Sequence Stratigraphy and other topics (April 30 & May 2)

There is no better resource for sequence stratigraphy than the excellent on-line guide written by my colleague Steve Holland at the University of Georgia Stratigraphy Laboratory. The extensive sequence stratigraphy webpages at the University of South Carolina are also very good. They include animations and exercises. Who needs professors these days?

On the last class day of this course we traditionally cover topics of our choice. If we have time, we will talk about the Channeled Scablands of eastern Washington and related topics, including the famous jökulhlaups. There is a good story here as well about a persistent and ingenious geologist named J Harlen Bretz. We may finish the course by briefly covering biostratigraphy and chronostratigraphy. The sites I’ve found on the topic are either terribly dull or well below your highly-developed skills. There are many detailed pages as examples of chrono- and biostratigraphy, like this one on the new Ypresian/Lutetian boundary stratotype. Wikipedia has a useful page on magnetostratigraphy with links to various practical examples.

Remember that your Final Lab & Lecture Exam is Tuesday, May 7, 3:00 – 5:00 p.m.

New Oxford Conglomerate (Triassic) of York County, Pennsylvania. Collected by Dr. Shelley Judge. (Click to enlarge.)

Geology in the News –

When methane hydrates are in the news, it is rarely good. The warming of the Arctic with the epic thawing of permafrost, is already producing thermal feedback and massive expenses.

With new technology (and ideas), our concepts of the Earth’s interior have become more complex. The core-mantle interface is especially interesting. We may at last be learning about the origin of mantle plumes.

Check out this newly described carnivorous mammal larger than a polar bear. It is 22 million years old and African. The specialized teeth of Simbakubwa kutokaafrika are impressive.

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Tectonics and Sedimentation (April 23 & 25)

“Tectonics and Sedimentation” is a broad topic with few direct web references; we’ll start with a review on Tuesday. You may want to revisit Plate Tectonic theory with this primer on plate tectonics. An excellent (and very useful) website is that of Ron Blakey at Northern Arizona University. It contains superb maps for each period and excellent discussions of issues in tectonic sedimentology. Here is an excellent website from James Madison University on the Wilson Cycle (love that name). This will be useful when we discuss sediments produced under particular tectonic conditions. James Madison University also has a good summary site on sedimentary rocks.

We will also cover general stratigraphy, which will be in part a review. There is no better resource for sequence stratigraphy than the excellent on-line guide written by my colleague Steve Holland at the University of Georgia Stratigraphy Laboratory. The extensive sequence stratigraphy webpages at the University of South Carolina are also very good for our work next week. They include animations and exercises. Who needs professors these days?

Swan Peak Quartzite (Ordovician) exposed near Tony Grove Lake, Cache County, Utah. (Click to enlarge.)

Geology in the News –

Geological time scale showdown! This month it may be “officially” decided whether we’re now in a new geological time interval: the Anthropocene. The levels of controversy are delicious, from when the Anthropocene would start to whether we need a new term at all. Right now there is progress towards making 1950 the boundary year.

Was a fireball meteor which struck Earth in 2014 actually from outside our Solar System? This was not even thought a possibility a few years ago.

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Coal and Petroleum (April 16 & 18)

King Coal and Big Oil this week. Let’s start with the Wikipedia page on coal, which is very good. A visit to the World Coal Association page will give you a sense of the magnitude of coal production. Here are some evocative pictures from the coal industry. The coal industry in the USA is in serious decline.

Petroleum is remarkable stuff — so much energy packed into such a convenient fluid. You may want to visit the websites of the American Petroleum Institute and the U.S. Energy Information Agency to see just how dependent we are on the black gold. There are few topics in geology so politically volatile as petroleum. Of course petroleum is from life sources, but a debate continues among a very few.

Methane hydrates (also known as “methane clathrates”) are fascinating hydrocarbon deposits. The USGS reminds us that the methane contained in these ices is a greenhouse gas with considerable potential to warm the Earth’s atmosphere significantly and quickly. This certainly has happened in the past, possibly during the Paleocene-Eocene Thermal Maximum. There is now even an experimental methane hydrate production well in the permafrost of the Far North. Here’s a video of the Alvin mucking about with a methane hydrate deposit.

Cannel coal from the Upper Carboniferous of northeastern Ohio.

