The Phenomenon Albian Cenomanian Turonian Source Rocks in the Suriname part of the Guiana Basin

Abstract

During the Equatorial Atlantic Rifting/ Drifting phase, in the northern part South America, one of the key elements was the deposition of organic carbon–rich sediments during the Mid - Late Cretaceous, which was controlled by global and local oceanographic, climatic, and tectonic elements. Now a days, this source rock is referred to as the “Canje” formation, which is the lateral equivalent of the La Luna shale in Venezuela and the Naparima Hill Formation in Trinidad. Oil from this source has been produced from the Tambaredjo, Calcutta and Tambaredjo North West oil-fields onshore Suriname and is also believed to charge the Liza discovery in the offshore area of Guyana. Numerous wells in the offshore area of Suriname have penetrated this prolific source rock. In the Ocean Drilling Program (ODP) wells, CRC-1 well, A2-1 well and NCO-1 well, high Total Organic Carbon (TOC’s) and thick Cenomanian-Turonian source rock intervals were also encountered, but they seem to be immature. The maturity of the source is believed to increase towards the NW. High quality source rock also seems to be concentrated within the Albian to the Santonian interval. Biomarkers from the onshore Oil Fields suggest that the oil that is produced, is derived from the Cenomanian – Turonian Source Rock, with other biomarkers which are believed to be derived from a more thicker source rock interval. The question to be asked is: “What is the reasoning for encountering other biomarkers in the oil from the onshore Oil Fields?” Is it age or paleo-environment related? The results presented indicate: • there might be a explanation for having different biomarkers, which also influences the distribution of this so called Canje Source Rock in the Suriname part of the Guiana Basin and responsible for the process of generation of oil in gas. • an updated maturity map for the Albian Cenomanian Turonian Source Rock, which gives a more reliable hydrocarbons potential in the “Suriname part of the Guiana Basin”.

AAPG Datapages/Search and Discovery Article #90325 © 2018 AAPG Europe Regional Conference, Global Analogues of the Atlantic Margin, Lisbon, Portugal, May 2-3, 2018