DYNAMIC STRATIGRAPHY WORKGROUP

Environments in Early to Mid Eocene Tyee Basin, Oregon

 

People:

Manasij Santra, Ron Steel, Mike Sweet

 

Research question(s):

The major questions that are expected to be addressed include the following:

1)      Evaluation of the stratigraphic configuration of Tyee Formation and establishing a stratigraphic framework, consistent with a series of prograding shelf-slope-basinfloor       clinoforms

2) Understanding the mechanism of significant sand supply to deepwater basin floor areas during a greenhouse time period (latest early Eocene) with relatively low magnitude and frequency of eustatic sea level variation.

3) Characterization of the deltaic deposits on the Tyee shelf, and their role as greenhouse feeders to the deep water (slope to basin floor) depositional regime.

4) Characterization of the deep water channel deposits associated with slope deposits and fan complexes within Tyee Formation.

 

 

Publications and presentations:

 

Publications:

 

Conference Presentations:

 

Slope-channels and fan-channels from Early to Mid Eocene strata of Coast Range, Oregon

M. Santra, R. J. Steel, M. Sweet (AAPG Meeting, San Antonio, 2008)

 

Summary of work:

Tyee Basin in Coast range of Oregon is a forearc basin that developed in Early Eocene as a response to subduction of Farallon Plate under North American Plate.  Tyee Basin       succession includes very thick highly sand-rich deepwater turbidites, fine-grained slope deposits and predominantly sandy fluvial to shelf-deltaic deposits.

The above problems will be addressed through combining a number of detailed measured sections and well-log correlations in the Tyee basin.

Thick deep-water sandstones from Tyee Formation, Oregon