Grain size of siltstone

6.1 Clastic Sedimentary Rocks. A is a fragment of rock or mineral, ranging in size from less than a micron [1] (too small to see) to as big as an apartment block. Various types of clasts are shown in Figure 5.3.1 and in Exercise 5.3. The smaller ones tend to be composed of a single mineral crystal, and the larger ones are typically composed of ...

Grain size of siltstone. Grain Size < 1/256 mm. Crystalline, Clastic, or Amorphous: Composition ... indurated mud; includes claystone and siltstone Shale: finely fissile; may include much silt

Choose one: A. A well-sorted clastic rock is made up of different-sized particles. B. Conglomerates consist of a single grain size. C. An immature clastic rock has well-sorted, resistant grains. D. Pieces of broken rock produced by physical weathering are collectively called clasts or detritus. D. Pieces of broken rock produced by physical ...

The majority of sandstone and siltstone pores were larger than 1000 nm in diameter. The sandstone had a minimum pore size of 3000 nm, while the siltstone had a minimum pore size of around 15 nm. The coal pore size was found to be linear between 10,000 nm and 3 nm, according to the MIP test in which the maximum pressure of 400 …Question: 2. Arrange the following sedimentary rocks in descending order according to their grain size: a. Conglomerate b. Mudstone c. Breccia Graywake g. coquina d. Shale e. f. Siltstone h.Banded sandstone i. Red sand stone i. Sandstone with calcite cement k. Arkose. Medium to dark gray, laminated shale and siltstone; weathers to light olive-gray; grain size coarsens upward; thickness about 2,000 feet in west, about 1,7000 feet in east; and Harrell Shale - Dark gray laminated shale; absent in east where Brallier lies directly on Mahantango, Tully Limestone lies near base in west, in subsurface of Garrett ...raphy. Confusion of grain size and min-eral composition is especially pro-nounced in the usage of the term "gray-wacke," which has been applied indis-criminately to all clayey sandstones (a textural category), regardless of the min-eral composition of the sand portion. In addition to mineral composition and grain size, there is a third importantThe detrital grain size of siltstone reservoirs occupies a middle ground between sandstones and shales, both of which are better understood in terms of their petrophysical properties. Because ...1 ene 2020 ... Siltstone.Silt-sized grains are by definition between 1/16 and 1/256 mm. This sample from the Spray River Group of Western Canada is quarried ...depending on the grain size of the sediment, there may be doubt as to whether a material is actually predominantly a mudstone/shale or a siltstone. This can only be resolved by sampling and grain size analysis. Should any conflict arise it is recommended that the division at 63 µm be used as this is widely recognised.

Wild rice isn’t actually rice, but it is Minnesota’s state grain. People have been eating it for thousands of years in the region, and it’s an important cultural food. Every year as the summer fades into fall, Minnesota embraces wild rice. ...Specific ranges of grain size have specific names. Gravel is an overall name for large sediment grain size, which includes boulder, cobble, and pebble. Sand includes sediment grains ranging in size from 2mm to 0.625 mm. Silt is the name of a sediment grain that range in size from 0.625 mm to 0.0039 mm. Mud is the smallest grain size and is also ...4. Siltstone - cemented, silt-sized particles. 5. Claystone - cemented clay-sized particles. *If the rock is composed of two or more grain sizes, the name is based on the most abundant size. 6. Shale - fine-grained rock composed of silt and clay which tends to part along the bedding planes. It is the most abundant sedimentary rock.Get ratings and reviews for the top 7 home warranty companies in Grain Valley, MO. Helping you find the best home warranty companies for the job. Expert Advice On Improving Your Home All Projects Featured Content Media Find a Pro About Writ...B. If grains or crystals are not visible, or barely visible with a hand lens: 1. The rock is a shale or mudstone . 2. It is a chemical or biochemical rock . If Table 4.4 is chosen, determine the grain size and mineral composition. These terms refer to grain size: Claystone Mudstone Siltstone Shale Sandstone ConglomerateSilt is any particle smaller than sand, 1/16 of a millimeter, and larger than clay, 1/256 of millimeter. Silt is believed to be the product of physical weathering, which can involve freezing and thawing, thermal expansion, and release of pressure.

