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Rick Britton

Miscellaneous  - 
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Scott Brande
moderator

Geology Photos  - 
 
Doorstop disappeared. I solved the problem. Geology - "git 'er done".
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Glen Collins's profile photoEssam Aboud's profile photo
2 comments
 
geologic mind,,,,,,,,,,,,,,,,,, Amazing
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More rime ice photos, this time with a few birds:
Well, it's weeks later, and I'm not up in the far northlands of Southcentral AK anymore (but instead are in the snowy middle-lands of the ...
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todd comer

Geology Photos  - 
 
Interesting bit I ran across while converting some old video, featuring a litte peek into Hell (Grand Cayman), which hosts a unique erosional formation known as phytokarst.
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Olivier Malinur

Structure-Tectonics  - 
 
The Complete Rock Cycle

I very well see this in one of those 1960s-1980s kids science books. Complex and simple enough. Tbh, I don't know the source. I used it as a support to explain geology to complete newbies, in 1 day.
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PDS Gentra's profile photoMart Rootamm's profile photo
2 comments
 
'nonconformity', 'disconformity', 'planktonic ooze' :-)

I also like the big fish and small fish (:

And my goodness, so many new words besides.

Estonia has limestone, dolostone, lots of peat, and oil shale. Also gravel, sand, silt, mud, clay (par for the course). We have lots of bogs and swamps, too.

I searched by image at Google, and got the following results:

One very possible source of the picture is this site, run by Phil Stoffer:
http://www.geologycafe.com/class/chapter2.html
The image there is a lot bigger.

The Geology Cafe was referred to by this site:
http://aquadoc.typepad.com/waterwired/2013/06/the-illustrated-rock-cycle.html
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Silver Fox

Geoblogs  - 
 
Sorry if this is a duplicate, but it looks like the original post was put in the spam folder:
 
A little more about ice in +Evelyn Mervine's post from 2015:
def. Ice: Water (H 2O) in a solid state. When naturally occurring, ice is considered a mineral. There are many forms of ice: lake ice, river ice, sea ice, snow, glaciers, ice caps, ice sheets, and frozen ground (such as permafrost). If you ask a geologist what he or she considers to be Earth's most important ...
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Luca Congedo

Geography-Geospatial  - 
 
Tutorial about wildfire monitoring using Landsat and MODIS images with the Semi-Automatic Classification Plugin for QGIS.
https://www.youtube.com/watch?v=-1LJIJFTemw

https://fromgistors.blogspot.com/2017/01/wildfire-monitoring.html
This tutorial describes a method for monitoring wildfires using SCP and the freely available images acquired by Landsat and MODIS. Monitoring wildfires and assessing burn severity are crucial activities for the protection of...
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Charles Carrigan
owner

Planetary Geology & Meteorites  - 
 
A new paper just published online in ScienceAdvances gives new data on the age of the moon as being 4.51 Ga, not a younger 4.45 Ga age as has been proposed by others. This suggests the moon was differentiated and solidified just ~60 million years after the formation of early solar system materials. 
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Rodney Bedford

Funny Stuff  - 
 
Curiosity rover talks to Opportunity rover Mayhem ensues
https://youtu.be/OjEc6Bq_y9A
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Giulia Sofia

Meetings & Journal Articles  - 
 
looking for perspective abstracts in geomorphometry at EGU2017!! there is still time to submit, untill jan 11, hrs 13.00 CET

http://meetingorganizer.copernicus.org/EGU2017/session/24133

looking forward to see your presentation!
This session is inter-disciplinary with a focus on new techniques in digital terrain production and analysis independent of the subject, and/or field. Any insights are welcome but a clear, if perhaps embryonic or potential, link to a process sculpting the Earth's surface is preferred. The session's aim is to ...
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Irina T.

