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Geology

Structural geology

Geologic features

Flat area on the deep ocean floor

A rock that is among the oldest known crustal fragments on Earth

Accretionary wedge

The sediments accreted onto the non-subducting tectonic plate at a convergent plate boundary

A major tectonic plate underlying Africa west of the East African Rift

The increase in land elevation due of the deposition of sediment

Mineral, Na-feldspar, Na-silicate, tectosilicate

Algoman orogeny

Late Archaean episode of mountain building in what is now North America

Loose soil or sediment that is eroded and redeposited in a non-marine setting

Group of inosilicate minerals

A metamorphic rock containing mainly amphibole and plagioclase

Nesosilicate mineral

Ongoing mountain-forming process in South America

Type of volcanic rock

Calcium-rich feldspar mineral

Antarctic plate

A tectonic plate containing the continent of Antarctica and extending outward under the surrounding oceans

In geology, an anticline is a type of fold that is an arch-like shape

Mineral group, calcium phosphate

A minor tectonic plate consisting mostly of the Arabian Peninsula, extending northward to Mesopotamia and the Levant

Calcium carbonate polymorph

Carcinogenic fibrous silicate mineral

The highly viscous, mechanically weak and ductile region of Earth's mantle

Pyroxene mineral

Submarine features associated with island arcs and subduction zones

Banded iron formation

Layered iron-rich sedimentary rock

Sulfate mineral

A magnesium- and iron-rich extrusive igneous rock

Basement (geology)

Metamorphic or igneous rocks below a sedimentary platform or cover

Large igneous rock intrusion

Sedimentary rock rich in aluminium

Stratigraphic subdivison

Particles in a flowing fluid that are transported along the bed

Result of bed material being moved by fluid flow

Belt Supergroup

Group of Mesoproterozoic sedimentary rocks

Gemstone: beryllium aluminium cyclosilicate

Biostratigraphy

Stratigraphy which assigns ages of rock strata by using fossils

Group of minerals

Reworking of soils and sediments by organisms.

Rank of biostratigraphic unit

A metavolcanic rock that forms by the metamorphism of basalt and rocks with similar composition

Structures in rock caused by extension

Natural rock fragment larger than 25.6 centimetres in diameter

Bowen's reaction series

Order of crystallization of minerals in magma

Rock composed of broken fragments cemented by a matrix

Brittle–ductile transition zone

The strongest part of the Earth's crust

Carbonate mineral and polymorph of calcium carbonate

Cauldron-like volcanic feature formed by the emptying of a magma chamber

Carbonate mineral

Minerals in which CO3 and NO3 are the main anion

Class of sedimentary rock

Caribbean plate

A mostly oceanic tectonic plate including part of Central America and the Caribbean Sea

Rock formed by fracturing and comminution during faulting

Cementation (geology)

Process of chemical precipitation bonding sedimentary grains

Central Asian Orogenic Belt

Phanerozoic accretionary orogen

Copper iron sulfide mineral

Phyllosilicates: non-swelling 2:1 clay (TOT) whose interlayer is occupied by a brucite, Mg(OH)2, bridge

Chronostratigraphy

Study of relative time relations and ages of rock layers

A steep conical hill of loose pyroclastic fragments around a volcanic vent

Red mercury sulfide mineral

Sedimentary rocks made of mineral or rock fragments

A finely-grained natural rock or soil containing mainly clay minerals

Hydrous aluminium phyllosilicates

Cleavage (geology)

Structural geology

Cobble (geology)

A rock larger than a pebble and smaller than a boulder

Young oceanic tectonic plate beneath the Pacific Ocean off the west coast of Central America

Columbia River Basalt Group

Continental flood basalt province in the Western United States

Complex volcano

Landform of more than one related volcanic centre

Conglomerate (geology)

A coarse-grained clastic sedimentary rock with mainly rounded to subangular clasts

Contact (geology)

Boundary between geologic units

Very large landmass identified by convention

Continental crust

Layer of rock that forms the continents and continental shelves

Continental drift

The movement of the Earth's continents relative to each other

Continental fragment

Part of a continent broken from its main mass

Continental margin

Zone of the ocean floor that separates the thin oceanic crust from thick continental crust

Continental rise

An underwater feature connecting the continental slope and the abyssal plain

Continental shelf

A portion of a continent that is submerged under an area of relatively shallow water known as a shelf sea

Convergent boundary

Region of active deformation between colliding tectonic plates

Cylindrical section of a naturally occurring substance, usually obtained by drilling into it with special drills

Old and stable part of the continental lithosphere

Cratonic sequence

A very large-scale lithostratographic sequence that covers a complete marine transgressive-regressive cycle across a craton

Texture of metamorphic rock by deformation

Cretaceous–Paleogene boundary

Geological signature marking the boundary between the end of the Cretaceous Period and the beginning of the Paleogene Period

Sedimentary rock strata at differing angles.

