- Home
- Conferences
- Conference Proceedings
- Conferences
8th Simposio Bolivariano - Exploracion Petrolera en las Cuencas Subandinas
- Conference date: 21 Sep 2003 - 24 Sep 2003
- Location: Cartagena de Indias, Colombia
- Published: 21 September 2003
1 - 20 of 92 results
-
-
Structural Interpretation And Source Rock Maturation Modeling Along Two Distinct Transects In The Upper / Middle Magdalena Basin, Colombia
More LessThe tectonic and stratigraphic evolution of the Magdalena Valley and adjacent areas of Colombia took place in a number of episodes. The original Jurassic back-arc extensional basin in the area has been modified during several periods of compression, oblique-slip and elevation through the late Cretaceous, and Cenozoic. A complex finite geometry has been developed, and maturation and migration histories are significantly different in different sub-areas. On two distinct geologic transverses, the structural interpretation has been studied using forward kinematic reconstruction approach allowing a depth extrapolation of the major structural blocks to be consistent with the surface geology and thermal and paleo-temperature indicators. The area of specific interest is the neighborhood of the Ibague Fault zone, a structure which almost certainly initiated during the initial back-arc rifting and which is usually taken to be the line separating the Upper Magdalena and Middle Magdalena basins. Significant Eocene elevation has occurred south of the fault; north of it a thick Cretaceous shale section reached its peak of hydrocarbon generation in the Paleogene. It was not possible to model the evolution of the local area without extending the scope of the investigation to include a couple of transects from the Llanos across the whole Eastern Cordillera. The Eastern Cordillera seems to have remained a positive area through the Cenozoic, hence its relative immaturity.
-
-
-
Modelamiento Y Análisis Estructural Del Anticlinal De Zipaquirá Y Su Aplicación A La Interpretación A Zonas De Piedemonte
Authors A.J. Lozano, W.J. Castro and R. LinaresUna de las zonas de mayor interés económico para la exploración de hidrocarburos son los Piedemontes en la Cordillera Oriental Colombiana. Definir de la geometría de la trampa es uno de los factores de riesgo debido a la deficiente calidad de la información sísmica y a la insuficiente información de pozo. Esto lleva a que los prospectos se soportan en modelos estructurales cuya viabilidad geológica se fundamenta en la geología de superficie. Se realizó un análisis 3D estructural del Anticlinal de Zipaquirá, localizado en la Sabana de Bogotá, estableciendo los mecanismos de deformación que intervinieron durante su formación. Se balancearon y restauraron seis (6) secciones transversales con datos publicados y adquiridos en campo por nosotros. Para el modelo estructural 3D se utilizaron los software Geosec® y Geographix - Discovery®. Se interpretaron pliegues tipo Detachment Folds y Fault Propagation Fol. y Lateral Ramps. El entendimiento de estas estructuras es una herramienta para explicar estructuras en el Piedemonte Llanero cuya complejidad es similar. Se propone una metodología de trabajo de modelamiento del subsuelo en zonas complejas. Se concluye que la complejidad de esta zona de cabalgamiento es producto del alto grado de deformación asociado a zonas de despegue en la Formación Chipaque y a rampas laterales perpendiculares al tren estructural regional, similares a las observadas en el área de Cupiagua y de Nuevo Mundo en los Piedemontes de la Cordillera Oriental; con esto se podría disminuir el riesgo asociado a la geometría y al sincronismo de trampa durante la exploración y producción de hidrocarburos.
-
-
-
Exploring Sub-Basement Traps In The Upper Magdalena Valley Of Colombia
Authors C. Macellari, J. Amaral, J. Salel and M. OsorioThe intramontane Upper Magdalena Basin of Colombia has been actively explored for hydrocarbons and is reaching a mature level of activity. However it has been long suspected that important oil accumulations still remain trapped in structures presently located beneath overthrusted basement rocks. Several attempts in the past were unsuccessful in testing this play concept. The basin has been subjected to several phases of active compression since at least Oligocene times, and it is encroached on both sides by inward verging thrust faults that carry basement rocks of Jurassic and Paleozoic age on top of a Mesozoic-Cenozoic sequence. During the last year, the HOCOL-TEPMA consortium drilled the deepest well to date in the basin to test the sub-basement concept. The Iskana 1A well drilled over 9000 feet of Paleozoic basement rocks and reached a final depth of 17588 feet. The objective Lower Cretaceous sandstone of the Caballos Formation was found oil-bearing close to the prognosed depth. The well encountered a lower section with heavy oil (19º API) and an upper section that produced 29º API oil at noncommercial rates. Iskana proves for the first time the validity of the subthrust play in the area. However it is still uncertain if sealing against basement rocks is an effective trapping mechanism since the structure possibly has some fourway dip closure. Similar structures remain untested along the trend, but important technical challenges need to be solved in order to make this play economically viable.
