Caves are most commonly formed by the process of erosion. Caves may also be formed by the waves, lava flows or by bacteria that produce acid.Know More
The majority of caves are formed in what is called karst, which is an area made of dolomite or limestone that has underground streams and sinkholes. Rainwater that has combined with carbon dioxide while still in the atmosphere falls and seeps through cracks. With the help of more carbon dioxide, it creates an acid that is weak but capable of eating away at the rocks over time. After millions of years, this acid hollows out areas that eventually join to form a cave.
Caves that form along the ocean shore are called sea caves. These caves are formed by the waves hitting the cliffs and eroding the soft rock over time.
Lava tubes are caves that are formed when a lava flow cools along the outer edges faster than in the middle. This forms a crust around the flow of lava, which hardens and creates a cave.
Certain bacteria feed off of oil deposits and produce a gas which forms a strong acid when it mixes with oxygen. This acid erodes rocks and creates caves that require special equipment including a supply of oxygen to visit.Learn More
Cliffs form through tectonic activity, water movement, weathering, erosion and glacier activity. Earthquakes and landslides also form cliffs. Cliffs tend to form on coasts, in mountainous areas, along rivers or as the walls of canyons.Full Answer >
Streams form when downhill running water creates a channel capable of carrying water. Most streams begin as temporary rivulets that only have water after a rainfall.Full Answer >
Uluru began to form over 550 million years ago when sand, eroding from the Peterman Ranges, built up into thick deposits. Some 50 million years later, these deposits were compressed into sandstone by the weight of a sea that eventually disappeared. Within another 100 million years, geological events caused the sandstone to tilt almost 90 degrees, resulting in Uluru.Full Answer >
Islands form in several ways. The most common events that lead to island formation are volcanic activity and continental drift. Islands also form due to erosion, buildup of sediment and coral that grows enough to penetrate the surface of the water.Full Answer >