Geology in the News –

Here’s the best account I’ve found describing the marvelous image of a black hole revealed last week. An historical moment. If you’re not impressed it is because you don’t understand the gravity of the situation.

And then there’s a new extinct hominin in the Philippines! Homo luzonensis lived between 50,000 and 67,000 years ago on a Philippine island. Let”s watch how this story develops.

Finally, and it sounds now so prosaic, there are some newly discovered dinosaur skin impressions. Early Cretaceous of South Korea.

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Siliceous Sediments, Ironstones, and Phosphates (April 9 & 11)

Chert is not a big topic on the Web. Wikipedia’s article on chert is scholarly but short. An amateur has put together a very detailed page on flint and chert (and what may or may not be the differences between the two). The most important ironstones are the banded iron formations (BIF) that form the bulk of Michigan’s iron industry. Wikipedia’s page on banded iron formations is accurate and well-sourced. Nothing very exciting, but note that BIF includes chert. Phosphorites are less common on the Web. At least we can bring in the “Phosphorite War” in Estonia! Oh, and Peak Phosphorus is another future calamity you can now worry about. Otherwise I must say this is a rather boring week for our webpages. Good time to work on your research paper.

Remember that Essay #2 is due on Thursday, April 11, at 7:30 am in your Dropbox folder.

Banded Iron Formation specimen from Upper Michigan. (Click to enlarge.)

Geology in the News –

For the extraordinary story about the end-Cretaceous extinction deposits recently described in North Dakota, first read this BBC account, which is typical of the hundreds of news stories about the finds. Next read this long but entertaining story in The New Yorker. Finally for a more mixed (and realistic) appraisal, read this news article in the journal Science. It is becoming a fascinating scientific and cultural narrative. [Update: Another  perspective on this story.]

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Evaporites and the Environments in Which They Form (April 2 & 4)

For evaporites, there is nothing quite like a virtual field trip to a sabkha, courtesy of Dr. Wikipedia. The Wikipedia page on evaporites is another good gateway of information and links. I’ve worked with the evaporites in the Purbeck Formation (Jurassic-Cretaceous) of southern England. We can take another virtual field trip to the Great Salt Lake in Utah to see modern evaporites forming. (I was there three years ago and will show plenty of photos in class.) You can also take a short trip to Badwater in Death Valley — the lowest point in North America — where salts of various kinds are forming from evaporation. (The Wooster Geologists visited Death Valley during a Spring Break trip.) The Dead Sea (Israel and Jordan) is a fascinating place for geology, ecology, economics and politics, as you can see in this short video and this recent visit by Melissa Torma and me. Did you know that during the Miocene the Mediterranean Sea became a vast evaporative basin? Of course you didn’t — this is why you need me!

Dr. Ian West, who, as we Americans often say, is “very British,” has a comprehensive page of sedimentary geology web resources, including bibliographies. It may be useful for your research paper. If you want to see all the ways to get hurt on a geological field trip, check out his safety page.

Just for your entertainment, here is utter nonsense with a sedimentological basis: “The Artistic Technology of the Ancients: Osijela Hill in the Bosnian Pyramid Complex“. It is a bottomless pit of senseless speculation grounded on complete ignorance of sedimentary structures and stratigraphy.

Your second lecture exam is on Thursday, April 4, and it covers everything we have done through Tuesday, April 2. Here is a copy of the Spring 2017 Sed Strat test.

Teepee structure in a modern halite deposit; Dead Sea, Israel. Note a Wooster IS student for scale! (Click to enlarge.)

Geology in the News –

There has been a fantastic discovery of soft-bodied fossils in the Cambrian of China. The Qingjiang Biota rivals the Burgess Shale Fauna — at least half of the species are unknown to science. Bob Gaines of Pomona College is one of the co-authors on the first of what will be many papers.

Here’s a bit from the world of nonsense: “Why do flat-earth believers still exist?“. The most archaic and ridiculous ideas about our Universe are increasing in popularity, despite unprecedented access to real science. Explore why.

Here’s a story about dinosaur reconstructions (as in museums) catching up with the science.

Finally, check out the departmental blog describing our recent field research in the Jurassic of southwestern Utah. Spring Break is a great time for geology out West.

