Chalk depositional environment

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Chalk depositional environment. Stylolites, porosity, depositional texture, and silicates in chalk facies sediments. Ontong Java Plateau - Gorm and Tyra fields, North Sea. Sedimentology (2007) I.L. Fabricius et al. ... which were deposited in the similar sedimentary environment with shale core samples in the same layer, are always used to indicate reservoir ...

Limestones may be divided on the basis of their depositional environments into three categories: 1) platform, 2) basin, 3) geosynclinal. Platform limestones are thin, widespread, light colored, fossiliferous limestones which are often dolomitized. Basin limestones of the open basin type are lithologically similar to platform limestones, but ...

Modified date: 23/04/2023. Chert. Chert is a fine-grained sedimentary rock composed of quartz (SiO2) that is microcrystalline or cryptocrystalline quartz. It is usually organic rock but also occur inorganically as a chemical precipitate or a diagenetic replacement. It occurs as nodules, concretionary masses, and as layered deposits.This stratification results from the deposition of sediments in distinct layers or beds, with variations in clast size, sorting, or composition between layers. High Energy Environments: Conglomerate is typically associated with high-energy environments, such as riverbeds, alluvial fans, coastal areas, or glacial deposits. These environments ...The Toolebuc Formation is a condensed section formed during a relative rise in sea level. The depositional environment was a shallow sea (50-200 m deep) with a lush growth of planktic algae in the photic zone. The Toolebuc accumulated below wave base and below the photic zone, in anoxic bottom waters.2 thg 11, 2020 ... ... depositional environment in the early Jurassic. The North Sea Basin ... Chalk deposition culminated in the Late Cretaceous, where the influx ...Introduction. The deep ocean is the world’s largest depositional environment, encompassing all of the ocean floor below the continental shelf and slope environments. The majority of deposition away from continental margins takes place where there is little to no flow to transport sediments in from elsewhere.Depositional environment. A diagram of various depositional environments. In geology, depositional environment or sedimentary environment describes the combination of physical, chemical, and …

Stratigraphy and depositional environment of Smoky Hill Chalk Member, Niobrara Chalk (Upper Cretaceous) of the type area, western Kansas. Lawrence, Kan. : Kansas Geological Survey, University of Kansas ; Distributed from Lawrence, University of …Geologists use _____ rocks to determine past environments of deposition on Earth's surface. These types of rocks preserve a variety of characteristics that might suggest temperature, elevation, geographic location, and changes in climate. sedimentary. Match the environmental depositional shift to its correct description.Limestone is a sedimentary rock composed primarily of calcite, a calcium carbonate mineral with a chemical composition of CaCO 3. It usually forms in clear, calm, warm, shallow marine waters. Limestone is usually a biological sedimentary rock, forming from the accumulation of shell, coral, algal, fecal, and other organic debris.Facies analysis and environmental reconstruction of the Upper Cretaceous Chalk ... An interpretation of the depositional environment is then created per unit.Chalk. Chalk, a sedimentary rock, is a soft form of limestone that is not well cemented and thus is often powdery and brittle. It usually ranges in color from white to light gray to buff and forms from sediment deposited in a saltwater environment. Composed mostly of the mineral calcite and formed mainly from the remains of floating ... The sediment preservation potential is very high in these environments because deposition often occurs on the continental shelf and underwater. Shoreline environments are an important source of hydrocarbon deposits (petroleum, natural gas). The study of shoreline depositional environments is called sequence stratigraphy. Sequence stratigraphy ...They are a product of deposition from a slowing current (Figure 6.4.4 6.4. 4 ). Most graded beds form in a submarine-fan environment (see Figure 6.4.1 6.4. 1 ), where sediment-rich flows descend periodically from a shallow marine shelf down a slope and onto the deeper sea floor. Some graded beds are reversed (coarser at the top), and this ...

