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Old 12-04-08, 02:17 AM   #2
Pillar
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Join Date: Sep 2002
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Perfect! Hitman you are my hero!

This is the relevant portion of the site:

Quote:
Bottom relief of the Black Sea

Black Sea is deep; central area of its bottom is an abyssal plain at 2000m depth, covered by silt sediments, it is an accumulation area of the basin. Maximal depth of the Black Sea is 2210m.



Black Sea shelf is a low gradient underwater slope to 100-150m depth; the shelf narrow (1-2.5km) at the mountainous coasts of the Black Sea (Caucasus, Crimea, Anatolia). The shelf is terminated by the abrupt (up to 20-30о) basin slope to the basin apron area with depths over 1000m. An exclusion is the shallow Nor-Western part of Black Sea all belonging to the shelf zone; actually it is not a part of the Black Sea hollow.



Bottom Sediments of the Black Sea

Nearshore shallow bottom is an underwater continuation of the beach: various types of sand or big rocks. Starting at 30-50 meters depth slow shelf slope is covered by sand, different size gravel, and molluscan shells. As the depth is growing, mussel Mytilus galloprovincialis shells are changed to Modiolus phaseolinus shell fragments; even deeper broken molluscan shells form fine silt covering the rest of Black Sea shelf.



Thickness of sediment layer of Black Sea abyssal plain varies from from 8 to 16 km, thicker in the Western part of the Sea, bordered by the central Black Sea meridional rise. Thickness of the recent sediments layer, accumulated during the last 3000 years of the modern Black Sea history is 20 to 80cm depending on the bottom region.



Sediment layer rests on the 5-10km thick basalt plate that covers the mantle. Intermediate granite layer between sediment and basalt layers is absent in the Black Sea (some fragments of granite layer were found in the Eastern part of the abyssal plain). Thus the Black Sea bottom exhibits features typical for the Ocean bottom.
Am I reading this correctly - that a "rocky" bottom in DW terms would typically represent *Basalt* and not Granite?

Also, most of the ocean floor is a layer of sediment (silt say) covering basalt?

If the answers are affirmative, this makes me wonder where one would find a *rocky* bottom... I've been playing DW (self made scenarios often) with rocky bottoms way too much.

Thanks mate...
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