Crust (geology)

The outermost solid shell of a rocky planet, dwarf planet, or natural satellite

Mineral discovered and named after its place of discovery, Cummington, Massachusetts

Volcanic rock intermediate in composition between andesite and rhyolite

A large igneous province located on the Deccan Plateau

Geological feature

Degradation (geology)

Lowering of a fluvial surface, such as a stream bed or floodplain, through erosional processes

Deposition (geology)

Geological process in which sediments, soil and rocks are added to a landform or landmass

Detachment fault

Geological term associated with large displacements

Physico-chemical changes in sediments occurring after their deposition

A type of geologic intrusion in which a more mobile and ductily deformable material is forced into brittle overlying rocks

A sheet of rock that is formed in a fracture of a pre-existing rock body

Pyroxene mineral

Intermediate intrusive igneous rock composed principally of plagioclase feldspar

Divergent boundary

Linear feature that exists between two tectonic plates that are moving away from each other

Dolomite (rock)

Sedimentary carbonate rock that contains a high percentage of the mineral dolomite

Ductility (Earth science)

Green gemstone, a beryl variety

Pyroxene: magnesium-iron silicate with MgSiO3 and FeSiO3 end-members

Sorosilicate mineral

A tectonic plate which includes most of the continent of Eurasia

A water-soluble mineral sediment formed by evaporation from an aqueous solution

Igneous rock formed when magma emerges above the Earth's surface before cooling

Fabric (geology)

Spatial and geometric configuration of all the elements that make up a rock

Manifestation of character, reflecting conditions of origin of rock strata

An ancient oceanic plate that has mostly subducted under the west coast of the North American Plate

Fault (geology)

Fracture or discontinuity in rock across which there has been displacement

Olivine, nesosilicate mineral

A group of rock-forming tectosilicate minerals

The result of a very large volume eruption of basalt lava

Mineral form of calcium fluoride

Stack of originally planar surfaces

Foliation (geology)

Repetitive layering in metamorphic rocks

The region between an oceanic trench and the associated volcanic arc

A structural basin that develops adjacent and parallel to a mountain belt

Olivine, nesosilicate mineral

Fracture (geology)

Geologic structure

A coarse-grained mafic intrusive rock

Natural mineral form of lead sulfide

Mineral, semi-precious stone

Gemstone (disambiguation)

Topics referred to by the same term

Geologic province

A spatial entity with common geologic attributes

Geologic record

Entirety of the layers of rock strata

Geological formation

The fundamental unit of lithostratigraphy

Study of the composition, structure, physical properties, and history of Earth's components and processes

Geology of the Himalayas

Origins and structure of the mountain range

Natural explosive eruption of hot water

A common high-grade metamorphic rock

Type of layering in sediment or sedimentary rock

Diameter of individual grains of sediment, or of lithified particles in clastic rocks

Common type of intrusive, felsic, igneous rock with granular structure

Type of coarse grained intrusive igneous rock

A class of high-grade medium to coarse grained metamorphic rocks

Mix of crumbled stones: grain size range between 2 – 63 mm according to ISO 14688

Metamorphic rock formed in temperatures of 300–450 °C and pressures of 2–10 hPa, with an abundance of green minerals (e.g. chlorite, serpentine, epidote) and platy minerals (muscovite, serpentine)

Greenstone belt

Zone of variably metamorphosed rocks occurring in Archaean and Proterozoic cratons

A hard, dark sandstone with poorly sorted angular grains in a compact, clay-fine matrix

Group (stratigraphy)

A group of geologic formations

Soft calcium sulfate mineral

Nickel–Strunz 9 ed mineral class number 3

Mineral form of sodium chloride

Volcanic hotspot located near the Hawaiian Islands, in the northern Pacific Ocean

Pyroxene mineral

Common iron oxide mineral

A complex inosilicate series of minerals

Series of contact metamorphic rocks that have been baked and indurated by the heat of intrusive igneous masses.

