Allostratigraphy of stacked prograding coastal sediments in the Lea Park-Belly River transition (Campanian) of Central Alberta

Conference · Fri Mar 01 04:00:00 EST 1991 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:7158917

Power, B A; Walker, R G ^[1]

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1. McMaster Univ., Hamilton, Ontario (Canada)

The Lea Park-Belly River transition in central Alberta comprises a downlapping wedge of coastal sediments. The transition is characterized by numerous stacked shoreface successions that young in an eastward direction. They are very sharply based such that the transition between the mid/lower shoreface and the shelf sediments is either absent or very thin. The shoreface successions are laterally equivalent to incised fluvio-deltaic sediments and are interpreted to indicate forced regressions, where a relative drop in sea level causes the shoreline to move rapidly basinward. The most likely cause of these regressions is a change of subsidence rate due to active loading in the Cordillera acting in concert with a third-order relative drop in sea level. Subsidence due to tectonic loading would allow for the aggradation of coastal sediments. During periods of lesser subsidence or greater sea level drop, distributions would incise and the position of the shoreline would move rapidly basinward, resulting in the subsequent sharp-based shoreface succession. This may indicate that in foreland basins, where subsidence acts to cancel relative drops in sea level, sequence boundaries due to third-order drops in sea level may be replaced by a stacked wedge of sharply based coastal successions.

• OSTI ID: 7158917
• Report Number(s): CONF-910403--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (United States) Journal Volume: 75:3
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ALBERTA
CANADA
DEVELOPED COUNTRIES
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
GEOLOGY
LEVELS
NORTH AMERICA
SEA LEVEL
SEDIMENTARY BASINS
SEDIMENTATION
STRATIGRAPHY
VARIATIONS