Where on (Google) Earth #191?

It didn’t take me long to find the Goat Paddock Crater in Western Australia that Michael Cohen featured in Where on (Google) Earth #190. Impact craters are really easy to spot, particularly with the help of compilations like the Consolidated Impact Crater Database. I recognized the color of the landscape as Australia right off the bat and it didn’t take long to find this distinctive hole in the ground. That’s why it’s called the Schott Rule

It’s also really good to see WoGE getting competitive again and bringing in new winners. In fact, Michael’s new geoblog, From Saturn, With Love, is only the most recent to be inspired by winning a WoGE contest. Here’s hoping it will grow steadily in both content an visitors!

Since I had so much fun stumping the geoblogosphere with a river last time I hosted WoGE, I figure it’s only fitting to see if you’ve gotten any more familiar with fluvial landscapes since then. And since I like the wide-open race to discover these, I’m not invoking the Schott Rule this time. Just find the image below in Google Earth, and comment below with its latitude and longitude and a little about the geological significance of the site. Simple as that…

Where on (Google) Earth #191.

Happy exploring!

Day #64 Deskcrop: Arkosic Arenite

We’ll end the work week with a deskcrop from high in the Colorado Rockies: an arkosic arenite (sandstone) from Vail Pass, Colorado. This rather immature sedimentary rock is rich in both K-feldspar and micas, giving it its distinctive reddish color. The rock has a Pennsylvanian depositional age, and was formed in association with the uplift of the Ancestral Rockies.

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Arkosic Arenite

Explore this and all of my 2010 Deskcrops and Outcrops in Google Earth!

Day #62 Deskcrop: Drusy Quartz in Limestone Vugs

Today’s deskcrop comes from a small knob that may no longer exist. The sample consists of drusy quartz that fills vugs in the Mississippian Leadville Limestone. The vugs were formed when the Leadville Limestone was exposed to surface weathering and developed a karst topography. The hill from which this sample was collected is thought to have been a paleokarst tower. Unfortunately, when I last visited the locality a few summers ago it was on the verge of being blasted away to make room for a campsite.

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Drusy Quartz in Limestone Vugs



Opposite Side of the Knob, Where the Molas Lake Formation Redbeds Overly the Leadville Limestone
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Explore this and all of my 2010 Deskcrops and Outcrops in Google Earth!

Day #61 Deskcrop: Halite & Sylvite

One final salacious deskcrop and I promise I’ll move on from the evaporites that have dominated this series recently. Today’s deskcrop is the trophy block of halite (clear to grey) and sylvite (orange) that I was able to collect from the Kansas Underground Salt Museum this past Saturday. There isn’t much sylvite in this the Hutchinson Salt Beds, so I was rather pleased to be able to collect such a nice specimen. You can see more photographs I took in the mine/museum in this set on Flickr.

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Halite (clear to grey) & Sylvite (orange)

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Closeup: Note the Cubic Cleavage in Halite

One more tasty tidbit: the Kansas Underground Salt Museum has its own Twitter account! Follow them @650feetDown.

Explore this and all of my 2010 Deskcrops and Outcrops in Google Earth!

Day #60 Deskcrop: Saltsickles!

In the valley below the potash evaporation ponds featured yesterday there is an overhanging cliff of Permian Cutler Formation redbeds that is covered in the most remarkable Quaternary deposit…

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Salt Stalactites and Stalagmites

As well lined as the evaporation pools above are, some brine will inevitably leak out. As it seeps from the cliff above, it evaporates, and the resulting salt deposits (sheltered from rain by the overhanging cliff) form an amazing array of salt stalactites and stalagmites. Today’s deskcrop is a portion of one of those salt stalagmites (which are generally thicker and blunter than the soda-straw thin stalactites).

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Salt Stalagmite

Of course, no geology student worth their salt passes up the opportunity to do the obligatory physical properties test…

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Saltsickles!

Explore this and all of my 2010 Deskcrops and Outcrops in Google Earth!