CARNIAN-NORIAN BIOCHRONOLOGY, CORRELATION AND 
BIOTIC EVENTS OF THE NONMARINE TRIASSIC OF NORTH 
AMERICA

	HUBER, Phillip, Department of Education, University of 	
		Bridgeport, Bridgeport, CT  06601
	LUCAS, Spencer G., New Mexico Museum of Natural History 
		and Science, 801 Mountain Rd., NW, Albuquerque, 
		NM  87104
	HUNT, Adrian P., Mesalands Dinosaur Museum, Mesa 	
		Technical College, Tucumcari, NM 88401

Strata of the Newark Supergroup and Chinle Group contain the most 
diverse, nonmarine biotas known from the Laurasian Triassic. Four 
land vertebrate faunachrons (lvf's) of Carnian-Norian age are 
recognized in each region that are temporally parallel and provide a 
substage-level, biostratigraphic framework through which trends of 
biotic change can be examined. Moderately diverse assemblages of 
Sanfordian (early Tuvalian) age are found in the Deep River, 
Richmond, Taylorsville and Fundy basins.  Age diagnostic taxa include  
Metoposaurus bakeri, a variety of thecodonts (cf. Scaphonyx, 
Longosuchus, Doswellia) and dicynodont Placerias, all  common to 
coeval, basal Chinle Group assemblages of Otis Chalkian age. The 
Conewagian lvf (late Tuvalian) guidefossil is the phytosaur Rutiodon 
carolinensis. Other taxa include metoposaurids (Buettneria perfecta), 
procolophonids, numerous archosaurs  (Euscolosuchus olseni, 
Desmatosuchus sp.),  moderately diverse dinosaurian and 
lepidosaurimorph (Tanytrachelos, Icarosaurus) components and 
numerous cynodonts (Microconodon, Dromotherium, 
Boreogomphodon).  Formations that contain Conewagian assemblages 
include the type Pekin and Cumnock (Chatham Gp.), Turkey Branch 
(Richmond basin), New Oxford (Gettysburg basin), and upper 
Stockton and Lockatong (Newark basin) Fms. Conewagian 
assemblages are correlative with the Chinle Group Adamanian lvf, as 
indicated by the shared distributions of Buettneria, Rutiodon, and 
Desmatosuchus.
	The early to middle Norian Neshanician lvf is defined by the 
stratigraphic range in the Newark basin (Warford through Perkasie 
Mbrs.) of the aetosaur Aetosaurus arcuatus. Other Neshanician 
assemblages (upper Chatham Gp., New Haven Arkose) include indet. 
labyrinthodonts, one or more rauisuchians, indet. phytosaurs, and a 
coelurosaur and are broadly correlative with the Chinle Group 
Reveultian lvf.  Late Norian-Rhaetian Cliftonian lvf assemblages 
contain the procolophonid Hypsognathus (upper Passaic, upper New 
Haven and possibly Wolfville Fms.) and are correlative with much 
more diverse, Apachean lvf assemblages from the uppermost Chinle 
Group.
	Independent calibration of vertebrate-based correlations is 
provided by developing magnetostratigraphies tied to the Newark 
cyclostratigraphic timescale.  These correlations indicate that most 
Newark strata dated as "middle Carnian" by palynomorphs actually are 
of late Carnian (Tuvalian) age, and that the hypothesized Newark 
"middle Carnian" extinction event is an artifact of poor, independent age 
control. The most significant biotic turnover occurs during the late 
Carnian and there is no evidence for terrestrial mass-extinctions at the 
Carnian-Norian boundary.     


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