260 likes | 416 Views
Plate movement, Erosion, and all. Earth Processes give us…. Rocks!. Rocks!. Made up of a mineral or a mixture of minerals May also contain sediments and fossil remains of plants and animals They are the result of natural forces at work on our planet
E N D
Plate movement, Erosion, and all Earth Processes give us…
Rocks! • Made up of a mineral or a mixture of minerals • May also contain sediments and fossil remains of plants and animals • They are the result of natural forces at work on our planet • The study of rocks is called petrology
Rock made up of one type of mineral Quartzite – made up of the mineral quartz The most common mineral on earth is quartz.
ROCKS are the records to our planet’s past! • They indicate where rivers have flowed • Where huge inland seas were located • What organisms lived in those seas • Where glaciers covered land
Basic Rock Types • All rocks fall into one of 3 basic groups: 1.Igneous 2. Sedimentary 3. Metamorphic
Igneous Rocks Igneous means “fire” Form from the cooling of liquid rock (magma) that came up from deep within the earth. It is the melting and solidification of metamorphic rocks! Igneous rock is the most common material of the earth’s crust!
Igneous Rocks: • Often hidden by sedimentary rock • Can be intrusive or extrusive igneous rock • If recrystallization and solidification occurred below the earth’s surface (such as the formation of granite), than the rock is intrusive • If the rock formed on the earth’s surface from cooling of volcanic lava (such as obsidian and basalt), than the rock is extrusive
Igneous Rocks: • If rock formed from a slow cooling, the rock will contain coarse-textured minerals (Example = granite) • If rock formed from a fast cooling, the rock will contain fine-textured minerals (Example = basalt) • If rock contains a high amount of silica, it will be light in color and weight, and be known as acidic • If rock contains high amounts of iron and magnesium, it will be dark-colored and heavy, and be known as basic
Basalt Most common extrusive and basic igneous rock
Granite Most abundant of all igneous rocks
Sedimentary Rocks • Form from the burial and cementing of layers of sediment broken off of other rock types and deposited in water. Weathering and erosion can be caused by wind, waves, gravity, or water. Rivers carry sediment for long distances.
Sediment: • Sand • Gravel • Mud • Clay
Name of Particle Size Range Loose Sediment Consolidated Rock Boulder >256mm Gravel Conglomerate or Breccia (depends on rounding) Cobble 64 – 256 mm Gravel Pebble 2 - 64mm Gravel Sand 1/16 –2mm Sand Sandstone Silt 1/256 - 1/16mm Silt Siltstone Clay <1/256mm Clay Claystone, mudstone, and shale
Compaction from the weight of accumulating sediment results in layers that become hardened and turn to sedimentary rocks!
Shale Clastic (clay)
Conglomerate Clastic (rounded pebbles)
Metamorphic Rocks • Form from pressure and extreme temperatures changing the chemistry of igneous and sedimentary rocks that got buried into the earth over time.
Metamorphosis • Complete change of character, appearance, or condition. • Involves heat, pressure, and chemical action • Process can occur more than once • Results in the recrystallization of original rock (sedimentary or igneous) and a different mineral composition
Rock Cycle is a sequence of processes or events involving the formation, alteration, destruction, and reformation of rocks
The Importance of Rocks and Minerals Name Type of Rock Use Basalt Igneous Used in road building materials Calcite Mineral Used in cements and mortars and the production of lime Granite Igneous Used for buildings, monuments, and tombstones Marble Metamorphic Used in building, floors, tile in bathrooms Obsidian Igneous Used in making arrowheads and knives Pumice Igneous Used in scouring, scrubbing, and polishing materials Quartz Mineral Used in making glass, electrical components, and optical lenses Sanstone Sedimentary Used in the building industry for houses Slate Metamorphic Used for roofs, chalkboards, and patio walks
Landforms • Part or area of the Earth’s surface that has a distinctive shape or topography
Weathering is a series of natural processes, both physical and chemical, that act to change exposed rock into mineral and rock particles and chemical compounds in solution.