Depositional environment Schematic E-W section showing the Eagle Ford Shale among the geological strata beneath the DFW Metroplex. The Eagle Ford was deposited in an inland sea (or epeiric sea) that covered much of modern-day Texas.The Texas shelf during the Cenomanian-Turonian was bounded by the Ouachita Uplift to the north, the Sabine …Rock Name: Chalk Depositional Environment: Chalk is usually formed in the ocean and is composed of marine shells. 4 ESS 7, Laboratory 5, Fall 2020 Name: ___Magaly Bravo ____ Part B: Rates of sediment deposition (10 pts) You encounter the sedimentary rock outcrop shown above while you are out hiking.Introduction. The deep ocean is the world’s largest depositional environment, encompassing all of the ocean floor below the continental shelf and slope environments. The majority of deposition away from continental margins takes place where there is little to no flow to transport sediments in from elsewhere.What are the symptoms of oil deposits? Check out 5 symptoms of oil deposits at HowStuffWorks. Advertisement If your arteries ever became clogged with gunk -- as does happen from time-to-time with us humans -- you and your doctor would want ...Study with Quizlet and memorize flashcards containing terms like _____ is a form of calcium carbonate. Correct! Travertine Chert Lignite Gypsum, graywacke is _____. Correct! a sandstone with the sand grains embedded in a clay-rich matrix a limestone with abundant, sand-sized, quartz grains a dark, organic-rich, chemical sedimentary rock containing …

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Depositional Environments A sedimentary environment is a geographic location characterized by a particular combination of geologic processes and environmental conditions. Geologic processes include the currents that transport and deposit sediments (water, wind, or ice) and the plate tectonic settings that affect sedimentation. Limestone (calcium carbonate CaCO 3) is a type of carbonate sedimentary rock which is the main source of the material lime.It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of CaCO 3.Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place …10 feet below the Austin Chalk – Upper Boquillas/Eagle Ford contact (Fébourg et al., 2016). The Cenomanian and Turonian Stages were characterized by deposition during very low oceanic circulation, likely due to the non-glacial warm climate of the Cretaceous Period (Linnert et al., 2011).transition from upper Eagle Ford to Austin Chalk lithologies. The Langtry member is a 40-90 ft thick depositional sequence that records a subtle upward gradation from the underlying Eagle Ford to the overlying Austin Chalk (Donovan and Staerker, 2010). The correlations by Rock Name: Chalk Depositional Environment: Chalk is usually formed in the ocean and is composed of marine shells. 4. ESS 7, Laboratory 5, Fall 2020 Name: ___Magaly Bravo ____ Part B: Rates of sediment deposition (10 pts) You encounter the sedimentary rock outcrop shown above while you are out hiking.

In these depositional environments, the rock unit may develop sedimentary ... Is chalk a sedimentary rock? Yes. It is made up of all those tiny dead sea ...This stratification results from the deposition of sediments in distinct layers or beds, with variations in clast size, sorting, or composition between layers. High Energy Environments: Conglomerate is typically associated with high-energy environments, such as riverbeds, alluvial fans, coastal areas, or glacial deposits. These environments ...(ii) The lithological variation of the chalk of Hallue Catchment in relation to depositional setting. (iii) Site specific data that might be required for the ...Conglomerate rocks provide valuable information to geologists about the geological history and environmental conditions of the past. They can contain clues about the type and origin of the clasts, the energy of the depositional environment, and the age of the rock layer in which they are found. Conglomerate LocalitiesHard, white and gray sandy chalk. DEPOSITIONAL ENVIRONMENT Shallow marine to deeper shelf. RESERVOIR CONSIDERATIONS Depth to top of pay: 2000’ – 2500’ Net pay: 10’ – 70’ Porosity (´): 5 – 25 % Permeability (k): as high as 500 md Drive Mechanism: Water drive, gas cap Hydrocarbon: Gas PERTINENT PUBLICATIONSDepositional Environments A sedimentary environment is a geographic location characterized by a particular combination of geologic processes and environmental conditions. Geologic processes include the currents that transport and deposit sediments (water, wind, or ice) and the plate tectonic settings that affect sedimentation.1. Introduction. Upper Cretaceous chalk mainly formed by the settling and accumulation of small debris of calcareous nannofossils (coccolithophorids), planktonic foraminifera and calcispheres (Scholle, 1977; Robaszynski et al., 1982).Its depositional environment often is interpreted as calm with low hydrodynamic conditions below or …Micrite, sedimentary rock formed of calcareous particles ranging in diameter from 0.06 to 2 mm (0.002 to 0.08 inch) that have been deposited mechanically rather than from solution. The particles, which consist of fossil materials, pebbles and granules of carbonate rock, and oölites (sphericalThe Grey Chalk is coloured by its clay content and reflects the lower sea-levels, and hence greater extent of land from which clays were sourced, at the beginning of chalk deposition. Much of the Grey Chalk is comprised of alternating marly-chalk and clay-poor chalk. The remainder of the Chalk, the White Chalk, was deposited whilst sea-levels ...Chalk. Chalk, a sedimentary rock, is a soft form of limestone that is not well cemented and thus is often powdery and brittle. It usually ranges in color from white to light gray to buff and forms from sediment deposited in a saltwater environment. Composed mostly of the mineral calcite and formed mainly from the remains of floating ...

