Dr. Posamentier will give a public lecture on Thursday, February 28 in BSB D109 from 7-8pm. The public lecture is titled Remote Sensing of the Earth - Imaging Deeply Buried Depositional Features Using 3D Seismic Data and will focus on modern 3D seismic data has revolutionized the way we explore for oil and gas. These data allow for the direct imaging of depositional elements such as channels and reefs buried deep below the earth's surface. Once such depositional elements are recognized earth scientists can then infer the distribution of sand and shale and predict the presence or absence of reservoir rocks prior to drilling. This approach has significantly reduced uncertainties associated with lithology prediction. Through the use of high-powered workstations, earth scientists integrate interpretation of images in cross section with images in map view. In effect, this involves the joining of two disciplines: stratigraphy - the study of the architecture of geologic layers (i.e., strata) - and geomorphology - the study of landforms. Analysis of 3D seismic volumes involves workflows similar to those employed in the analysis of CAT scans and ultrasound imaging. Seismic volumes are "sliced and diced" in creative ways to bring out images of paleo-landscapes and seascapes. Numerous examples from a variety of depositional settings ranging from tropical marine reefs to continental rivers to deep-water channels will be shown.
There will also be a technical lecture given on Friday, March 1 from 3-4pm in BSB E231. The public lecture is titled Integration of Seismic Stratigraphy and Seismic Geomorphology for Prediction of Lithology; Applications and Workflows.As high-quality 3D seismic data has become widely available, stratigraphic interpretation has significantly improved our ability to predict the subsurface distribution of lithologies. Stratigraphic interpretation of seismic data involves the integration of stratigraphy and geomorphology, with integrated section and plan view images yielding robust interpretations of stratigraphic architecture and associated lithology. With the investment of billions of dollars in acquisition and processing of seismic data, maximizing the value of that investment by extracting as much information from these data is business critical.
Seismically-derived geologic interpretations can have significant impact on exploration and production in the following ways:
Geology: 1) prediction of lithology, 2) prediction of compartmentalization , 3) development of depositional analogs, 4) Enhanced understanding of geologic processes. Through a variety of techniques, it is possible, in many instances, to image significant parts of depositional systems. Components of depositional systems, i.e., depositional elements such as channels, patch reefs, etc., are then identified and yield insights as to the lithology of these deposits. Subsequently, further analysis can provide insights as to stratigraphic compartmentalization.
Geophysics: 1) provides depositional context for geophysical analyses (e.g., DHI analysis, reservoir properties from seismic), and 2) quality control for geophysical processing. Understanding geologic context can provide a "reality check" when evaluating geophysical data for rock and fluid properties. In addition, iteratively evaluating the effects of geophysical reprocessing on geologic (i.e., stratigraphic and geomorphologic) features so that such features are not processed out of the data, is critical to maximizing the value of seismic data.
Key aspects of successful application of seismic stratigraphic analysis are: 1) integrating section and plan views in an iterative workflow, 2) understanding and recognizing geologically-meaningful patterns both in section and plan view, and 3) having efficient and creative workflows to quickly analyze geophysical data.