Petroleum System Of The Barinas Basin: A 2D/3D Basin Modeling Approach Rojas Iliana (PDVSA-INTEVEP) Copyright 2012, ALAGO. This paper was selected for presentation by an ALAGO Technical Committee following review of information contained in an abstract submitted by the author(s). Abstract Caribbean Deformation Front to the North and Arco de The study area is located towards the North of the Caribbean Merida to the South (Figure 1). Deformation Front; specifically where the structures of Sipororo, La Yuca and Barrancas oils fields are located, near the Barinas Traditional oil Fields. From a structural point of view, the area of interest is bounded by the following structural features: Bocono Fault Northward, Arco de El Baul East, Caribbean Deformation Front to the North and Arco de Merida to the South and have been studied with the aim build 3D/2D basin model using 3D Temis and some 2D lines (2D Venezuela Temis), with the purpose of determining the different elements (crude oils /source rock, reservoirs, seals and traps) and processes (maturity, migration, transformation ratio, generated and expelled hydrocarbon volume) by the source rocks and South America their contribution with charge of the proposed exploration opportunities in the area, in order to integrate and update previous studies in the Barinas Basin. The methodology developed was first to evaluate the Barinas Basin geochemical characteristics of the crude oils and rocks. Then, Figure 1. Location map of the studied area showing the main from geological-structural model proposed in the area, was structural elements. built a geochemical modeling 2D and 3D as a result of the interpretation performed on 2D (15.520 km) and 3D (1.350 The sedimentary column covers ages from km2) surveys. The results model 2D/3D suggest two possible Cretaceous to Recent age. It includes mainly: Basamento, intervals for generation and expelling potential hydrocarbons Aguardiente, Escandalosa (reservoir), Navay (source rock), of Cretaceous age: the Quevedo and La Morita Members of Burguita, Gobernador (reservoir), Masparrito, Paguey (seal), Navay Formation were identified in the Northwest of the study Parangula and Rio Yuca formations. Four major tectonic area, which were active in the Miocene and currently at levels events led to the current basin: Pre-rift during Paleozoic, rift equivalent to maturity phase of maximum generation of liquid and drifting during Jurassic and early Cretaceous, Passive hydrocarbons (1.3% Ro).These hydrocarbons have migrated margin during the Cretaceous and active margin from vectors a Northwest-Southeast direction, towards the Barinas Cenozoic to the recent with the development of a flexural Basin. Thus, according to the result of this model and Mass Basin and the foreland basin (Figura 2). AGE PETROLEUM OPER PALEOENVIRONMENTS FORMATION / MERBER SYSTEM GEODYNAMIC Balance the opportunities displayed on the study area, have PERIOD/EPOC NAME C T NI NM NE BS ELEMENTS QUATERNARYCUATERNARIO ALUVIONES n n t t a a f PLIOCENE f i received enough volume of oil from these Cretaceous source PLIOCENO RIO YUCA YUCA i l l e . e p p d MIOCENO d n MIOCENO PARANGULA n U MIOCENE PARANGULA U Basin Foreland A rocks (Miocene generation) (5035.31 MMBLS) and its lateral A OLIGOCENEOLIGOCENO O O TARDIO S I I LATE equivalent La Luna Formation (generation in the Eocene), PAGUEY Flexural Basin, R R A A Foreland type I I A O O C C N MASPARRITO N E E MEDIO R directly or through remigration oil that was accumulated in the R C C E E MIDDLE O O Active margin (Cenozoic to TERTIARY EOCENE B T E R C I A R I R O I A TI R C E O R I R C A ETI EEOCENO EEOCENO GOBERNADOR R Barinas fields. Molecular parameters have allowed C the recent) TEMPRANOEARLY Caribbean, Napas de Lara, corroborating the crude oils Northem Barinas and traditional PALEOGENEPALEOCENO Merida Arc MAASTRICHTIANMAASTRICHTIENSE BURGUITA D Barinas areas have mainly marine origin with some Beginning of the Uplift E contribution of terrestrial organic matter and different levels of F CAMPANIENSE G H LOWERTEMPRANO QUEVEDO I maturity and biodegradation. CAMPANIAN A J Passive Margin TO K (During the CONIACIANCONIACIENSECONIACIENSE NAVAY L SR M Cretaceous) Keywords: oil, generation, expulsion, migration, entrapment, O E C CONIACIENSE CONIACIANA Á Á CONIACIENSETURON.TARDIO CRETACEOUS geochemical, structural. T TO UPPERA LA MORITA N E TURONIANTURON.TARDIO R C O Deepeding of the passive MIDDLETURON. TURONIAN MEDIO P TO LOWERA ESCANDALOSA R margin during Introduction CENOM.TEMPRANOCENOM.TEMPRANO R CENOMANIAN S ofseparation of South LOWER CENOM.TEMPRANO and North America CENOMANIANA TO T The study area, is located towards the North of the Caribbean AGUARDIENTE UPPERALBIENSE ALBIAN TARDIO Deformation Front; specifically where