Chapter 6 Section 3 - Sedimentary Rock

What are some types of clastic sedimentary rock?

Breccia, conglomerate, sandstone, siltstone, shale

Sedimentary rock that forms when ions from dissolved minerals precipitate out of water because of the changing concentrations of chemicals is called?

Chemical sedimentary rock

Describe how chemical and organic sedimentary rocks form, and give two examples of each.

Chemical sedimentary rocks form when dissolved minerals precipitate out of water because of changing concentrations of chemicals. Organic sedimentary rock is rock that forms from the remains of living things.

How does the speed with which the sediment is moved affect that sediment?

It affects the size of sediment particles that can be carried and the distance that the particles move

What happens to sediment as it is moved from one place another?

Its characteristics change as it is physically broken down or chemically altered

Sedimentary rock that forms from the remains of plants and animals is called_?

Organic sedimentary rock

Compare the histories of rounded, smooth rocks and angular, uneven rocks.

Smooth Traveled far from source Rough Has not traveled far from source

Explain how the physical characteristics of sediments change during transport.

Sorting and angularity Sediments are transported by the four main agents water, ice, wind, and the effects of gravity. The speed with which the agent of erosion moves affects the size of sediment particles that can be carried and the distance that the particles will move.

What 3 factors determine the characteristics of sedimentary rock?

Source of sediment Way the sediment was moved conditions under w

Identify seven features that you can use to identify the depositional environment in which sedimentary rocks formed.

Stratification Cross-beds Graded bedding Ripple marks Mud cracks Fossils concertions

What 2 factors determine the physical characteristics of sediments?

The distance the sediment is moved and the agent that moves the sediment

In general, how do sediment particles that travel long distances differ from those that travel short distances?

The farther sediment travels from its source, the finer and smoother the particles of sediment become

Cementation

The process in which minerals precipitate into pore spaces between sediment grains and bind sediments together to form rock

Compaction

The process in which the volume and porosity of a sediment is decreased by the weight of overlying sediments as a result of burial beneath other sediments

When marine organisms die, their shells eventually become_?

limestone

Describe how clastic sedimentary rock differs from chemical and organic sedimentary rock.

Clastic sedimentary rock forms when fragments of preexisting rocks are compacted together. Organic sedimentary rock forms from the remains of plants or animals. Chemical sedimentary rock forms when minerals precipitate from a solution or settle from a suspension.

What are some types of organic sedimentary rock?

Coal, dolomites, limestones

What are the two main processes that convert loose sediment to sedimentary rock?

Compaction cementation

Explain how the process of compaction and cementation form sedimentary rock.

Compaction is the process in which sediment is squeezed and in which the size of the pore space between sediment grains is reduced by the weight and pressure of overlying layers. Cementation is the process in which sediments are glued together by minerals that are deposited by the bodies of water.

Which of the following would most effectively sort sediments: a fast-moving river or a small, slow-moving stream?

Fast river because of its power to move the sediment

How are geodes formed?

Geodes are created in the hollow areas of soil such as animal burrows or tree roots. They are also formed in the bubbles in volcanic rock. Over time, dissolved minerals seep into a hollow area and harden into an outer shell creating the geode

Two examples of evaporates are _?

Gypsum halite

Define sediment.

Loose fragments of rock, minerals, and organic material that result from natural processes, including the physical breakdown of rocks

How are concretions formed?

Minerals within a rock segregate and begin to precipitate within cracks and cavities, or as a sediment builds up in successive layers around a nucleus such as a shell or pebble

How are fossils formed?

Most are formed when a plant or animal dies in a watery environment and is buried in mud and silt. Soft tissues quickly decompose leaving the hard bones or shells behind. Over time sediment builds over the top and hardens into rock

A sedimentary rock feature that forms when muddy deposit dries and shrinks is called_?

Mud crack

What minerals make up sedimentary rock?

Quartz, chert, flint, muscovite, clay, gypsum, halite, feldspar, calcite, dolomite, pyrite

A sedimentary rock feature cause by the action of wind or water on sand is called_?

Ripple marks

What are some types of chemical sedimentary rock?

Rock salt, iron ore, chert, flint, dolomites, limestones

Organic Sedimentary Rock

Sedimentary rock that forms from the remains of plants or animals

Clastic Sedimentary Rock

Sedimentary rock that forms when fragments of preexisting rocks are compacted or cemented together

Chemical Sedimentary Rock

Sedimentary rock that forms when minerals precipitate from a solution or settle from a suspension

Define sorting.

The tendency for currents of air or water to separate sediments according to size

Name the 4 agents that transport sediments.

Water Ice Wind Effects of gravity

How do poorly sorted and well-sorted sediment differ?

Well-sorted The grains are roughly the same size and shape Poorly-sorted The grains are different size and shape

How are newly formed sediments transported to new locations?

Wind water or ice

Coal forms from plant remains that are buried before they decay and are then compacted into matter that is composed mainly of_?

carbon

The process in which minerals precipitate into pore spaces between sediment grains and bind sediment together to form rock is called?

cementation

An example of limestone made up of the shells of tiny, one celled marine organisms that settle to the ocean floor is_?

chalk

The process in which the volume and porosity of a sediment are reduced by the weight and pressure of overlying sediment is called?

compaction

When water evaporates, it leaves behind minerals called_?

evaporites