West Atlantic mesozoic carbonates: comparison of Baltimore Canyon and offshore Nova Scotian basins
Results of exploratory drilling, by Shell Offshore Inc., and its partners, of the Late Jurassic-Early Cretaceous carbonate margin of the Baltimore Canyon (BC) basin can be interpreted directly from the better understood, time-equivalent Nova Scotian (NS) basin stratigraphy. The BC paleomargin was constructed in a depositional cycle of three successive stages: Oxfordian-early Kimmeridgian progradation, Kimmeridgian-Berriasian aggradation, Berriasian-Valanginian drowning. The upper two stages in NS are the Baccaro and Artimon members of the Abenaki formation. The progradation of the lower sequence in BC results from high clastic input and has a parallel (not age equivalent) in NS only in proximity to the Sable Island paleodelta. Both basins have similar, complementary, shelf-edge environments that form a single water-depth-controlled biotic zonation. This zonation is: shallow-water stromatoporoid-hexacoral biostromes and reefs; deeper water stromatactis and thrombolitic mud mounds; and deep-water lithistid sponge reefs. Associated environments are oncolitic reef flats, reef-apron skeletal sands, slope reef debris from sponge and coral reefs, and back-reef mollusk-rich skeletal and skeletal-oolitic sands. Major differences between the basins are the pinnacle reefs of BC and the contrast between the mud-rich skeletal and nonskeletal megafacies of NS versus the dominantly skeletal sand-rich BC sediments. The higher subsidence rates of BC may explain both differences.
- Research Organization:
- Shell Canada Resources, Calgary, Alberta
- OSTI ID:
- 5376744
- Report Number(s):
- CONF-860624-
- Journal Information:
- Am. Assoc. Pet. Geol., Bull.; (United States), Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Vol. 70:5; ISSN AAPGB
- Country of Publication:
- United States
- Language:
- English
Similar Records
Results of exploration in Mesozoic shelf-edge carbonates, Baltimore Canyon basin
Origin of Silurian reefs in the Alexander Terrane of southeastern Alaska
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
ATLANTIC OCEAN
BALTIMORE CANYON
CANADA
CARBONATE ROCKS
CRETACEOUS PERIOD
EXPLORATION
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC HISTORY
GEOLOGY
JURASSIC PERIOD
MESOZOIC ERA
MINERAL RESOURCES
NORTH AMERICA
NOVA SCOTIA
PETROLEUM DEPOSITS
RESOURCES
ROCKS
SEAS
SEDIMENTARY ROCKS
STRATIGRAPHY
SURFACE WATERS