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Great Basin National Park Park News National Park Service U.S. Department of the Interior The Midden The Resource Management Newsletter of Great Basin National Park Amazingly Successful Summer Paleontology Inventory During my first year after moving to GRBA, I had found a few good indications in the park’s backcountry. Also, park staff had recognized fossils in some of the remote drainages (see the Summer 2011 NPS Photo Midden article, “Significant index NPS Photo fossils found in park”). Some of the more than 1000 fossil In addition, geologic maps indicated specimens found this summer included these brachiopods, Orthambonites broad areas of rock outcrops within michaelis; Kanosh Shale, Ordovician the park where there was high An internal mold of a complete coiled Period. potential for fossils to be found. nautiloid cephalopod surprisingly similar to the living chambered nautilus. The dark By Gorden Bell, Supervisory These rocks are of the same age mass in the center is a bryozoan colony Environmental Protection Specialist and formations that are extremely that encrusted the shell after it fell to the and Paleontologist fossiliferous near Crystal Peak, Utah, seafloor; Lehman Formation, Ordovician Period. and in central Nevada. So, as the park If one were to judge the potential of is situated directly between those began to build an inventory of Great Basin National Park (GRBA) areas, it would seem likely that our paleontological resources heretofore to possess a significant amount of rocks might have the same kinds and unknown within the park. Over the paleontological resources based quantities of fossils. course of the summer we added 38 on available scientific literature, new paleontology localities to the it would not appear to be a good This past summer we were able to database, represented by 476 GPS bet. As part of my collateral test that possibility when we brought positions and more than 1000 fossil duties, I had been given the task in two Geoscientists-in-the Parks specimens. of first assessing the likelihood of interns (GIPs) through a program significant paleontological resources sponsored jointly by the NPS and So, what types of fossils are present being present within the park and the Geological Society of America in the park? Continued on Page 2 then searching for them if the results GeoCorps program. The two GIPs, appeared promising. Linda Sue Lassiter and Spencer Holmes, are enrolled in geology In This Issue My survey of the literature had degree programs at the University of turned up only one publication that Northern Arizona and California State Paleontology Inventory................1 identified fossil localities inside University - Chico, respectively. Rattlesnake Relocations.................4 the park boundaries. Another three Lehman Cave Restoration..............5 identified fewer than a half-dozen During an intense 12-week internship, 2012 Diptera BioBlitz.......................6 fossil localities in the southern these two intrepid students and I Forest Health.......................................8 Snake Range but outside of the park. covered approximately 600 hectares Johnson Lake Mine Recorded.....10 However, numerous publications (1500 acres) of the park, searching Fire Needed.....................................11 detailed exciting discoveries in the rock outcrops for fossils and using Remote Cameras.............................12 mountain ranges to the east, south, GPS units and cameras to document 2011 BioBlitz Update.....................14 and west of the park. what we found. Gradually, we Upcoming Events....................14 Winter 2012/2013 Issue 12 Volume 2 2012 Summer Paleoinventory Results (continued) Most of the fossils are animals organisms. We also spotted many Probably one of the most exciting and plants that lived in a marine types of molluscs, including some finds was a thick bed of corals at an environment in a relatively shallow clams, many species of marine elevation of almost 3350 m (11,000 sea that alternately covered and then snails, and plenty of straight ft), north of Granite Peak. About receded from this area many times nautiloids, which are cephalopods 470 million years ago during the over. Most are very old, spanning like squids and octopi but which Ordovician Period, living corals portions of the Cambrian and had a long conical external shell. may have covered the local sea Ordovician geologic periods from We did find one coiled nautiloid, floor like a patchwork blanket that about 510 to 470 million years ago. which does not appear to be much stretched for many kilometers. different than the chambered Geologists would call this type We found strange types of algae nautilus living in modern oceans of accumulation a “biostrome.” called receptaculitids that have today. While the bed we found would mineralized rod-shaped spicules not technically qualify as a reef forming an internal skeleton like because it only stood one to two that found in some sponges. One metes (three to six