Hydrocarbon seepages occurrences are well known all over the world and historical references to hydrocarbon seepages date back to the earliest records. Historically, natural hydrocarbon seeps have provided a useful tool for petroleum exploration. Hydrocarbon seepages occurrence provides surface or sub-surface expressions that make it possible to be detected using different direct or indirect exploration methods. The surface expressions can take many forms, including simple ponds, oil stained rocks, microbiological anomalies and the formation of paraffin dirt, mineralogical changes such as formation of calcite, pyrite, uranium, elemental sulfur, and certain magnetic iron oxides and sulfides; bleaching of red beds, clay mineral alteration, electrochemical changes, radiation anomalies, and biogeo-chemical and geobotanical anomalies.
Satellite-based remote sensing of hydrocarbon-induced alterations is one of the exploration methods being used to map areas of hydrocarbon seepage occurrences all over the world. The method provides a synoptic view needed to study the spatial variability that occurs in areas of seepage occurrences and holds great promise as a rapid, cost-effective means of remote detection of anomalous diagenesis in surface soils and rocks.
IPEX has tested the method over the Amazon and Congo forests with considerable success.