This is occurring today in Hawaii, perhaps the most well-known example of a hotspot track. Here, volcanic activity on the Island of Hawaii is slowly being replaced by activity on nearby Loihi seamount. The Hawaiian hotspot is believed to have been active at least 70 million years, producing a volcanic chain that extends 6,000 kilometers (3,750 miles) across the northwest Pacific Ocean. Plate above hotspot in Hawaii moves 9cm/year 6)The breakup of Pangaea (when?)
■ Paleoclimatic evidence: Placing Pangaea over the Late Paleozoic South Pole, Wegener predicted rocks defining Pangea climate belts. ■ Fossil Evidence: Identical fossils found on widely separated land. These organisms could not have crossed an ocean. ■ Matching Geologic Units: Distinctive rock assemblages and mountain belts match across the Atlantic. 7) Native metals as minerals a. Minerals are classified by their dominant anion. ➔ Native metals (Cu, Au, Ag) ◆ Examples: ● Copper (Cu) ● Gold (Au) ● Silver (Ag) Lecture recoding 10/5/2017 at 28:09 Can form a silver gold alloy called electrum Can also get purely metalic iron, not combined with oxygen or silica From Wikipedia A native metal is any metal that is found in its metallic form, either pure or as an alloy , in nature. [ citation needed ] Metals that can be found as native deposits singly or in alloys include aluminium , antimony , arsenic , bismuth , cadmium , chromium , cobalt , indium , iron , manganese , molybdenum , nickel , rhenium , selenium , tantalum , tellurium , tin , titanium , tungsten , vanadium , and zinc , as well as two groups of metals: the gold group, and the platinum group . The gold group consists of gold , copper , lead , aluminium , mercury , and silver . The platinum group consists of platinum , iridium , osmium , palladium , rhodium , and ruthenium . Amongst the alloys found in native state have been brass , bronze , pewter , German silver , osmiridium , electrum , white gold , and silver-mercury and gold-mercury amalgam . Only gold, silver, copper and the platinum metals occur in nature in large amounts. Over geological time scales, very few metals can resist natural weathering processes like oxidation , which is why generally only the less reactive metals such as gold and platinum are found as native metals. The others usually occur as isolated pockets where a natural chemical process reduces a common compound or ore of the metal, leaving the pure metal behind as small flakes or inclusions. Non-metallic elements occurring in the native state include carbon and sulfur . Silicon , a semi-metal, has been found in the native state on rare occasions as small inclusions in gold.  Native metals were prehistoric man's only access to metal, since the process of extracting metals from their ores, smelting , is thought to have been discovered around 6500 BC. However, they could be found only in relatively small amounts, so they could not be used extensively. So while copper and iron were known well before the
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- Fall '09
- Plate Tectonics, Aluminium, Volcano, Basalt