Sedimentary Rocks
(limestone) oolitic
(close up) are whitish to cream-colored limestones composed of well rounded, sand-sized, concentrically-layered calcite grains called ______ . they form by rolling back and forth on a shallow seafloor (or on a lakebed) by wave action.
(limestone) oolitic
A limestone composed mainly of calcium carbonate "_______", small spheres formed by the concentric precipitation of calcium carbonate on a sand grain or shell fragment.
(limestone) crystalline
A limestone formed of abundant calcite crystals as a result of diagenesis; diagenesis is any chemical, physical, or biological change undergone by a sediment after its initial deposition and during and after its lithification, exclusive of surface alteration (weathering) and metamorphism. These changes happen at relatively low temperatures and pressures and result in changes to the rock's original mineralogy and texture. There is no sharp boundary between diagenesis and metamorphism, but the latter occurs at higher temperature and pressure than the former.
(limestone) fossiliferous
Biochemical rock, Formed by the accumulation and consolidation of macroscopic calcite fossils, made of calcite, Medium to coarse-grained, warm, shallow, marine environment, White/gray/pink
diatomite
Biochemical rock, white, no Hcl reaction, similar to chalk
chert
Chemical Rock, Made of quartz, microscopic grain, lighter than flint, formed from silica
dolostone
Chemical rock, medium/fine grains, form in marine environments
(Limestone) Travertine
Chemical sedimentary rock, Generally banded, Usually very fine grained, Formed in caves, calcite carbonate composition, light colored
(limestone) oolitic
Chemical, made of little round pieces called ________, medium grain size, usually light colored.
Coquina
Chemical/Biochemical Rock, visible shells, fragments loosely cemented, made of CALCITE
chert
Chert is a microcrystalline or cryptocrystalline sedimentary rock material composed of silicon dioxide (SiO2). It occurs as nodules, concretionary masses and as layered deposits. breaks with a conchoidal fracture, often producing very sharp edges. Early people took advantage of how it breaks and used it to fashion cutting tools and weapons. Dark varieties are common and are often called "flint".
conglomerate
Clastic Rock, Very coarse grains, rounded pieces of rock, formed in rivers, beaches..
Breccia
Clastic, coarse sized grains, usually near-surface faults, angular clasts
sandstone
Clastic, super fine/medium quartz grained, similar sized grains, very common.
shale
Clastic, very fine, silt and clay (mud) grain size, common in low energy environments such as lakes, deep ocean, flood plains, and deltas, hardens into slate
(Limestone) chalk
Formed by the accumulation of microscopic marine calcite fossils, Biochemical sedimentary rock, Very fine grained, calcite composition, marine environment.
conglomerate
In breccia the large particles are angular in shape but in ______ the particles are rounded. This reveals a difference in how far the particles were transported. Near the outcrop where the fragments were produced by mechanical weathering the shape is angular. However, during transport by water away from the outcrop the sharp points and edges of those angular fragments are rounded.
(limestone) travertine
In the U.S., the most well-known place for formation is Yellowstone National Park, where the geothermal areas are rich in these limestone deposits. Oklahoma has two parks are dedicated to this natural wonder. is often used as a building material. The Romans mined deposits of it for building temples, aqueducts, monuments, bath complexes, and amphitheaters such as the Colosseum, the largest building in the world constructed mostly of this.
lignite coal
Lowest rank of coal, brownish black, visible plant material, crumbly, organic rock, higher than peat.
bituminous coal
Middle-hardest coal, formed from lignite coal, medium/fine grain, alternating dull and shiny layers. Chemical/Biochemical Rock
(limestone) fossiliferous
Most form in shallow, calm, warm marine waters. That type of environment is where organisms capable of forming calcium carbonate shells and skeletons can easily extract the needed ingredients from ocean water. When these animals die their shell and skeletal debris accumulate as a sediment that might be lithified into this
arkose
Quartz is commonly the dominant mineral component, and some mica is often present. usually contains small amounts of calcite cement, which causes it to 'fizz' slightly in dilute hydrochloric acid; sometimes the cement also contains iron oxide. typically grey to reddish in colour. The sand grains may range from fine to very coarse, but tends toward the coarser.
sandstone
Rock formations that are primarily composed of _______ usually allow percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Fine-grained aquifers are more apt to filter out pollutants from the surface than are rocks with cracks and crevices
arkose
Very coarse sandstone, mostly quartz and feldspar, usually cemented with calcite, usually pink or gray. Clastic Rock
diatomite
a chalk-like, soft, friable (crumbly), earthy, very fine-grained, siliceous sedimentary rock, usually light in color. It is very finely porous, very low in density (floating on water at least until saturated), and essentially chemically inert in most liquids and gases. now used principally as a filter aid; also absorbent for industrial spills, pet litter, a filler in products from paints to dry chemicals, insulation material, sawn and molded shapes, a mild abrasive in polishes, and a silica additive in cement
sandstone
a clastic sedimentary rock composed mainly of sand-sized minerals or rock grains. mostly composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. may be any color, but the most common are tan, brown, yellow, red, gray, pink, white and black.
