SOLAR SYSTEM

Detailed explanation-1: -Oceanic crust, extending 5-10 kilometers (3-6 kilometers) beneath the ocean floor, is mostly composed of different types of basalts. Geologists often refer to the rocks of the oceanic crust as “sima.” Sima stands for silicate and magnesium, the most abundant minerals in oceanic crust. (Basalts are a sima rocks.)

Detailed explanation-2: -Oceanic crust is created as magma rises to fill the gap between diverging tectonic plates and is consumed in subduction zones. It is geologically young, with a mean age of 60 Ma, and is thin, averaging 6.5 km in thickness. Oceanic crust consists almost exclusively of extrusive basalt and its intrusive equivalents.

Detailed explanation-3: -THE typical basalt of the ocean floor and mid-ocean ridges seems to be chemically variable, within a somewhat restricted range1–4, but most contain olivine and hypersthene in the CIPW norm, and carry sparse phenocrysts of olivine, more frequently accompanied by plagioclase than by clinopyroxene1–6.

Detailed explanation-4: -Far down beneath accumulated layers of sediment, the floor of the ocean is made of basaltic rock. This rock was formed from molten lava that oozed up from deep within the planet at the boundaries of Earth’s tectonic plates. It is difficult to reach, and mostly unexplored.

Detailed explanation-5: -The oceanic crust, which, on average, is only about six kilometers thick, is primarily made up of the igneous rock basalt. Basalt tends to come from lava that flows smoothly and quietly from a volcanic vent, unlike the viscous lava typical of the violent eruptions of many continental volcanoes.