天然における硫黄の分布

抄録

Sulfur (S) is an element of 15th largely existed in earth's crust, 10th in universe, and 7th in human body. S circulates the environmental sphere in various chemical forms, but SO₂ in atmosphere is largely responsible by human burning of S contained fuels and minerals. Underground resources of S and production type of S differ country by country. S content in crude oil varies ranging from less than 0.1% to more than 5% in every oilfield. Large S content unexpected from biological source theory of oil origin might be explained by that melted mineral origin elementary S in underground has met and dissolved into highly aromatic or naphthenic fractions of crude oil and secondarily converted to S compounds. Though supply of S as fertilizer to fields has been decreased, but SO₂ has played an important role of natural supply of S to the earth, especially in highly populated metropolitan areas.