K-Bentonites and Graptolite Biostratigraphy in the Middle Ordovician of New York State and Quebec: A New Chronostratigraphic Model

Palaios ◽  
1994 ◽  
Vol 9 (2) ◽  
pp. 124 ◽  
Author(s):  
Daniel Goldman ◽  
Charles E. Mitchell ◽  
Stig M. Bergstrom ◽  
John W. Delano ◽  
Steven Tice
Keyword(s):  
New York ◽  
New York State ◽  
York State ◽  
Middle Ordovician

Revision of the Oxford Formation (Arenig) of southeastern Ontario and northern New York State

1976 ◽  
Vol 13 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Ivor J. Bond ◽  
Robert G. Greggs
Keyword(s):  
New York ◽  
Quartz Sand ◽  
Sedimentary Environment ◽  
New York State ◽  
Total Thickness ◽  
Minimum Thickness ◽  
York State ◽  
Middle Ordovician ◽  
Lower Division ◽  
Lower Contact

The Oxford Dolomite of southeastern Ontario is considered to be equivalent to the Ogdensburg Dolomite of northern New York State. The Oxford Formation is redefined in terms of its lithology, distribution, thickness, sedimentary environment, and age.A series of representative sections can be correlated with wells drilled in southeastern Ontario. The formation rests disconformably upon the March Formation (Tremadocian) and is overlain disconformably by Middle Ordovician (Chazyan) sediments. The lower contact of the formation is widely exposed, but the upper contact is known only from boreholes.Lithologies are not distinctive; a lower division in which quartz sand is abundant and an upper division in which it is rare or absent can be recognized. The total thickness of the formation is not known; however, a minimum thickness of 605 ft (184.5 m) is present in a well near Williamsburg, Ontario. Conodont faunas indicate that the age of the Oxford is Lower Arenig and the disconformity at the base of the formation marks the base of the Arenig series in the Ottawa – St. Lawrence Lowlands.

The stratigraphic distribution of graptolites in the classic upper Middle Ordovician Utica Shale of New York State: an evolutionary succession or a response to relative sea-level change?

Paleobiology ◽  
1999 ◽  
Vol 25 (3) ◽  
pp. 273-294 ◽  
Author(s):  
Daniel Goldman ◽  
Charles E. Mitchell ◽  
Michael P. Joy
Keyword(s):  
New York ◽  
Sea Level ◽  
New York State ◽  
Sea Level Change ◽  
Relative Sea Level ◽  
York State ◽  
Middle Ordovician ◽  
Faunal Turnover ◽  
Level Change ◽  
Relative Abundances

The stratigraphic distribution of graptoloid species within the upper Middle Ordovician strata of New York State represents a complex pattern of origination, extinction, faunal migration, and fluctuating relative abundances. In particular, the observed patterns of species turnover at graptolite biozone boundaries are apparently strongly correlated with lithofacies, sampling strategies, and the depositional effects of relative sea-level change.Vertical facies changes that occur within third-order depositional sequences and fourth- or fifth-order parasequences are mirrored by changes in the graptoloid faunal composition. Large-scale faunal turnovers at biozone boundaries tend to occur either at sequence boundaries or at flooding surfaces within sequences (e.g., the base of Highstand System Tracts). The base of theCorynoides americanusandClimacograptus (D.) spiniferusZones coincide with major onlap events, and theOrthograptus ruedemanniZone fauna appears just below a Lowstand Systems Tract. Within individual biozones, smaller-scale changes such as the fluctuating relative abundances of graptoloid species coincide with higher-order parasequence cyclicity. These distribution patterns resemble recent computer-generated models for the sequence stratigraphic distribution of hypothetical taxa.By combining good biogeographic control with a detailed sampling program, we are able to see through the patterns attributable to depositional cyclicity and identify the different components of faunal turnover (migration, speciation, and extinction).

scholarly journals Structural Elements and Neotectonics of Prince Edward County, Southern Ontario

2007 ◽  
Vol 47 (3) ◽  
pp. 303-312 ◽  
Author(s):  
Gail H. McFall
Keyword(s):  
New York ◽  
New York State ◽  
Lake Ontario ◽  
Structural Features ◽  
Structural Elements ◽  
Southern Ontario ◽  
York State ◽  
Salmon River ◽  
Middle Ordovician ◽  
Prince Edward County

ABSTRACT The seismically active Clarendon-Linden Fault of western New York State appears to connect with the Salmon River Fault and possibly with the Picton Fault, both of which cut through Prince Edward County, southern Ontario. Bedrock exposures display a variety of structural features including faults, fractures, and pop-ups which indicate that the region has been subjected to repeated tectonism since the Middle Ordovician. Thus, despite the general perception that Prince Edward County and the rest of the Lake Ontario region is one of low seismic potential, geological and geophysical data suggest otherwise.

Lower Ordovician (Ibexian) trilobites from the Tribes Hill Formation, central Mohawk Valley, New York State

1993 ◽  
Vol 30 (8) ◽  
pp. 1618-1633 ◽  
Author(s):  
Stephen R. Westrop ◽  
Leanne A. Knox ◽  
Ed Landing
Keyword(s):  
New York ◽  
New York State ◽  
East Central ◽  
York State ◽  
Middle Ordovician ◽  
Mohawk Valley ◽  
City Formation ◽  
Late Cambrian ◽  
Lower Ordovician ◽  
Central New York

The Early Ordovician Tribes Hill Formation of east-central New York State is a sequence of peritidal to subtidal carbonates and minor shales that rests disconformably on Late Cambrian carbonates and is, in turn, succeeded disconformably by Middle Ordovician strata. More than 800 trilobites from 24 collections are assigned to six species: Bellefontia gyracantha (Raymond), Clelandia parabola (Cleland), Hystricurus ellipticus (Cleland), Hystricurus cf. Hystricurus oculilunatus Ross, Symphysurina convexa (Cleland), and Symphysurina cf. Symphysurina woosteri Ulrich. Two distinct biofacies are present: the Bellefontia Biofacies in subtidal shales with thin, storm-generated bioclastic interbeds, and the Gastropod–rostroconch Biofacies in shallow, carbonate bank lithofacies. The trilobites of the Tribes Hill Formation are assigned to a single, informal biostratigraphic unit, the Clelandia parabola Fauna, which is correlative with trilobite Zone B of the Garden City Formation of Utah and with the Bellefontia franklinense Subzone of the McKenzie Hill Formation of Oklahoma.

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