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At the basin scale, the Upper Maastrichtian chalk is dominated by stable pelagic depositional conditions and a subtle change is observed towards the top of M1 unit. The gamma ray log response and mineralogical analysis show an increase in IR content and thus, a shift towards hemipelagic depositional conditions ( Table 1 ; Fig. 2 ).Sedimentary rock - Clastic, Chemical, Organic: There are many different systems of classifying sandstones, but the most commonly used schemes incorporate both texture (the presence and amount of either interstitial matrix—i.e., clasts with diameters finer than 0.03 millimetre—or chemical cement) and mineralogy (the relative amount of quartz and the …Geologists use _____ rocks to determine past environments of deposition on Earth's surface. These types of rocks preserve a variety of characteristics that might suggest temperature, elevation, geographic location, and changes in climate. sedimentary. Match the environmental depositional shift to its correct description.Study with Quizlet and memorize flashcards containing terms like _____ is a form of calcium carbonate. Correct! Travertine Chert Lignite Gypsum, graywacke is _____. Correct! a sandstone with the sand grains embedded in a clay-rich matrix a limestone with abundant, sand-sized, quartz grains a dark, organic-rich, chemical sedimentary rock containing …It has been attempted to map these allochthonous units as well as their source areas in order to gain a better understanding of the depositional environments during Chalk deposition in the Central Graben. Keywords. Debris Flow; Trace Fossil; Siliceous Sponge; Central Trough; Chalk Group; These keywords were added by machine and not by the authors.Chert is a fine-grained sedimentary rock composed of quartz (SiO2) that is microcrystalline or cryptocrystalline quartz. It is usually organic rock but also occur inorganically as a chemical precipitate or a diagenetic replacement. It occurs as nodules, concretionary masses, and as layered deposits. Name origin: Term is used to refer generally ...Deeper-water chalk deposition was the general background environmental setting, but it was disrupted by this period of volcanism that initiated numerous mass-wasting complexes punctuating the deeper-water chalk deposits. Within the gravity-flow deposits, volcanic components such as lapilli, ash, and glauconite-altered volcanic grains occurred ...

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Characteristically, the Paluxy Formation is a reddish sandstone and shale unit that supports Post Oaks. The environments of deposition were coastal streams and beach environments. Ancient beach deposits form localized dunes of white, well rounded, friable sand. Some iron stains are present in these dunes. At the basin scale, the Upper Maastrichtian chalk is dominated by stable pelagic depositional conditions and a subtle change is observed towards the top of M1 unit. The gamma ray log response and mineralogical analysis show an increase in IR content and thus, a shift towards hemipelagic depositional conditions ( Table 1 ; Fig. 2 ).Some of the more important of these environments are illustrated in Figure 6.3.1. Figure 6.3.1 Some of the important depositional environments for sediments and sedimentary rocks. Table 6.4 provides a summary of the processes and sediment types that pertain to the various depositional environments illustrated in Figure 6.3.1.Aug 22, 2023 · Three depositional sedimentary environments are recognized, namely, continental, transitional or marginal and marine. Each depositional environment has various subdivisions. Shales are generally deposited in lacustrine (continental), deltaic (transitional) and marine depositional environments and may correspondingly be classified as such; that ... In addition there are 15 species of bivalves. These deposits resulted from quiet conditions of deposition. They are thought to have been deposited in shallow inner-shelf mudstone environments. Finely laminated mudstone. Grey featureless mudstone with some thin impersistent siltstone beds only 1–5 cm thick. This facies occurs mainly in the north.Nov 10, 2015 · Geologists refer to the conditions in which sediment was deposited as the depositional environment. Examples include beach, glacial, and river environments. To identify depositional environments, geologists, like crime scene investigators, look for clues. Detectives may seek fingerprints and bloodstains to identify a culprit. Deeper-water chalk deposition was the general background environmental setting, but it was disrupted by this period of volcanism that