and debris mixing with the water becomes a deadly mudflow which can travelup to 50km/hour.13.Major explosive super volcanoes of the past million years?Mt. Toba, caldera collapse (now Lake Toba which is 100km wide) – largest super volcanic eruption, x1000 the size of Mt. St. Helen’s, sent 14.Gneiss and other major metamorphic rock types.Gneiss: has distinct compositional/gneissic bands -Light bands = felsic minerals (quartz and feldspars) -Dark bands = mafic minerals (biotite and amphibole)You can change the rock type by pressure and temperature:Mudstone -> Shale protolith -> Slate LG (recystrallization for clay) -> Phyllite LG (neocrystallization of clay into mica) -> Schist IG (recrystallization of mica,
additional new minerals grow) -> Gneiss HG (decomposed mica, recombination and neocrystallization into quartz and feldspars)Roots of mountains, 20-30km depth in the earth, temperatures of 800-1000 degrees. Bands form by:1-Original layering on the protoliths2-Shearing stretching the rock, and streaking mafic components like mica across to form bands3-Metamorphic differentiation where minerals segregate into different layers, under great pressure and temperatures, slow solid-differentiation of the rockMigmatite = partially melted gneiss-both igneous and metamorphic rock15.Carbonate rocks: limestones, dolomites, marbleLimestone protolith -> metamorphism -> heat it and squeeze it = marble-can be non-foliated or can have bandsLimestone protolith-> diagenisis -> dolomites (Mg taking over the Ca)1.The "Big Bang" is our current best model for the origin and evolution of the Universe. Sequentially, starting with the moment of the "Big Bang" very briefly explain the evolution of the Universe. Address the formation of matter, expansion, cooling and the first cycle of stellar formation.-Matter forms within microseconds of the explosion by the condensation of quarks-In the next 5-10s, early atomic nuclei for hydrogen, deuterium, helium, and traces of beryllium and lithium form-Then, as the material expands and cools, it becomes cool enough for electrons to attach to the atomic nuclei, forming neutral atoms. Since neutral atomsare transparent, and ionized plasma before was not, the universe then became transparent.-As material expands, gravity begins to take over, reassembling the material together, generating heat and creating the earliest and largest stars. Through nucleosynthetic processes, elements up to iron in the period table are formed. Whereas elemente beyond iron are formed during the super-nova explosion of the star.2.Cascadia subduction zone off the west coast of Canada
-Convergent plate boundary, Juan de Fuca plate subducting under the North American plate-By looking at the magnetic striping around the ridge, we can see that the oldest material at the ocean floor of the Juan de Fuca ridge is no older than 10million years old-This means that all the material older than 10million years old has been subducting under the North American plate3.Major spreading ridges – especially the mid-Atlantic ridge and the East Pacific rise4.General classification and subclassification of igneous rocks (i.e.