Pt 1 Sedimentary Rocks

Question 1

Diagenesis-
Everything that happens to a rock from the time it is created until the time it is destroyed, think of it as the life ________ of the rock

Answer 1

cycle

Question 2

Compaction-
Sediment is squeezed together to make a ______

Answer 2

rock

Question 3

Cementation- chemical precipitate around grains of rock or ____________ or pieces of organic debris such as shells or bones, and the chemical form a “glue” that holds the grains together

Answer 3

minerals

Question 4

3 most common cements are: Calcium Carbonate, Silica, and _________

Answer 4

rust

Question 5

Lithification- “Lith” is a Greek word meaning ______, so this is literally the process of sediments or organic matter being turned to stone

Answer 5

rock

Question 6

Classification- How we describe types of sedimentary rocks

Question 7

Detrital- rocks made from _________ of other rock

Answer 7

pieces

Question 8

Chemical- Rocks made from chemicals precipitated from ________, either with or without help from life

Answer 8

water

Question 9

Texture-

Clastic = made of pieces(all detrital rocks & some chemical rocks)

Chemical = precipitated from water

Question 10

Detrital Sedimentary Rocks-

Conglomerate, Breccia, Sandstone, Siltstone, Claystone

Question 11

Chemical Sedimentary Rocks-

Crystalline Limestone, Micrite, Travertine, Coquina, Fossiliferous Limestone, Chalk, Gypsum, Rock Salt, Coral

Question 12

Conglomerate (Detrital)- notice the ____________ grains

Answer 12

rounded

Question 13

Breccia (Detrital)- angular ________

Answer 13

grains

Question 14

Sandstone (Detrital)- Mesa, Zion National _______

Answer 14

park

Question 15

Chemical Rocks __organic-

Crystalline Limestone, Travertine and Micrite

Answer 15

In

Question 16

Chemical Rocks Organic-
____________ , Fossiliferous limestone and chalk

Answer 16

Coquina

Question 17

Chemical Rocks-
- Chert, Flint, ________, Agate

Answer 17

Jasper

Question 18

Chemical Rocks (Evaporites)-

Halite & Gypsum

Question 19

Coal is an Organic Rock

Question 20

Coal process-
- forms in swamps
-starts out as low grade Peat
-Then through compaction it forms Lignite
-Then Bituminous coal and finally w/metamorphism high grade Anthracite coal-(grade refers to how much energy the material emits when burned)

Question 21

Depositional Environments-
sedimentary rocks may be:

Extrabasinal in origin: formed from ____________ of pre-existing rocks outside of basin & transported to environment of deposition

Intrabasinal in origin: formed inside the basin; includes chemical precipitates, most carbonate rocks, and coal

Answer 21

weathering

Question 22

Depositional Environments-

Facies: Characteristic of a particular _____ unit, which we can use to interpret the depositional environment

Answer 22

rock

Question 23

Depositional Environments-

Continental- environment on land including lakes

Transitional- envir. along the contact between ocean & land

Marine- envir. ocean

Question 24

Marine Depositional Environments-

1. Continental shelf
2. ____________ slope
3. Continental rise
4. Abyssal plain

Answer 24

Continental

Question 25

Continental Shelf- Flooded edge of continent. Flooding occurred when glaciers melted about 10,000 years ago. a. relatively flat b. shallow water c. may be up to 300 km wide d. exposed to waves, tides and currents e. covered by sand, silt, and clay f. larger sedimentary grains are deposited closer to shore g. locally cut by submarine canyons h. coral reefs and carbonate sediments may accumulate in tropical areas

Question 26

Continental Slope- the steeper slope at edge of continent a. located seaward of continental shelf b. edge of continental plate, it's where continental & oceanic crust meet c. May be about 20 km wide unless it boarders a subduction zone in which case it may be narrower d. deeper water e. more steeply inclines f. rapid sediment transport down slop by dense, muddy turbidity currents g. passes seaward to the continental rise

Question 27

Continental Rise- At the base of the continental slope a. more gradual incline than the slope b. may be hundreds of km wide c. water depths of 1400 to 3200 m d. submarine fans form off submarine canyons e. turbidity currents transport sediment downslope from continental shelf as turbidites-those underwater landslides f. passes seaward into abyssal plains

Question 28

Deep Marine Realm- Abyssal Plains (deep ocean floor) a. nearly flat b. water depths fo 3 to 5 km c. covered by very fine-grained sediment & shells of microscopic organisms - clay -volcanic ash -Foraminifera -Coccolithophores -radiolarians -diatoms

Question 29

Transitional Depositional Environments- environments at or near the transition between land & sea 1. Deltas-accumulations of sediment where rivers meet ocean 2. Beaches & barrier islands- sand accumulating along margins of oceans sometimes due to the presence of ancient beach dunes 3. Lagoons- protected areas of calm water 4. Tidal flats- low lying areas of coast that are covered by water at high tide & exposed at low tide exposed 5. Estuaries- drowned river mouths, areas where seawater extends into a coastal river channel

Question 30

Deltas- a. fan-shaped accumulations of sediments names for the shapes of the greek letter "Delta" which looks like a triangle b. formed where a river flows into a standing body of water, such as a lake or the sea c. coarser sediment tends to be deposited near the mouth of the river; finer sediments is carried seaward & deposited in deeper water d. delta builds seaward as sediment is deposited at the river mouth

Question 31

Beaches & barrier Islands- a. shoreline deposits (sand) b. exposed to wave energy c. dominated by sand d. marine fauna lives in both the lagoon & seaward side e. few km or less in width but may be more than 100 km long f. separated from mainland by a lagoon g. may be associated with tidal flat deposits

Question 32

Lagoons- a. Protected bodies of water, often on the landward side of barrier islands b. Protected from the pounding of the ocean waves by barrier islands or other landforms c. Contains finer sediment than the beaches (usually silt and clay) d. Lagoons are also commonly present behind reefs, or in the center of atolls.

Question 33

Tidal Flats - Nearly flat, low relief areas that border lagoons, shorelines, and estuaries - Periodically flooded and exposed by tides (often twice each day) - May be cut by meandering tidal channels - May be marshy, muddy, sandy or mixed sediment types (terrigenous or carbonate) - Laminations and ripples are common - Sediments are intensely burrowed - Stromatolites may be present (if conditions are appropriate)

Question 34

Estuaries Mouth of a river drowned by the sea Often brackish (mixed fresh & salt) water May trap large volumes of sediment Sand, silt, and clay may be deposited depending on energy level Many estuaries formed due to sea level rise as glaciers melted at end of last Ice Age Some formed due to tectonic subsidence, allowing sea water to migrate upstream

Question 35

Continental Environments Rivers or fluvial environments Alluvial fans Lakes (or lacustrine environments) Glacial environments Aeolian environments

Question 36

Fluvial Environments Braided (shaped like braided hair) and meandering (curving) river and stream systems Rivers have deeper channels, sand/gravel bars, levees (hills of sediment on either side of the river), and floodplains (areas that flood when a river overflows it’s banks) Channel deposits are coarse, rounded gravel, and sand Bars are sand or gravel Levees are fine sand or silt Floodplains are covered by silt and clay (called overbank deposits) because they formed “over the bank” of the river

Question 37

Lacustrine Environments (Lakes) May be large or small May be shallow or deep Filled with terrigenous, carbonate, or evaporitic sediments Sediments are typically fine grained but may be coarse near the edges Fine sediment and organic matter settling in some lakes produced laminated oil shales Playa lakes are shallow, temporary lakes that form in arid regions. They periodically dry up as a result of evaporation