Efficiency of Remote Sensing for the Environmental Management of Seismic Surveys in Desert Exploration Areas

Abstract

Onshore seismic surveys may have visible impacts on the environment, especially in desert regions. In these areas, existing maps are often out-of-date, unavailable or inappropriate. The performance of remote sensing and Geographic Information Systems (GIS) is such that these tools are increasingly useful in the planning of environmental baseline surveys, reporting of environmental data and monitoring of environmental impacts. TOTAL has developed and tested state-of-the-art remote sensing and GIS technologies through the performance of several environmental baseline surveys for projects in North Africa. Very high resolution satellite data with a ground resolution of up to sixty centimeters was used. The trials indicate that the use of remote sensing and GIS is an efficient way to characterize environmental baseline conditions in remote areas when a limited timeframe is available.. Geospatial imagery is a cost-effective way to produce detailed baseline maps of sensitive areas highlighting wadis, cliffs, agriculture, foggaras, wetlands, tracks, towns and socio-economic activities. Accurate geospatial information helps to reduce costs by optimizing the time spent in the field and enhances the efficiency and quality of environmental studies. In addition, field photographs, observations, investigations and measurements can be directly integrated into GIS geodatabases. State-of-the-art methodologies and solutions for multi-date analysis enabling any change in the environment to be detected have been developed and tested; and now routine advanced remote sensing can accurately characterize the impacts of seismic surveys in arid and semi-arid environments. Objectives Geospatial imagery and Geographic Information Systems (GIS) has many applications in the petroleum industry. The technologies for the observation of the earth from space and for digital mapping have evolved very quickly and new solutions that were previously expensive and complex to use are now used in a routine manner. The usefulness of geospatial imagery and GIS in the performance of environmental impact assessments in different environments and for all phases of exploration and production is already recognized. This paper presents how the use of satellite images can improve the efficiency of the performance of environmental impact assessments in desert regions, in particular in a context of seismic surveys. The example project presented in this paper is the post-seismic survey environmental impact audit carried out over 900 km2 of desert near the city of Timimoun. The audit was performed by a multidisciplinary team comprising experts from TOTAL, TTI Production and Sogreah Magelis. Work Area TOTAL has performed a number of seismic surveys in North Africa over the last few years. The satellite imagery acquired as part of these previous surveys provided important information which was used to plan the post-seismic survey environmental impact assessment and to identify possible environmental constraints to be considered in the planning of the field work.