Geology Rocks and Stuff
Table of Contents! Rocks/Minerals! Igneous Rocks! Sedimentary Rocks! Metamorphic Rocks! End! References
Rocks/Minerals
Rocks and Minerals I think we all know what rocks are. And we might have heard of minerals. There are different types of minerals. Vitamin minerals, such as iron and zinc that you would have in your daily multivitamin, and the iron and zinc that come out of the ground. The mineral sands and other minerals like that. Minerals often can be on rocks. My research website didn't differentiate between rocks and minerals, so I put them together in this section.
Common Rocks Limestone,! Granite,! Basalt,! Obsidian,! Quartz,! Sandstone, and,! Pumice.
Less well-known Rocks/Minerals Aquamarine,! Piemontite,! Siltstone,! Shungite,! Pryoxenite,! Chert! Metachert,! Shale,! Gypsum,! Serpentinite,! Slate,! Phylite,! Schist,! Quartzite,! Blue schist,! Soapstone,! Eclogite,! Scoria,! Tuff,! Pillow Lava,! Peridotite,! Gabbro,! Felsite, and,! Rhyolite.
Igneous Rocks Igneous rocks are born of fire. They are solidified and crystallized lava or magma. We think molten metal at the same time as we think molten rock. This leads us to think that molten rock is a liquid. Geologists and other Scientists believe this is not a true fact. They have been led to believe that molten rock is a mush, carrying lots of bits of crystal and rock. This mush solidifies or crystallizes and we get our igneous rocks. Igneous rocks can get confusing though, because the lava can pick up other rocks along the way and melt them, and they solidify with the lava, making a igneous cross metamorphic or igneous cross sedimentary rock.
Igneous Rocks There are three types of igneous rocks, and they can be told apart in different ways. The first one is extrusive. Extrusive rocks cool 'quickly'. They can take anywhere from seconds to months to solidify. Extrusive rocks have an Aphanitic texture and have either invisible or tiny grains. The next type is intrusive. Intrusive rocks can take thousands of years to solidify. The last type is plutonic. Plutonic rocks can take millions of years to solidify. Plutonic rocks excite geologists because they solidify underground from magma, not lava. Intrusive and Plutonic rocks have a Phaneritic Texture, meaning they have grains you can actually see. Intrusive rocks have medium sized grains, and Plutonic Rocks can have grains anywhere from the size of a pebble, to a meter wide.
Igneous Rocks There are many types of igneous rocks. Some that I know how they were made are obsidian, an extrusive rock that cooled quickly, and the grains are so small that it looks like a black piece of glass. Pumice and Scoria are full of volcanic gases, so they float in water, Tuff is a strange rock. It is classified as igneous but it is actually a sedimentary rock. It is volcanic ash from the volcano that has gone up into the sky, and has come down and been caught in the sediment, and is a sedimentary rock, and pillow lava is a big, puffy rock that has been extruded underwater. Other rocks include Basalt, Quartz, Granite, Peridotite, Gabbro, Felsite, and Rhyolite.
Quartz Granite Pillow Lava Obsidian
Sedimentary Rocks Sedimentary rocks are made of sediment, often found at the sea or river floor. They are composed of mud, sand, gravel, clay and quartz. However mud is a type of clay and sand comes from quartz. All this stuff gets caught up in the sea floor and becomes sediment. The sediment stays together over a period of time, and undergoes a cementing process. After the cementing process, you are left with a sedimentary rock. Unlike igneous rocks, that are born of fire, sedimentary rocks are made at a 'low' heat, 100 C. The sandy sediment becomes sandstone and the more clay dominated sediment becomes shale.
Sedimentary Rocks Some rocks are classified as others, when they are actually sedimentary. Meet Tuff. A Sedimentary rock whose classification is igneous because it is volcanic ash in sediment. It made it into the sediment and underwent the sedimentary rock type's creation process, but was called igneous, in the end.! There is also organic sedimentary rocks that are created when plankton die and float down to the sea floor, and get caught in the sediment. Once this sediment has undergone the sedimentary process, it either becomes limestone or shale.