Earth Sciences. Earth Sciences questions and answers. Instructions for Filling in the Sedimentary Rock Identification Table Column 1: Grain Size (If Visible) There are three ways to measure grain size: r Measure the size of the grains in millimeters with a ruler. This works well for gravel-sized clasts, but it may be difficult for finer-grained ...Type Sedimentary Rock Origin Detrital/Clastic Texture Clastic; Fine-grained (0.004 – 0.06 mm) Composition Quartz, clay minerals Color Reddish brown Miscellaneous Massive; Feels slightly gritty Depositional Environment Flood plain, Delta, or Mid-continental ShelfFeb 15, 2016 · The porosity and dominant pore radii of granular porous media such as sandstones and mudstones are partially controlled by grain size. At a given porosity, the dominant pore throat radii, and thus permeability, commonly increase with increasing grain size [1], [2], [3]. Download scientific diagram | (A) Comparison of representative grain size distributions between the eolian siltstone and fine-grained sandstone (solid lines) and the underlying fluvial sandstone ...D=laminated siltstone grading to mudstone. Graded bedding refers to a sequence of increasingly coarse- or fine-grained sediment layers. Graded bedding often develops when sediment deposition occurs in an environment of decreasing energy. ... Grain size, flow velocity, and flow regime or pattern interact to produce bedforms having unique ...

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... grains and is often tan to white in color. The fine-grained rock forms from silt-sized feldspar and quartz. Silt is between the sizes of clay and sand.What is the grain size of siltstone? between 0.004 and 0.063 mm Silt is loose pelite sediment and siltstone is pelite rocks, containing >66% silt grain size particle size ranging between 0.004 and 0.063 mm.Siltstone Organic petrology 1. Introduction The porosity and dominant pore radii of granular porous media such as sandstones and mudstones are partially …The sequence of increasing grades of metamorphism of a mudstone (shale, claystone, or siltstone) parent rock (protolith) is slate (lowest grade), phyllite, schist, gneiss (highest grade) Slate x1 Phyllite x1 Schist x1 1. Describe the change in grain size from slate to schist. 2. How does the texture of phyllite differ from that of schist? 3.Texture: Clastic; Fine-grained (0.004 – 0.06 mm) Composition: Quartz, clay minerals Color: Reddish brown Miscellaneous: Massive; Feels slightly gritty Depositional Environment: Flood plain, Delta, or Mid-continental Shelf Grain size: Fine- grained Siltstone Composition Clastic sedimentary rocks are deposited in three ways.Apr 23, 2023 · Modified date: 23/04/2023. Mudstone is a really pleasant-grained sedimentary rock consisting of a aggregate of clay and silt-sized particles. Terms including claystone and siltstone are often used in location of mudstone, although these consult with rocks whose grain length falls inside a good deal narrower stages and underneath near exam those ...

Equations for estimating K from grain size commonly use two metrics from a grain size distribution plot: D 10, the grain diameter for which 10% of the sample is finer ... Siltstone: 12: Till, predominantly silt: 6: Till, predominantly sand: 16: Till, predominantly gravel: 16: Tuff: 21: Porosity (n)Normal probability plots of rutilated quartz grain sizes from small scans show that these grains are normally distributed (R 2 = 0.988; p = 10 −33 ).A Method of Inverting Rock Grain Size Based on Nuclear Magnetic Resonance Logging Data and Application Jinbo Wu ,1 Yitao Hu ,2 and Hairong Zhang 3,4 1Zhanjiang Branch of CNOOC Ltd., ... 15 18.7 1.76 Siltstone 29 19.6 16.60 Silty fine sandstone 2 15.8 0.11 Argillaceous siltstone 16 19.9 2.32 Silty fine sandstone 30 20.4 2.07 Siltstone 3 18.1 1 ...Grain size, for example, while a useful property of sandstones, lacks utility for shale because it is too small to be readily discerned. Mineral composition, though unquestionably useful, is again stymied by small grain size. XRD or whole rock chemistry data would be needed to make it workable. In fact, without advanced instrumentation, the ...C)compaction and cementation of rock fragments ranging in size from 0.006 to 0.2 centimeter in diameter D)compaction and cementation of rock fragments ranging in size from 0.0004 to 0.006 centimeter in diameter Which processes produced the brown siltstone layer in outcrops I and II? A)basalt B)limestone C)rock salt D)rock gypsumSiltstone, hardened sedimentary rock that is composed primarily of angular silt-sized particles (0.0039 to 0.063 mm [0.00015 to 0.0025 inch] in diameter) and is not laminated or easily split into thin layers.Grain size analysis is a vital sedimentological tool used to unravel the hydrodynamic conditions, mode of transportation and deposition of detrital sediments. In this study, detailed grain-size analysis was carried out on thirty-five sandstone samples from the Ecca Group in the Eastern Cape Province of South Africa. Grain-size statistical parameters, bivariate analysis, linear discriminate ...Clastic sedimentary rocks are named according to the grain size of the sediment particles. Conglomerate = coarse (64 mm to >256 mm), rounded grains. Breccia = ...6.1 Clastic Sedimentary Rocks. A clast is a fragment of rock or mineral, ranging in size from less than a micron [1] (too small to see) to as big as an apartment block. Various types of clasts are shown in Figure 5.12 and in Exercise 5.3. The smaller ones tend to be composed of a single mineral crystal, and the larger ones are typically ...1) Particle Size: Clay (Very Fine Grained): < 1/256 mm ; Silt (Fine Grained) : 1/256 to 1/16 mm ; Sand (Medium Grained) : 1/16 to 2 mm ; Pebbles (Coarse Grained) : > 2 mm ; Particle size indicates the energy of the transporting medium. The larger the size of grains in a clastic rock, the more energy it took to move that particle to the place of ...

