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Sphakia A Physical Geography
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Crete sits on a plate boundary where the African Plate is being subducted under the European Plate Crete: Tectonic Setting
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Geological History Initial uplift during the Alpine Orogeny starting in the Late Cretaceous 70 mya(east) ending in Miocene 10 Mya (West) Stratigraphy is a series of Nappes caused by failure of uplifted masses due to East West Progression of uplift Pliocene submergence followed by uplift in the early Pleistocene and Block faulting
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Principal Rock Types Quartzite - metamorphic Carboniferous Platy Limestones Carboniferous to Eocene Crystalline Limestones Mesozoic Neogene Fills Late Tertiary Quaternary deposits
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Earthquakes and Subsidence Jolting Subsidence 4-1.5 ka (at least 11 stillstands) Byzantine Tectonic Paroxysm - Very rapid uplift of up to 10 m 1530+/-40 BP Associated with at least 11 historical reports of earthquakes between 344 and 553 AD Small quakes still common…last in 1994
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Climate Dry season May- November Wet Season November-April
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Rainfall
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White mountains snow and desert
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Climate History/Climate Change Pleistocene glaciation in highest areas, Wetter conditions assumed to drive erosion - Older Fill Arid conditions circa 16 ka gave way to moister Holocene conditions (based on pollen evidence) By 5 ka BP more arid conditions return (loss of tilia) Predicted Global Warming Impacts + 4 C - 10-40% precipitation
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Vegetation High degree of Endemism (180 species) Sphakia, the most wooded part of Crete (Cypress and Pine)
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Maquis and Phyrgana Controlled largely by Moisture
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Re-vegetation Comparisons with early Photography (Rackham) suggests this is associated with de-intensification of agriculture since 1850, particularly reduced stocking
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Cultivation Cultivation of Olives dates at least from Late Neolithic Continues today in irrigated groves Grain and Fruit
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Earth Surface Processes and Landforms in Crete
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Pleistocene Fans Dating from up to 300 ka Possible association with Glaciation
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Mountain Basins
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Gorges
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Formed in crystalline Limestone or Phyllite-Quartzite Support distinct vegetation (shade/moisture/very limited soils)
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Importance of Rare events I Dec 5th 2000
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Importance of Rare events II Maas, Macklin and Kirkby Small basin draining into Omalos Identify six main channel deposits Oldest 14400-3600 BP Last two 1968 and 1989
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Hillslope Processes
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Coastal Plain
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