PALYNOFLORAL DIVERSITY AND PROVINCIALITY IN THE 
LATE TRIASSIC NEWARK SUPERGROUP

	FOWELL, S. J., OLSEN, P.E., and KENT, D.V., Lamont-
		Doherty Earth Observatory of Columbia University, 
		Palisades, NY 10964

During the Late Triassic, rift basin lakes of the Newark Supergroup 
spanned more than 10° of paleolatitude and straddled a paleoclimatic 
boundary.  Basins at the southern end of the supergoup were subject 
to a humid equatorial climate, whereas the northern basins occupied a 
sub-equatorial arid zone.  Such variations in paleolatitude and 
paleoclimate among tectonically similar basins render the Newark 
Supergroup ideal for examining the relationship between paleoclimate 
and Triassic palynomorph assemblage composition and diversity. 
	The cyclostratigraphy and magnetic reversal stratigraphy of 
continuous cores from the Late Triassic portion of the Newark basin 
has established a rigorous temporal and paleogeographic framework 
that permits high-resolution correlation of palynologically productive 
units from basins in the United States, Canada, and Morocco.  
Correlation of 400 kyr cycles between southern and northern Newark 
Supergroup basins allows comparison of palynomorph assemblages 
from different paleolatitudes during four time slices: the Carnian and 
Norian of the Taylorsville, Newark, and Argana basins; the Rhaetian 
of the Culpeper and Newark basins; and the Triassic/Jurassic 
boundary of the Culpeper, Newark, Argana, and Fundy basins.  
Preliminary results indicate that percentages of monosaccate and 
bisaccate genera increased over 7° of paleolatitude from the 
Taylorsville basin to the Fundy basin.  In addition, the average size of 
widely distributed species decreases from south to north, suggesting 
that size reduction may be an adaptation for arid environments.  The 
generic diversity within and between separate basins is currently 
being determined in order to assess the significance of variations in 
assemblage composition along the paleolatitudinal/paleoclimatic 
gradient. 
	Despite changes in palynofloral composition between the 
southern and northern basins, a decline in species diversity is 
observed at the Triassic/Jurassic boundary throughout the Newark 
Supergroup.  This pandemic extinction of Late Triassic species 
suggests that the low diversity of early Jurassic palynofloras was the 
result of overarching environmental changes that superseded regional 
paleoclimatic boundaries.