Sedimentary Rocks Sedimentary rocks can be found inland because, over time, the sea level has dropped, but it left the rocks where they were. Those rocks are still there, and we can find them today.! If Sedimentary rocks don't emerge from underground, they can sometimes under go a process like metamorphism. This process is called Diagensis. Fluids from the sea above can get into them and change their chemistry, however, this does not happen under conditions harsh enough for it to be called metamorphism. This is sometimes how petroleum is formed.
Limestone Shale Limestone Chert
Metamorphic Rocks Metamorphic Rocks are Modified Sedimentary and Igneous Rocks. When rocks get caught underground, they can undergo a more intense version of Diagensis, which is nowhere near as intense as Metamorphism. When rocks get caught underground, there are some hardcore conditions. Intense heat and pressure go hard at the rock, and can get so intense that it can drain all of the fluid out of the rock, warp and change the shape, and change it's chemistry.
Metamorphic Rocks Sometimes Metamorphism is so intense that the rocks get so warped that they look like taffy. These rocks are known as migmatite. Even harsher conditions can turn the rock into something that looks like plutonic granite. Geologists enjoy finding these rocks and looking at them because they can tell us of events that have happened underground, such as tectonic plate collisions.
Metamorphic Rocks Sometimes metamorphic rocks can be a mixture of sedimentary and igneous rocks. Local, or contact, metamorphism is when there are layers of sedimentary rocks, known as a sedimentary strata, is near a volcano or anything else to do with igneous rocks. What happens is the hot magma leaks out of the volcano, and gets into the sedimentary strata. The sedimentary rocks can then be baked into hornfels, or a cousin rock with coarser grains, called a granofel, geologists also like finding these. Magma can rip rocks off of walls and turn them into cool minerals, too.! Humans use contact metamorphism in our lives too. Lava flows on the surface and coal fires underground can have the same affect as baking bricks at the brickworks.
Metamorphic Rocks The Sedimentary to Metamorphic Process When Sedimentary rocks undergo Metamorphism, they turn into a wide range of rocks. First they turn into slate, then Phyllite, then a mica-rich slate. The mineral quartz doesn't undergo metamorphism, it just becomes more strongly cemented. Sandstone turns to Quartzite. Mudstones - mixtures of clay and sand, either become schists or gneisses. Limestone recrystallises and becomes Marble.
Metamorphic Rocks The Igneous to Metamorphic Process Igneous rocks can turn into various types of rocks at various stages of their metamorphism. Common transformations include Serpentinite, blueschist, and Soapstone. Rarer transformations include eclogite.
Marble Quartzite Phyllite Hornfels
Thanks for Watching and Listening I Hope you enjoyed
References Information References Page/Book Name Author Publisher Date Slide/s information Used URL About Igneous Rocks Andrew Alden About.com 2013 10-13 (Igneous Rocks) http:// geology.about.com /cs/basics_roxmin/ a/aa011804a.htm About Sedimentary Rocks Andrew Alden About.com 2013 14-17 (Sedimentary Rocks) http:// geology.about.com /cs/basics_roxmin/ a/aa011804b.htm About Metamorphic Rocks Andrew Alden About.com 2013 18-23 (Metamorphic Rocks) http:// geology.about.com /cs/basics_roxmin/ a/aa011804c.htm Stay Up-To-Date with Geology Andrew Alden About.com 10 June 2013-29 July 2013 7-23 (Rocks & Minerals, Igneous, Sedimentary, Metamorphic Rocks) http:// geology.about.com /gi/pages/stay.htm
References Page/Book Name Pillow lava - Google Search Obsidian - Google Search Shale - Google Search Chert - Google Search Marble - Google Search Picture References Author Publisher Date 6:42 PM July 30 2013 6:44 PM July 30 2013 3:00 PM July 31 2013 3:02 PM July 31 2013 5:33 PM July 31 2013 Slide/s information Used URL 12 (Igneous Rocks) images.google.com 12 (Igneous Rocks) Images.google.com 17 (Sedimentary Rocks) 17 (Sedimentary Rocks) 23 (Metamorphic Rocks) images.google.com images.google.com images.google.com Hornfels Quartzite Phyllite - Google Search 5:05 PM August 6 2014 23 (Metamorphic Rocks) Images.google.com Self - Taken - - 30 July 2013 1, 2, 6, 8, 13, 17, 24. - Beam Me There Locomotive Labs Apple App Store 10 December 2012 1, 2, 6, 8, 13, 17, 24. App Store Edited by