feet) above the type, Receptaculites, as shown in the seafloor, it nonetheless must have Summer 2011 issue of The Midden, functioned as reef-like habitat. The is shaped like a biscuit while another NPS Photo corals that grew in this biostrome, type, called Calathium, is conical Eofletcheria and Foerstephyllum, like an empty ice cream cone and are two of the three earliest forms often formed mounded colonies. The straight shell of a type of nautiloid of corals known in the fossil record. cephalopod, sometimes called an orthoceracone; Lehman Formation, Both are classified as members of We found plenty of trilobites, which Ordovician Period. a stem group known as tabulate are common in the surrounding corals. Corals would have to evolve areas, including a couple of tiny We were even lucky enough to pick blind forms called agnostids. up a single plate from an animal known as a chiton, a slug-shaped mollusc with a row of eight hard plates armoring its back. We found lots of stalked echinoderms, aka NPS Photo NPS Photo “sea lilies,” such as crinoids that stood well above the sea floor to This large trilobite tail is an undescribed catch food particles floating in the species of Cybelopsis (the quarter used water and cystoids that scooted Crowded and overgrown masses of the as scale is exactly an inch in diameter); coral, Eofletcheria, indicating a reefy Lehman Formation, Ordovician Period. around in the bottom muds to find type of habitat; Lehman Formation, food. Ordovician Period. We also found brachiopods, which much greater complexity and have bivalved shells. Some of these longevity before they could grow lived in muddy burrows and have into the massive shapes we know phosphatic shells, while others as true reefs. We were able to trace had calcium carbonate shells and one unbroken outcrop of this bed attached themselves to various NPS Photo of coral for a distance of about living animals or dead shells. We 370 m (1200 ft) where its edges located bryozoans, distantly related are interrupted by erosion or by to brachiopods but living in tiny faulting. We could pick it out again coral-like colonies that either grew A single plate from a cystid echinoderm, in nearby outcrops at about the probably Hadrocystis; Pogonip Group, independently or encrusted other Ordovician Period. Continued on Page 3 2 The Midden 2012 Summer Paleoinventory Results (continued) same horizon, suggesting it was indeed connected while growing. As it turns out, Eofletcheria has been reported as biostromal accumulations at about the same stratigraphic level in outcrops from Crystal Peak, in NPS Photo Utah all the way to the White Pine Range at the western edge of White Pine County in Nevada, a distance of more than 160 km (100 mi) today (map figure). The first vertebrate fossil from the park, a partial fin spine of an acanthodian fish Based on calculations of the amount tentatively identified as Nodocosta denisoni; Sevy Dolomite, Devonian Period. of geological extension that has As a final note, the occurrence of specimen is shown above and occurred during faulting in the Great Foerstephyllum at GBNP is only the is a fragmentary fin spine of an Basin, that distance would have been second record from Nevada – the acanthodian fish. It was tentatively approximately 100 km (60 mi) at the first being from the Ordovician rocks identified by Dr. David Elliot of time the coral was growing. Other of the Pioche area. Northern Arizona University as observations note that Eofletcheria Nodocosta denisoni. The specimen is found in float blocks at about the And last but not least, this summer was found on outcrops of the Sevy same stratigraphic level not far north we also found the first vertebrate Dolomite which is Early Devonian of Big Springs on the southern end fossil from the park! It is not much age and is about 405-400 million of the Snake Range. This suggests to look at and is only 13 mm (0.5 years old. Appropriately, the that the coral patch habitat might in) long, but some people place Devonian Period of geologic time is have originally grown in an east-west more significance on vertebrate also known as the “Age of Fishes.” trending tract at least 100 km (60 fossils than invertebrate fossils. Our mi) long and 16 km (10 mi) wide. So, in reflection, the amount and quality of fossil resources we found in such a short amount of time is amazing given so little indication in the scientific literature. This is due in large part to the efforts and dedication of our two GIPs, Linda Sue and Spencer. I want to extend a rousing round of thanks to them. It is also appaerent that GRBA contains a wealth of paleontological resources, but had simply been overlooked by researchers. After this past summer I am confident that we will make even more exciting discoveries next summer and that this paleontological inventory may very well spark a new era of geological and paleontological research at Great Basin National Distribution map of coral biostrome localities in the uppermost Lehman Formation Park.

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