How do you know if a sedimentary rock is clastic or organic?

Clastic sedimentary rocks are made of sediments. The sediments differ in size. Chemical sedimentary rocks are made of minerals that precipitate from saline water. Organic sedimentary rocks are made from the bodies of organisms.

How can you tell if a rock is organic or clastic?

Clastic rocks are classified by grain shape, grain size, and sorting. Chemical sedimentary rocks are precipitated from water saturated with dissolved minerals. Chemical rocks are classified mainly by the composition of minerals in the rock.

How can you determine if a sedimentary rock is clastic or non-clastic?

If non-clastic rocks are fine-grained enough, they too can be called aphanitic. Clastic sedimentary rocks are subdivided on the basis of grain size. Secondary characteristics used to further distinguish clastic rocks are sorting, grain shape, and grain composition.

Is sedimentary rock clastic chemical or organic?

Clastic sedimentary layers are formed by erosion and the accumulation of small broken bits of rock. Chemical sedimentary layers and organic sedimentary layers are not the result of erosion. Chemical sedimentary layers are the accumulation of precipitates of organic material.

What makes a sedimentary rock clastic?

Clastic sedimentary rocks are rocks composed predominantly of broken pieces or clasts of older weathered and eroded rocks. Clastic sediments or sedimentary rocks are classified based on grain size, clast and cementing material (matrix) composition, and texture.

What are organic sediments?

Organic sedimentary rocks are those containing large quantities of organic molecules. Organic molecules contain carbon, but in this context we are referring specifically to molecules with carbon-hydrogen bonds, such as materials from the soft tissues of plants and animals.

What does clastic sedimentary rock look like?

Clastic sedimentary rocks may have particles ranging in size from microscopic clay to huge boulders. Their names are based on their clast or grain size. The smallest grains are called clay, then silt, then sand. Grains larger than 2 millimeters are called pebbles.

What are the characteristics clastic rocks?

Clastic sedimentary rocks are named according to the characteristics of clasts (rock and mineral fragments) that comprise them. These characteristics include grain size, shape, and sorting. The different types of clastic sedimentary rocks are summarized in Figure 9.5.

What is clastic texture?

Clastic texture: grains or clasts do not interlock but rather are piled together and cemented. Boundaries of individual grains may be another grain, cement or empty pore space. Overall rock is generally porous and not very dense.

Which rock is an example of a clastic sedimentary rock?

Clastic sedimentary rocks form from the accumulation and lithification of mechanical weathering debris. Examples include: breccia, conglomerate, sandstone, siltstone, and shale. … Examples include: chert, some dolomites, flint, iron ore, limestones, and rock salt.

What are some examples of organic sedimentary rocks?

Organic sedimentary rocks form from the action of organisms. Examples include fossiliferous limestone and coal. Fossiliferous limestone and coal are two examples of organically-formed sedimentary rocks. This fossiliferous limestone (left) is from Giles County, and was formed from the shells of many aquatic organisms.

How clastic sedimentary rock differs from chemical and organic sedimentary rock?

Clastic sedimentary rocks are made of sediments. The sediments differ in size. Chemical sedimentary rocks are made of minerals that precipitate from saline water. Organic sedimentary rocks are made from the bodies of organisms.

What are some characteristics organic sedimentary rocks?

Organic sedimentary rocks form from the accumulation and lithification of organic debris, such as leaves, roots, and other plant or animal material. Rocks that were once swampy sediments or peat beds contain carbon and are black, soft, and fossiliferous.