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Basalts are igneous rocks formed from flowing lava that are cooled rapidly. Basalts have a refined grain appearance that is caused by the cooling process that they undergo. This is a greyish black rock that can also be found on Earth, Mars, Venus, the Moon and the asteroid Vesta. 

There are three similar environments where this volcanic rock is formed; the oceanic divergent boundaries, hotspots and mantle plumes beneath the continents and the oceanic hotspots.

· Oceanic Divergent Boundaries. Most of the Earth’s basalts are produced at the mid-ocean ridge system, on the divergent plate boundaries of the system. The convection currents in this area deliver the hot rock from the mantle deep. The hot rock will melt when the conflicting boundary pulls apart and will then erupt to the sea floor. The fissure eruptions can produce pillow basalts.

· Oceanic Hotspots. The production of this volcanic rock begins when the ocean floor erupts. When the hotspot is sustained, there will be repeated eruptions that will make the volcanic cone become larger and larger, and will become an island. The Hawaiian Islands were built from the eruptions of basalts on the sea floor.

· Hotspots and Plume Below the Continents. This third environment is a continental environment wherein the plume or the hotspot will deliver a large amount of basaltic lava through the crust of the continents and the surface of the Earth. The eruptions can be caused by wither fissures or vents. They produce the largest flow of basalts on the Earth. The eruptions may occur repeatedly creating layers and layers of basalts in a vertical stack.

Basalts are seen in a lot of locations across the world, just like in Hawaii. The land’s extensive flood basalts are in the Columbia River Flood basalts in Oregon, Idaho and Washington. Anther location in America is the Lake Superior region’s Kaweenawan Lavas. In other continents, basalts can also be found in the Deccan Traps of India, the Emeishan Traps of China, the Karroo Basalts of South Africa, the Siberian Traps of Russia and the Etendeka Basalts of Namibia. Trap, as seen in the names of a lot of Basalt locations, is the outcrop profile of the layered deposits of Basalts.

Basalt can also be found in other planets, like on the Moon. As a matter of fact, much of the Moon is underlain by flows of basaltic lava and the flood basalts, known as the Lunar Maria. Olympus Mars, the shield volcano of Mars, is formed by the flows of basaltic lava. Olympus Mars is the Mars’ highest mountain and the largest in the solar system.

Basalt is not just a fascinating rock. It has a lot of purposes and functions. The crushed basalts are used as an aggregate in the construction, used as a road base, a concrete aggregate, a railroad ballast, asphalt pavement aggregate and filter stone for the drain fields. Basalts are cut up as dimension stones. Thin basalt slabs are sliced and polished to be used as building veneers, monuments and floor tiles.

Basalt stone is used for a lot of applications, like outdoor and indoor flooring. It is best that the appropriate basalt materials are used to ensure the durability and the quality of the finished look. Correctly applied, the material will provide a longer life, even the life of the structure if used as a construction material. 

Basalt stones that are weather resistant and durable is perfect for the outdoor use. When it comes to indoor uses, the strict guidelines for selecting the right stone are lessened.

Additional Resources

Aplite   Basalt Uses   Biotite

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