Stratigraphy to Seismic (StSTM): Integrating Biostratigraphic Interpretations with Seismic Data

Paul Watson, Caroline Reid, and Elisabeth Nairn
Fugro Robertson Ltd. (FRL), Llanrhos, Llandudno, North Wales, U.K., LL30 1SA

Biostratigraphic data are often presented in a text format with accompanying distribution charts, stratigraphic summary logs and well correlations, the quality and detail of which vary greatly. With the domination of personal computer and workstation based working practices in the oil industry, it is important that biostratigraphers provide information to the end-user in a format that is compatible with these practices ensuring that biostratigraphic interpretation, which are critical to geological understanding, are not overlooked. It is common practice within the oil industry to post important stratigraphic data at well ties on the seismic in order to constrain geophysical interpretations. This information of often only broad interpretation such as formation tops and significant age boundaries however more subtle stratigraphic details are often not easily utilised by the interpreter.

The Stratigraphy to Seismic (StSTM) technique has been developed in order to overcome this information deficit by providing stratigraphic interpretations in a digital format for integration with seismic data These interpretations are derived from a standard biostratigraphic data set and are produced as a set of curves provided in .LAS (Log ASCII [American Standard Code for Information Interchange) format which can be plotted within workstation applications. StSTM has taken the concept of providing a plot of age against depth using predominantly biostratigraphic data and developed it so that this curve gives an estimate of age at any point in the well having utilised all information available. Four other curves are also created. These are a discontinuity, a reworking, a paleobathymetry and a confidence curve. The methodology and application of these techniques are outlined below.

AAPG Search and Discovery Article #90158©2012 GCAGS and GC-SEPM 6nd Annual Convention, Austin, Texas, 21-24 October 2012