Two-dimensional synthetic seismic and log cross sections from stratigraphic forward models

Journal Article · Tue Mar 01 00:00:00 EST 1994 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:6833439

Shuster, M W ^[1]; Aigner, T ^[2]

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1. KSEPL (Shell Research), Rijswijk (Netherlands) Shell Development Company, Houston, TX (United States)
2. Universitaet Tuebingen, Tuebingen (Germany)

In an effort to fully use deterministic stratigraphic forward-modeling techniques in subsurface stratigraphic analysis, we developed a computer interface to routinely create synthetic logs and one-dimensional and two-dimensional (2-D) seismic responses from 2-D stratigraphic simulations. Each 2-D stratigraphic model can contain up to 200 timelines defining age-equivalent stratigraphic layers with laterally variable lithofacies and depths. Synthetic gamma ray, density and velocity responses are calculated for the simulated lithofacies using user-specified rock and fluid properties. Vertically incident synthetic seismograms are created using calculated reflection coefficients and user-defined input wavelets. The power of this technique as an aid in sequence stratigraphic interpretations is shown from three examples: (1) a simulation of an idealized clastic system assuming constant clastic input and sinusoidal fourth-order and third-order sea level variations, (2) a detailed simulation of one third-order carbonate depositional sequence (lower-middle San Andres Formation) from the Northwest shelf, Permian basin, and (3) simulations of the Permian mixed clastic-carbonate infill of the Midland basin. Some general conclusions from these examples include the following: (1) seismic and well log-defined topsets, foresets, bottomsets, and related event terminations can be directly related to relative sea level fluctuations, (2) Exxon-type sequence boundaries (i.e., unconformities) are not necessarily seismically imageable, and their identification on well logs is not straight-forward, and (3) lateral variations in amplitude related to lithofacies variations can be modeled. Synthetic logs and seismic sections from stratigraphic forward models such as these may be useful in constraining interpretations of subsurface data and thus aiding the prediction of reservoir and seal distribution. 19 refs., 13 figs., 2 tabs.

• OSTI ID: 6833439
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 78:3; ISSN 0149-1423
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
GEOLOGIC STRATA
GEOLOGIC MODELS
TWO-DIMENSIONAL CALCULATIONS
RESERVOIR ROCK
DISTRIBUTION
SEISMIC SURVEYS
COMPUTERIZED SIMULATION
WELL LOGGING
COMPUTER CODES
CROSS SECTIONS
SEA LEVEL
STRATIGRAPHY
GEOLOGIC STRUCTURES
GEOLOGY
GEOPHYSICAL SURVEYS
LEVELS
SIMULATION
SURVEYS
020200* - Petroleum- Reserves
Geology
& Exploration