Permian/Triassic Transition

CP1

CP1 conglomerate

DH1

DH1 breccia

Just a few pics to ponder as the details are yet to be worked out.

Who's Collecting Crittenden Springs?

Jim Jenks is writing a paper on the Early Triassic ammonoids he has collected over the years at the Crittenden Springs locality north of Montello, Nevada. He went out a few weeks ago to take some photos of the beds he collected and found that someone has been out there recently. Large excavations and partially collected fossils is what he found.

One of the large holes found


A large Churkites noblei partially collected (notice the saw cut)

Another large hole where the beds were exposed. Jim says excavations like this have occurred in several places.

Complete fossiliferous bed shown here, Jim exposed these for a photo in his paper, he says quite a bit has been removed from this site too.

The collecting area is on BLM and Winecup-Gambel Ranch property. It would sure be nice to know who has been collecting here, whether it is someone from an institution or commercial collectors. This seems to be a larger excavation than someone who is digging for reasonable and/or personal use would need to dig.

Early Middle Ordovician Cephalopods

I went with Dan and his Paleo Class out into Utah's West Desert. We collected some trilobites from the Cambrian Wheeler Shale, some brachiopods from the Permian Gerster Limestone, and then some fossils from the Ordovician Juab Limestone and Kanosh Shale.

The first photo is a Tarphycerid from the Juab Limestone, the second, a large Endocerid in a block of limestone from the Kanosh Shale.

Just a note on the advantages of taking two vehicles into the desert, if the battery goes dead on one, you can take the other into town to get some jumper cables. Of course if one would have had the cables in the first place there would have been no need for the run to town. But without the other vehicle it would have been a nice 30 mile hike, or at least a good long wait for someone to happen by.
I would also like to thank the truck driver at the Border Inn who gladly gave up a spare set of jumper cables, he wouldn't take anything for them, said someone had helped him earlier so he was just passing it on; someone has a good deed coming.

Dan's Paleo class on the slopes of Fossil Mountain,
L-R Mike, Patty, Connie, Dan, Kevin and Salem

MC Anasibirites Beds

Permian on the left, Black Dragon (Moenkopi red beds on left), Thaynes and then more redbeds on right
(possibly Chinle conglomerate capping hills on right)

?Hemiprionites, Anasibirites and Wasatchites

Anasibirites beds (gray) in center, about 20-25cm thick, with small "body chamber beds" (15cm thick) below,
with high angle fault. Beds with Inyoites and Guodunites below, Thick 50-60cm brown bed.

Cool folding in basal beds of Thaynes Group.

Early Triassic Anasibirites Beds

The Anasibirites Beds in the Confusion Range (above) comprise approximately 30 cm of limestone packed with cephalopod shells. On a recent two week trip collecting fossils from a few new outcrops and a couple of classic ones, I noticed how similar they all are.

From the Cephalopod Gulch locality, near Salt Lake City, where Mathews first described the Anasibirites fauna in the Western US (above). Another approximately 30 cm bed packed with the same fossils.

Smiths Phalen Ranch locality near Currie Nevada (above), another ~30 cm of limestone containing Anasibirites and Wasatchites.

A new locality (to me) in south west central Utah, where beds containing the Anasibirites fauna also occur. This locality needs a little more collecting to verify the thickness and content of the beds, but they seem to be much the same as the others.

Localities to the east, like the Pahvant Range, San Rafael Swell and near Cedar City have the Anasibirites fauna though not as abundant as those to the north and west. Other localities like Crittenden Springs, Nevada, where Anasibirites and other Prionitids occur in lenses above the Meekoceras beds and a locality in Southeastern Idaho (Jim Jenks pers. com.), add to the data.

All these beds record a short time interval right after an extinction event near the end of the Smithian Stage of the Early Triassic.

Uintacrinus and Desmoscaphites bassleri

Uintacrinus from the Mancos Shale

a small fragment of Desmoscaphites bassleri

These fossils were found by Rod Scheetz (BYU Museum of Paleontology) in the Mancos Shale southeast of Green River. The small fragment he found closely matchs the one I found (see Aug. 12, 2009 post). I am now quite sure they are D. bassleri, and the small Scaphites is S. leei, from the Latest Santonian. D. bassleri has been found in the Upper Emery Sandstone northwest of Price and Northwest of Green River, so the Lower Emery Sandstone or it's equivalents are probably not present south and east of Green River as the fossils I found were in the lowest concretions above the Scaphites depressus (Latest Coniacian) beds.

