400 likes | 514 Views
Range of potential total destruction. Group Question (5) What impacts would a VEI 8 eruption of Yellowstone have on the citizens of Florida?. Santorini circa 1650 BC, VEI 6. http://www.santorini.net/caldera.html. EARTH MATERIALS.
E N D
Group Question (5) What impacts would a VEI 8 eruption of Yellowstone have on the citizens of Florida?
Santorini circa 1650 BC, VEI 6 http://www.santorini.net/caldera.html
Mineral: naturally occurring inorganic solid with a defined chemical composition and specific crystalline structure.
Native elements - containing a single element (ex. Gold - Au, Graphite - C) • Oxides - O2- (ex. Hematite - Fe2O3) • Hydroxides - containing OH- (ex. Brucite - Mg[OH]2) • Halides - containing F-, Cl-, Br-or I- (ex. Halite - NaCl) • Carbonates - containing CO32- (ex. Calcite - CaCo3) • Phosphates - containing PO43- (ex. Apatite - Ca5[PO4]3F) • Sulfates - containing SO42- (ex. Gypsum - CaSO4.2H2O) • Sulfides - containing S- (ex. Pyrite - FeS2) • Silicates - containing SiO4-4 (ex. Olivine - Mg2SiO4)
Polymorphs: Some groups of minerals share a common chemical composition but differ in terms of crystalline structure. Polymorphs like graphite and diamond (both composed of carbon) illustrate the significance of crystalline structure to physical properties: graphite (a component of common pencil lead) is soft and opaque black while diamond is very hard and a beautiful gem.
PRS • Which of the following are mineral polymorphs? • Ice (H2O) and water (H2O) • Quartz (SiO2) and Olivine (MgSiO4) • Diamond (C) and synthetic Diamond (C) • Calcite (CaCO3) and Aragonite (CaCO3) • Gypsum (CaSO4. 2H2O) and Anhydrite (CaSO4)
Weathering fast | slow Silicate Minerals
PRS SiO2 an example of a(n) A. Element B. Compound C. Mineral D. Rock
PRS The most common element in the earth’s crust is A. Silicon B. Iron C. Aluminum D. Calcium E. Oxygen
Rocks: assemblages of minerals Igneous – crystallize from magma Sedimentary – form from sediments Metamorphic – change form with heat/pressure
Volcanic Glass – magma cools instantly, no crystals Volcanic Rocks – magma cools rapidly at earth’s surface, small crystals Plutonic Rocks – magma cools slowly at depth, large crystals
Mineral composition Felsic Intermediate Mafic
Felsic Intermediate Mafic Coarse Fine
PRS • What rock can have the same mineral composition as a Basalt? • Rhyolite • Granite • Diorite • Andesite • Gabbro
PRS • Which rock type formed at depth within the crust? • Rhyolite • Basalt • Obsidian • Gabbro • Andesite
Weathering Reaction of minerals in rocks to surface conditions Physical – break into small pieces Chemical – react with water, air, organisms Yields: pieces of resistant minerals -- e.g. Quartz clay minerals formed in soil -- Clay dissolved chemicals -- Ca, Fe
Sedimentary Rocks Erosion Transport Deposition Lithification Clastic Sedimentary Rx – from broken pieces Chemical Sedimentary RX – from dissolved stuff Biochemical Sedimentary Rx – from dissolved stuff
Clastic Sedimentary Rocks – pieces of mins (quartz, feldspars, mica, etc.) & clay gravel conglomerate sands sandstone silt siltstone clay shale, mudstone Sizes sorted by transportation
Chemical Sedimentary Rocks Evaporites – Halite, Gypsum Biochemical Sedimentary Rocks Limestone - Calcite Chalk - Calcite Chert - Quartz
Group PRS In which group of sedimentary rocks do the weathering products of most felsic (rhyolitic) rocks end up? A. Clastic B. Chemical C. Biochemical
Metamorphic Rocks – heat and pressure alters other rx Heat and pressure can come from burial or contact – cause minerals to grow, recrystallize, or change into new mineral. Name of MM rock depends on texture and minerals in it. Minerals depend on protolith and amount of temp & press Contact MM – due to igneous contact Regional MM – burial Foliation – parallel alignment of minerals due to pressure- not all minerals will do this (mostly micas, feldspars do)
MM Rocks include Marble – MM limestone Slate – MM shale Quartzite – MM sandstone Schist – usually can’t tell protolith
You have found a rock. It appears to be composed of Quartz, Potassium Feldspar, and a little mica. The minerals have planar irregular boundaries that appear to interlock with one another like pieces of a jigsaw puzzle. There is no obvious alignment of any minerals. What is the rock? A. Igneous B. Sedimentary C. Metamorphic
May form from basaltic magma Form at the earth’s surface Have texture Made of small grains Granite is an example Form as a result of melting May form from rhyolitic magma May form in presence of water Exposed at surface only after erosion Contains minerals Classified based on density of minerals Dark colored have low silica content Contains visible grains both volcanic both volcanic plutonic both/neither both volcanic plutonic both neither both plutonic