Gravity interpretation of Raguba Field, Sirte Basin, Libya

Abstract

Abstract A Bouguer anomaly map of Raguba oil field and the surrounding areas is presented and interpreted. The main features of the map are: (1) A belt of positive anomalies approaching Bouguer values of 3 mgal in the field area then increasing up to 9 mgal toward the northwest. (2) Negative Bouguer values of -20 mgal on the east and west sides and a negative value of -13 mgal on the northeast side of the field. (3) Steep anomaly gradients trending north-south on both sides of the field. To the north, the trend takes a northwest direction. (4) All these anomalies are superimposed on a regional trend of 0.16 mgal/km negative toward the south.The positive belt is interpreted as a horst structure characterized by crystalline basement at shallow depths. The negative anomalies are due to the density contrast between the sediments and the basement. Structural sections along certain profiles are presented and used for constructing gravity models calculated by computer.