REF:
Landman N. H. and Cobban W. A., 2007, Redescription of the Late Cretaceous (late Santonian) ammonite Desmoscaphites bassleri Reeside, 1927, from the Western Interior of North America. University of Wyoming, Rocky Mountain Geology, v.42, no.2, p.67-94

Spathian? Ammonoids

Small ammonoids and orthoconic nautiloids found in a gray limestone concretion. Probably from the Spathian part of the Formation

Jack Rabbit

Earthquake damage in Wells, Nevada, waiting to be repaired?

The Ranch, in the distance, and what outcrops there are in the foreground.

Outcrops of Smithian rocks were not found on this trip :(

vermiformis? Beds

a small Scaphites from low in the ?Lower Emery SS beds of the Mancos Shale east of Green River.

Body chamber from Clioscaphites ?vermiformis. These seem to have a lot more ribs than typical C. vermiformis.

Sinbad Member Southern San Rafael Swell

Hondoo Arch. Limestone of the Jurassic Carmel Formation holding it up above the Navajo Sandstone, Kayenta and Wingate cliffs below, Varicolored Chinle below, and the upper part of the Moenkopi at the base.

Yellowish Sinbad Limestone on the other side of a fault, the gray fossiliferous base seen below the upper dolomitic beds.

It is hard to separate in this view, the Sinbad is in the middle, between red beds.

Gray beds on both side of the canyon

Sinbad Member near it's Type locality

Sinbad Formation of the Thaynes Group capping mesa, Black Dragon Formation of the Moenkopi Group just below (oil bleached in this area of the San Rafael Swell) and the ?Coconino/BlackBox Dolomite in foreground. One of the many waterpockets visible in the wash.

A tadpole in one of the waterpockets, probably a Spadefoot toad

The northern exposure of the Sinbad. Butte in background made up of Wingate Sandstone and the Chinle Formation.

One of the very poorly preserved ammonoids found in the Sinbad.

8ISCPP

8th International Symposium
Cephalopods - Present and Past
2010 @ Dijon, France
August 30th to September 3rd

I better start getting my poster ready

Critters that distract you from fossil hunting

Dan and Catherine playing with a Striped Whipsnake at DH

Mormon Crickets were quite common at DV

Not shown are all the lizards and tarantulas that were not photographed because I was to busy watching them.

Tentacles/Arms/Suckers

It's alive! I wonder what an ammonoids arm looked like?
The Enteroctopus dolfleini at the Steinhart Aquarium in the California Academy of Science
San Francisco, Ca.

Scaphitoid

Scaphitoid Cephalopod, Yezoites, possibly a new species.

A canyon cut through the Ferron Sandstone

Mancos Shale

End of April Field Trips

Lara and Holly at DV1

A nice view of DV2

Don't take my water

Sunrise at the Border Inn, Baker, Nevada.
The top of Notch Peak just visible below the "SLOTS" sign.
I lost all of $5 at them one armed bandits

Jim, Jean Guex, Viorel Atudorei, at Cowboy Pass (CP1)

April Field Trip

Camp in the Wheeler Amphitheater.
No ammonoids on this trip so this is the only pic I took.

Change

On March 30 Obama signed the Omnibus Public Land Management Act of 2009. Part of that is the Paleontological Resources Preservation Act, Specifically Title VI, Subtitle D (select text of legislation, then S.22.ES) . A provision to allow casual collecting is incorporated, but is very vague, otherwise a permit is required to collect any fossils on public land. Looks like change has come.

Polymorphism, Intraspecific Variation, Dimorphism, Covariation

A few terms that at first seem to be self explanatory. The first two seem to be interchangeable as do the last two. Reading a paper the other day, the title used one term but the body of the paper was filled with the other term. Could someone fill me in on the correct usage of these four terms, are they really all about the same. For years an ammonite was an ammonite until I found out that some were ammonoids, actually all are ammonoids and I was just using the wrong term for the whole group. It just took an explanation... like the one I am looking for now.
There are a few posts in this blog labeled with the term "Polymorphism", this term seems to have a deeper meaning than I was intending, so from now on this term will be replaced with "Intrapsecific variation", though not as snazzy sounding it probably is more in line with my intended meaning.

More from 3-21-09 Field Trip

Alex, in the center,
watching as I uncovered the big one.
He likes ammonites as much as I do.

this is the sign Alex had pinned to his pack. A future Paleontologist for sure?

Looking for Prionocyclus at Stop 2

Looking for Scaphites at Stop 1