what is basalt rock

What is basalt rock？Basalt belongs to basic volcanic rocks. It is the main component of the earth and the moon sea ocean crust, the earth crust is an important substance and lunar landing. 

   What is basalt rock？Basalt is a mafic extrusive rock, its chemical composition and the change of the content of SiO2 in the gabbro is similar to that of 45% ~ 52%, the content of K2O+Na2O is the intrusive rocks are slightly higher, CaO, Fe2O3+FeO, MgO content was slightly lower intrusive rocks. The main mineral composition of the base of feldspar and pyroxene, the secondary minerals are olivine, hornblende and biotite, rocks are dark, usually black, sometimes grayish green and dark purple. It is a porphyritic structure. Stomatal structure and almond structure are common.

   What is basalt rock？The volume density of basalt is 2.8 ~ 3.3g/cm3, the compact compression strength is very big,it can be as high as 300MPa, sometimes higher, there is the existence of glass quality and the intensity of the air has been reduced.The basalt has high durability, the joints are many, and the joints are hexagonal. And it has a brittle, and therefore not easy to pick up a large stone, because the structure of the pores and almonds are common, although the surface of a wide range of basalt, but it can be used as a decorative stone. 

   What is basalt rock？Main ingredients of basalt:silicon ,aluminum oxide.iron oxide, magnesium oxide, calcium oxide (as well as a small amount of potassium oxide and sodium oxide),the content of silicon dioxide is the most,it is about forty-five percent to fifty .The common basalt is black, dark brown or dark green. Because of its dense texture, it is more specific than the general granite, limestone, Sha Yan, shale are heavy.

   What is basalt rock？According to their different compositions,basalts can be divided into: tholeiitic basalts, alkali basalt, high alumina basalt.According to its structure, it can be divided into the pores, almond shaped basalt, basalt glass.

According to the filling of different minerals,it can be divided into hypersthene olivine basalt, basalt etc..?