The validity of the magnetic method in discriminating Jurassic Volcanics from hydrocarbon traps : a case study in offshore Malta

Abstract

The capability to discriminate between Jurassic volcanic mounds and hydrocarbon traps can determine to a large extent the success of exploration for petroleum in the Ragusa Basin north of Mallet. The suitability of the magnetic method as a discriminating tool over Area 3 north of Malta is investigated through the application of an inverse modelling algorithm to an area adjacent to the Valletta 1 well. Although the results of the inverse process are indicative of magnetic bodies at Jurassic depths, the anomalous field generated by the calculated bodies deviates from the actual field. An application of a forward process to generate the anomaly due to a model based on a structure defined by Amoco and incorporating depth and susceptibility data as measured from the Valletta 1 well is also included. The generated anomaly is not visible on the field data.