what are sedimentary rocks?

Answer 1

sedimentary rocks are the ones like sandstone, or rocks that you'll see that have stripes of different colors through them. They're made over LONG periods of time when different kinds of "sediment" pieces of the eart that settle down into place, like sand, dirt, little pieces of gravel, etc get all.... smooshed together. When you drive on the highway, sometimes you'll see hills beside the road that are all stripey and different colors. This kind of rock is sedimentary.

Hope that made sense, hope it helps!

Answer 2

Every minute of every day, rocks are being worn down by wind and rain. Tiny grains of dirt, sand, mud and clay are worn off and washed into streams, rivers, lakes and oceans. When these tiny bits of sand and dirt settle to the bottom of the water, they are called sediment. Minerals in the water and microscopic, or very tiny sea animals also get mixed in with the dirt and sand to form the sediment. Every day more sediment piles on top of what is already there. After thousands and millions of years we end up with a really deep pile of sediment. The weight and pressure from all the stuff on top turns the sediment on the bottom into sedimentary rock!

Answer 3

sediment

mineral or organic particles that are deposited by the action of wind, water, or glacial ice. These sediments can eventually form sedimentary rocks

Classification of Sediments

Sediments are commonly subdivided into three major groups–mechanical, chemical, and organic.

Mechanical, or clastic, sediments are derived from the erosion of earlier formed rocks on the earth's surface or in the oceans. These are then carried by streams, winds, or glaciers to the site where they are deposited. Streams deposit sediment in floodplains or carry these particles to the ocean, where they may be deposited as a delta. Ocean sediments, especially in the form of turbidites, are usually deposited at the foot of continental slopes (see oceans). Glaciers carry sediment frozen within the mass of the ice and are capable of carrying even huge boulders (erratics).

Chemical sediments are formed by chemical reactions in seawater that result in the precipitation of minute mineral crystals, which settle to the floor of the sea and ultimately form a more or less chemically pure layer of sediment. For example, evaporation in shallow basins results in a sequence of evaporite sediments, which include gypsum and rock salt.

Organic sediments are formed as a result of plant or animal actions; for example, peat and coal form by the incomplete decay of vegetation and its later compaction. Deep-ocean sediment known as pelagic ooze consists largely of the remains of microscope organisms (mostly foraminifera and diatoms) from the overlying waters as well as minor amounts of windblown volcanic and continental dust. Limestones are commonly formed by the aggregation of calcite shells of animals.

Formation of Sedimentary Rock

Sediments form sedimentary rock by compaction and cementation of the particles. Thus, coarse sediments become conglomerates; sands become sandstone; and muds become shale. Sedimentary rocks make up only about 5% of all rocks of the earth's crust, yet they cover 75% of the land area in a veneer that averages 2.26 km (1.4 mi) in thickness, ranging from 0 to 12.9 km (0—8 mi).

Answer 4

go 2 google and search for it.....use ur book too