| The sedimentary clasts also contain abundant opaque minerals, chiefly magnetite. |
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| The cobbles are dominated by pink quartzite, red sandstone and vein quartz, with minor granite clasts near the contact and rare green clasts. |
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| The second unit found immediately above beach level consists of deformed laminated sand and mud containing clasts up to 10 cm across. |
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| The limestone clasts contain rudist fragments and larger foraminifera that indicate erosion from the Campur Formation. |
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| Furthermore, it is not always clear whether fossils from a given locality are from in situ rocks or from spoil or clasts in glacial drift. |
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| The metaconglomerates comprise monocrystalline or polycrystalline angular or subrounded clasts of quartz embedded in an arenaceous matrix. |
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| Except for a few small bone fragments, no fossils have been observed within the clasts or in the matrix. |
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| Interstices are filled with poorly sorted pebble-sized clasts and the matrix content is rather low. |
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| Compositionally, the turbidites are mostly feldspathic litharenites with trace amounts of serpentinite, anorthosite and mafic volcanic clasts. |
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| It consists of clasts of angular to rounded quartz, plagioclase, tourmaline and rock fragments, up to 3 mm in diameter. |
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| The average size of bioclasts is 2-3 cm. Small volcanic clasts appear dispersed in some beds. |
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| During intervening dry periods, winds scour the fan surfaces and sandblast exposed gravel clasts to produce smooth faceted ventifacts. |
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| Further up the core into the Waulsortian sequence, the limestones are cleaner and the breccia clasts are cemented by calcite. |
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| Imbricated clasts indicate eastward palaeocurrents away from the metamorphic complex. |
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| Conglomerate tests are applied to mechanically disaggregated clasts of a formation whose palaeomagnetism is under investigation. |
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| Geochemical analyses of these clasts show that the eruption tapped two chemically distinct rhyolitic magmas. |
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| The clasts in volcaniclastic rocks may range from fine ash to bombs and enormous blocks. |
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| The siltstones contain poorly sorted angular fragments of quartz, and angular clasts and cleavage fragments of plagioclase and alkali feldspar. |
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| The conglomerates contain a mixture of basement-derived clasts and large Upper Permian limestone clasts. |
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| Little-weathered grains of hypersthene and rare clasts of limestone persist throughout the profile, as evidence for limited chemical weathering. |
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| Basal erosion surfaces are locally overlain by a grey pebble-sized lag of mud chip and pedogenic carbonate clasts. |
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| The presence of clasts with flatiron shapes and rare striations in the conglomerate facies is consistent with a glacial setting. |
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| Most beds are almost monomictic, comprising quartz-feldspar porphyry clasts, whereas some other beds are highly heterogeneous. |
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| Coarser fractions additionally contain volcanic clasts of vesicular and porphyritic lava, tuff and pumice. |
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| They contain some quartzite and quartz clasts and only a little debris derived from local Jurassic rocks. |
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| A thin conglomerate, with Miocene carbonate clasts bored by bivalves, and volcanic cobbles, occurs at the base. |
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| Howardites are polymict breccias composed of angular clasts of eucrites and diogenites welded together by pulverized mineral dust. |
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| Well-rounded clasts include lava, volcaniclastic sandstones and bioclastic limestones with nummulites, bryozoa, microbial carbonate and bivalve material. |
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| In the case of more intense Fe impregnation, scattered quartz clasts supported by a ferruginous matrix may be the only remains of former sandstone. |
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| Burrows, mudstone clasts and symmetric, wave ripples are locally present. |
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| Both mineral elongation lineation and striae are observed in clasts. |
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| It is dominated at the exposure by angular quartzite clasts up to 40 cm long with subordinate, subroundcd sandy dolomite, angular micaceous siltstone and limestone clasts. |
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| Conglomerate clasts are principally volcanic rocks and greenish gray chert, with subordinate arkose, graywacke, siltstone, red chert, quartzite, white quartz, and limestone. |
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| Other fragments of igneous rock occur rarely and include granite, volcanic acidintermediate clasts with aphanitic texture and rounded fragments of silicified ash. |
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| The sedimentary beds are composed mainly of poorly sorted subangular to rounded clasts of felsite and rhyolite porphyry that are typically a red color. |
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| This is substantiated by the presence of eroded Permian carbonate clasts. |
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| Boulder sized clasts are found in some sedimentary rocks, such as coarse conglomerate and boulder clay. |
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| Sandstone clasts are most commonly feldspathic, with medium-to-coarse arkosic texture. |
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| According to Hallet, large rocks, or clasts, commonly freeze up through the soil. |
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| However, the apparent lack of the dolomite in the shale clasts precludes their identification as Lower Silurian Estill Shale. |
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| Shale clasts occur within this sandstone unit, and very small, deformed shale clasts between sand grains may have been identified as matrix. |
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| Coquina, a rock composed of clasts of broken shells, can only form in energetic water. |
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| Soil sampled in the tunnel was very moist and sandy and contained large clasts of volcanic tuff. |
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| The subjacent Bryantsville Breccia has subaerial laminar crust enclosing micrite tidal clasts. |
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| The framework of the sediments consists of silty to coarse pebbly, poorly-sorted clasts which are subangular to subrounded and have low sphericity. |
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| The 3D orientation of the clasts is called the fabric of the rock. |
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| Larger, heavier clasts in suspension settle first, then smaller clasts. |
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| In hand specimen, leached, oxidized, and sheared San Diego breccia consists of cobble to boulder sized, sub-rounded aphanite clasts in a dark gray, amorphous silica matrix. |
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| These clasts are essentially ophiolitic consisting of serpentine, olivine, pyroxenes, plagioclase and amphiboles with minor of cherty made up of microquartz and mega quartz. |
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| Plagioclase is commonly the only feldspar phyric phase in the felsic to intermediate volcanic clasts, including lapilli and vitric tuff and probable ash-flow tuff. |
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| Many of these clasts are also clearly phyllitic with sericitic groundmass. |
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| Thinly bedded pea gravel consisting of black chert and metaquartzite clasts are commonly associated with indurated sandstones and orthoquartzites. |
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| Furthermore, many of the clasts within the matrix consisted of metamorphic rocks including green slate, pyroxenite, metaperidotite, metadolerite, and amphibolite. |
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| Bulk samples collected from the profile were sieved into five size fractions to separate rock clasts and Fe nodules of different sizes from the fine earth fraction. |
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| In some instances, individual internally laminated clay clasts can be seen that appear to have fallen into the burrow when it was open and are randomly oriented. |
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| Lenticular goethite-enriched interlayers of conglomerate often occur, in which clasts of siltstone and silty claystone are enclosed into sandy matrix. |
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