Earth’s Crust, Research Paper Example

The continental crust is the layer of sedimentary, granitic, and metamorphic rocks which figure the continents and areas of shallow seabed near to their shores, well-known as continental shelves (ScienceDaily, 2010).

Earth’s continental crust is composed of the following elements, Silicon, Oxygen, Aluminum, Calcium, Sodium, Magnesium, Potassium, and iron. Between these elements, the most notable are oxygen and silicon; oxygen covers approximately 46.5 percent while Silicon covers approximately 28 percent. They are noteworthy because they make up Earth’s crust, which includes silicate minerals such as micas, quartz, and olivine among others (Windows to the Universe, 2010).

Physical properties that identify common minerals include: Hardness, minerals are identified by their hardness on the Mohs scale of hardness which range from #1 (softest) to #10 (hardest). Specific Gravity, this is the relative weight of a mineral in comparison with volume of water which has equal weight. Magnetism, certain minerals show magnetism or a pull to a magnet, and few will show this property only when heated.

Crystal Form, a mineral’s crystals structure into one of six mineral crystal systems. This crystal form shows the structure of the molecules and creation environment of the mineral. Color, the color of specimen as seen with naked eyes under normal lighting condition helps one to identify the mineral, while Mineral Such as gold will only appear like one color while other have different colors. Crystal form is the least because it makes it difficult to distinguish the minerals. For example, most minerals are compounds, meaning they have two or more elements, the major components of almost every rock are silicate and oxygen which makes it difficult to identify small minerals.

References

ScienceDaily (2010). Continental crust. Retrieved Oct. 11, 2010, from, http://www.sciencedaily.com/articles/c/continental_crust.htm

Windows to the Universe (2010). Elements in the Earth’s Crust. Retrieved Oct. 11, 2010, from, http://www.windows2universe.org/earth/geology/crust_elements.html