Mysterious tunnels in desert rocks may be the work of unknown microbes, hinting at a hidden world inside marble and limestone ...

Foote's mineral specimens are very valuable. Formation - A formation is a set of rock layers that consists dominantly of a certain rock type or combination of types. Fossiliferous Limestone - ...

In the desert areas of Namibia, Oman, and Saudi Arabia, research work has revealed unusual structures that are probably due ...

The discovery has sparked interest among scientists studying endolithic microorganisms, unknown life forms inside rocks.

Rockport State Recreation Area is known to have exposed fossils from the Devonian period – more than 400 million years ago.

Where limestone lies on top of an impermeable rock along a valley there can be several springs formed along the intersection of the two rocks. This is a spring line. The ice sheet which covered ...

John Wesley Powell A professor of geology at Illinois Wesleyan ... This layer of rock, known as the Redwall Limestone, forms a sheer cliff 500 ft high or more in most areas.

Huge reef systems flourished in the clear, tropical seas—evident today in the many limestone rock formations that date to this period. Previous reef-builders such as bryozoans were joined by ...

hard rock, making the underground formation extremely "tight." Tight gas can also be trapped in sandstone or limestone formations that are atypically impermeable or nonporous, also known as tight ...

Chalk, limestone, shale, and sandstone are all examples of sedimentary rocks. All these different sedimentary rocks are formed from the broken remains of other rocks that become joined together.