Vicky Veritas<p>I’ve posted about the Great Unconformity several times now (and you still must capitalize it), and had the chance to see it when visiting the Red Rock Canyon Conservation Area in Las Vegas. </p><p>After almost 5 years, I didn’t trust I’d be able to find it again. I decided to search Google maps and sure enough, there it was. Thank you to the wonderful person who put it on the map, and thank you Google for adding it! See the location below. </p><p>In the last picture it is in the rocks near the left of the picture where the trail can be seen and the metal sign is standing (zoom in). They are the same rocks layers known as the Great Unconformity at the bottom of the Grand Canyon in an easily accessible part of Las Vegas. You’re welcome.</p><p>The Great Unconformity<br /><a href="https://maps.app.goo.gl/THA4SbtdXtqvVotVA?g_st=ic" target="_blank" rel="nofollow noopener noreferrer" translate="no"><span class="invisible">https://</span><span class="ellipsis">maps.app.goo.gl/THA4SbtdXtqvVo</span><span class="invisible">tVA?g_st=ic</span></a></p><p>Refresher:<br />Tapeats Sandstone - 525 million years old<br />Vishnu Schist - 1.7 billion years old<br />Time Gap of 1.2 billion years = The Great Unconformity</p><p><a href="https://c.im/tags/TheGreatUnconformity" class="mention hashtag" rel="tag">#<span>TheGreatUnconformity</span></a> <a href="https://c.im/tags/LasVegas" class="mention hashtag" rel="tag">#<span>LasVegas</span></a> <a href="https://c.im/tags/FrenchmanMountain" class="mention hashtag" rel="tag">#<span>FrenchmanMountain</span></a> <a href="https://c.im/tags/TapeatsSandstone" class="mention hashtag" rel="tag">#<span>TapeatsSandstone</span></a> <a href="https://c.im/tags/VishnuSchist" class="mention hashtag" rel="tag">#<span>VishnuSchist</span></a> <a href="https://c.im/tags/TheGrandCanyon" class="mention hashtag" rel="tag">#<span>TheGrandCanyon</span></a> <a href="https://c.im/tags/geology" class="mention hashtag" rel="tag">#<span>geology</span></a></p>
Recent searches
No recent searches
Search options
Only available when logged in.
c.im is one of the many independent Mastodon servers you can use to participate in the fediverse.
C.IM is a general, mainly English-speaking Mastodon instance.
Administered by:
Server stats:
2.9Kactive users
c.im: About · Status · Profiles directory · Privacy policy
Mastodon: About · Get the app · Keyboard shortcuts · View source code · v4.3.6
#thegreatunconformity
0 posts · 0 participants · 0 posts today
Vicky Veritas<p>Snowball Earth</p><p>Through many posts we have talked about the Great Unconformity (yes, you must capitalize it) and how it occurs worldwide in different rock sections. Why? Scientists believe that at several times in Earth’s history the planet was buried in a blanket of ice. Oceans were nearly frozen. This is what scientists call Snowball Earth, or sometimes Slushball Earth.</p><p>The last occurred sometime before 650 million years ago, during the aptly named Cryogenian period. In 200 million years, uplift and the giant erosive conveyor belts of ice eroded continents down to the roots of the ancient mountains and left the land at sea level. Think the Canadian Shield. This scraped bare land is the base of the Great Unconformity. As the glaciers melted, sea level rose and covered the land and deposition of sedimentary layers began. Variations of this happened worldwide. We can focus on the North American continent which looked much different at that time. Forget anything west of Idaho or so. It wasn’t there yet.</p><p>Wyoming Geologist Myron Cook does a much better job than I could of explaining Snowball Earth, the Great Unconformity, and why different gaps, between hundreds of millions to billions of years of time, exist across what was North America at the time in his great video published only 11 days ago. Throw in a master-class in Deep Time, and you have it all put together as only a master story teller can. And there are lots of rocks, yay! Watch this wonderful video. Yes, it’s long, but you’ll absolutely hate yourself if you don’t get to see the Mineral Fork Tillite and how the story ends. Trust me.</p><p><a href="https://youtu.be/LXzDfQyUlLg" target="_blank" rel="nofollow noopener noreferrer" translate="no"><span class="invisible">https://</span><span class="">youtu.be/LXzDfQyUlLg</span><span class="invisible"></span></a></p><p>Follow it up with further findings on Snowball earth using thermochronology by Kalin T. McDannell, et. al. including our own <span class="h-card" translate="no"><a href="https://fosstodon.org/@brenhinkeller" class="u-url mention">@<span>brenhinkeller</span></a></span> as they work to help determine if glaciation or the recent hypotheses of tectonic influence had more impact on denudation of the continent. Spoiler alert: read the title of this post again.