Igneous rock, or magmatic rock, is one of the three main rock types. Igneous rock is formed by magma or lava cooling and solidifying. In either the mantle or crust of a planet, the magma can be derived from partial melts of existing rocks. The melting is typically caused by one or mor...
Pumice: Frothy, light-weight rock formed from gas-rich lava, pumice is porous and can float on water. Sedimentary Rocks Sedimentary rocks form from the accumulation and compaction of sediments, which can include fragments of other rocks, minerals, and organic material. These rocks often form in...
Intrusive Igneous Rocks: magma pushes into surrounding rock below the Earth’s surface Extrusive Rocks: forms when magma erupts onto the Earth’s surface (lava), cools quickly with very small or no crystals formed http://.windows.ucar.edu/tour/link=/earth/geology/ig_intrusive.html&edu=high&...
Basalt:Basalt is an igneous rock formed from cooled lava. It is relatively resistant to weathering due to its high density and the durability of its minerals. Basalt weathers more quickly than granite because it contains minerals like olivine and pyroxene, which are more susceptible to chemical we...
When molten rock erupts onto the Earth's surface, it cools quickly, freezing the growth of existing minerals and preventing the development of new minerals. Such rapid cooling will typically produce lava rocks with a few small minerals suspended in a groundmass of volcanic glass. Molten rock tha...
These rocks have smaller grain crystals that you can barely see because the lava cools so quickly. They do not have time to form. These types of rocks can form anywhere from a few seconds to a few months. The most common type of extrusive igneous rock is basalt. ...
Igneous rocks are hard and dense and can be formed in two ways: Intrusive (or plutonic) rocks are formed from the cooling and crystallization of magma as it remains inside the Earth’s crust. Continuation of igneous rock types: Extrusive rocks are formed from lava on the surface of the ...
(below ground) igneous features such as sills and dykes. The eruptions from these volcanoes may be a pyroclastic flow rather than a flow of lava. A pyroclastic flow is a superheated mixture of hot steam, ash, rock and dust. A pyroclastic flow can travel down the side of a volcano at ...
The three types of rock are sedimentary, igneous, and metamorphic. Sedimentary is formed from previous rock or once-living organisms. Igneous rock is formed from cooled magma or lava. Metamorphic rock is formed from rocks exposed to high heat and pressure. ...
One volcanic landform formed by lava is a lava dome, which results from thick lava that does not flow easily. As it cools, it forms a mound of rock on top of the volcano. If the lava from a volcanic eruption is thin and flows easily, it will spread over a wider area and form a ...