Uncovering the hidden secrets of one of the world’s largest shale plays
A supermajor wanted to sequence a drilling program designed to test the potential of unconventional shale development in Argentina’s Neuquén Basin. The size of the area, volcanic intrusions, time pressures, and topography all challenged new seismic acquisition. An integrated interpretation of airborne geophysical datasets helped to illuminate key regional geologic features, including basement topography, localized faulting and intrusions, and reservoir thickness and burial depth. Other project work streams identified total organic carbon (TOC) variations and oil seep locations to highlight high-BTU portions of the play, while a multi-variate geostatistical technique helped to map estimated gas-in-place across thousands of square kilometers and to sequence new appraisal wells.
Argentina’s Neuquén Basin is one of the world’s most dynamic and underexplored hydrocarbon systems. Its two principal shale targets – Los Molles and Vaca Muerta – have been rich source rocks for the conventional reservoirs that have been produced in the basin for more than 50 years. With new technologies available for unconventional asset exploration and development, producers are taking a second look at these extremely thick oil- and gas-charged shales. While several seismic and non-seismic datasets have been acquired the coverage lacks uniformity, and no one has been able to integrate the data into a single, actionable interpretation — until now.
We have acquired high-resolution, airborne geophysical data over 30,000 square kilometers of the Neuquén Basin. Using innovative, multi-measurement methodology, we have integrated these new measurements with existing well, geological, geochemical, and seismic data available in the public domain, from third parties, and from the project’s underwriters. We designed the Neuquén study to provide the project’s underwriters with an enhanced basement-to-surface understanding of the basin and its potential.
Initially, high-resolution hyperspectral imaging was acquired to map the regional lithology, the total organic carbon (TOC) of the target shales, and oil seeps and indirect hydrocarbon indicators on the surface. A second work stream generated 3-D models constrained by the structural aspects of existing seismic lines, available well data, and newly acquired gravity and magnetic measurements. These models provided useful exploration insights by depicting isopachs, burial depth, depth-to-basement, and proximity-to-intrusives for all target shale horizons.
The team also developed a new hydrocarbon maturation model by combining the 3-D model, existing basin TOC models, and surface samples. This analysis identified new areas of opportunity previously considered to be overmature. By interpreting the locations of volcanoes and intrusions from airborne magnetic data, a new thermal regime was evaluated, providing evidence of and refuting the misconception that intrusions had terminally degraded regional opportunities.
Finally, we combined all datasets using a geostatistical data mining technique called predictive analytics. By analyzing key attributes – including shale thickness, the potential for generated and retained liquid hydrocarbons, and a relatively flat topographic area for drilling – we and client geoscientists high-graded acreage to identify optimal drilling locations and reveal the lucrative secrets of the Neuquén.
Neuquén Basin, Argentina
FOCUS Regional Mapping
KEY INTERPRETIVE PRODUCTS
- Regional 3-D subsurface models
- Horizon-specific isopach maps
- Estimates of gas-in-place on an areal basis, developed using a multi-variate geostatistical analysis
Reveals new prospectivity in the frontier portion of an established basin by integrating new airborne geophysical measurements with existing seismic, well, and geological and geophysical (G&G) data.