Are you ready to rock?
By: Alicia Crespo
What is a rock?
A rock is a solid material made of minerals. Some are formed on the surface of earth and some are formed deep near it's core.
Igneous Rocks
Igneous rocks are formed by being melted and solidified. They are formed either inside or outside a volcano. The two main types are Intrusive and Extrusive. Intrusive rocks form slowly and have large crystals. Extrusive form quickly and have small crystals.
Sedimentary Rocks
Sedimentary rocks are formed by cementing and compacting sediments. They are formed on the Earth's surface. The main types Clastic, Bioclastic, and Crystalline. Clastic are made of different sized particles cemented together. Bioclastic are made of animal or plant remains. Crystalline are formed when materials are left behind after water evaporates.
Metamorphic Rocks
Metamorphic rocks are formed when they are exposed to heat and/or pressure, with no melting. They are formed deep within the Earth, near the core. The two main types are Foliated and Non-foliated. Foliated have an alignment of minerals.
TYPES OF ROCK
Rhyolite
1.) Crystals form quickly. Form outside a volcano.
2.) Texture- Fine; Crystal size-Non-crystalline
3.) Non-vesicular
4.) Density- Low; Color-Lighter; Mineral composition- Felsic
Conglomerate
Organic or Inorganic: Inorganic
Texture: Clastic
Grain Size: Pebbles, Cobbles, and/or boulders embedded in sand, silt and/or clay.
Composition:Mostly quartz, feldspar, and clay minerals.
Comments: Rounded fragments
Slate
Texture: Foliated
Grain Size: Fine
Composition: Mica
Comments: Low-grade metamorphism of shale.
Rock Cycle
The Rock Cycle is a model showing how rocks and sediments change over time.