A cup of plain, uncooked rice contains anywhere from 5,000 to 10,000 grains. The number of grains found in a cup of rice varies considerably by the variety of rice, as there are over 40,000 types of rice throughout the world, each of varyin...

Aeolian, sometimes spelled eolian or œolian, are deposits of windblown sediments. Since wind has a much lower carrying capacity than water, aeolian deposits typically consist of clast sizes from fine dust to sand [ 52 ]. Fine silt and clay can cross very long distances, even entire oceans suspended in the air.The term grain size refers to the average particle size within a sedimentary rock. ... siliciclastics are called silt (siltstone for the rock) if the average ...Sedimentary rocks are classified on the basis of the texture (grain size) of the rock, and composition. The basic classification only concerned texture, using the Wentworth size scale.But any full rock name must specify both texture and composition. Thus, an arkose sandstone is a rock of sand sized particles, with a high percentage of …Unconsolidated sandpacks. One laboratory study deserves examination because it illustrates the relationships among grain size, sorting, k, and Φ.Using sand from two Texas rivers, Beard and Weyl sieved 48 sand samples into 8 size classes and 6 sorting classes. Each data point shown in Fig. 4 represents the permeability and porosity of a …23 sept 2023 ... Instead of being rounded, sediments are jagged. “Sandstone” are clastic sedimentary rocks that have compacted sand grains. “Siltstone” is ...Grain size. Particle size is an important textural parameter of clastic rocks because it supplies information on the conditions of transportation, sorting, and deposition of the …Siltstone, mudstone, and claystone implies lithified, or hardened, detritus without fissility. [2] Overall, "mudrocks" may be the most useful qualifying term, because it allows for rocks to be divided by its greatest portion of contributing grains and their respective grain size, whether silt, clay, or mud. 1) Particle Size: Clay (Very Fine Grained): < 1/256 mm ; Silt (Fine Grained) : 1/256 to 1/16 mm ; Sand (Medium Grained) : 1/16 to 2 mm ; Pebbles (Coarse Grained) : > 2 mm ; Particle size indicates the energy of the transporting medium. The larger the size of grains in a clastic rock, the more energy it took to move that particle to the place of ...

