In this First Break article from March 2025, experts Pedro V. Zalan (ZAG Consulting), Milos Cvetkovic, Henri Houllevigue, Kyle Reuber and Andrew Hartwig (TGS) present a new, distinctive prospect in the southern Santos Basin, constituted a possible Albian atoll developed upon exhumed mantle.
Introduction
The Santos Basin in southern Brazil became famous for the fabulous reserves of oil and gas in the Aptian microbialite reservoirs of the so-called ‘Pre-Salt Play’. Super-giant fields such as Tupi and Búzios, and giant fields such as Sapinhoá and Mero, among others, produce close to 2 million boepd. These fields and numbers blur the modest existence of different, but still effectively producing, oil and gas fields in the so-called ‘Post-Salt Plays’. Numerous turbidite-hosted and carbonate-hosted oil and gas fields are also noteworthy in terms of reserves and production. The objective of this work is to present one quite unusual prospect in the Post-Salt Play.
Figure 1 - Location of Ametista Block on the map of the crustal provinces of the Santos and Campos Basins (modified from Zalan, 2024). Notice its special location upon the V-shaped tip of exhumed mantle. Albian string of pearls refers to several producing Albian age carbonate-hosted oil and gas fields.
The Ametista Block in southern Santos Basin is one of a kind; half of its area is inside the Pre-Salt Polygon, regulated by Production Sharing directives, and the other half is situated outside the polygon, regulated by Concession regime (Figure 1). Until recently, all the interpretation and basin evolution assessment have been done on gravity and magnetics data, aided by 2D seismic data, some of it acquired and processed 10-15 years ago.
Read the full article here.