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:''This page is on the geographical feature. For other meanings, see Mount's Bay (disambiguation).'' Mount's Bay ((コーンウォール語:Baya an Garrek))〔(Place-names in the Standard Written Form (SWF) ) : (List of place-names agreed by the MAGA Signage Panel ). Cornish Language Partnership.〕 is a large, sweeping bay on the English Channel coast of Cornwall, England, United Kingdom, stretching from the Lizard Point to Gwennap Head on the eastern side of the Land's End peninsula. Towards the middle of the bay (and probably the origin of the name) is St Michael's Mount.〔Ordnance Survey: Landranger map sheet 203 ''Land's End'' ISBN 978-0-319-23148-7〕 Presenting a benign aspect to summer visitors of a large, scenic, natural harbour, in an onshore winter gale it presents a great danger to shipping as a "maritime trap", especially in the days of sailing ships with an excess of 150 known wrecks in the nineteenth century.〔Corin, J and Farr, G. (1983) ''Penlee Lifeboat''. Penzance: Penzance and Penlee Branch of the RNLI.〕 ==Geography and geology== Mount's Bay is the biggest bay in Cornwall. Its half-moon shape is similar to that of Donegal Bay in Ireland and Cardigan Bay in Wales, although, unlike the aforementioned bays, Mount's Bay is relatively sheltered from the prevailing Atlantic westerlies. It is, however, a danger to shipping during onshore southerly and south-easterly gales.〔 The coast is approximately 42 miles (67 km) miles from Lizard Point to Gwennap Head.〔http://www.southwestcoastpath.com/main/walks_content/distanceCalculator.cfm〕 Heading north and west from Lizard Point, the serpentine and hornblende schist cliffs reach a maximum height of 71 m (233 ft) at Vellan Head and are only broken by small streams and coves such as at Kynance, Gew-grade and Mullion Cove.〔Lawman, J. (1994) ''A Natural History of the Lizard Peninsula''. Pool: Institute of Cornish Studies.〕 After Gunwalloe Fishing Cove the cliffs have the softer look of Devonian Meneage Formations of greywacke and mélange, with erosion a problem west of the naturally dammed ria of Loe Pool. West of Porthleven there are high Devonian slate and granite cliffs to Rinsey Head after which the cliffs are topped by Pleistocene periglacial head and have eroded to form sandy beaches such as those at Praa Sands and Kenneggy. These beaches are in deficit and the cliff line is retreating.〔http://projects.exeter.ac.uk/geomincentre/02MOUNTS%20BAY.pdf〕 With the exception of the harder Devonian dolerite and gabbro of Cudden Point, the low, eroding cliffs and beaches continue to Mousehole. This part of the bay is the most populated with the towns of Penzance and Marazion and the villages of Newlyn and Mousehole. Beyond Mousehole the granite cliffs, rise to 60 m, and are broken by small streams such as at Lamorna Cove and Penberth. There are small sand dune systems at Church Cove and Poldhu Cove, Porthleven Sands, Praa Sands and from Marazion to Eastern Green, Penzance. The former sand dunes of the Western Green are now covered by Penzance promenade. All, but Marazion to Penzance, are examples of bay dune systems which develop where there is a limited supply of sand trapped within the shelter of two rocky headlands. Church and Poldhu Coves are SSSI〔http://www.sssi.naturalengland.org.uk/citation/citation_photo/2000125.pdf〕 and also have associated climbing dunes which occur when sand is blown inland of the main dune system.〔Tonkin, B., Covey, R. and Moat T. (1997) ''Start Point to Land’s End Maritime Natural Area''. A Nature Conservation Profile. Truro: English Nature.〕 Evidence of higher sea-levels in the past can be seen at Marazion where the town is built on a raised beach. A second example is the road between Newlyn and Mousehole. Sea levels rise and fall as the ice sheets advance and retreat, and raised beaches now mark the interglacial periods when sea levels were higher.〔 Either side of Penzance, on the beaches at Ponsandane and Wherrytown, evidence of a 'submerged forest' can be seen at low tide in the form of several fossilised tree trunks.〔Pool, P. A. S. (1974) ''The History of the Town and Borough of Penzance.'' Penzance: The Corporation of Penzance.〕 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「Mount's Bay」の詳細全文を読む スポンサード リンク
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