Sentence examples for layers of limestone from inspiring English sources

Other shajiang tu soils develop impervious layers of limestone hardpan.

When prospecting for deep systems, cavers start in mountains with thick layers of limestone deposited by ancient seas.

In warm (tropical to subtropical) shallow waters, carbonates may collect more gradually to form continuous layers of limestone.

It contains millions of them, beautifully preserved in layers of limestone that are interspersed with volcanic ash.

Most geologists believe that the Black Hills caves were formed about 50 million years ago by underground water dissolving layers of limestone.

There, streams cut their way through layers of limestone, leaving extensive caverns beneath the surface and steep, rocky bluffs rising high above the valleys.

Above this a layer of limestone rubbish thrown out of pits, and then came drifted sand to present surface.

Below the tar sands, there's a thick layer of limestone, the remains of an ancient ocean that once covered Alberta.

The specimen was discovered inside a layer of limestone in which the fossils of long-extinct animals, including mammoths, rhinos and giraffes, had already been identified.

These wells reach more than 7000 feet deep below the surface into the Arbuckle formation, a roughly 500 million year old layer of limestone.

It was in the central part of the state, in the rolling hills between Lexington and Louisville — where a layer of limestone filters the iron from the water, making it ideal for bourbon making — that Scotch-Irish distillers settled in the early 1800s.