Limitations of the technology

RSDD-H surveys are not a panacea for petroleum exploration but they offer a valuable additional tool in any explorer's campaign to build a prospect inventory and to reduce exploration risk.

The main issues impacting the quality and effectiveness of an RSDD-H survey relate to a) the volume and quality of suitable satellite imagery in any particular survey area and b) the specific nature of a survey area's landscape.

Several parts of the world are difficult survey terrains on one or both of these accounts. Areas of protracted cloud cover have small volumes of suitable images to work with. This is mitigated by the size of the excellent Landsat MSS archive that spans some twenty years of data acquisition form 1972 through 1992. Usually, there will be a few sets of workable images in this collection even for particularly difficult areas.

Careful examination of any landscape invariably shows heterogeneities. Sometimes these are minor, sometime they are major. Sometimes they are natural, sometimes they are man-made or "technogenous". Some of these particular heterogeneities can mask the primary hydrocarbon-induced RSDD-H response or create quite clear "false anomalies". Fortunately, Scotforth has developed a strong awareness of these masking and false anomaly creating conditions and can often mitigate them with detailed local processing efforts. However, the PI of such terrains will still be risked higher than that of more favourable terrains.

The exploration risk model applied by Scotforth to the PIs of its surveys brings transparency and objectivity into the inherent uncertainties of survey results. This approach, together with the discussion of survey quality issues in the text of survey reports offers survey users maximum awareness of the perceived quality and effectiveness of RSDD-H results in any given survey.