Modeling Sedimentary Deposits on the Continental Margin
Abstract
LONG TERM GOAL. The long-term goal of my research group is to construct mathematical descriptions of the processes that form sedimentary deposits at all spatial scales on continental margins, from storm beds to the deposits of 100,000 yr sea level cycles; and to conduct numerical experiments leading to the prediction of the sedimentary fabric (structure, stratification pattern) of the resulting deposits. OBJECTIVES. A first objective is to investigate the fabric (pattern) of seabed stratification on continental margins at small time and space scales (1 cm-50 cm depth into the seabed; 1 hr-3 yrs sedimentary record). To this end, we are testing the hypothesis that on muddy shelves such as the northern California shelf, Holocene event stratigraphy consists of the deposits of high-concentration storm regimes associated with river floods, alternating with deposits of low-concentration storm regimes. In order to conduct the test, we have developed several deterministic algorithms, in collaboration with our subcontractors, Alan Niedoroda and Chris Reed, at URL Greiner Woodward Clyde, Tallahassee. These algorithms, (EVENT, RESUSPEND, and TRANSPORT), that are driven directly by STRATAFORM and NOAA current meter records. At intermediate spatial scales (1 -20 m depth into the seabed; 1-1,000 yrs), we are testing a second hypothesis. The hypothesis states that facies assemblages are stacked on, or are capped by, erosional bounding surfaces (source diastems,) in patterns reflecting fluid power gradients in the parent dispersal system; and that these patterns are responses to progressive sorting and stratal condensation mechanisms. At these intermediate time and space scales, flood and storm current records are not available. In order to conduct the test, we have embedded EVENT in an algorithm (FACIES) that is driven by probability density functions describing flood and storm current frequencies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1999
- Accession Number
- ADA629727
Entities
People
- Donald J. Swift
Organizations
- Old Dominion University