sedimentary rocks and WES study Geet Patel

What are the two types of sedimentary rock?

clastic and non clastic

Clastic sedimentary rock?

o   Rocks made of sediments of pre-existing rocks.

o   We can further classify by sediment size (gravel, sand, silt, clay)

Non clastic two types of….

chemical and biological

chemical non clastic sedimentary rock?

o   - These rocks are made of dissolved sediments that precipitate out of water

§  Mostly inorganic

§  Ex: chemical limestone, chalk

biological non clastic sedimentary rock

o   (Organic) - Rock forms from biological (living) sources, such as stratified remains of plant material or carbonate shelled organisms.

§  Ex: coal is from swamp plants and coquina is from shells

strata?

·         - If undisturbed sedimentary rock is put down in layers.

fossils?

Remains or traces of ancient life

ripple marks?

Tells you that the rock was formed where there was moving water.

mud cracks?

Tells you that the rock was formed as sediments were drying out.

weathering?

The breaking of rock into smaller pieces (sediments).

erosion?

·         Movement of sediments.

deposition?

The dropping of sediments.

Mechanical weathering?

(Also called physical weathering); Breaking down of rock into smaller pieces without changing the chemistry of the rock

chemical weathring?

·         Chemical reactions cause rock to break down, the chemistry of the rock has changed.

wind physical weathering?

sand dunes

water physical weathering?

waves and rivers

exfoliation physical weathering?

glaciers

ice physical weathering?

frost wedging is when water gets into crevices and expands

plant action physical weathering?

like frost wedging but with plant roots

pressure unloading physical weathering?

when a top layer of rock is scraper off it relieves pressure and rock underneath expands

oxidation (chemical weathering)

rusting of iron

carbonation (chemical weathering)

caves and caverns

lichens (chemical weathering)

can grow on rocks and release enzymes to break them down

what do rivers do for erosion, weathering, and depositon?

erode the banks.

o   Over time a river bends more and more.

Oxbow lakes are loops completely cut off.

what do glaciers do for erosion, weathering, and depositon?

As a glacier moves the surface is scratched and rocks can be moved large distances.

what do river deposits do for erosion, weathering, and depositon?

o   Flood Plain - Areas on banks of rivers that get flooded.

o   Delta - Fan/triangle shaped deposit at mouth of river.

o   Alluvial Fan - Fan shaped deposit at base of mountain.

what do ocean waves do for erosion, weathering, and depositon?

• hit the land it causes weathering, erosion, and deposition.

what does wind do for weathering eriosn and deposion?

o   Sand dunes are in areas of high wind erosion.

o   Dunes can change shape.

soil?

·         Soil is a product of weathering, erosion and deposition.

·         Soil contains sediments, organic material called humus, water, and air.

·         Soil sits on top of bedrock

succession?

·         Soil is created over time as solid bedrock is exposed to weathering forces.

·         As the bedrock breaks down more and more living things come and add varying organic matter.

·         Soil is constantly changing!

soil horizons word?

OABCD

horizion o?

·         organic matter/humus

horizon a

·         topsoil, rich dark and at surface

horizon B

·         - subsoil, clay that fell from above layer

horizon c

·         partially weathered bedrock

horizon d

·         solid bedrock, parent material

how is soil determind?

·         Soil is determined by parent material, time, climate, organisms and slope.

causes of soil erosion?

o   Agriculture and Overgrazing, Construction, Logging and Mining

solutions to soil erosion?

o   Windbreaks, Contour Farming, Strip Farming, No Till Farming

what is a rotation?

·          

24 hours

what is a revolutions?

365.5 days

axis tilt?

(23.5)=seasons

Igneous rock cycle?

= cooling and hardening of magma/lava (molten rock)

sedimentary rock cycle?

weathering + erosion → sediments → compaction + cementing

metamorphic rock cycle?

o   = heat + pressure