-
-
-
Modelamiento Estructural 3D Y Aplicaciones En La Exploración Y Explotación De Hidrocarburos En El Cinturón De Cabalgamiento Del Piedemonte Llanero, Cordillera Oriental, Colombia
By J. MartinezEl Piedemonte Llanero esta localizado en las estribaciones orientales de la Cordillera Oriental de Colombia. BP ha estado explorado activamente en este ambiente complejo desde 1988. La actividad exploratoria ha conducido al descubrimiento de varios campos con una gran variedad de fluidos (gas condensado muy pobre a petróleo volátil) en cuarzo arenitas muy apretadas. El estilo estructural de este cinturón plegado de cabalgamiento varia a lo largo del tren desde estructuras frontales simples a un imbricado de hasta cuatro escamas apiladas en una zona triangular. En estas áreas de gran complejidad y variabilidad estructural la calidad sísmica es pobre y por lo tanto es imperativo integrar todos los datos de superficie, subsuelo y perforación en modelos estructurales tridimensional. Este modelamiento se convierte en una herramienta esencial para entender la geometría y cinemática de los campos, la distribución y composición de fluidos, predicción de la calidad de roca, evaluación de reservas, y diseño de programas de exploración, evaluación y desarrollo. Este articulo presenta un resumen de la estratigrafía del área y de la variación de la complejidad estructural a lo largo del tren y algunos ejemplos de las herramientas de modelamiento estructural 3D que han ayudado a resolver problemas específicos (calculo de hidrocarburos in-situ en áreas de alto buzamiento y fallamiento, opciones de adición de reservas en áreas maduras y evaluación del potencial petrolífero de la cuenca).
-
-
-
Geometria Y Cinematica De Micropliegues Del Cretaceo Basal Aplicados A La Interpretación Estructural De Zonas De Piedemonte
Authors M. Murillo, C. Sarquez and R. LinaresUna de las zonas de mayor interés económico para la exploración de hidrocarburos en Colombia son los Piedemontes de la Cordillera Oriental. La definición de la geometría de la trampa es uno de los factores de riesgo debido a la deficiente calidad de la información sísmica y a la escasa información de pozo. Lo anterior lleva a que los prospectos se soporten en modelos estructurales cuya viabilidad geológica se fundamenta en la geología de superficie. Dado el comportamiento fractal de las estructuras, en este trabajo se define una relación entre las microestructuras aflorantes y las existentes en el subsuelo, de mayor escala. El afloramiento está localizado en el flanco Oeste de la Cordillera Oriental donde se exponen estratos de la Formación Murca. Se hace una descripción geométrica detallada y se analizan cinemáticamente las microestructuras, para su descripción se creó un método de proyección del afloramiento al papel, para luego ser tratadas con el software de modelamiento estructural Geosec®. Se restauraron tres secciones por área, el acortamiento del afloramiento es de 44.5 metros (12 +/- 1.2%), los esfuerzos compresivos y el contraste litológico controlaron desplazamientos a través del rumbo de las capas creando zonas de despegue paralelas a los planos de estratificación, se determinó que los plegamientos fueron causados por propagación de fallas en profundidad. Se extrapolaron las características estructurales del afloramiento a la de las interpretaciones sísmicas y modelamientos estructurales de los Piedemontes de la Cordillera Oriental, aportando una validez geológica a los modelos. Con lo anterior se disminuye el riesgo asociado a la geometría y sincronismo de trampa durante la exploración y producción de hidrocarburos.
-
-
-
The Andean Santander-Oriental Tectonic Syntaxis: A First-Order Pattern Controlling Exploration Play-Model Concepts In Colombia
Authors A. Nevistic, E. Rossello, C. Haring, G. Covellone, F. Bettini, H. Rodríguez, R. Salvay, C. Colo, L. Araque, E. Castro, C. Pinilla and C. BordarampéThe Santander and Oriental ranges form an Andean tectonic syntaxis along the central eastern part of Colombia being its internal compressive occidental compartment constituted by the more competent pre- Mesozoic (as well as the Garzon and Nevado del Cocuy massif). Easterwards this area, regarded as a spur surrounded by the arched Mid-Upper Cretaceous to Tertiary fold and thrust belt which convexity is projected towards the eastern foreland. Due to the oblique ENE Andean convergence on the Pacific border of the South American plate, the northern Santander branch - trending NNW - shows leftlateral transpressive tectonics. Contrastingly, the southern Cordillera Oriental branch - trending SSW - shows right-lateral transpressive tectonics. The interaction with the foreland exhibits a fold and thrust belt with relevant wrenching expressed by en-echelon multi-scalar structures. At present, the Mesozoic and Tertiary depocenters are dismembered by the action of this first-order pattern tectonics into several relictic isolated portions. These basin segments show different local structural geometries depending on their relationships with the major extensional pre-Tertiary as well as their Andean reactivation and inversion structures. This tectonic pattern difficults the traditional geometrical balancing of conceptual section across the entire Andean cordilleras and affects the petroleum system models improving reservoir and migration conditions of the diverse plays along the main tectonic corridors.
