STRATIGRAPHY QUESTIONS

Stratigraphy Questions

Stratigraphy Questions

Question 1: What information can be extracted from sedimentary rocks that will allow us to interpret environments of depositions?

Sedimentary rock information provides significant information about the history of the environment of Earth. Particle size of the sedimentary rocks provides information about the energy of the medium transported to the minerals depositions. This is explained by the formation of gravel that moves by the swiftly flowing rivers; presence of gravels on barren land highlights the present of water in the past in that region (Fichter, 2008). Layers of sedimentary rocks also enable interpreting the Earth's history, understanding the nature of the nature of the environment of the Earth at the time the sediment was deposited (Fichter, 2008). Strata or beds are most important characteristic feature of sedimentary rocks that enable understanding the occurrence of volcanic eruption and tectonic plates uplift.

Question 2: Sedimentary Rocks Classification

On the basis of formation, sedimentary rocks are classified in two groups. These include clastic and chemical sedimentary rocks. Table presented below shows that classification of sedimentary rocks in each group. When rock form from weathering of rock particles, it is classified as clastic sedimentary rocks; however, classification in chemical rocks is due to precipitation of minerals dissolved in water (Middleton, 2003).

Question 3: Definitions

Denudation

Denudation is a geological process under which loss of soil and rock debris occurs naturally. Denudation is a gradual erosion process combined with weathering and mass wasting effect, which may execute by processes such as tectonic plates uplift and earthquakes (Tucker, 2003).

Textural Maturity

Textural maturity of sedimentary rock represents the sorting of detrital grains, grain-angularity (roundness) of rock sediments, and clay matrix. Textual maturity occurs in four stages (Ghosh, 2005). These include removal of clay particles, arrangement of sand particles fraction, and roundness of grains.

Arkose

Arkose can be defined as a detrital sedimentary rock that forms by the weathering of igneous or metamorphic, and breakdown of granitic rocks. Arkose rock contains a significant proportion of feldspar and quartz along with other detrital minerals and rock segments, such as mica (Tucker, 2003). Grains of arkose are angular in nature.

Pebble

Geologists refer to pebble as clast of sedimentary rock that form (rounded) due to erosion or by the action of water. Pebbles usually have size between 4 to 64mm (Tucker, 2003). They are smaller than cobbles but are significantly larger than granules.

Rediolarian Chert

Rediolarian Chert is a sedimentary rock containing a variety of chert. Chert refers ...