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.
Permian on the left, Black Dragon (Moenkopi red beds on left), Thaynes and then more redbeds on right
?Hemiprionites, Anasibirites and Wasatchites
Anasibirites beds (gray) in center, about 20-25cm thick, with small "body chamber beds" (15cm thick) below,
Cool folding in basal beds of Thaynes Group.
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.
Uintacrinus from the Mancos Shale
a small fragment of Desmoscaphites bassleri
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.
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.
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 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.