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Continental Margins and Deep Marine Systems (March 26 & 28)

We will spend some of your first week back from Spring Break finishing carbonates and their depositional environments (see previous links). We will then move into deeper marine systems and return for a short time to siliciclastic sediments (especially clays). Start with an absolutely beautiful (and large) color physiographic map of the oceans and continents, courtesy of your federal government. This would make a nice desktop image, suitably slimmed down. Here is another NOAA map showing the ocean floors only, again in vivid colors. Makes you proud to be a geologist. Move on to a sediment-thickness map (a work-in-progress from NOAA) and we can begin our week’s material. (Be ready to explain the thickness patterns.) The NASA SeaWIFS Project has stunning color satellite images of the oceans. (I like the design-your-own-globe part.) The world’s greatest source of information about deep-sea sediments is housed in the Lamont-Doherty Earth Observatory Division of Marine Geology and Geophysics. The Monterey Bay Aquarium Research Institute (MBARI) also does fantastic (and photogenic) deepsea work.

Here is a turbidity current video we will use in class; here’s another of a geologist explaining turbidites. Here is a diagram of a Bouma Sequence.

Did you know that the director, producer and explorer James Cameron made an extraordinary dive to the deepest waters on Earth? Check out the Deepsea Challenge website. I am very impressed with his torpedo-like submarine. This site has a nice section on the geology of the Mariana Trench. Of course, the biology is way cool too.

Your second lecture exam is on Thursday, April 4, and it covers everything we have done through Tuesday, April 2. Here is a copy of the Spring 2017 Sed Strat test.

Oxford Clay (Jurassic) exposed near Weymouth, England. (Click to enlarge.)

Geology in the News –

Here’s an interesting article speculating on how the dinosaurs would have fared without the asteroid impact. It turns out to be a complex statistical problem to solve. Of course, we mean the non-avian dinosaurs!

At least one Cretaceous shark (Squalicorax) ate one pterosaur (Pteranodon) based on a chewed-up wing bone. Must have been quite a scene at the time!

A new reconstruction of Tyrannosaurus rex is now on display at the American Museum of Natural History, and it is a feathery masterpiece. Not without controversy, of course!

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Carbonate Systems (March 5 & 7)

Carbonate sediments are gifts of the sea, so let’s go there first. Maybe you’d like to stay in this nice little resort in Belize? NOAA has a wonderful website called “The Coral Kingdom” with many online photographs of reef animals and plants. Their National Underwater Research Program photo album is also very good. For that matter, visit the NOAA oceans page for links to extraordinary marine resources and images. The health of coral reefs is a great concern. Here’s a detailed USGS website which explores the hypothesis that airborne Saharan dust is devastating Atlantic and Caribbean coral systems. Let’s not forget all those wonderful ancient reefs as well. Everyone will want to visit “Jurassic Reef Park“. Apply your language skills to these reef pages in German.

Here’s a taste of our field research last summer in the Middle Jurassic carbonates of Utah. Evan and Anna will be there soon!

Remember: Osgood Lecture on March 5, 7:30 pm, Lean Lecture Room (required) — “Invasive species, mass extinctions, and biotic radiations: lessons for today from oceans of the past” (Dr. Alycia Stigall, Ohio University).

Don’t forget your first lab test this week (Thursday). It is entirely devoted to siliciclastic rocks.

I hope you enjoy your long Spring Break!

Pisolites in the Conococheague Limestone (Upper Cambrian) of eastern Pennsylvania. (Click to enlarge.)

Geology in the News –

Climate change is both threatening archaeological (and geological) sites and revealing new artifacts and rocks. I suppose we can conclude that there are some silver linings as the ice relentlessly retreats.

Nice images of dry river beds on Mars, showing direct evidence for its watery past. (We, of course, call them wadis.) Where all that water went is a mystery.

Did you know that two-thirds of known meteorites have been collected in Antarctica? You’ll see why after reading this recent account of a British expedition.

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Carbonate Petrology (February 26 & 28)

It is with carbonate rocks that we see most distinctly that life is a geological process (trademarked, all rights reserved). The large majority of carbonate sediments are directly derived from living systems, and as such they are excellent indicators of past depositional environments. You will want to see these ultimate mineralogy pages for calcite, aragonite and dolomite. For simple introductions to carbonate sedimentology, visit the excellent carbonate pages from the Texas Bureau of Economic Geology. (They have nice online review questions!) As we approach more detailed carbonate topics, please visit the Wikipedia page on carbonate biomineralization, and this one on carbonate classification. There are some  good photomicrographs of carbonate rocks (and others) on this Oxford University webpage. And we must take a field trip to the Bahamas someday, but for now we have to do it virtually!

