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Pros and Cons of 2D Crooked Seismic Profiles for Deep Mineral Exploration - A Comparison with 3D Surveys in Geologically Complex Mining Environment
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, EAGE/DGG Workshop on Deep Mineral Exploration, Mar 2016, Volume 2016, p.1 - 5
Abstract
Despite being applied for nearly three decades now, the seismic methods for deep mineral exploration are routinely carried out using 2D profiles along existing roads requiring crooked-line methods. While the assumption of a 2D geology is rarely valid in most mining environments, no follow up or very little 3D surveys are attempted. Using synthetic seismic data and case studies, we illustrate that 3D seismic surveys should ultimately be carried out for detailed interpretations and for direct targeting of mineralization. We show for example that a bright-spot seismic anomaly observed on a 2D seismic profile was associated with an approximately 6 Mt of massive sulphide mineralization that was targeted, after being delineated on 3D seismic volume, about 500–700 m off the 2D profile at about 1.2 km depth but shallower than that observed in the 2D profile. The mineralization produced a noticeable diffraction signal in the 3D unmigrated volume with certain characteristics providing information about the geometry and possibly the mineralization content. Using another case study we show how sometimes 2D crooked-line data can provide information about accurate delineation of small objects in 3D. Nevertheless we argue that nothing would replace a proper 3D seismic survey and encourage this to be done if exploration to be successful.