Abstract
The stratal architecture of deep-water minibasins is dominantly controlled by the interplay of two factors, structure growth and sediment supply. In this paper we explore the utility of a reduced-complexity, fast computational method (Onlapse-2D) to simulate stratal geometry, using a process of iteration to match the model output to available subsurface control (well logs and 3D seismic data). This approach was used to model the Miocene sediments in two intersecting lines of section in a complex mini-basin in the deep-water Campeche Basin, offshore Mexico. A good first-pass match between model output and geological observations was obtained, allowing us to identify and separate the effects of two distinct phases of compressional folding and a longer-lasting episode of salt withdrawal/diapirism, and to determine the timing of these events. This modelling provides an indication of the relative contribution of background sedimentation (pelagic and hemipelagic) vs. sediment-gravity-flow deposition (e.g. turbidites) within each layer of the model. The inferred timing of the compressional events derived from the model is consistent with other geological observations within the basin. The process of iteration towards a best-fit model leaves significant but local residual mismatches at several levels in the stratigraphy; these correspond to surfaces with anomalous negative (erosional) or positive (constructive depositional) palaeotopography. We label these mismatch surfaces “informative discrepancies” because the magnitude of the mismatch allows us to estimate the geometry and magnitude of the local seafloor topography. Reduced-complexity simulation is shown to be a useful and effective approach, which, when combined with an existing seismic interpretation, provides insight into the geometry and timing of controlling processes, indicates the nature of the sediments (background vs. sediment-gravity-flow) and aids in the identification of key erosional or constructional surfaces within the stratigraphy.
Highlights
The Sureste Basin, located in southern Mexico is a world class basin for hydrocarbon exploration and production with proven reserves of more than 50 Billion bbl of oil
The overall aim of this study was to utilize a forward stratigraphic modelling software, Onlapse-2D to better understand the tectonostratigraphic evolution of the Late Miocene section in three adjacent minibasins in a geologically complex area located in the offshore Sureste Basin
A single, simple Structural Growth Profile that grew at a constant rate at each Time-Step was used
Summary
The Sureste Basin, located in southern Mexico is a world class basin for hydrocarbon exploration and production with proven reserves of more than 50 Billion bbl of oil. A complex geological history and the fact that exploration has only recently begun to focus on deep-water makes the Sureste Basin an ideal area to test the stratigraphic forward modelling program Onlapse-2D. Sedimentation Rate This is the amount of sediment deposited uniformly along the cross section through pelagic and hemipelagic settling (Figure 3D). While it is spatially constant at any one time, the rate of Background Sedimentation can change through time. We calculated this from two interpreted condensed sections within the interval of study in Well-A that had good biostratigraphic age constraint. Onlapse-2D inherits all the assumptions that are made when matching to subsurface data such as reflection seismic or well logs
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
