Sunday, March 29, 2020

George Washington's dolphins, and other NPS paleontology news

Here are a few recent items from the world of National Park Service paleontology:

Fossil Dolphins at George Washington Birthplace National Monument

You may remember from a couple of months ago the announcement of shark fossils from within the cave system of Mammoth Cave National Park, embedded in the Mississippian-aged rocks which host the caves. Here's another announcement of a marine nature, this time coming from George Washington Birthplace National Monument in eastern Virginia. At this park, dolphin fossils including two skulls were recently excavated from the Miocene-aged Calvert Formation bluffs along the Potomac. I'm particularly proud and pleased about this news, because I have been going to GEWA annually since 2014 to conduct monitoring of fossil resources. (I am also jealous because I wasn't available to participate!) There are two things going on here that threaten fossil resources: the Potomac can rather effectively batter the poorly lithified Calvert Formation bluffs when it gets churning; and there has been a long-time culture of collecting, which we've been trying to change.

March 2015, on part of the Potomac shore.

November 2019, somewhere close to the same place as the previous photo. The colors seem to be a seasonal thing (the colorful surfaces are scrubbed off during winter storms). Note the trees looming above.

When you're at a park, remember to leave the fossils where they are. Tell park staff if you come across something interesting. Maybe another dolphin will turn up!

Park Paleontology News, spring 2020

A couple of years ago we resumed the Park Paleontology newsletter as a collection of short online articles, published in the spring and fall. This venue gives us a chance to put out short pieces on our various projects, covering a variety of aspects of NPS paleontology from a range of viewpoints. The spring 2020 collection was recently made public and includes the following:

Feel free to also check out the back issues from the past few years, too!

Grand Canyon NP and Chaco Culture NHP virtual museums

One of our favorite methods of documenting fossils is through the use of photogrammetry to create 3D models. The basic concept is that you take a number of overlapping photos of something and then use dedicated software to stitch the photos into a digital 3D model. (This can also be used to print tangible 3D models as well.) Our interest started with documenting fossil vertebrate tracks; they don't always lend themselves to collecting (size of track surface, fragility, tracks being part of the scenery) and casting can damage them. Led by crack photogrammetry specialist Jack Wood, we've since expanded to a wide variety of fossils. We've recently made two collections of photogrammetric models available for viewing. One set captures examples of the wide variety of fossil organisms found at Grand Canyon National Park. The other, for Chaco Culture National Historical Park, is focused on the Western Interior Seaway.

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