Geophysics  - 
 
"Japanese scientists believe they have established the identity of a "missing element" within the Earth's core.
They have been searching for the element for decades, believing it makes up a significant proportion of our planet's centre, after iron and nickel.
Now by recreating the high temperatures and pressures found in the deep interior, experiments suggest the most likely candidate is silicon."
Scientists believe they have established the identity of a "missing element" in the Earth's core.
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nestor umali's profile photo
3 comments
 
we might say.... a very interesting facts!
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About this community

Please read the community guidelines before posting: http://bit.ly/11qsoxE Geoscience is the study of the Earth from a variety of aspects, and includes sciences such as geology, paleontology, oceanography, meteorology, geography, planetary geology, and others. Many issues in our world today rely on geoscience, such as earthquakes & other natural hazards, natural resources, environmental issues, land use, climate change, and many others. This is a public community. Anyone can join; all posts are public and can be found in Google Search.
Earth & other planets

David Carlson

Geophysics  - 
 
AQUEOUS DIFFERENTIATION OF KUIPER BELT OBJECTS (KBOs):

Abstract:
This article suggests an alternative extraterrestrial origin for metamorphic gneiss, along with its associated mantling rock of quartzite, carbonate rock and schist. Authigenic gneissic sediments are suggested to have been precipitated in the cores of Kuiper belt objects (KBOs) undergoing 'aqueous differentiation', with aqueous differentiation caused by orbital perturbation.

Our suggested former binary brown-dwarf Companion to the Sun perturbed binary KBOs to spiral in and merge during the Archean Eon, catastrophically forming authigenic sedimentary cores with a typically tonalite–trondhjemite–granodiorite (TTG) composition, characteristic of Archean cratons.

The tidal inflection point (associated with the former Sun-Companion solar system barycenter) is suggested to have initiated orbital perturbation of KBOs. The tidal inflection point spiraled out from the Sun at an exponential rate, passing through the cubewanos of the Kuiper belt from 4.1 to 3.9 Ga, causing the late heavy bombardment of the inner solar system. The growing Sun-Companion eccentricity around the solar system barycenter, which caused the tidal inflection point to spiral out from the Sun, was driven by the spiral in of the binary brown-dwarf components of binary-Companion.

Solitary KBOs, which did not undergo catastrophic binary spiral-in merger, may have experienced smaller, repeated instances of aqueous differentiation, forming multiple gneiss domes in KBO cores, compared to catastrophic binary spiral-in merger which formed TTG cores.

Finally, perturbation by binary-Companion came to an end when the binary brown-dwarf components ultimately merged at 542 Ma in an asymmetrical merger explosion that gave the Companion escape velocity from the Sun.

Neptune became the nemesis of the Kuiper belt in the new Phanerozoic Eon, with the loss of the perturbing and stabilizing influence of the Companion at 542 Ma, with Neptune causing orbital perturbation of KBOs in newly-unstable orbits. Neptune also caused smaller instances of aqueous differentiation, such as forming the Eocene gneiss domes which are scattered through the Middle East from Greece to Nepal. Neptune is responsible for injecting KBOs into the inner solar system in the Phanerozoic Eon, likely by the intermediate pathway of the minor-planet centaurs.

Sedimentary KBO cores lithify into TTG cores and gneiss domes, with subsequent metamorphism occurring as saltwater oceans freeze solid. The expansion of water ice in solidifying KBO oceans builds the tremendous pressure which causes high-pressure metamorphism in extraterrestrial metamorphic rock.

Perturbation of KBOs into the inner solar system by Neptune cause extinction event impacts on Earth, with highly-compressible KBO ices generally clamping the Earth-impact shock-wave pressure below the melting point of silicates, masking the impact origin of the continental tectonic plates.
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Ptygmatic Folds in gneiss migmatite from Helsinki Finland
–used with permission of Sameli Kujala
http://www.flickr.com/photos/sameli/2040126969/
Abstract: This section suggests an alternative extraterrestrial origin for metamorphic gneiss, along with its associated mantling rock of quartzite, carbonate rock and schist. Authigenic gneissic s…
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Ann Pu

Mineral Resources  - 
 
 
The color in amethyst from most localities is unevenly distributed in the individual crystals.
When heated to more than about 300-400°C, amethyst loses its violet color and often turns yellow, orange or brown, and then resembles the quartz variety citrine, but depending on the locality and the temperature during the heat treatment it may also turn colorless or - rarely - green.
(Neumann and Schmetzer, 1984).
#amethyst #crystal #violet #colors #mineralogy
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Rick Britton

Geology Photos  - 
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Charles Carrigan's profile photo
3 comments
 
Make the continents Great Again!! 😂😂😂
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Irina T.

