SQUIDA SQUID (superconducting quantum interference device) is a very sensitive magnetometer used to measure extremely weak magnetic fields, based on superconducting loops containing Josephson junctions. SQUIDs are sensitive enough to measure magnetic fields as low as 5×10 T with a few days of averaged measurements (see orders of magnitude (magnetic field)). Their noise levels are as low as 3 fT·Hz.
CephalopodA cephalopod is any member of the molluscan class Cephalopoda (Greek plural κεφαλόποδες, kephalópodes; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles (muscular hydrostats) modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt ink.
PhragmoconeThe phragmocone is the chambered portion of the shell of a cephalopod. It is divided by septa into camerae. In most nautiloids and ammonoids, the phragmocone is a long, straight, curved, or coiled structure, in which the camerae are linked by a siphuncle which determines buoyancy by means of gas exchange. Despite this benefit, such a large shell adds to the mass of the animal, and hence is disadvantageous in catching fast-moving prey.
Late TriassicSubdivision of the Triassic according to the ICS, as of 2024.Vertical axis scale: Millions of years agoEtymologyChronostratigraphic nameUpper TriassicGeochronological nameLate TriassicName formalityFormalUsage informationCelestial bodyEarthRegional usageGlobal (ICS)Time scale(s) usedICS Time ScaleDefinitionChronological unitEpochStratigraphic unitSeriesTime span formalityFormalLower boundary definitionFAD of the AmmoniteLower boundary GSSP, Dolomites, Italy46°31′37″N11°55′49″E / 46.5269°N 11.9303°E / 46.5269; 11.9303Lower GSSP ratified2008Upper boundary definitionFAD of the Ammonite Psiloceras spelae tirolicumUpper boundary GSSPKuhjoch section, Karwendel mountains, Northern Calcareous Alps, Austria47°29′02″N11°31′50″E / 47.4839°N 11.5306°E / 47.4839; 11.5306Upper GSSP ratified2010The Late Triassic is the third and final epoch of the TriassicPeriod in the geologic time scale, spanning the time between 237 Ma and 201.4 Ma (million years ago).
EoceneThe Eocene (IPA: EE-ə-seen, EE-oh-) is a geological epoch that began about 56 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The end point of the Eocene is the Eocene-Oligocene transition (EOT), between 33.9 and 33.4 Ma. Precise boundaries between the epochs are sometimes given at 33.9 or 33.7 Ma. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch.
Late CretaceousSubdivision of the Cretaceous according to the ICS, as of 2024.Vertical axis scale: Millions of years agoEtymologyChronostratigraphic nameUpper CretaceousGeochronological nameLate CretaceousName formalityFormalUsage informationCelestial bodyEarthRegional usageGlobal (ICS)Time scale(s) usedICS Time ScaleDefinitionChronological unitEpochStratigraphic unitSeriesTime span formalityFormalLower boundary definitionFAD of the Planktonic ForaminiferRotalipora globotruncanoidesLower boundary GSSPMont Risoux, Hautes-Alpes, France44°23′33″N5°30′43″E / 44.3925°N 5.5119°E / 44.3925; 5.5119Lower GSSP ratified2002Upper boundary definitionIridium enriched layer associated with a major meteorite impact and subsequent K-Pg extinction eventUpper boundary GSSPEl Kef Section, El Kef, Tunisia36°09′13″N8°38′55″E / 36.1537°N 8.6486°E / 36.1537; 8.6486Upper GSSP ratified1991The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the CretaceousPeriod is divided in the geologic time scale.Littoral zoneThe littoral zone, also called litoral or nearshore, is the part of an ocean, sea, lake, or river, that is close to the shore. It provides extensive and productive habitats around the world, adjacent to land-water interfaces. In coastal ecology, the littoral zone includes the foreshore (intertidal zone) extending from the high water mark (which is rarely inundated) to the low water mark (where coastal areas become permanently submerged).
ChitinChitin (C8H13O5N)n ( ) is a long-chain polymer of N-acetylglucosamine, an amide derivative of glucose. Chitin is the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chitin are produced each year in the biosphere.
CalciteCalcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on the Mohs scale of mineral hardness, based on scratch hardness comparison. Large calcite crystals are used in optical equipment, and limestone composed mostly of calcite has numerous uses. Other polymorphs of calcium carbonate are the minerals aragonite and vaterite.
MegateuthisMegateuthis is the largest known belemnite genus which lived during the Early to Middle Jurassic, between the Toarcian and Bajocian age. The type speciesM. suevica, whose junior synonym is M. gigantea, measured around 2.17 metres (7.1 ft) long, and the largest species M. elliptica possibly reached up to 3.11 metres (10.2 ft) long.
Pelagic zoneThe pelagic zone consists of the water column of the open ocean and can be further divided into regions by depth. The word pelagic is derived from Ancient Greek (pélagos)'open sea'. The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom.
Triassic–Jurassic extinctionThe Triassic–Jurassic (Tr-J) extinction event, often called the Triassic–Jurassic mass extinction (TJME) or end-Triassic extinction, marks the boundary between the Triassic and Jurassic periods, 201.4 million years ago. It represents one of five major extinction events during the Phanerozoic, profoundly affecting life on land and in the oceans.
ExtinctionTermination of a species' lineageThe thylacine (Thylacinus cynocephalus) is an example of a recently extinct species.Palaeotherium is an example of an extinct genus that is only recorded from fossil records before the existence of hominids.Extinction is the termination of a species via the death of its last member. A taxon may become functionally extinct before the death of its last member if it loses the capacity to reproduce and recover.*As an Amazon Associate I earn from qualifying purchases.