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Why are sandstone and limestone often good petroleum reservoir rocks?

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Multiple large offshore petroleum oil rigs with cranes and equipment stand in the ocean, connected by walkways above the water. — petroleum Liquid petroleum (crude oil)—which is refined into gasoline, diesel, heating fuels, asphalt, plastics, and other useful chemical compounds—is often extracted from the ground using a series of drills and pumps.

Sandstone and limestone are effective petroleum reservoir rocks primarily because they possess high porosity and permeability.12

Porosity refers to the volume of pore spaces within the rock, which allows it to store significant quantities of migrating oil and natural gas. Permeability describes the interconnectedness of these pores, which is essential for the fluid to flow through the rock and be extracted efficiently when a reservoir is penetrated by a drill hole.12

These properties can be primary, resulting from the original size, shape, and packing of sediment grains during deposition, or secondary, induced by post-depositional processes such as fracturing, weathering, or chemical dissolution. While sandstones are common clastic reservoirs, limestones and dolomites serve as important carbonate reservoirs. In both cases, the ability of the rock to hold and transmit fluids is the defining characteristic that makes it a suitable host for petroleum accumulation.12