32. Flood basalts Dan Barker April 2009 Creag Mhor, Isle of Mull, Scotland.
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32. Flood basalts Dan Barker April 2009 eag Mhor, Isle of Mull, Scotland
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Transcript of 32. Flood basalts Dan Barker April 2009 Creag Mhor, Isle of Mull, Scotland.
32. Flood basaltsDan Barker April 2009
Creag Mhor, Isle of Mull, Scotland
About 55 million years ago, while the North Atlantic opened up, enormous outpourings of basalt lava covered western Scotland, Northern Ireland, and eastern Greenland. Creaga Ghaill, Mull.
Thick stacks of lava flows built up in a few million years. Mostflood basalts erupt from long fissure systems, not from a central vent. Bearraich. Mull
Floddigarry, Isle of Skye
Struan, Isle of Skye
The same thing happened in NE Africa, starting about 40million years ago. 89 km south of Asmara, Eritrea
The Simien Mountains, Ethiopia, are a spectacular remnantof these flood basalts.
Wrangellia Basalts, Vancouver Island, BC, formed 230 million years ago on an oceanic plateau in the SW Pacific, before colliding with North America.
Another view of the Wrangellia Basalts,Vancouver Island, BC
North America's youngest flood basalts cover about half ofWashington State. Columbia River Basalts, Snake River.
Eruption of the Columbia River Basalts, WA, peaked about16 million years ago, and 95% of the volume erupted in lessthan 1 million years.
Many Columbia River Basalt flows show prismatic joints, from interactions with surface water. Palouse River WA
There was enough time between flows for thick soils to develop. From Wishram Heights WA
The Dalles WA
Wanapum Basalt at the Dalles
Columbia River Basalts warped by an anticline, WA