initiated numerous mass-wasting complexes punctuating the deeper-water chalk deposits. Within the gravity-flow deposits, volcanic components such as lapilli, ash, and glauconite-altered volcanic grains occurred ...Depositional Environment Regional Setting and Stratigraphic Framework of Smoky Hill Deposition. The Smoky Hill Member of Kansas was deposited in the eastern part of a broad seaway, which in Late Cretaceous time extended from the Gulf of Mexico to Arctic Canada. The subsiding trough containing these waters has been called the Rocky Mountain ...A coastal depositional environment where a river meets an ocean or other large body of water, complex, and result in a variety of sediments and sedimentary rocks. What are the two types of marine depositional environments? Rock salt is the name of a sedimentary rock that consists almost entirely of halite, a mineral composed of sodium chloride, NaCl. It forms where large volumes of sea water or salty lake water evaporate from an arid-climate basin -- where there is a replenishing flow of salt water and a restricted input of other water.a single layer of sediment or sedimentary rock with a recognizable top and bottom. bedding. layering or stratification in sedimentary rocks. biochemical sedimentary rock. sedimentary rock formed from material (such as shells) produced by living organisms. biochemical limestone. organisms make solid shells out of calcium carbonate, either as ... ….

Delta. A delta is a low-lying, almost flat landform, composed of sediments deposited where a river flows into a lake or an ocean.Deltas form when the volume of sediment deposited at a river mouth is greater than what waves, currents, and tides can erode. Deltas extend the coastline outward, forming new land along the shore. However, …Chert. Chert is a hard and compact sedimentary rock, consisting dominantly of very small quartz crystals. It is a common rock type which occurs mostly in carbonate rocks either in nodular form or in layers (bedded chert). Flint on the coast at Stevns Klint in Denmark. Gray rocks in the background are also flint boulders, but they lack fresh ... Chalk is calcium carbonate and has the same chemical composition as limestone, marble, ground calcium carbonate and precipitated calcium carbonate. Chalk, like the other types of calcium carbonate, is in the form of calcite, which is a crys...Sedimentary structures. Sedimentary structures are the larger, generally three-dimensional physical features of sedimentary rocks; they are best seen in outcrop or in large hand specimens rather than through a microscope.Sedimentary structures include features like bedding, ripple marks, fossil tracks and trails, and mud cracks. They …Chalk. Chalk, a sedimentary rock, is a soft form of limestone that is not well cemented and thus is often powdery and brittle. It usually ranges in color from white to light gray to buff and forms from sediment deposited in a saltwater environment. Composed mostly of the mineral calcite and formed mainly from the remains of floating ... Oct 12, 2007 · The study shows that seismic scale depositional features in the Danish Basin and Central Graben of the Chalk Sea can be explained by sediment enhanced dense water cascading. A reflection of the depositional environment. Lithofacies - defined by lithologic features ; Biofacies - defined by organic features; Sedimentary Facies. Facies occur laterally adjacent to one another just as do their depositional environments. Two different facies can have similar lithofacies but different biofacies, or vice-versa. ...Nov 1, 2014 · Thickness maps of each depositional sequence illustrate the tectonic evolution of the San Marcos Arch and its influence on the deposition of the Austin Chalk Group, which is judged as negligible during most of the lower Austin Chalk Group (Coniacian), and started to trigger lateral thickness variations and pinch-outs in the Santonian and early ... Match the following Chemical Sedimentary Rocks with the depositional environment that they formed in. chert [ Choose ] travertine [Choose ] chalk [Choose ] coal [ Choose ] evaporites [Choose] oolitic limestone [Choose ] organic limestone [Choose ] coquina [ Choose ] [Choose ] hot springs, from evaporation of calcium carbonate-supersaturated hot water. deep marine environments due to the ...Figure 7.5.13 7.5. 