Missourian Posted November 25, 2012 Share Posted November 25, 2012 Do you have photos showing the boundary between strata of two different geologic periods or epochs? If so, put 'em here.... Context is critical. Link to comment Share on other sites More sharing options...
Missourian Posted November 25, 2012 Author Share Posted November 25, 2012 (edited) I'll start things off.... Mississippian-Pennsylvanian boundary Burlington-Keokuk Limestone - Cherokee Group Osceola, Missouri Here, Pennsylvanian shale and sandstone fills a sinkhole formed in the deeply weathered Mississippian limestone. Edited November 25, 2012 by Missourian Context is critical. Link to comment Share on other sites More sharing options...
Paleoworld-101 Posted November 25, 2012 Share Posted November 25, 2012 I just posted this exact thing on your other thread, but since it holds more relevance here, i'll post it again: This is one of the sites where i collect at, which yields complete Glossopteris leaves. As you can see by the pic, it is a great place to see the Permian-Triassic boundary, notorious for being the most devastating extinction event in the planets history (95% of life wiped out in a geological blink). It is located at Austinmer, a coastal suburb between Sydney and Wollongong. "In Africa, one can't help becoming caught up in the spine-chilling excitement of the hunt. Perhaps, it has something to do with a memory of a time gone by, when we were the prey, and our nights were filled with darkness..." -Eternal Enemies: Lions And Hyenas Link to comment Share on other sites More sharing options...
Missourian Posted November 25, 2012 Author Share Posted November 25, 2012 i'll post it again: Thanks much. I hope there are many more to follow.... Context is critical. Link to comment Share on other sites More sharing options...
Missourian Posted November 25, 2012 Author Share Posted November 25, 2012 Precambrian-Cambrian boundary Vishnu Schist - Tapeats Sandstone Bright Angel Trail, Grand Canyon, Arizona It's just up the trail now: I couldn't tell where the trail crossed the boundary. Context is critical. Link to comment Share on other sites More sharing options...
Dromiopsis Posted November 25, 2012 Share Posted November 25, 2012 Hello! Here a small movie from the KT boundary in Denmark where I have hunted during 3 years. Now, When I come back from Sweden and my way back to France, I like to make a small stop there... It was this year, Beginning of April. Enjoy D Gallery pictures http://www.flickr.com/photos/supergrevling/ Link to comment Share on other sites More sharing options...
jpc Posted November 26, 2012 Share Posted November 26, 2012 nice video, dromiopsis... nice fossils. My pix of the KT boundary in Wyoming are lost in badly organized photos. Link to comment Share on other sites More sharing options...
Malcolmt Posted November 26, 2012 Share Posted November 26, 2012 I don't actually have a picture but there is a well defined layer exposed at Ridgemount quarry in Ontario, Canada where the Upper Silurian meets the Lower Devonian. Perhaps Pleecan might have a picture of this. Link to comment Share on other sites More sharing options...
Wrangellian Posted November 27, 2012 Share Posted November 27, 2012 Can I ask that people state whether there is an unconformity at their boundary, if they know it? For instance, Missourian, I believe there is one between the Vishnu and Tapeats? Link to comment Share on other sites More sharing options...
MikeR Posted November 28, 2012 Share Posted November 28, 2012 K-T boundry at Moscow Landing, Tombigbee River, Sumter County, Alabama. Mid-Maastrichtian Prarie Bluff Fomation (Chalk) and Mid-Danian Clayton Formation. "A problem solved is a problem caused"--Karl Pilkington "I was dead for millions of years before I was born and it never inconvenienced me a bit." -- Mark Twain Link to comment Share on other sites More sharing options...
Missourian Posted November 28, 2012 Author Share Posted November 28, 2012 Can I ask that people state whether there is an unconformity at their boundary, if they know it? For instance, Missourian, I believe there is one between the Vishnu and Tapeats? Yes, both are definitely unconformities. The Precambrian termination is the granddaddy of all unconformities. It is often referred to as the "Great Unconformity". Technically, it is a nonconformity here where it overlies the Vishnu Schist. The pre-Pennsylvanian gap shown above is a major disconformity across the Midcontinent. In many spots, it is underlain by Devonian or Ordovician rocks. Context is critical. Link to comment Share on other sites More sharing options...
MikeR Posted November 29, 2012 Share Posted November 29, 2012 A definite unconformity. Maastrichtian Peedee Formation and Bartonian Castle Hayne Formation contact at the Martin-Marietta Rocky Point Quarry, Pender County, North Carolina circa 2002. 1 "A problem solved is a problem caused"--Karl Pilkington "I was dead for millions of years before I was born and it never inconvenienced me a bit." -- Mark Twain Link to comment Share on other sites More sharing options...
MikeR Posted November 29, 2012 Share Posted November 29, 2012 (edited) Another one. Piacenzian Yorktown Formation, Rushmere member where all of the weeds are growing sitting on top of Campanian Black Creek Group sediments on the Roanoke River, Halifax County, North Carolina. Edited November 29, 2012 by MikeR "A problem solved is a problem caused"--Karl Pilkington "I was dead for millions of years before I was born and it never inconvenienced me a bit." -- Mark Twain Link to comment Share on other sites More sharing options...
Wrangellian Posted November 30, 2012 Share Posted November 30, 2012 (edited) Interesting... I'll have to think about where the bounds/contacts are in my area and get pix next time I'm out... weather has not been cooperating lately tho'. During a college field trip we were shown a spot in a roadcut near the college where a scientist took core samples to find where the magnetic field flipped.. that sort of thing might be interesting to post as well? Edited November 30, 2012 by Wrangellian Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now