GEO 101N 1st Edition Lecture 12Outline of Last Lecture I. Mineral CharacteristicsII. Mineral ClassesIII. Common Rock-forming MineralsIV. RocksV.Rock ClassificationVI. Physical CharacteristicsOutline of Current Lecture VII. Libby Montana-AsbestosVIII. Asbestos MineralsIX. Ca-Na AmphibolesX. Volcanos and MagmaXI. Rocksa. Igneousb. Sedimentaryc. MetamorphicXII. Geothermal GradientXIII. Heat MovementCurrent LectureIV. Libby Montana-Asbestosa. 1924-1990 had a mine, “Zonolite Mine”; mining unltra mafic (high in Fe & Mg) igneous plutonb. Primary product = vermiculite mica-resistant to fire (has a high melting point)-lots of air pockets make it a good insulator-when heated to 1100ᵒC the water in it vaporized and opens the mica structure (metamorphism)-“Zonolite” attic insulation made from the vermiculite mined herec. Amphibole Minerals: another product of metamorphism was mixed in with the vermiculite =asbestiform-small lightweight fibers are easily airborne-health hazards have been recognized since the 1970’sd. Asbestos contaminated everything in Libbye. Waste products were in the air & used in the town for all sorts of thingsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.f. The target mineral in Libby was vermiculite the primary use was attic insulationV. Asbestos Minerals-based on the shapea. Serpentine group: chrysotile; crocidolite; amorite b. Amphibole group: tremolite; anthophyllite; actinolitec. Asbestos is still mined in some places in the worldd. Fire resistant properties make it valuablee. Good insulator; used in brakes, ceiling insulation etc. VI. Ca-Na Amphiboles a. Asbestos from Libby; less commonb. Not intentionally minedVII. Volcanos and magmaa. volcano: a vent at which melt from inside the Earth spews to the surfaceb. lava: melt that reaches the surface; flow is a syrupy yellow melt streamc. magma: underground melt that pushes its way “intrudes” in preexisting rock (called wallrock), here in accumulates into magma chambersVIII. Rock Classificationa. igneous: formed by the freezing (solidification) of molten rockb. extrusive igneous rock: solidifies above ground; includes both solid lava flows, formed when streams or mounds freeze on the surface and pyroclastic debris-includes volcanic ash-fine particles of glass formed from lava freezing in the airc. intrusive igneous rock: when magma solidifies underground; there is a larger volume of intrusive “on” Earth that extrusived. sedimentary: cementing together of fragments (grains) off existing rocks or by the precipitation of mineral crystals out of watere. metamorphic: form from preexisting rocks change character in response to change in pressure and/or temperature conditionsIV. Geothermal Gradienta. Geothermal gradient: the rate of increasing temperature with respect to increasing depth in the Earth's interior (in-out or out-in) b. Out (Surface) to in (center of the Earth) it’s about 25 °C per km c. Not always uniformV. Heat Movementa. 3 Ways Heat Moves1. Convection (energy transfer via motion)2. Radiation (energy transfer via radiating waves)3. Conduction (transfer of energy via