13: The light blue reef is fringing the island of Vanatinai. As the island erodes away, only the reef will remain, forming a reef-bound seamount. Sediment found in coral reefs is typically fine-grained, mostly carbonate, and tends to deposit between the intact coral skeletons. Chalk depositional environment, sandstone. rounded to subangular. well to moderately. quartz arenite - >90% quartz. subrounded to angular. well to moderately. arkose - >25% feldspar. subangular to angular. moderately to poorly., May 1, 2021 · The Upper Cretaceous to Lower Paleocene Chalk Group represents an important reservoir target for hydrocarbon and energy storage in the UK, Norwegian and Danish sectors. Chalk is a microporous rock mainly composed of μm-sized fragments of disaggregated coccolithophorids tests and characterised by low permeability below 10 mD. , A sedimentary structure reflects the depositional environment under which the rock was deposited. Bedding - sediments are arranged into layers defined by bedding planes; usually horizontal, but may also be subhorizontal or curved. Graded bedding - bedding in which the particles are sorted according to density, size, and shape. Normal grading ..., Facies analysis and environmental reconstruction of the Upper Cretaceous Chalk ... An interpretation of the depositional environment is then created per unit., Chalk is a type of limestone formed by microscopic algal plates, ... Lakes are great depositional environments, as stuff flows into the lakes but generally not out of them. Since lakes are generally slower moving than rivers (duh!!) they do not carry sand; it is silt and clay (i.e., mud) which is the main sediment types. ..., Type Sedimentary Rock Origin Chemical-Biochemical Texture Nonclastic; Very Fine-grained Composition Calcite Color Black Miscellaneous Microcrystalline; Reacts with HCl; Hardness < Glass Depositional Environment Variable Depth Continental Shelf/Platform Marine, The tectonic setting is characterized by ... It seems likely, therefore, that changes in these variables, resulting from differences in original depositional ..., transition from upper Eagle Ford to Austin Chalk lithologies. The Langtry member is a 40-90 ft thick depositional sequence that records a subtle upward gradation from the underlying Eagle Ford to the overlying Austin Chalk (Donovan and Staerker, 2010). The correlations by, Carbonate depositional settings. (A) Marine environment with a marginal reef separating the forereef from a lagoon; oblique aerial view of a reef system on the coast of Caicos Island. (B) Hot-spring environment with carbonate (travertine) deposits formed of dendritic calcite crystals; spring KL6 at Loburu, Lake Bogoria, in the Kenyan Rift Valley., Niobrara Chalk was weathered and opalized in the Valentine phase of the Ogallala Formation. The Niobrara Formation / ˌnaɪ.əˈbrærə /, also called the Niobrara Chalk, is a geologic formation in North America that was deposited between 87 and 82 million years ago during the Coniacian, Santonian, and Campanian stages of the Late Cretaceous. , Chalk. Chalk, a sedimentary rock, is a soft form of limestone that is not well cemented and thus is often powdery and brittle. It usually ranges in color from white to light gray to buff and forms from sediment deposited in a saltwater environment. Composed mostly of the mineral calcite and formed mainly from the remains of floating ..., The Toolebuc Formation is a condensed section formed during a relative rise in sea level. The depositional environment was a shallow sea (50-200 m deep) with a lush growth of planktic algae in the photic zone. The Toolebuc accumulated below wave base and below the photic zone, in anoxic bottom waters. , When you can automate daily activities, it’s almost always a win. Direct deposits are an easy way to send or receive a payment. Sometimes you can opt in for this payment method, and other times there may be no other alternative than to arra..., nodular chalk deposition, above Glynde Marl 1 (Mortimore 1986; Mortimore et al. ... Cretaceous) hot greenhouse climate. Science China Earth Sciences, doi ..., Specific objectives are to (1) define the. Austin Chalk depositional setting and environments in the. Sabine Arch; (2) describe the range of lithofacies ..., Chemical properties and the diagenetic history of chalk are assumed to be strongly dependent on primary composition, texture, and depositional setting., Chalk. A chalk is a soft, friable variety of limestone consisting of poorly lithified calcareous ooze, produced by the accumulation of planktonic organisms in a pelagic (open sea) environment. Chalk is largely made of shells of single-celled marine organisms, such as foraminifera and coccoliths, but fragments of shells of bivalves and ostracods ..., Depositional environment for the rocks of the DFW Metroplex. The DFW Metroplex sprawls across a 100 kilometers ... Austin chalk is the well known white rock that the city of Dallas sits on. Volcanic