Gabbro, a type of intrusive igneous rock, is formed when magma cools and solidifies inside the crust of the Earth. Because it cools slowly, it is coarsely grained.Know More
Gabbro is the intrusive equivalent to basalt, an extrusive rock formed by molten magma that cools on the Earth's surface. However, unlike extrusive rocks, which cool rapidly when exposed to the atmosphere, intrusive rocks, surrounded by pre-existing rock, push up from within the Earth and cool in a process that can take millions of years. Large deposits of gabbro lie beneath the oceanic crust, where magma cools extremely slowly to form large-grained holocrystalline masses. Gabbro is found in many places on Earth. It is also present on the moon.
The German geologist Christian Leopold von Buch, who studied the volcanic origins of minerals in Italy, named gabbro after a town in Tuscany. Gabbro is dense and dark-colored. Unlike granite, it contains no quartz and little silica. It contains pyroxene, plagioclase, amphibole and olivine. It often contains large but low-grade amounts of gold, silver, platinum, chromium, nickel and cobalt. Its dark appearance precludes its widespread use in construction, but it is often used for paving stones, headstones for graves and kitchen countertops, in which case it is referred to erroneously as "black granite."Learn More
Calcium is very abundant throughout the Earth's crust and can be mined anywhere. Calcium can be obtained from many minerals but is most commonly taken out of limestone, marble, dolomite, gypsum, anhydrite or aragonite.Full Answer >
The Earth's crust is composed of several minerals and elements, including iron, oxygen, silicon, magnesium, sulfur and nickel. Present in smaller amounts are calcium, aluminum and several other elements. The crust is the outermost portion of the Earth, which is comprised of three layers.Full Answer >
Granite and gabbro are igneous rocks formed through the cooling and crystallization of magma in the Earth's crust. They are identified by their specific mineral content and composition.Full Answer >
An upwarped mountain is a mountain formed from force created by heat or magma pushing up directly under the Earth's crust. The force lifts the layers of rock in the Earth's crust above ground level.Full Answer >