Horst and graben

Topography consisting of alternating raised and lowered fault blocks

Hotspot (geology)

Volcanic regions thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle

Hummocky cross-stratification

Sedimentary structure found in sandstones

Hydrothermal vent

A fissure in a planet's surface from which geothermally heated water issues

Rock formed through the cooling and solidification of magma or lava

Titanium-iron oxide mineral

Indo-Australian plate

A major tectonic plate formed by the fusion of the Indian and Australian plates

Magmatic rock formed below the surface

Magmatic rock formed below the surface

Sedimentary rock

Ornamental stone, commonly green

Joint (geology)

Geological term for a type of fracture in rock

Juan de Fuca plate

A small tectonic plate in the eastern North Pacific

An ultramafic mantle-derived volcanic rock

Aluminosilicate mineral

Violent type of mudflow or debris flow from a volcano

Lamination (geology)

Layering structure in sedimentary rocks usually less than 1 cm in thickness

Metamorphic rock containing lazurite, prized for its intense blue color

Laramide orogeny

Period of mountain building in North America

Large igneous province

Huge regional accumulation of igneous rocks

Molten rock expelled by a volcano during an eruption

Large, mostly flat area of lava flows

Law of superposition

In undeformed stratigraphic sequences, the oldest strata will be at the bottom of the sequence

Sedimentary rocks made of calcium carbonate

Lineation (geology)

A descriptive and nongenetic term for any kind of linear structure within or on a rock

List of index fossils

Fossils used to define and identity geologic periods

The rigid, outermost shell of a terrestrial-type planet or natural satellite that is defined by its rigid mechanical properties

Lithostratigraphy

Method of establishing stratigraphical units

Local regression

Moving average and polynomial regression method for smoothing data

The region from 660 to 2900 km below Earth's surface

Low-relief volcanic crater

Natural material found beneath the surface of Earth

Accumulation of molten rock within the Earth's crust

Iron ore mineral

Magnetostratigraphy

Method of dating sedimentary and volcanic rocks

Non-foliated, metamorphic rock, commonly used for sculpture and as a building material

Marine regression

A geological process of areas of submerged seafloor being exposed above the sea level.

Marine transgression

Geologic event in which sea level rises relative to the land

Metamorphic rock

Rock that was subjected to heat and pressure

Solid debris from outer space that hits a planetary surface

Group of phyllosilicate minerals

Feldspar, tectosilicate mineral

Mid-ocean ridge

Basaltic underwater mountain system formed by plate tectonic spreading

A mixture of metamorphic rock and igneous rock

Element or chemical compound that is normally crystalline formed as a result of geological processes

Element or chemical compound that is normally crystalline formed as a result of geological processes

Mineral physics

The science of materials that compose the interior of planets

Scientific study of minerals and mineralised artifacts

Mixture of water and any combination of soil, silt, and clay

Sedimentary feature resulting from the drying of a clay-rich sediment

Class of fine grained siliciclastic sedimentary rocks

True mica, phyllosilicate mineral; polytypes: 1M, 2A, 2M2, 3T

Fine-grained, compact metamorphic rock produced by dynamic recrystallization of the constituent minerals

Mineral (as opposed to the chemical element)

Native element mineral

Elements that occur in nature as minerals in uncombined form

Oceanic tectonic plate in the eastern Pacific Ocean basin

North American plate

Large tectonic plate including most of North America, Greenland and part of Siberia.

Naturally occurring volcanic glass

The uppermost layer of the oceanic portion of a tectonic plate

Long and narrow depressions of the sea floor

Organic-rich fine-grained sedimentary rock containing kerogen

Magnesium iron silicate solid solution series mineral

Sedimentary rock formed from ooids

Rock with valuable metals, minerals and elements

The formation of mountain ranges

Tectosilicate mineral found in igneous rock

An oceanic tectonic plate under the Pacific Ocean

Concept of sequence stratigraphy

The transition between oceanic and continental lithosphere that is not an active plate margin

Sea level variations over geological time scales

Pebble (disambiguation)

Topics referred to by the same term

Pelagic red clay

Slow accumulating oceanic sediment with low biogenic constituents

Pelagic sediment

Fine-grained sediment that accumulates on the floor of the open ocean

A coarse-grained ultramafic igneous rock

The branch of geology that studies the origin, composition, distribution and structure of rocks

Philippine Sea plate

Oceanic tectonic plate to the east of the Philippines

Phosphate mineral

Nickel–Strunz 9 ed mineral class number 8 (isolated tetrahedral units, mainly)

Foliated metamorphic rock

Pyroxene mineral

Type of feldspar

Plate tectonics

Movement of the Earth's lithosphere

Ratio of void volume and total volume of a porous material

Pull-apart basin

A structural basin where two overlapping faults or a fault bend creates an area of crustal extension which causes the basin to subside

Light coloured highly vesicular volcanic rock

Iron (II) disulfide mineral

Pyroclastic flow

Fast-moving current of hot gas and volcanic matter that moves away from a volcano

Group of inosilicate minerals with single chains of silica tetrahedra

Mineral made of silicon and oxygen.

