Cyclostratigraphic correlation of Middle Pennsylvanian Milankovitch Band eustatic cycles between southeast Arizona and the Midcontinent

Conference · Mon Feb 01 00:00:00 EST 1993 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5888395

Connolly, W M ^[1]

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1. Texas A and M Univ., College Station, TX (United States). Dept. of Geology

The cyclic pattern of deposition of the Horquilla Limestone of SE Arizona resulted from glacio-eustatic fluctuations with average periodicities (4th Order) of 152--380 ka, depending upon the time scale employed. The depositional surface fluctuated from subaerial to below the depth of autochthonous carbonate production, on the order of 60--100+ m for the larger cycles. Cyclostratigraphic correlations, within the best available biostratigraphic framework, have been established between sections in the predominantly carbonate Pedregosa and the predominantly clastic Western Interior basins, a distance of [approximately]1,500 km. Desmoinesian - lower Missourian cycles were correlated on the basis of flooding surfaces. The correlations emphasize the eustatic component of relative sea-level fluctuations in widely spaced basins with different depositional settings. The stratigraphic distribution of 71 species of Desmoinesian fusulinids was evaluated to corroborate the cyclostratigraphic correlations and develop a provisional zonation of the Desmoinesian Stage. High resolution interbasinal correlations have the potential to more accurately evaluate the temporal distribution and biogeographic dispersal of biostratigraphically useful taxa from basin to basin. Cyclostratigraphy may be the best way to accurately locate stage boundaries in distant basins with poor biostratigraphic control near the boundary interval, e.g., the Desmoinesian - Missourian boundary has been problematic in SE Arizona; based on cyclostratigraphic correlations, the revised position is 18--36 m lower than previous estimates'. Other applications include the refinement of eustasy curves, the inference of undetected cycles, and times slice analysis of paleoclimatic gradients and long term climate change (Cecil, 1990).

• OSTI ID: 5888395
• Report Number(s): CONF-9303212-; CODEN: GAAPBC
• Journal Information: Geological Society of America, Abstracts with Programs; (United States), Vol. 25:1; Conference: 27. annual Geological Society of America (GSA) South-Central Section meeting, Fort Worth, TX (United States), 15-16 Mar 1993; ISSN 0016-7592
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
ARIZONA
GEOLOGIC FORMATIONS
AGE ESTIMATION
PALEONTOLOGY
STRATIGRAPHY
DEPOSITION
FORAMINIFERA
FOSSILS
GEOLOGIC HISTORY
LIMESTONE
SEA LEVEL
SEDIMENTARY BASINS
VARIATIONS
ANIMALS
CARBONATE ROCKS
DEVELOPED COUNTRIES
GEOLOGIC STRUCTURES
GEOLOGY
INVERTEBRATES
LEVELS
MICROORGANISMS
NORTH AMERICA
PROTOZOA
ROCKS
SARCODINA
SEDIMENTARY ROCKS
USA
580000* - Geosciences