A dark-colored soil layer that is rich in organic matter and high in biological activity by animals and plants.
B horizon (zone of accumulation)
The clayey layer stained red or brown by hematite and limonite because of the leaching of chemicals where a hard layer of Earth material "hardpan" can form.
A parent material that lies below B horizon that is subjected to mechanical and chemical weathering.
The decomposition of rock from exposure to water and atmospheric gases like Co2 and O2 that then form new chemical compounds.
A hydrous aluminum silicate with a sheet-silicate structure resulting from weathering of the mineral feldspar.
Describes the tendency for different types of rock to weather at different rates
E horizon (zone of leaching)
A pale and sandy layer that has organic acids and carbon dioxide produced by decaying plants in the topsoil which through water moves down to.
Picking up/physically removal of rock particles by running water or glaciers resulting from weathering.
The mechanical process of spalling off or rock layers (like peeling layers off an onion).
Large, rounded landforms that develop in massive rock by exfoliation
The mechanical effect of freezing water on rocks as frost wedging or frost heaving.
As the ground freezes, ice forms first under large rock fragments in the soil pushing boulders out of the ground as well as soil vertically.
When water trickles into cracks (joints) in a rock and freezes, expanding and breaking rocks into pieces.
The mineral iron oxide formed from weathering or "rust"
The mineral iron oxide combined with water from weathering or "rust"
A type of soil that is well-drained, may contain organic matter and has approximately equal parts of: sand, silt, and clay.
Physical disintegration where there are several processes that break rock into smaller pieces.
The uppermost layer or soil horizon that consists entirely of organic material.
A type of mechanical weathering where a body of rock can crack due to the reduction of pressure.
Soil that develops directly from weathering of the rock below.
cracks on a rock that develop parallel to the outer surface of the rock as it expands more than the inner part.
Layer of weathered, unconsolidated material that contains organic matter and is capable of supporting plant growth.
Soil layers distinguished by appearance and chemical composition
Where rock has been rounded by weathering from an initial blocky shape
(Ch. 12) The movement of eroded particles by agents such as rivers, waves, glaciers or wind.
Soil not formed from the local rock but from parent material brought in from some other region and deposited by water, wind or glaciers.
Processes that change the physical and chemical character of moving or stationary rocks at our near the surface.
A large, fan-shaped pile of sediment that usually forms where a stream's velocity decreases as it emerges from a narrow canyon onto a flat plain at the foot of a mountain range.
An arrangement of layers or beds of rock.
A nearly flat surface separating two beds of sedimentary rock.
The solid material that precipitates in the pore space of sediments, binding the grains together to form solid rock.
The chemical precipitation of material in the spaces between sediment grains, binding the grains together into a hard rock.
chemical sedimentary rocks
A rock composed of material precipitated directly from solution.
A hard, compact, fine-grained sedimentary rock formed almost entirely of silica.
An arrangement of rock fragments bound into a rigid network by cement.
Sediment composed of particles with diameter less than 1/246 millimeters.
A sedimentary rock formed from the consolidation of plant material. It is rich in carbon, usually black, and burns readily.
A loss in overall volume and pore space of a rock as the particles are packed closer together by the weight of overlying material.
A coarse-grained sedimentary rock (grains coarser than 2 millimeters) formed by the cementation of rounded gravel.
Boundary surface between two different rock types or ages of rocks.
An arrangement of relatively thing layers of rock inclined at an angle to the more nearly horizontal bedding planes of the larger rock unit.
An arrangement of interlocking crystals.
Crystal development and growth.
The settling or coming to rest of transported material.
detrital sedimentary rocks
A sedimentary rock composed of fragments of preexisting rock.
A sedimentary rock composed mostly of the mineral dolomite.
environment of deposition
The location in which deposition occurs, usually marked by characteristic physical, chemical, or biological conditions.
Rock that forms from crystals precipitating during evaporation of water.
A body of rock of considerable thickness that has a recognizable unity or similarity making it distinguishable from adjacent rock units.
Traces of plants or animals preserved in rock.
A single bed with coarse grains at the bottom of the bed and progressively finer grains toward the top of the bed.
Rounded particles coarser than 2 millimeters in diameter.
A sedimentary rock composed mostly of calcite.
The consolidation of sediment into sedimentary rock.
Fine-grained material found in the pore space between larger sediment grains.
Polygonal crack formed in very fine-grained sediment as it dries.
organic sedimentary rock
Rock composed mostly of the remains of plants and animals.
The deposition of most water-laid sediment in horizontal or near-horizontal layers that are essentially parallel to the Earth's surface.
The total amount of space taken up by openings between sediment grains.
The development of new crystals in a rock, often of the same composition as the original grains.
Any of the small ridges formed on sediment surfaces exposed to moving wind or water. The ridges form perpendicularly to the motion.
The grinding away of sharp edges and corners of rock fragments during transportation.
Sediment composed of particles with a diameter between 1/16 and 2 millimeters
A medium-grained sedimentary rock formed by the cementation of sand grains.
Loose, solid particles that can originate by 1) weathering and erosion of preexisting rock 2) chemical precipitation from solutions, usually water 3) secretion of organisms.
Rock that forms from 1) lithification of any type of sediment 2) precipitation from solution 3) consolidation of the remains of plants and animas.
A coarse-grained sedimentary rock (grains coarser than 2 milimeters) formed by the cementation of angular rubble.
A feature found within sedimentary rocks, usually formed during or shortly after deposition of the sediment and before lithification.
A fine-grained sedimentary rock (grains finer than 1/16 millimeter in diameter) formed by the cementation of silt and clay (mud). Shale has thin layers (laminations) and an ability to split (fissility) into small chips.
Sediment composed of particles with a diameter of 1/256 to 1/16 millimeters.
Process of selection and separation of sediment grains according to their grain size (or grain shape or specific gravity)
The locality that eroded to provide sediment to form a sedimentary rock.
A principle or law stating that within a sequence of undisturbed sedimentary rocks, the oldest layers are on the bottom, the youngest on top.
A flowing mass of sediment-ladem water that is heavier than clear water and therefore flows downslope along the bottom of the sea or lake.
A stress due to a force pushing together on a body
Pressure applied equally on all surfaces of a body aka "lithospheric pressure"
Metamorphism under conditions in which high temperature is the dominant factor.
When pressures on a body are not of equal strength in all directions.
Something capable of being molded and bent under stress.
Parallel alignment of textural and structural features of a rock.
A metamorphic rock composed of light and dark layers or lenses.
A fine-grained, unfoliated metamorphic rock
Rock deposited by precipitation of ions from solution in hot water.
A line along which the temperature of rock (or other material) is the same.
A coarse-grained rock composed of interlocking calcite (or dolomite) crystals.
A rock produced by metamorphism.
The transformation of preexisting rock into textually or mineralogically distinct new rock as a result of high temperature, high pressure, or both but without the rock melting in the process.
Metamorphism coupled with the introduction of ions from an external source.
Mixed igneous and metamorphic rock.
Original rock before being metamorphosed.
A metamorphic rock in which clay minerals have recrystallized into microscopic micas, giving the rock a silky sheen.
A rock composed of sand-sized grains of quartz that have been welded together during metamorphism.
Metamorphism that takes place at considerable depth underground.
A metamorphic rock characterized by the coarse-grained minerals oriented approximately parallel.
Movement in which parts of the body slide relative to one another and parallel to the forces being exerted.
A fine-grained rock that splits easily along flat, parallel planes.
A force acting on a body, or a rock unit, that tends to change the size or shape of that body, or rock unit. Force per area within a body.
Quartz or other minerals that have been deposited in a crack by hot fluids.