11 December, 2013

Eagle Ford Shale Prospecting with 3D Seismic Data within a Tectonic and Depositional System Framework


The Eagle Ford Shale in South Texas is one of the more exciting shale plays in the United States at the current time.

The Eagle Ford Shale in South Texas is one of the more exciting shale plays in the United States at the current time. Recently published reports of well tests describe gas well rates exceeding 17 mmcf/d and oil well rates in excess of 1500 bopd and unconfirmed rates of 2000 bopd. Acreage lease rates continue to climb as more positive results come from drilling within the trend. A key issue for the exploration companies is finding where to focus acreage acquisition and optimize drilling plans for optimal gas and oil recovery. Our paper will first consider the geologic context of the Eagle Ford and then look at geophysical techniques, in particular, comparing and contrasting the value of 3D Processing seismic attributes in building a successful exploration plan.

Conventional subsurface data, such as wireline logs, cores and cuttings, are limited in availability to many companies currently exploring the play. Interpretation of these data is often ambiguous at best. As a result, thorough understanding of the regional aspects of the play remains elusive to many companies. It is our belief that modern seismic data and interpretation techniques can add significantly to the database and greatly enhance regional understanding of the play for many companies. Newly acquired 3D datasets provide a continuous characterization of the subsurface, which highlights drilling hazards (faults), and also offers the potential for identifying better reservoir quality intervals (higher TOC shale sections with greater porosity and fractures). Extracting rock properties from the seismic should be the goal of any processing and interpretation effort. Linking the results of well tests to the attributes derived from the seismic will provide operators with a far more reliable predictive capability in any shale play.

Ultimately, the pursuit of Eagle Ford acreage and the designing of an Eagle Ford drilling campaign is best accomplished through a comprehensive understanding of the geologic framework coupled with a focused interpretation of the seismic. This shale is one of the more exciting domestic shale plays, and presents ample opportunities to make and lose money. The smart operator will utilize all the tools available to study the target section while recognizing the limitations of the technology.

Key Topics will include:

  • Seismic data
  • Heterogeneities in the Eagle Ford
  • Isochron and Isopach maps
  • Coherence and curvature attributes
  • Lineaments associated with small-throw faults and possible fracture trends
  • Seismic data offer a number of opportunities to understand potential heterogeneities in the Eagle Ford
  • Amplitude variation implications
  • Full azimuth data
  • Long offsets
  • High frequency / High fold data

Structure of the E-Symposium

Each e-symposium consists of one-hour live e-symposium, along with material for one full day of independent study. The live portion will be followed by a full day of independent study (not a live event). The one-hour live e-symposium can be accessed from any computer anywhere in the world using a high-speed internet connection. After the event is over, you will receive via email information about accessing the asynchronous segment (not live) which consists of your independent study materials, to be accessed and studied at any time. You will be able to email responses to the readings, along with your study question answers for CEU credit (if you sign up for the extended package).