Rocks specific gravity

In oil bearing formations, the presence of polar chemical functions of asphaltenes probably makes the rock wettable to hydrocarbons and limits their production. It also happens that during production, asphaltenes precipitate, blocking the tubing. The asphaltenes are partly responsible for the high viscosity and specific gravity of heavy crudes, leading to transport problems. 

Strontium Sulfate. Strontium sulfate, SrSO, occurs as celestite deposits in beds or veins in sediments or sedimentary rocks. Celestite has a specific gravity of ca 3.97, a Mohs hardness of 3.0—3.5, and is colodess-to-yeUow and often pale blue. Strontium sulfate forms colorless or white rhombic crystals with a specific gravity of 3.96 and an index of refraction of 1.622—1.631. It decomposes at 1580°C and has a solubiUty of 0.0113 g per 100 mL of water at 0°C. 

The average specific gravity of minerals in the earth s crust is taken to be 2.7. The average specific gravity of saltwater is taken to be 1.07. If the average sedimentary rock porosity is assumed to be 10%, then the total theoretical maximum overburden pressure gradient (lb/fp)/ft becomes... 

Anorthite was named by Rose in 1823 from the Greek meaning oblique, referring to its triclinie crystallization. The physical properties are essentially the same us tor albite. except that the specific gravity of anorthite is somewhat greater. 2.74-2.76. Anorthite is characteristic of the basic igneous rocks such as gahbro and basalt. Anorthite is found in the lavas of Vesuvius and Monte Somma. Italy in Finland Japan and in the United Stales, in Sussex County. New Jersey. 

PEROVSKITE. The mineral perovskite is calcium titanate, essentially CaTiCL, with rare earths, principally cerium, proxying for Ca, as do both ferrous iron and sodium, and with colunibiuni substituting for titanium, ll crystallizes in die orthorhombic system, but witli pseudo-isometric character fracture subconchoidal to uneven brittle hardness, 5.5 specific gravity. 4 luster, adamantine color, various shades of yellow to reddish-brown or nearly black transparent to opaque. It is found associated with chlorite or serpentine rocks occurring in the Urals, Baden, Switzerland, and Italy, It was named for Von Perovski. 

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