Variations of the sequence stratigraphic model: Past concepts, present understandings, and future directions

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

OSTI ID:7158925

Posamentier, H W ^[1]; James, D H ^[2]

---

1. Esso Resources Canada Ltd., Calgary, Alberta (Canada)
2. Esso Exploration and Production, Leatherhead (United Kingdom)

The working hypothesis upon which the sequence concepts are based is that the relative sea level change results in changes in the capacity of a basin to accommodate sediment, which, in turn, results in a succession of sequences. The interplay between eustasy, tectonics, sediment flux, and physiography yields a predictable geologic response in carbonate, clastic, as well as mixed carbonate/clastic settings. The criteria for recognition of sequence boundaries can be varied within a given basin as well as between basins. They include but are not restricted to (1) a basinward shift of facies across a sharp bedding contact, (2) onlapping stratal geometry, and (3) truncation of strata. The key to the correct utilization of these concepts is to recognize sequence stratigraphy as an approach or a tool rather than a rigid template. Observations from the upper Albian, Cretaceous, Viking Formation of the western Canadian sedimentary basin are presented to illustrate the stratigraphic expression of clastic depositional sequences on a ramp margin. In this setting, forced regressions and lowstand shorelines commonly occur, incised valleys sometimes occur, and submarine fans rarely occur, in response to fluctuations of relative sea level. The base of the Viking Formation sometimes is characterized by relatively coarse-grained sediments sharply overlying fine-grained offshore muds and is interpreted as a third-order sequence boundary. Pebbles occasionally are observed at this contact. Subsequently, a number of higher-order sequences within the lower to middle Viking are observed and are characterized by the occurrence of forced regressions and lowstand shorelines without associated incised valleys.

• OSTI ID: 7158925
• Report Number(s): CONF-910403-; CODEN: AABUD
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 75:3; Conference: Annual meeting of the American Association of Petroleum Geologists (AAPG), Dallas, TX (United States), 7-10 Apr 1991; ISSN 0149-1423
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
ALBERTA
SEDIMENTARY BASINS
BRITISH COLUMBIA
GEOLOGIC HISTORY
GEOLOGIC MODELS
STRATIGRAPHY
CRETACEOUS PERIOD
GEOLOGIC FORMATIONS
SEA LEVEL
STRATIFICATION
VARIATIONS
CANADA
DEVELOPED COUNTRIES
GEOLOGIC AGES
GEOLOGIC STRUCTURES
GEOLOGY
LEVELS
MESOZOIC ERA
NORTH AMERICA
580000* - Geosciences