why barytes of specific gravity 4.2 is used in place of 4.1 to raise density of drilling fluid?

Question

Answer should be regarding oil exploration

Answer 1

Barite has a high specific gravity because it has the element barium in its molucular structure. I don't know what you me by the phrase "in place of 4.1", because ordinary rocks don't have that high a specific gravity, much less sediments. The high density is needed to prevent a blowout when an oil resevoir is breached that contains hydrocarbons under high pressure.