ashes are present in the Austin chalk, and were deposited by wind from distant erupting volcanoes and erupting igneous intrusions around 86 Ma., What are the symptoms of oil deposits? Check out 5 symptoms of oil deposits at HowStuffWorks. Advertisement If your arteries ever became clogged with gunk -- as does happen from time-to-time with us humans -- you and your doctor would want ..., Submarine diagenesis. Micrite envelopes document a period of alteration concurrent with deposition. The micritized surfaces of grains commonly survive dissolution and provide a surface for later precipitation of cements. In Isla de Mona, micrite envelopes are common in all sections and environments, although they are more prevalent in the ... , People use safe deposit boxes to hold a variety of important papers and other items. Because the uses are so varied they come in a variety of different sizes. Most financial institutions offer them for rent or as a perk to their customers., Tidal Flats. Figure 6.5.10 6.5. 10: General diagram of a tidal flat and associated features. Tidal flats, or mudflats, are sedimentary environments that are regularly flooded and drained by ocean tides. Tidal flats have large areas of fine-grained sediment but may also contain coarser sands., Mar 1, 2020 · Thickness maps of each depositional sequence illustrate the tectonic evolution of the San Marcos Arch and its influence on the deposition of the Austin Chalk Group, which is judged as negligible ... , Rock chalk contains many tiny algae shells and shrimp feces. This is evidence of which depositional environment? discomformities. Which of the following would NOT be considered evidence for an orogeny? About us. About Quizlet; How Quizlet works; Careers; Advertise with us; Get the app;, Depositional environments. Sedimentary rocks are formed by 5 processes, there are erosion, weathering, transport, deposition, and diagenesis process (Boggs, 1991). These 5 processes with 4 types of rocks make up a cycle that is known as sedimentary cycle. The properties of sedimentary rocks such as sediment textures and structures, are formed ..., Erosion was terminated by the deposition of the lower Taylor Marl. Taylor A, the lowermost subdivision of the lower Taylor, was deposited in a near-shore environment that was highly variable. Of particular interest is the relationship of this unconformity to structure and probably to oil occurrence in the Austin Chalk in McLennan and Falls ..., Figure 7: Generalized depositional episode for the Austin Chalk. Thick accumulations of open-shelf carbonates dominate this time period, with deposition being largely effected by the active San Marcos Platform (adapted from Galloway, 2008)..... 17 Figure 8: Generalized depositional episode of the Navarro., After deposition, the chalk sediments were partly redistributed by bottom currents, which locally changed the sea floor morphology, resulting in the development of valleys, ridges, channels, moats, scours and drifts, indicating that the ‘chalk sea’ was a highly dynamic depositional environment (Surlyk et al. 2003, 2008; Lykke-Andersen and ..., Karachi, city and capital of Sindh province, southern Pakistan.It is the country's largest city and principal seaport and is a major commercial and industrial centre. Karachi is located on the coast of the Arabian Sea immediately northwest of the Indus River delta.. The city has been variously called Caranjee, Crochey, Krotchey, Currachee, and Kurrachee, all of which are believed to be ..., Erosion was terminated by the deposition of the lower Taylor Marl. Taylor A, the lowermost subdivision of the lower Taylor, was deposited in a near-shore environment that was highly variable. Of particular interest is the relationship of this unconformity to structure and probably to oil occurrence in the Austin Chalk in McLennan and Falls ..., Hard, white and gray sandy chalk. DEPOSITIONAL ENVIRONMENT Shallow marine to deeper shelf. RESERVOIR CONSIDERATIONS Depth to top of pay: 2000’ – 2500’ Net pay: 10’ – 70’ Porosity (´): 5 – 25 % Permeability (k): as high as 500 md Drive Mechanism: Water drive, gas cap Hydrocarbon: Gas PERTINENT PUBLICATIONS, The chalk world began to come into existence around 80-100 million years ago, when the Earth was entering a warming phase. Seas rose rapidly, and one third of the landmasses present today ..., This encompasses about one-third of the modern ocean system. Rates of coccolith ooze accumulation vary from about 1 to 10 m/Myr in the oligotrophic open ocean; however, accumulation rates in the marginal “chalk” seas of the Late Cretaceous, during the height of chalk deposition, were as high as 100 m/Myr.