Hard, non-foliated metamorphic rock which was originally pure quartz sandstone

A layer of loose, heterogeneous superficial deposits covering solid rock

An igneous, volcanic rock, of felsic (silica-rich) composition

A proposed driving force for tectonic plate motion as the result of the lithosphere sliding down the raised asthenosphere below mid-ocean ridges

A linear zone where the Earth's crust is being pulled apart, and is an example of extensional tectonics

Wave structures created in sediments by bottom current

Naturally occurring mineral aggregate

Roundness (geology)

The smoothness of clastic particles

Variety of corundum, mineral, gemstone

Granular material composed of finely divided rock and mineral particles

Type of sedimentary rock

U.S. amateur radio satellite

Medium grade metamorphic rock with lamellar grain

Particulate solid matter that is deposited on the surface of land

Sediment gravity flow

Sediment transport mechanism

Sediment transport

The movement of solid particles, typically by gravity and fluid entrainment

Sedimentary basin

Regions of long-term subsidence creating space for infilling by sediments

Sedimentary basin analysis

Sedimentary rock

Rock formed by the deposition and subsequent cementation of material

Sedimentary structures

Geologic structures formed during sediment deposition

Sequence (geology)

Geological events, processes, or rocks, arranged in chronological order

Sequence stratigraphy

Study and analysis of groups of sedimentary deposits

Series (stratigraphy)

Sequence of rock depositions defining a chronostratigraphic unit corresponding to a specific epoch on the geologic time scale

Fine-grained, clastic sedimentary rock

Shear (geology)

In geology, the response of a rock to deformation usually by compressive stress

Structural discontinuity surface in the Earth's crust and upper mantle

Shield (geology)

A large stable area of exposed Precambrian crystalline rock

Low profile volcano usually formed almost entirely of fluid lava flows

A large region of volcanic rock in Russia

Carbonate mineral

Silicate mineral

Rock-forming minerals with predominantly silicate anions

Biogenic pelagic sediment located on the deep ocean floor

A tabular intrusion between older layers of rock

Nesosilicate mineral

Classification of soil or sediment

Sedimentary rock which has a grain size in the silt range

The portion of a tectonic plate that is being subducted

The part of the motion of a tectonic plate caused by its subduction

Metamorphic rock

An Archaean craton in the north-western Canadian Shield, in Northwest Territories and Nunavut

Soft-sediment deformation structures

Geologic formation

South American plate

Major tectonic plate which includes most of South America and a large part of the south Atlantic

Zinc-iron sulfide mineral

A mineral or gemstone

Stage (stratigraphy)

Unit in stratigraphy

Nesosilicate mineral

Stratigraphic section

Sequence of layers of rocks in the order they were deposited

Stratigraphic unit

Volume of rock defined by its petrographic, lithologic or paleontologic features

The study of rock layers and their formation

Type of conical volcano composed of layers of lava and tephra

Layer of sedimentary rock or soil with internally consistent characteristics

Orientation or attitude of a geologic feature

Structural basin

Geological depression

Structural geology

Science of the description and interpretation of deformation in the Earth's crust

A geological process at convergent tectonic plate boundaries where one plate moves under the other

Sulfate mineral

Class of minerals that include the sulfate ion

Sulfide mineral

Nickel–Strunz 9 ed mineral class number 2

Volcano that has erupted 1000 cubic km in a single eruption

Portion of sediment uplifted by a fluid's flow in the process of sediment transportation

Rocksalt group, halide mineral

Type of geological fold

System (stratigraphy)

A sequence of rock layers that were laid down in the same geological period

Topics referred to by the same term

Tectonic uplift

The portion of the total geologic uplift of the mean earth surface that is not attributable to an isostatic response to unloading

Terra Australis Orogen

A type of reverse fault that has a dip of 45 degrees or less

Unsorted glacial sediment

Topics referred to by the same term

Transform fault

Plate boundary where the motion is predominantly horizontal

Triple junction

The point where the boundaries of three tectonic plates meet

Rock consolidated from volcanic ash

The geologic deposit of a turbidity current

Type locality (geology)

Geologic term regarding rock types, stratigraphic units or mineral species

Distorted sediment deposition

Sheetlike body within a rock

Elements and compounds that are readily vaporized

Chain of volcanoes formed above a subducting plate

Landform of ejecta from a volcanic vent piled up in a conical shape

Rock formed from lava erupted from a volcano

Phenomena and processes associated with the action of volcanos, geysers and fumaroles

Volcano (1997 film)

1997 American film

The study of volcanoes, lava, magma and associated phenomena

Single chain calcium inosilicate (CaSiO3)

Yellowstone hotspot

Volcanic hotspot in the United States

Zirconium silicate, a mineral belonging to the group of nesosilicates