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Posts treating: "diameters"

Sunday, 01 May 2016

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New Madrid Fault Zone Activated by Oklahoma 

Ontario-geofish [2016-05-01 13:05:00]  recommend  recommend this post  (182 visits) info

 US
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Most likely.  I must be getting old adding qualifications.  I usually call it 'absolute' if it's over 80% correct, and I believe in this. Earthquake season has started with the arrival of gas frack waste to OK.  If you do a discrete element analysis you will find that disturbance extends several diameters from the main source.  New Madrid is definitely within this zone.  But NM is

458-Million Year Old Twin Impact Craters Found in Sweden 

Palaeoblog [2015-09-17 13:39:00]  recommend  recommend this post  (200 visits) info

 SE
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Scientists in Sweden have found two craters south of the city of Östersund with diameters of 7.5 and 0.7 kms. The two meteorite impacts occurred at the same time, 458 million years ago. “From studies of meteorites, we know that a large disruption of an asteroid occurred around 470 million years ago in the asteroid belt between Mars and Jupiter.” “This disruption spawned large amounts

Mystery Rock Found in Waldron Shale Pile 

Louisville Area Fossils [2010-11-22 03:12:00]  recommend  recommend this post  (716 visits) info

 Silurian,Carboniferous,Devonian
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This rock was found in a pile of Silurian Period Waldron Shale next to a busy parking lot.  One side of it has a black layer that attracts a magnet.  [I sometimes test things found with rare earth magnets after watching the Science Channel show Meteorite Men.] The rest of the rock does not appear to be limestone.  As an experiment, another rock with a horn coral in it known to be Waldron Shale was exposed to vinegar.  It began to fizz.  Vinegar was then applied to this [...]

Manganese Nodules 

JOIDES Resolution blogs [2010-11-01 17:54:21]  recommend  recommend this post  (15 visits) info
Several of the cores from site U1366 had manganese nodules within the sediments. Diameters varied from about 5 cm to just under 7 cm. The diameter of the core liner is 7 cm, so you can use that as you look at the photos today. Manganese nodules are believed to grow extremely slowly on the seafloor as material from the ocean water precipitates around a nucleus. read

Natural gas pipelines in Arizona 

Arizona Geology [2010-09-14 18:53:00]  recommend  recommend this post  (10 visits) info
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Where are the large diameter natural gas pipelines in Arizona?That was a question we got last night from someone apparently concerned over the gas line rupture and explosion in California.The map at right is Figure 3 in AZGS Circular #30, "Arizona Has Salt." Interstate pipelines, with diameters of 30-inches are shown by the heavy dark lines. The thinner lines are intrastate pipelines, and

Symmetrical Wave Ripple Marks 

Olelog [2010-01-26 14:40:25]  recommend  recommend this post  (27 visits) info

 Devonian
In water ripples can be formed by currents or by waves. Currents produce asymmetrical ripples, often with sinuous crest lines. Wave ripples are generally symmetrical, usually with rather straight crest lines. Wave-formed ripple marks, also known as bidirectional ripples, or symmetrical ripple marks, have a symmetrical, almost sinusoidal profile; they indicate an environment with weak currents where water motion is dominated by wave oscillations. Waves As illustrated by the red dot in the [...]

Help to the Gulf Stream 

Olelog [2009-12-04 17:13:00]  recommend  recommend this post  (37 visits) info
There has been some worry that the Gulf Stream might be hindered in doing its good work for north western Europe as a consequence of global warming, but now it seems that another consequence of the same global warming in another corner of the world might save its life. Unexpected help may come from the Agulhas Current.The Agulhas Current flows down the east coast of Africa from 27°S to 40°S. It is narrow, swift, and one of the strongest ocean currents in the world. Southwest of Cape Town it [...]

Pockmarks in Spitsbergen Fjords 

Olelog [2009-09-09 11:05:14]  recommend  recommend this post  (20 visits) info
In my latest post I mentioned the open access to the Norwegian Journal of Geology. In this post I shall concentrate on a paper in their latest issue (2009 Volume 89 Nr. 1 & 2) - Pockmarks in Spitsbergen fjords.Pockmarks are concave, crater-like features on the seafloor, generally up to several hundreds of meters in diameter and tens of meters in relief. ’Mega pockmarks’ can have diameters of more than 1.5 km and depths exceeding 150 m. The formation of pockmarks is mostly caused by the [...]
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