Much like the Earth, the crust of our Moon, the planets Mars and Venus, and many asteroids are largely made of basalt. In fact, Olympus Mons, the largest volcano in our solar system, is completely formed out of basaltic lava flow.
Basalt is a finely granulated igneous rock, which is usually black or gray in color. Most basalt rocks are primarily composed of the mineral’s pyroxene and feldspar. These rocks are formed due to lava flow. It is a type of rock that is abundantly found in the crust of the Earth, and although now found very commonly on land, ocean floor areas are underlain with basalt that covers a large percentage of the Earth.
At Oceanic Divergent Boundaries
Most of Earth’s basalt is found at the tectonic plate boundaries in the ocean, which forms a global mid-ocean ridge system.
Oceanic hotspots are known to produce large amounts of basalt. The magma flow at any one spot can erupt, and continuous lava flow at such locations can gradually accumulate to become an island.
Continental Volcanic Activity
Basalt, which is formed inland, mostly comes from large vents and fissures which deposit huge amounts of basaltic lava to the Earth’s surface.
Basalt Rock Life Cycle
This is a process that takes place over a period of millions of years. All the basaltic magma that is pushed out of the mantle to the crust due to convection currents is constantly pushed away from the fissures due to new magma flow. Eventually, over a period of many years, the older basalt crust will slowly sink back into the magma, ending its cycle where it began.
Physical Properties of Basalt Rock
Uses of Basalt Rock
Uses During Ancient Times
During the time of the Roman Empire, engineers used basalt for paving roads, and also to create seats in areas of public performances such as stadiums and amphitheaters. Basalt rocks were also widely used in mills for grinding purposes. The Rosetta Stone is also made of basalt.
crushed basalt is used to make the base for roads and pavements, as a part of concrete mixtures, to construct railroads, and as filter stones in drainage projects. The rock is also used in slabs and sheets to create tiles, bricks, and other stone objects for constructing buildings or monuments.
Many farmers and gardeners use basalt rock dust fertilizer, as this is good for promoting the growth of plants, while making it difficult for weeds to spread in flowerbeds and other unwanted areas.
The tensile strength of basalt is very high, much greater than carbon fiber or fiberglass. Therefore, melted composites of the rock are used for manufacturing pipes and rebars that are used in the construction of wind turbine blades. Ophitic basalt is often used in the medical industry for orthopedic purposes.
Basalt is great for insulation purposes and has got very good thermal and friction properties. Therefore, it is often used to replace asbestos to protect people from the toxic effects of asbestos. Apart from insulation, basalt is also used to make worktops, fireplaces, wall panels, etc., and also for interior decoration.
Deepest Part of the Ocean from Basalt
Rosetta Stone Made of Basalt
Basalt in Egypt
In prehistoric times, basalt was already used to make pots, despite the fact that its hardness makes it a difficult stone to work. Basalt vessels, found in the Faiyum and at Merimda-Benisalame, are among the oldest stone vessels ever found in Egypt.
In the Old Kingdom, basalt was occasionally used as material to make sarcophagi and statues, but it was particularly popular for making floors. It is found in various pyramid complexes from the fourth and fifth dynasties (e.g., Khufu, Sahure, Nyuserre, Userkaf). It was very probably quarried in the Faiyum region.
Many of basalt quarries working in Faiyum and Menia governorates.