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Tessellated pavement – Relatively flat rock surface that is subdivided into more or less regular shapes by fractures; Truncated spur – Ridge that descends towards a valley floor or coastline that is cut short; Tor – Large, free-standing rock outcrop on a gentle hill summit
Most commonly this takes the form of normal grading, with coarser sediments at the base, which grade upward into progressively finer ones. Such a bed is also described as fining upward . [ 1 ] Normally graded beds generally represent depositional environments which decrease in transport energy (rate of flow) as time passes, but these beds can ...
Detritus (/ d ə ˈ t r aɪ t ə s /; adj. detrital / d ə ˈ t r aɪ t əl /) is particles of rock derived from pre-existing rock through weathering and erosion. [1] A fragment of detritus is called a clast. [2] Detrital particles can consist of lithic fragments (particles of recognisable rock
Also called Indianite. A mineral from the lime-rich end of the plagioclase group of minerals. Anorthites are usually silicates of calcium and aluminium occurring in some basic igneous rocks, typically those produced by the contact metamorphism of impure calcareous sediments. anticline An arched fold in which the layers usually dip away from the fold axis. Contrast syncline. aphanic Having the ...
Glacial abrasion is the surface wear achieved by individual clasts, or rocks of various sizes, contained within ice or by subglacial sediment as the glacier slides over bedrock. [9] Abrasion can crush smaller grains or particles and remove grains or multigrain fragments, but the removal of larger fragments is classified as plucking (or ...
A clast is a fragment of geological detritus, [1] chunks, and smaller grains of rock broken off other rocks by physical weathering. [2] Geologists use the term clastic to refer to sedimentary rocks and particles in sediment transport , whether in suspension or as bed load , and in sediment deposits.
The edge is then sharpened by freeze-thaw weathering, and the slope on either side of the arête steepened through mass wasting events and the erosion of exposed, unstable rock. [3] The word arête is French for "edge" or "ridge"; similar features in the Alps are often described with the German equivalent term Grat.
Also in South Africa, diamonds are often mined from a matrix of weathered clay-like rock called "yellow ground". The matrix of sedimentary rocks is finer-grained sedimentary material, such as clay or silt, in which larger grains or clasts are embedded. It is also used to describe the rock material in which a fossil is embedded.