</p><p><a href="https://www.pnas.org/doi/full/10.1073/pnas.2118682119" target="_blank" rel="nofollow noopener noreferrer" translate="no"><span class="invisible">https://www.</span><span class="ellipsis">pnas.org/doi/full/10.1073/pnas</span><span class="invisible">.2118682119</span></a></p><p>Another version here: <a href="https://eos.org/articles/erasing-a-billion-years-of-geologic-time-across-the-globe" target="_blank" rel="nofollow noopener noreferrer" translate="no"><span class="invisible">https://</span><span class="ellipsis">eos.org/articles/erasing-a-bil</span><span class="invisible">lion-years-of-geologic-time-across-the-globe</span></a> </p><p>Pinging <span class="h-card" translate="no"><a href="https://mstdn.party/@BoxcarMurphy" class="u-url mention">@<span>BoxcarMurphy</span></a></span> who probably knows all about this already :)</p><p><a href="https://c.im/tags/SnowballEarth" class="mention hashtag" rel="tag">#<span>SnowballEarth</span></a> <a href="https://c.im/tags/SlushballEarth" class="mention hashtag" rel="tag">#<span>SlushballEarth</span></a> <a href="https://c.im/tags/Glaciation" class="mention hashtag" rel="tag">#<span>Glaciation</span></a> <a href="https://c.im/tags/Cryogenian" class="mention hashtag" rel="tag">#<span>Cryogenian</span></a> <a href="https://c.im/tags/TheGreatUnconformity" class="mention hashtag" rel="tag">#<span>TheGreatUnconformity</span></a> <a href="https://c.im/tags/NorthAmericanContinent" class="mention hashtag" rel="tag">#<span>NorthAmericanContinent</span></a> <a href="https://c.im/tags/DeepTime" class="mention hashtag" rel="tag">#<span>DeepTime</span></a> <a href="https://c.im/tags/MyronCook" class="mention hashtag" rel="tag">#<span>MyronCook</span></a> <a href="https://c.im/tags/HowSnowballEarthLeveledTheContinentsAndCreatedTheGreatUnconformity" class="mention hashtag" rel="tag">#<span>HowSnowballEarthLeveledTheContinentsAndCreatedTheGreatUnconformity</span></a> <a href="https://c.im/tags/WatchTheDamnVideo" class="mention hashtag" rel="tag">#<span>WatchTheDamnVideo</span></a> <a href="https://c.im/tags/geology" class="mention hashtag" rel="tag">#<span>geology</span></a> <a href="https://c.im/tags/ScienceMastodon" class="mention hashtag" rel="tag">#<span>ScienceMastodon</span></a> @geology</p>
Vicky Veritas<p>The Great Unconformity</p><p>Left to right on top of my notebook are:<br />Tapeats Sandstone deposited 525 million years ago in a beach environment.<br />Zoraster Granite emplaced 1.7 billion years ago. <br />Vishnu Schist 1.8 billion years ago.</p><p>Both of the bottom layers are the roots of mountains that eroded away.</p><p>Right where my foot is, the contact between the Tapeats and the Zoraster, there is over a BILLION years missing in the rock record called an unconformity. It was named the Great Unconformity by John Wesley Powell, and yes, you need to capitalize it.</p><p>These rocks can be seen at Frenchman's Stop in the Frenchman Mountains outside of Las Vegas, and also at the bottom of the Grand Canyon.</p><p><a href="https://c.im/tags/geology" class="mention hashtag" rel="tag">#<span>geology</span></a> <a href="https://c.im/tags/unconformity" class="mention hashtag" rel="tag">#<span>unconformity</span></a> <a href="https://c.im/tags/TheGreatUnconformity" class="mention hashtag" rel="tag">#<span>TheGreatUnconformity</span></a> <a href="https://c.im/tags/TapeatsSandstone" class="mention hashtag" rel="tag">#<span>TapeatsSandstone</span></a> <a href="https://c.im/tags/ZorasterGranite" class="mention hashtag" rel="tag">#<span>ZorasterGranite</span></a> <a href="https://c.im/tags/VishnuSchist" class="mention hashtag" rel="tag">#<span>VishnuSchist</span></a> <a href="https://c.im/tags/EarthScientists" class="mention hashtag" rel="tag">#<span>EarthScientists</span></a> <a href="https://c.im/tags/rocks" class="mention hashtag" rel="tag">#<span>rocks</span></a> <a href="https://c.im/tags/ScienceMastodon" class="mention hashtag" rel="tag">#<span>ScienceMastodon</span></a></p>
ExploreLive feeds
Mastodon is the best way to keep up with what's happening.
Follow anyone across the fediverse and see it all in chronological order. No algorithms, ads, or clickbait in sight.
Create accountLoginDrag & drop to upload