Volcanology  - 
 
In essence, this article points to the website of the Global Volcanism Program.
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Irina T.

Climate Change  - 
 
 
Interesting. The 1815 Mt. Tambora eruption in Indonesia caused fishermen in New England, USA, to change the type of fish to catch. "Hundreds of articles have been written about the largest volcanic eruption in recorded history, at Indonesia’s Mt. Tambora just over 200 years ago. But for a small group of New England-based researchers, one more Tambora story needed to be told, one related to its catastrophic effects in the Gulf of Maine that may carry lessons for intertwined human-natural systems facing climate change around the world today.

In the latest issue of Science Advances, first author research fellow Karen Alexander at the University of Massachusetts Amherst and 11 others including aquatic ecologists, climate scientists and environmental historians recount their many-layered, multi-disciplinary investigation into the effects of Tambora’s volcanic winter on coastal fish and commercial fisheries.
[...]
In the early 1800s alewives were a “utility fish,” an important commercial export but also used locally as chicken feed, garden fertilizer and human food during the winter. The winter of 1816 was so cold, Alexander says that “Penobscot Bay froze solid from Belfast to Castine.” When alewives arrived at their seasonal spawning time, adverse conditions likely disrupted spawning runs, increased natural mortality and, critically for the people depending on them, decreased catch.

She adds, “During this climate crisis, people couldn’t catch enough alewives to meet their needs, so they quickly turned to mackerel, the next abundant species to arrive along the coast. Pursuing mackerel and rapidly distributing it to communities with no other sources of food fundamentally altered the infrastructure of coastal fisheries.” Although records suggest that alewife populations apparently recovered within 25 years, “people responded rapidly and effectively to Tambora in only five years and never looked back when the crisis passed.”"
Hundreds of articles have been written about the largest volcanic eruption in recorded history, at Indonesia’s Mt. Tambora just over 200 years ago. But for a small group of New England-based researchers, one more Tambora story needed to be told, one related to its catastrophic effects in the Gulf of Maine that may carry lessons for intertwined human-natural systems facing climate change around the world today.
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A little more about ice in +Evelyn Mervine's post from 2015:
def. Ice: Water (H 2O) in a solid state. When naturally occurring, ice is considered a mineral. There are many forms of ice: lake ice, river ice, sea ice, snow, glaciers, ice caps, ice sheets, and frozen ground (such as permafrost). If you ask a geologist what he or she considers to be Earth's most important ...
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Mustapha Hallouane's profile photo

Joaquín del Val

Geology Photos  - 
 
Cross-stratification in an aeolian dune of late Pleistocene, made up of coarse-grained sand cemented by calcium carbonate. I took this picture two months ago at Cape Trafalgar (south Atlantic Spanish Coast) 
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Joaquín del Val's profile photonestor umali's profile photo
7 comments
 
thanks Charles for the Info's!
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Mounir Roukky

News Links  - 
 
NASA Recently Reveals Image of Earth And Moon Pictured from Mars by HiRISE
The National Aeronautics and Space Administration (Nasa) recently released an amazing photo of earth and moon taken from mars.
check out the pic and Read More on the incredible HiRISE camera | https://goo.gl/HIodPE
Ps: Real picture is within the article. 
Earth and Moon photo’s is photographed by the use of the High-Resolution Imaging Science Experiment HiRISE. HiRISE camera functions as the human eyes...
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Dawn Pearce

Volcanology  - 
 
Isn't this an unusual volcanic mound?
 
Piton volcanique du "Hombori Tondo" (point culminant du Mali , 1155m)
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nestor umali's profile photo
4 comments
 
good photo! the top of the mountain looks like a figure of a walking elephant.
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