Chapter 6 Flashcards
detrital Sediments
Weathering and erosion of pre-existing rocks
Chemical Sediments
Precipitation from solution, including, secretion by organisms in water.
Unconsolidated
The grains are separated or unattached from one another.
Sorting
The process by which sediment grains are selected and separated according to grain size.
deposition
When transported material settles.
Environment of Deposition
The location in which deposition occurs, usually marked by characteristic physical, chemical or biological conditions.
Cement
The solid material that fills in the gaps in sand t glue it all together
What are the three types of sedimentary rocks?
Detrital
Chemical
Organic
lithigication
the processes by which sediment is turned into sedimentary rock.
What are two common minerals that often act as a cement in sedimentary rocks?
Silica.
Calcite.
Chemical Sedimentary Rocks.
A rock composed of material precipitated directly from solution.
Organic Sedimentary Rocks
Rocks that are composed of organic carbon compounds. Coal would be an example.
What are Terrigenous Clastic Rocks?
Detrital Sedimentary rocks.
What is a matrix in sand stone?
Fine-grained material found in the pore space between larger sediment grains.
What are Detrital Rocks made up of?
Quartz and Feldspar
Clay minerals
rock fragments.
What is a dolostone
A sedimentary rock composed mostly of the mineral dolomite
What are the two types of limestone?
biochemical and inorganic
What are evaporites
The general term used for any rock formed from crystals that precipitates from saline water in hot, arid climates.
What is Recrystallization?
A common occurrence in limestone, in which new calcite crystals are developed under the weight of overlying sediment.
What kind of sedimentary rock is coal?
Organic Sedimentary.
What is a bedding plane?
A nearly flat surface separating two beds of sedimentary rock.
What are graded beds in sand dunes?
A single bed with coarse grains at eh bottom bed and progressively finer grains toward the top of the bed.
Turbidity Current
A turbulently flowing mass of sediment-laden water that is heavier than clear water and therefore flows downslope along the bottom of the sea or a lake.
Mud cracks
Polygonal crack formed n very fine-grained sediment as it dries.
What is Original Horizontality
The deposition of most water-laid sediment in horizontal or near-horizontal layers that are essentially parallel to earth surface
what are cross beds?
an arrangement of relatively thin layers of rock inclined at an angle to the more nearly horizontal bedding planes of the larger rock unit. Long story short the layers are not parallel to the earth.
Fossils
The remains of organisms preserved in sedimentary rock.
What is a formation
A body of rock of considerable thickness aht is large enough to be mappable, and with characteristics that distinguish it from adjacent rock. Long story short they use it to learn about the geology of the area.
What is a transgression?
When sea levels rise or the land subsides, causing large continental areas to be flooded.
what is fissility
The ability of a rock to break along a plane.
What is the source area?
The area that a sediment was eroded from a sedimentary rock.
What is a clastic texture?
An arrangement of rock fragments bound into a rigid network by cement.
what is chert?
A hard, compact, fine-grained sedimentary rock formed almost entirely of silica.
What is shale made up of?
Silt and Clay
What is Sedimentary Breccia
A coarse-grained sedimentary rock formed by the cementation of course, angular fragments of rubble.
What is an Alluvial Fan?
A large fan-shaped pile of sediment that usually forms were a stream’s velocity decreases as it emerges from a narrow canyon onto a flat plain at the foot of a mountain range.