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1.1 Definition. Siltstone can be defined as a fine-grained sedimentary rock which mainly consists of consolidated silt. Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles. 1.2 History.Particle size descriptions like sand, silt, and clay have specific meaning in geology and engineering. (see chart below). Shales, mudstones and claystones are rock types that are very similar to each other. Siltstone - greater than half of the composition is silt-sized particles. Claystone - greater than half of the composition is clay-sized ...Silt is a size term used for material that's smaller than sand (generally 0.1 millimeter) but larger than clay (around 0.004 mm). The silt in this siltstone is unusually pure, containing very little sand or clay. The absence of clay matrix makes siltstone soft and crumbly, even though this specimen is many millions of years old.The median grain diameter of reservoir silt is 0.03-0.07 mm. Reservoir silt with a grain size smaller than 0.01 mm accounts for 28%. The degrees of formation damages of water, salt, acid, and alkali sensitivities are strong.D=laminated siltstone grading to mudstone. Graded bedding refers to a sequence of increasingly coarse- or fine-grained sediment layers. Graded bedding often develops when sediment deposition occurs in an environment of decreasing energy. ... Grain size, flow velocity, and flow regime or pattern interact to produce bedforms having unique ...Grain Size Grain Sorting Grain Angularity Layering; Sandstone.06-2 mm: Poor to fair: Angular to subrounded: Usually visible: Siltstone.004-.06 mm: Fair to good: Too small to describe: Not usually visible: Shale <.004 mm: Good: Too small to describe: Usually visible: Mudstone < .004 mm: Good: Too small to describe: Not visible: Conglomerate >2 ... Jan 4, 2018 · Grain Size of Sand Size of Grain (μ) Size of Grain (ϕ) Size of Grain (metric) Very Coarse Upper 1410 - 2000 -0.5 - -1.0 1.4142 - 2.0 mm Very Coarse Lower The detrital grain size of siltstone reservoirs occupies a middle ground between sandstones and shales, both of which are better understood in terms of their petrophysical properties. Because siltstones can be important hydrocarbon reservoirs, we examine controls on petrophysical properties in the Lower Triassic Montney Formation in western ...Clastic rocks are named for their grain size and shape. • Coarse-grained (>2 mm) rocks with rounded grains are called conglomerate. If the coarse-grains are angular, ... They include siltstone and shale. Shale from Grayson County (Photograph by Parvinder Sethi) Fine-grained sediments usually form shale.The term grain size refers to the average particle size within a sedimentary rock. ... siliciclastics are called silt (siltstone for the rock) if the average ...claystone - 1. siltstone - 2. sandstone - 3. conglomerate - 4. Put the sediments shown below in order according to how well sorted they are. List them from well sorted to poorly sorted. PHOTO 1. B, C, A. The rock in the image below contains clasts that are larger than sand and are partially rounded. ….

