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Michigan is a state within the USA that is not known for fossiliferous rocks, but there are some localities where fossils may be found. Most are from the Late Devonian period, others are from the Late Pleistocene period, the Silurian period, and Carboniferous periods. However, small amounts of Precambrian period fossils consisting of stromotolites, metazoans and algal can be found in Precambrian outcrops located in Michigans Upper Peninsula. http://www.michigan.gov/documents/deq/MFP_5_Fill_In_The_Blanks_301808_7.pdf The oldest megascopic fossils found in Michigan have been found in the Negaunee iron formation near Palmer, MI at the Empire Mine. The fossils are of a primitive, filament-like ancestor of algae. Scientists have determined the fossils to be 2.1 billion years old. http://www.michigan.gov/documents/deq/Oldest_Fossil_304663_7.pdf They are found in thin layers in one section of the mine. The fossil is known as Grypania cf. spiralis which is preserved as a corkscrew-shaped, or spaghetti like marks that look like random O's, C's and 6's. * Devonian fossils of Michigan are marine, consisting of brachiopods, crinoids, corals, bryzoans, trilobites, gastropods, fish, blastoids, and cephalopods. * Carboniferous fossils are usually found in central Michigan, and are not usually well preserved. Near St. Charles, Michigan there is a site that has plants in good preservation, but this site is nearly impossible for the amateur to access. * Silurian fossils are usually found on the shores of the Great Lakes, often as Petoskey stones. This is revealed by the presence of the index fossil Halysites. * Pleistocene fossils are few and far between, often found by construction workers or farmers. The chance of finding a mammoth or mastodon is very low. Higher quality fossils are found mostly in the northern region of the Lower Peninsula. ==Localities== Many of Michigan’s fossil sites are located on lake shores. An example is Point Betsie, near the small town of Frankfort, Michigan. Erosion from wave action sometimes damages the fossils but fossils such as corals or bryzoans can be found here. In northern Michigan there are limestone quarries and drop-off sites where limestone has been transferred from those quarries. Both the quarries and the stop-off sites can sometimes be rich in fossils including invertebrates and armored fish, or placoderms as well as gastropods, cephalopods, and trilobites. The abandoned Rockport Quarry Alpena, is considered to be a rich locality, but permission must be applied for a month in advance. Active quarries cannot be accessed without the permission of the owners. Quarries in general area hazardous places with falling rocks, limestone dust and quarry trucks, so caution is necessary for fossil hunters. The Besser Museum fossil park in Alpena has limestone brought in from this quarry, so the amateur may enjoy fossil hunting without the hassle. One part of the park is free for all; you must pay to get into the other part, but it has better fossils. Visitors may take as much as they want from the park, but are not allowed to take from the blocks that form the barrier walls, for safety reasons. Another type of Michigan fossil site is the quarry drop off. This is when quarries put backfill in areas that have been dubbed unusable or abandoned for building. These sites are usually large piles of rock that appear to be out of place, and usually are in public places. The advantages to these sites is that they are easy to find, and are easy to access. They usually yield close to quarry-quality fossils, and require no digging to access, but the fossils have been exposed to the weather and have been picked up and transported by large vehicles, thus some fossils are scraped and gouged. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Michigan fossil hunting」の詳細全文を読む スポンサード リンク
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