Paleomagnetic dating of liesegang bands

Conference · Tue Jan 01 04:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:6644299

Cochran, K A; Elmore, R

Paleomagnetic analysis, in conjunction with petrographic studies, was used to date the formation of hematite liesegang bands in the Ordovician Upper Arbuckle Group in southern Oklahoma. The hematite bands form symmetrical patterns on both sides of calcite-filled fractures in dolomite beds. The bands decrease in abundance and become more diffuse away from the fractures. Dedolomite is common near the fractures. Samples from distinctly banded dolomite near the fractures contain a relatively strong chemical remanent magnetization (CRM) with a southeasterly declination and shallow inclination. Samples farther from the fractures that are less distinctly banded or have no bands contain a weaker and less table CRM. Petrographic evidence and stable demagnetization to 600/sup 0/C indicate that the CRM resides in hematite. Samples were collected from both flanks of the Arbuckle Anticline (late Pennsylvanian folding), and a fold test demonstrates that the CRM is post-folding. The pole position for the CRM corresponds to the Early Permian (approx. 280 Ma) part of the Apparent Polar Wander Path for stable North America. These results suggest that the liesegang bands formed in the Early Permian, probably by rhythmic precipitation of hematite from fluids that moved out from the fractures. The fluids also apparently caused dedolomitization and precipitation of calcite in intercrystalline pore spaces. These fluids were probably the source of iron for the bands, although iron released from dedolimitization of ferroan dolomite may have been a local source.

• Research Organization: Univ. of Oklahoma, Norman (USA)
• OSTI ID: 6644299
• Report Number(s): CONF-8510489-
• Conference Information: Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580100 -- Geology & Hydrology-- (-1989)
580300* -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
AGE ESTIMATION
ALKALINE EARTH METAL COMPOUNDS
ANTICLINES
CALCITE
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATES
CHALCOGENIDES
DOLOMITE
FEDERAL REGION VI
GEOLOGIC AGES
GEOLOGIC FORMATIONS
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
HEMATITE
IRON COMPOUNDS
IRON ORES
IRON OXIDES
MAGNESIUM CARBONATES
MAGNESIUM COMPOUNDS
MAGNETISM
MINERALOGY
MINERALS
NORTH AMERICA
OKLAHOMA
ORDOVICIAN PERIOD
ORES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PALEOMAGNETISM
PALEOZOIC ERA
PETROGRAPHY
PRECIPITATION
SEPARATION PROCESSES
TRANSITION ELEMENT COMPOUNDS
USA