when igneous rock,such as granite,is put under pressure and heat,deep underground,the mineral crystals are sqweezed into bands,making gneiss.
2006-10-12 13:31:26 · 5 answers · asked by andrew 3 in Science & Mathematics ➔ Earth Sciences & Geology
Metamorphic. Metamorphic rocks are those formed by applying heat and pressure to preexisting rocks.
2006-10-12 13:51:37 · answer #1 · answered by ohmneo 3 · 1⤊ 0⤋
When heat, pressure and time are combined to modify a rock without actually melting it (that point is key) then that rock has been metamorphosed.
Taking a piece (or a mountain) of granite and slowly changing it to gneiss is an example turning an igneous rock (granite) being metamorphosed into gneiss. Gneiss is a metamorphic rock.
2006-10-13 00:00:14 · answer #2 · answered by d 3 · 0⤊ 0⤋
Rock Grain Pressure: Since individual grains often do not exist within a rock formation the rock grain pressure refers to a theoretical fraction of the overburden pressure which is supported by the rock matrix of the formation. Since a rock mass is not homogeneous, pressures will not be exerted equally in all directions as is the case with fluid pressures
2006-10-12 21:02:31 · answer #3 · answered by Zoocar1 2 · 0⤊ 1⤋
Let me see...heat and pressure? Wouldn't that be a metamorphic rock?
2006-10-13 10:33:31 · answer #4 · answered by Amphibolite 7 · 0⤊ 0⤋
A result of high-grade regional metamorphism.
2006-10-13 01:33:53 · answer #5 · answered by Anonymous · 0⤊ 0⤋