lignite
a dark brown to black combustible mineral formed over millions of years by the partial decomposition of plant material subject to increased pressure and temperature in an airless atmosphere.
arkose
a detrital sedimentary rock, specifically a type of sandstone containing at least 25% feldspar.
chert
a fine-grained silica-rich microcrystalline, cryptocrystalline or microfibrous sedimentary rock that may contain small fossils. It varies greatly in color (from white to black), but most often manifests as gray, brown, grayish brown and light green to rusty red; its color is an expression of trace elements present in the rock, and both red and green are most often related to traces of iron (in its oxidized and reduced forms respectively).
shale
a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite. Fossils, animal tracks/burrows and even raindrop impact craters are sometimes preserved on the bedding surfaces.
(limestone) fossiliferous
a form of limestone that is often white, pink, red, buff, gray or black and has many plant or animal fossils in the matrix of the rock. Like other limestone, it is composed of calcite and will dissolve in acid
diatomite
a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder. It has a particle size ranging from less than 1 micrometre to more than 1 millimetre, but typically 10 to 200 micrometres.[1] This powder has an abrasive feel, similar to pumice powder, and is very light, due to its high porosity. consists of fossilized remains of diatoms, a type of hard-shelled algae.
dolostone
a sedimentary carbonate rock that contains a high percentage of the mineral with the same name, 50% or greater content of magnesium replacing calcium, often as a result of diagenesis
(Limestone) Crystalline
a sedimentary rock consisting of more than 50% calcium carbonate (calcite - CaCO3), chemical rock, fine-coarse grained,
coquina
a sedimentary rock that is composed of the transported, abraded, and mechanically sorted fragments of the shells of either molluscs, trilobites, brachiopods, or other invertebrates. average size of the particles composing it should be 2 mm or greater in size. can vary in hardness from poorly to moderately-cemented. derived from the Spanish word for cockleshells or shellfish.
(limestone) chalk
a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms
breccia
a type of clastic sedimentary rock which are composed of angular to subangular, randomly oriented clasts of other sedimentary rocks. They are formed by either submarine debris flows, avalanches, mud flow or mass flow in an aqueous medium
(limestone) chalk
composed mostly of calcium carbonate with minor amounts of silt and clay. It is normally formed underwater, commonly on the sea bed, then consolidated and compressed during diagenesis into the form commonly seen today. During diagenesis silica accumulates to form chert or flint nodules within the carbonate rock.
(limestone) travertine
form of limestone deposited by mineral springs, especially hot springs. often has a fibrous or concentric appearance and exists in white, tan, and cream-colored varieties. It is formed by a process of rapid precipitation of calcium carbonate, often at the mouth of a hot spring or in a limestone cave. can form stalactites, stalagmites. frequently used in Italy and elsewhere as a building material. a terrestrial sedimentary rock, formed by the precipitation of carbonate minerals from solution in ground and surface waters, and/or geothermally heated hot-springs
conglomerate
forms in a very energetic environment, where rocks are eroded and carried downhill so swiftly that they aren't fully broken down into sand. Another name for - puddingstone. A rock consisting of individual clasts within a finer-grained matrix that have become cemented together. they are sedimentary rocks consisting of rounded fragments.
coquina
forms near shore, where wave action is vigorous and sorts the sediments well. Most limestones have some fossils in them, and many have beds of shell hash, but this is the extreme version
anthracite coal
hardest coal. (Actually a metamorphic rock?) Forms from bituminous coal. Has the highest energy content of all coals. Chemical/Biochemical Rock
anthracite
hardest type of coal with the highest carbon content. As it has few impurities, it burns with a clean flame, and so is the preferred coal for use as a fuel. more of ametamorphic rock, it is formed when sedimentary coal (mined as bituminous coal) is subjected to high temperatures and pressures within the Earth's crust.
breccia
is a rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix
shale
typically composed of variable amounts of clay minerals and quartz grains and the typical color is gray. Addition of variable amounts of minor constituents alters the color of the rock. Black results from the presence of greater than one percent carbonaceous material and indicates a reducing environment. Red, brown and green colors are indicative of ferric oxide (hematite - reds), iron hydroxide (goethite - browns and limonite - yellow), or micaceous minerals (chlorite, biotite and illite - greens).
dolostone
usually a former limestone in which the mineral calcite is altered looks like limestone, but does not bubble when treated with weak acid. mostly light gray in color. crystals are usually small- to medium-sized, and freshly broken surfaces may glitter in sunlight.
