Apatite fission-track thermochronology of the central and southern Appalachian Basin

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6643117

Roden, M K

Samples were collected in west to east transects across the Appalachian Basin of Pennsylvania, Maryland, West Virginia, and Virginia. These samples locations were chosen to test the concept of increasing paleotemperature due to increasing burial from west to east across the Appalachian Basin and to detect any thermal anomalies that exist. Calculated time-temperature (tT) paths based on apatite fission-track apparent ages and confined track length distributions for samples from this study indicate that both the Pennsylvania and southern Appalachian had complex uplift and cooling histories. In Pennsylvania, the Tioga and Kalkberg ash bed samples from central Pennsylvania yield modelled tT paths that indicate early post-Alleghanian (285-270 Ma) cooling with uplift estimated at beginning at {approx}251 {plus minus} 25 Ma. Samples from the western Allegheny Plateau and Allegheny Front contain apatites which have reset to give fission-track ages and track lengths consistent with tT histories beginning at <200 Ma. In northeastern Pennsylvania on the Allegheny Plateau, the modelled tT paths show rapid cooling from temperatures in the range of 110{degree}-120{degree} C at 170-160 Ma. In the southern Appalachian Basin, calculated tT paths indicate that uplift in the northern section was immediately post-Alleghanian folding with uplift beginning first in the northwestern section on the Cumberland Plateau at {approx}226 {plus minus} 23 Ma and progressing to the eastern Valley and Ridge Province of Virginia at {approx}119 {plus minus} 12 Ma. The samples from southwestern Virginia yield a mean apatite fission-track apparent age of 175 {plus minus} 11 Ma which may be the result of a higher heat flow, higher paleogeothermal gradient during the Upper Jurassic-Early Cretaceous extension along the Atlantic Coast.

• Research Organization: Rensselaer Polytechnic Inst., Troy, NY (USA)
• OSTI ID: 6643117
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
AGE ESTIMATION
APATITES
APPALACHIAN BASIN
COOLING
DEVONIAN PERIOD
FEDERAL REGION III
FISSION TRACKS
GEOLOGIC AGES
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
GEOTHERMAL GRADIENTS
GROUND UPLIFT
MARYLAND
MINERALS
NORTH AMERICA
PALEOCLIMATOLOGY
PALEONTOLOGY
PALEOTEMPERATURE
PALEOZOIC ERA
PARTICLE TRACKS
PENNSYLVANIA
PHOSPHATE MINERALS
SEDIMENTARY BASINS
TECTONICS
TEMPERATURE DEPENDENCE
TEMPERATURE GRADIENTS
TIME DEPENDENCE
USA
VIRGINIA
WEST VIRGINIA