Coral sand from a beach on Aruba. (Click to enlarge.)

Geology in the News –

A newly discovered sauropod dinosaur in Argentina has extended neural spines, headlined as having a “bony Mohawk”. These spines were not weapons and may have had sexual selection value.

Melting glaciers in Greenland (bad news) are forming new deposits of sand (good news). I had no idea plain old quartz sand had such economic value. There are even sand-based mafia!

A gorgeous multi-layered, multi-spectral view of the Whirlpool Galaxy, courtesy of the venerable Hubble Space Telescope.

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Coastal & Shallow Sea Systems (February 19 & 21)

The USGS Coastal and Marine Geology Program maintains an extensive set of webpages. One of the most interesting for coastal geology covers the coastal damage produced by Hurricane Katrina in 2005, including impressive lidar images of pre- and post-hurricane coastal changes in three dimensions. El Niño is a climatic state which greatly affects coastal processes, especially on the west coast of the USA; on this topic you might want to see the Tropical Atmosphere Ocean website from the National Oceanographic and Atmospheric Administration (NOAA). You may enjoy looking at surf webcams to escape this cold Ohio winter! Here’s a “documentary” on waves and surfing.

We now know much about tsunamis and their often tragic effects. The Tsunami Information Website from NOAA has tsunami graphics and simulations. The PBS webpage on tsunamis has graphic stories and a small animation. You will want to read about the 2011 earthquake and tsunami in Japan.

When it comes to understanding the difference between spring and neap tides, you can’t beat this simple animation by James Irwin which I will use in class (if I can just figure out how to slow it down). There is a nice barrier island panorama and other images from the coast of North Carolina on this website from Steve White. You can also look at some beach profile animations on Long Island produced by geologists at Hofstra University.

Sediment plume from DeGeerladen, south shore of Isfjorden, Svalbard, Norway. (Click image for larger view.)

Geology in the News –

The insect apocalypse is upon us. We are in the midst of a terrible Mass Extinction equivalent to some of the worst we’ve seen in the fossil record. Insect losses signal ecosystem collapse. Yikes.

Hummingbirds, little sweet hummingbirds, have a fantastic evolutionary history of violent competition with their elaborate beaks. This is a well-written and illustrated account in the New York Times.

It’s not very often we see evidence of cancer in the fossil record. Recently a leg bone of one of the earliest turtles (Triassic) was found to show signs of bone cancer. Most unusual.

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Deltaic and Estuarine Systems (February 12 & 14)

With deltas and estuaries we can apply all those principles of aquatic sedimentation we have learned, and add a few more. The Danube Delta looks like an interesting place to visit, even if it is under siege from pollution and over-fishing. The Niger Delta is a much more socially-troubled place because it is so rich in petroleum. The Ganges Delta is gorgeous from space. Has there ever been a more perfect delta than that of the Nile River? (An image from the European Space Agency.) This small site from the USGS on the San Francisco Bay and Delta region is interesting for both the deltaic and estuarine issues. We cannot, of course, forget America’s greatest delta, that of the Mighty Mississip. For an introduction to Mississippi River Delta geological issues, click into the Coastal Studies Institute pages from Louisiana State University. There is also a series of animations showing land losses along the Louisiana coast. Do you know why this erosion is occurring? The USGS has a large set of wonderful satellite images of the Pearl River Delta in southern China. How about this delta on Mars? It will be the site of a 2020 rover mission. Here is the excellent summary Wikipedia page on deltas.

Finally, Test #1 will be on Thursday, February 14. As a sample of what to expect, here is a pdf of the 2017 first Sed Strat test. We will not have covered all the same topics, so some questions in that test are on material we may not do this year.

Cross-bedding and scour in the Logan Formation (Lower Carboniferous) of Jackson County, Ohio.

Geology in the News –

Great images of “ice dust” dunes on the surface of Mars. Mars has a fascinating geological history still being worked out.

Later this month the Japanese spacecraft Hayabusa 2 will attempt to collect a sample from the asteroid Ryugu and return it to Earth. Fantastic!

During last month’s impressive lunar eclipse, a meteorite the size of a basketball struck the Moon’s surface. It was recorded by photographers by chance.What were the odds?

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