Grain Size < 1/256 mm. Crystalline, Clastic, or Amorphous: Composition ... indurated mud; includes claystone and siltstone Shale: finely fissile; may include much siltpegmatite, almost any wholly crystalline igneous rock that is at least in part very coarse grained, the major constituents of which include minerals typically found in ordinary igneous rocks and in which extreme textural variations, especially in grain size, are characteristic. Giant crystals, with dimensions measured in metres, occur in some …classifications generally include grain size, type of cement or matrix, mineral composition in order of increasing amounts greater than 15 percent, and the rock type, such as medium-grained, calcite-cemented, feldspathic-quartzose sandstone, and coarse- to fine-grained, lithic-feldspathic-quartzose gray-wacke with an argillaceous-There are various physical properties of Siltstone like Hardness, Grain Size, Fracture, Streak, Porosity, Luster, Strength etc which defines it. The physical properties of Siltstone rock are vital in determining its Siltstone Texture and Siltstone Uses. Hardness and Strength of Siltstone. The physical properties of Siltstone depend on its ...Silt-sized particles range between 0.00015 and 0.0025 inches in diameter, or between 0.0039 and 0.063 millimeters in diameter. They are intermediate in size between coarse clay on the small side and fine sand on the large side. Grain size: Fine- grained. Siltstone Composition. Clastic sedimentary rocks are deposited in three ways. They are water glaciers and wind. Identifying siltstone and shale requires distinguishing between silt and clay particles.Silt and clay are both tiny particles that have weathered away from rocks and minerals. Silt is intermediate in size ...Lab Activity 6.3 - Clastic Sedimentary Rocks. First, you will examine textures that are pertinent specifically to clastic sedimentary rocks by looking at grain sizes, grain rounding, and grain sorting. Next, you will identify materials that are commonly found within clastic sedimentary rocks.Clastic sediments are distinguished on the basis of average grain size. gravel-size particles are larger than 2 mm diameter sand-size particles range in diameter from 1/16 to 2 mm (they feel like sandpaper) silt-size particles have diameters from 1/256 to 1/16 mm (they feel finely gritty)Conglomerate and breccia are made of individual stones that have been cemented together. In conglomerate, the stones are rounded. In breccia, the stones are angular. Sandstone is made of sand-sized particles. Siltstone is made of smaller particles. Silt is smaller than sand but larger than clay. Shale has the smallest grain size. Grain size of siltstone, Grain Size > 2 mm. Clastic Unconsolidated: gravel (rounded), rubble (angular) Consolidated: conglomerate (rounded), breccia (angular) Size Grades (mm): 2-4 …, Siltstone: Floodplain, mudflats, deltas, intermediate-depth sea/lake < 1/256 mm: ... Make brief notes on each hand sample noting color, texture (grain size - whether ..., Medium-grained rocks can be composed of quartz grains, feldspar grains (arkose), or rock fragments and clay (graywacke). Medium-sized grains in clastic sedimentary rocks form sandstone. This sample is a quartz sandstone. • Fine-grained (<1/16 mm) rocks are generally called mudrocks. They include siltstone and shale., Shale, siltstone, sandstone, conglomerate. C. Conglomerate ... Clastic sedimentary rocks are names according to the grain size of the sediment particles., siltstone, hardened sedimentary rock that is composed primarily of angular silt-sized particles (0.0039 to 0.063 mm [0.00015 to 0.0025 inch] in diameter) and is not laminated or easily split into thin layers., Study with Quizlet and memorize flashcards containing terms like 4 steps for Sedimentary Rocks to form, List the following in order from largest to smallest grain size: sand, clay, pebble, cobble, silt, granule, boulder, Boulder size and more., Mar 28, 2023 · Claystone is a clastic form of sedimentary rock. It primarily consists of tiny particles cemented into hard rock with a size of less than 1/256 mm. In terms of size, Claystone is comparable to siltstone and Mudstone. Therefore, Claystone’s formation is similar and useful to Mudstone. A brief idea regarding Claystone fa. , Arenaceous rocks are those rocks, which are made up of particles having a grain size between 0.1 -2 mm diameter. ... Siltstone is a sedimentary rock composed ..., Sedimentary rock - Clastic, Chemical, Organic: The texture of a sandstone is the sum of such attributes as the clay matrix, the size and sorting of the detrital grains, and the roundness of these particles. To evaluate this property, a scale of textural maturity that involved four textural stages was devised in 1951. These stages are described as follows., This works well for gravel-sized clasts, but it may be difficult for finer-grained samples. r Compare the grain size to that of reference sediment textures on a grain-size comparator or sand gauge. This works well for distinguishing sandstone from siltstone. r List whether the sample consists of gravel, sand, silt, or clay particles based on a ..., Multiple Choice. 30 seconds. 