Abstract:
The Potiguar Sedimentary Basin stands out as one of the most significant in Brazil within the exploratory oil and gas landscape. Located on the Brazilian Equatorial Margin, its exploration began in the 20th century. With technological advancements and results obtained from studies conducted in related basins along the African coast, new investigations have been proposed, particularly focusing on offshore areas that still require more detailed research.
Thus, this study aims to investigate the evolutionary processes of the Potiguar Basin through the application of geophysical methods, including magnetometric and geothermal analyses. A set of 382 direct geothermal data was utilized in this study, and the crustal heat distribution within the basin indicates three (3) major positive anomalies in the emerged portion of the Potiguar Basin. Two of these anomalies are located in the S-SE portion of the basin with an average geothermal gradient of 52° C/km, while the third anomalous region is situated to the NW with a gradient around 45°C/km. The heat flow observed in these same regions exceeds 120mW/m² in the S-SE portion, whereas in the NW region, it is 100mW/m². The magnetometric information reveals a structural context of the basin with a predominant NE-SW direction of its magnetic lineaments, which corroborates with the directions of the structural framework mapped in the basin.
At the end of this research, significant geothermal anomalies were identified, especially associated with the Carnabaús and Seridó domains, where sedimentary content is shallow compared to the depocenter of the basin. These anomalies, located in fault regions, are influenced by both morphostructural aspects and volcanic activity that has occurred in the area. Additionally, geothermal modeling and spectral analysis of aeromagnetometric data showed agreement, highlighting a shallower Curie isotherm with depths between 8 and 11 km, which supports the thermal anomalies identified in the basin.