the structures of ALBIENSEALBIENSE TEMP.TEMP. LOWERA ALBIAN Post “Rift” (Early NEOCOMIENSE Sipororo, La Yuca and Barrancas oils fields are located, near Cretaceous) PRE-CRETACEOUSPRE-CRETACEO BASAMENT BASAMENTO = Erosi “Rift” (During Jurassic) the Barinas Traditional oil Fields. The UTM area coordinates Erosion T= Transitional NM= Medium Neritic BS= Batial C= Continental NI= Neritic Internal NE= External Neritic boundaries are: Xmax = 410000, Xmin = 335,000, Ymin = Modified from: Meza M. (2000) 910,000 and Ymax = 990,000. From a structural point of view, Figure 2. Stratigraphic column type of the Barinas sub-basin the area of interest is bounded by the following structural and the main elements of the petroleum system (Reproduced features: Bocono Fault Northward, Arco de El Baul East, and modified from Lisbeth Meza, 1995). 2 ROJAS ILIANA The development of the model presented was in this Results and Discussion paper done mainly from the 2D/3D seismic data (seismic The results were divided in two ways: The Petroleum System transects and map in depth), key wells available and the Elements and the Petroleum System Processes. interpreted stratigraphic framework interpreted from this data. Key tops formations were identified, as well as eroded Petroleum System Elements thicknesses, formation ages, lithology of each interpreted Crude Oils / Source Rock sequence and geochemical parameters of the source rock such: The crude oils Northem Barinas and traditional Barinas areas total organic richness, effective thickness and type of kerogen. have mainly marine origin (carbonate and/ or shale) with some contribution of terrestrial organic matter and different levels of Objective maturity to increase from Southwest to Northeast in the study Building a 3D/2D basin model using 3D Temis and some 2D area. The biodegradation can be interpreted in different levels, lines (2D Temis), with the purpose of determining maturity, ranging from high in the seeps studied, to moderate and low, migration, transformation ratio, generated and expelled in some cases as presented of the Barinas fields (figure 5). hydrocarbon volume by the source rocks and their H contribution with charge of the proposed exploration opportunities in the area, in order to integrate and update O previous studies in the Barinas Basin. D K AA A M B 3 T AB Methodology AC F The methodology developed was first to evaluate the geochemical characteristics of the crude oils and rocks. Then, Z Y from geological-structural model proposed in the area, was built a geochemical modeling 2D and 3D as a result of the 2 interpretation performed on 2D (15,520 km) and 3D (1,350 km2) surveys (figure 3,4). 1 1.- Evaluation of the geochemical Figure 5. General Characteristics of the crude oils and seep characteristics of crude oils and rocks oils of Barinas area: the origin, maturity and biodegradation. 9.- Extraction of 2D section to validate geometry, 2D-3D 2.- Building of structural geometry model run and maps (time ms) From previous studies, the main hydrocarbon source thermal calibration rock is represented by Navay Formation, which is constituted by La Morita and Quevedo Members, for Barinas Basin. 8.-- 3D block building (maps Geological Model 3.- Building of structural loading in the Block Build ) maps (depth) The figures 6 show the TOC variation and Ro for the Quevedo and La Morita Members. The general trends for both 7.- Constructions of 4 and 5. - Exporting, reviewing and thematic maps (TOC, editing the depth structural maps of them increase from Southeast to Northwest. kerogen index and thermal Basin Modeling in the Map Editor model) Quevedo Member 6.- Building the lithology TOC Original Maturity maps and the lithology index maps TOC (%) Ro (%) Figure 3. Methodology used for the petroleum system G analysis of the Barinas Basin using a 2D-3D Basin Modeling. H AD I Ñ J O D KA N AK AK AL AL Q Study area G Q AC F AE AM AM 10.534 Km 2 R W W X P H R X AN AF AN AG Z Y I J Ñ AH O D K L M LEGEND AI N AJ 3D Merged 3D Block P Study area 2D Seismic 10 Km Figure 4. Location map of the available seismic data (2D and 3D). PETROLEUM SYSTEM OF THE BARINAS BASIN: A 2D/3D BASIN MODELING APPROACH 3 La Morita Member TOC Original Maturity TOC (%) Ro (%) G G H H AD AD I I J Ñ Ñ J O O D K D K A A N AK NAK AL AL Q AC AC F AE Q F AE AM W WAM P X R P R AF AN X AG AF AG AN Z Y Z Y AH AH AI AJ AI AJ Figure 6 .TOC and maturity trends in the Quevedo and Morita Figure 8 Thickness variation of the Formation Paguey in the Member. Barinas Traditional Area to the North, where the red line represents the depth lines, the blue one lines in time, time lines Reservoirs and the different colors (yellow, medium and strong) (Taken The gobernador and Escandalosa Formations have been from ANKA et al, 1998).