1 pt. Although more than 2000 minerals have been identified, 90% of Earth's lithosphere is composed of the 12 minerals listed. The best explanation for this fact is that most rocks. are monomineralic. are composed only of recrystalized minerals. have a number of minerals in common. have a 10% nonmineral composition., raphy. Confusion of grain size and min-eral composition is especially pro-nounced in the usage of the term "gray-wacke," which has been applied indis-criminately to all clayey sandstones (a textural category), regardless of the min-eral composition of the sand portion. In addition to mineral composition and grain size, there is a third important , This rock in the strict scientific usage is on the lower right corner with ash tuff (mean diameter of pyroclasts less than 1/16 mm which is analogous to siltstone). At least 75% of the pyroclastic material of these rocks has a mean diameter less than 2 mm. Lapillistone is mostly composed of lapilli (more than 75%), pyroclastic breccia (agglomerate) are mostly …, Grain sizes are delineated using a logbase-2 scale [9; 10]. For example, the grain sizes in the pebble class are 2.52, 1.26, 0.63, 0.32, 0.16, and 0.08 inches, which correlate respectively to very coarse, coarse, medium, fine, and very fine granules. Large fragments, or clasts, include all grain sizes larger than 2 mm (5/64 in)., Grain size analysis is a common method in the study of sedimentology. For the consolidated sedimentary rocks, the traditional methods are rock slice observation and image analysis. In recent years ..., After removing particles >0.4 mm (No 40 sieve size) mould a pat of soil to the consistency of putty, adding water if necessary. Allow the pat to dry completely by oven, sun or air drying, and then test its strength by breaking and crumbling between the fingers. This strength is a, With the ever-changing dynamics of global agriculture, understanding the factors that influence grain market prices is crucial for farmers, traders, and consumers alike. The supply and demand dynamics play a significant role in determining ..., Mudstone Mudstone is an extremely fine-grained sedimentary rock consisting of a mixture of clay and silt-sized particles. Terms such as claystone and siltstone are often used in place of mudstone, although these refer to rocks whose grain size falls within much narrower ranges and under close examination these are often technically mudstones., Study with Quizlet and memorize flashcards containing terms like __________, a common mineral found in igneous rocks,is the most abundant mineral in detrital sedimentary rocks. a. calcute b.quartz c.orthoclase d.biotite, which major component of detrital sedimentary rocks only rarely occurs as a primary mineral in igneous rocks? a. ferromagnesian minerals b. …, Clastic sedimentary rocks are named according to the characteristics of clasts (rock and mineral fragments) that comprise them. These characteristics include grain size, shape, and sorting. The different types of clastic sedimentary rocks are summarized in Figure 9.5. Figure 9.5 Types of clastic sedimentary rocks., C)compaction and cementation of rock fragments ranging in size from 0.006 to 0.2 centimeter in diameter D)compaction and cementation of rock fragments ranging in size from 0.0004 to 0.006 centimeter in diameter Which processes produced the brown siltstone layer in outcrops I and II? A)basalt B)limestone C)rock salt D)rock gypsum , Why is grain size important? Siliciclastic sedimentary rocks are the result of erosion, transport, and deposition. The grain size of a sediment reveals important information …, Grain Size Grain Sorting Grain Angularity Layering; Sandstone.06-2 mm: Poor to fair: Angular to subrounded: Usually visible: Siltstone.004-.06 mm: Fair to good: Too small to describe: Not usually visible: Shale <.004 mm: Good: Too small to describe: Usually visible: Mudstone < .004 mm: Good: Too small to describe: Not visible: Conglomerate >2 ..., Siltstone. A siltstone is a lithified, nonfissile mudrock. In order for a rock to be named a siltstone, it must contain over 50% silt-sized material. Silt is any particle smaller than sand, 1/16 of a millimeter, and larger than clay, 1/256 of millimeter. Silt is believed to be the product of physical weathering, which can involve freezing and ... , Grain size is a good indicator of the energy or force required to move a grain of a given size. Large sediments such as gravel, cobbles, and boulders require more energy to move than smaller sand, silt, and clay sized sediments. Grain size is also an indicator of the distance or length of time the sediments may have traveled. , Grain size analysis is a common method in the study of sedimentology. For the consolidated sedimentary rocks, the traditional methods are rock slice observation and image analysis. In recent years ..., Silt is defined as grains 2–62 μm in diameter, or 4 to 8 on the Krumbein phi (φ) scale. [7] An alternate definition is that siltstone is any sedimentary rock containing 50% or more of silt-sized particles. [8] , The term grain size refers to the average particle size within a sedimentary rock. ... siliciclastics are called silt (siltstone for the rock) if the average ..., Grain size distribution of the slaked material retained in 2 mm-mesh drum ... Siltstone-. 3. All pieces remained intact. All pieces remained intact. All pieces ..., Fine-Grained Clastic Rocks. Rock composed of at least 75% silt- and clay-sized clasts is called mudrock (Figure 5.5, bottom row). If a mudrock shows evidence of fine layers (laminations) and breaks into sheets, it is called shale.Otherwise, it is siltstone (dominated by silt), mudstone (a mix of silt and clay), or claystone (dominated by clay). The fine …, It is used to define loose granular particles falling in a specific size range. The silt particles have a diameter range between 0.00015 and 0.0025 inches. The silt in the siltstone doesn't have a fixed composition. Its properties vary from place to place, but it is usually composed of micas, clay minerals, feldspars, and quartz. Siltstone ..., Silt forms fine-grained siltstone, with fragments between 1/16 mm and 1/256 mm. Anything less than 1/256 mm results in either claystone or mudstone. Two types of mudstone are shale and argillite, which is shale that has undergone very low-grade metamorphism., raphy. Confusion of grain size and min-eral composition is especially pro-nounced in the usage of the term "gray-wacke," which has been applied indis-criminately to all clayey sandstones (a textural category), regardless of the min-eral composition of the sand portion. In addition to mineral composition and grain size, there is a third important