Marine sedimentMarine sediment, or ocean sediment, or seafloor sediment, are deposits of insoluble particles that have accumulated on the seafloor. These particles have their origins in soil and rocks and have been transported from the land to the sea, mainly by rivers but also by dust carried by wind and by the flow of glaciers into the sea. Additional deposits come from marine organisms and chemical precipitation in seawater, as well as from underwater volcanoes and meteorite debris.
Marine biogenic calcificationMarine biogenic calcification is the process by which marine organisms such as oysters and clams form calcium carbonate. Seawater is full of dissolved compounds, ions and nutrients that organisms can use for energy and, in the case of calcification, to build shells and outer structures. Calcifying organisms in the ocean include molluscs, foraminifera, coccolithophores, crustaceans, echinoderms such as sea urchins, and corals. The shells and skeletons produced from calcification have important functions for the physiology and ecology of the organisms that create them.
PāuaPāua is the Māori name given to three New Zealand species of large edible sea snails, marine gastropod molluscs which belong to the family Haliotidae (in which there is only one genus, Haliotis), known in the United States and Australia as abalone, and in the United Kingdom as ormer shells. Pāua has entered English through common use in the New Zealand English dialect, and is both singular and plural, following the grammar rules of its original language.
MineralogyMineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the processes of mineral origin and formation, classification of minerals, their geographical distribution, as well as their utilization. History of mineralogy Early writing on mineralogy, especially on gemstones, comes from ancient Babylonia, the ancient Greco-Roman world, ancient and medieval China, and Sanskrit texts from ancient India and the ancient Islamic world.
JurassicThe Jurassic (dʒʊˈræsɪk ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of the Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic Magmatic Province.
ChalkChalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Chalk is common throughout Western Europe, where deposits underlie parts of France, and steep cliffs are often seen where they meet the sea in places such as the Dover cliffs on the Kent coast of the English Channel.
RadulaThe radula (USˈrædʒʊlə; plural radulae or radulas) is an anatomical structure used by mollusks for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus. The radula is unique to the mollusks, and is found in every class of mollusk except the bivalves, which instead use cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs.
SpeciesIn biology, a species (: species) is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour, or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined.
GastropodaThe gastropods (ˈgæstrəpɒdz), commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (gæsˈtrɒpədə). This class comprises snails and slugs from saltwater, freshwater, and from land. There are many thousands of species of sea snails and slugs, as well as freshwater snails, freshwater limpets, and land snails and slugs. The class Gastropoda contains a vast total of named species, second only to the insects in overall number.
Shell USAShell USA, Inc. (formerly Shell Oil Company, Inc.) is the United States-based wholly owned subsidiary of Shell plc, a UK-based transnational corporation "oil major" which is amongst the largest oil companies in the world. Approximately 18,000 Shell employees are based in the U.S. Its U.S. headquarters are in Houston, Texas. Shell USA, including its consolidated companies and its share in equity companies, is one of America's largest oil and natural gas producers, natural gas marketers, fuel marketers and petrochemical manufacturers.