-
-
-
Structural Style, Sequence And Timing In The Acevedo Block: Implications For Subthrust Exploration In The Upper Magdalena Valley
Authors G. Rait, I. Dawes, T.D.J. England and G.W. PaukertThe Upper Magdalena Valley is bounded on the west and east by thrust faults that carry 'basement' lithologies: Precambrian metamorphics (Garzon Gneiss) or Mesozoic igneous and volcano-sedimentary rocks (Saldaña Fm. et al.). Many prospects drilled beneath these basement overthrusts have failed because trap geometries were not as prognosed. To improve our prognoses of these subthrust structures (and avoid becoming "Saldaña victims") we need not only better seismic imaging but also a better understanding of how the basin-bounding thrust systems evolved. The Acevedo Block lies on the eastern side of the southern Upper Magdalena basin. Subthrust prospects have been identified beneath the Garzon-Suaza fault system, which forms the western edge of the Eastern Cordillera there. Seismic, geological mapping, and thermochronometric studies show that the lowest basement-carrying thrust is relatively steep and has a small displacement, that the thrust system developed 'out-of-sequence', and that most of the structural development - on both sides of the valley - occurred during the Neogene. In addition, depth conversion of the seismic and the geology to the south show that the subthrust block is a planar, gently northwest-dipping panel >15 km across. The important result for local exploration is that the trap geometry is not an anticline beneath a shallow, fartravelled basement sheet - as would be implied by restoring a 'piggy-back' thrust sequence - but is a dipping panel that terminates updip against basement. It is possible that similar traps exist elsewhere along the margins of the Upper Magdalena Valley.
-
-
-
2D And 3D Structural Balancing In A Deformed Foreland Basin, Peruvian Subandean Belt
Authors D.R. Richards, S.J. Calvert and H. YamamotoThe Camisea area in southern Peru has yielded several large discoveries in structural traps. 2D and 3D structural modeling and balancing are key to understanding the hydrocarbon discovery potential of this area, as well as evaluating specific prospects. In order to evaluate the potential of this sub-basin for new hydrocarbon discoveries, regionally consistent and balanced 2D structural sections set the framework for 3D visualization and balancing. Well and surface data also constrained the 3D model. The process of building a 3D model enhanced understanding of the structural development and hence the hydrocarbon potential of the basin. The process began with depth converting, consistently reinterpreting and balancing lines in 2D. The reinterpreted and balanced 2D sections provided a much improved understanding of potential trap volumes. The process of building the 3D model provided insights on fault linkages, terminations and timing of deformation in the region. Map view restoration of a key horizon yielded a consistent kinematic system for the deformation. The kinematic system is in accordance with the distinct strike of the two limbs (in map view) of the fold and thrust belt. The result of the balancing, modeling and structural analysis is a comprehensive and valid 3D model of the structural history and geometry. Hydrocarbon exploration in onshore frontier basins often focuses on reinterpreting subsurface data of a below average standard. Structural balancing in 2D and 3D provide reliable input for basin modeling, as well as an understanding of the regional structural framework and geometry.
-
-
-
Thrust Kinematics Of The Tangara/Mundo Nuevo Area: New Insight From Apatite Fission Track Analysis
More LessTangara & Mundo Nuevo blocks are located in the Llanos Foothills northeast of Bogota which are mainly structured by thrust related folds. New seismic, new structural field data, and new burial computation allowed us to revise the tectono-sedimentary history of the area and to propose a new sequential deformation modeling based on balanced cross sections. Burial history of the area has been interpreted using new AFTA and new maturity data. Thicknesses of Carbonera and Guayabo Fms computed as well as measured in seismic and wells show significant E-W variations. Seismic evidences of progressive unconformities within the Carbonera Fm. underline a Pre-Guayabo structuration. This pre Midddle-Miocene deformation stage could have controlled the formation of a slightly folded belt involving Cretaceous and younger series and probably linked with an early inversion of the Lower Cretaceous rift basin. Guayabo foreland basin system appears to have been controlled by an active thrust wedge represented by the internal structures now outcropping in the Mundo Nuevo block which are consistent with a minor burial (<300 m) below the molasse sequence. Thicknesses of Guayabo Fm. (2400-1700 m.) computed in Tangara block indicate a more distal foreland environment but remain lesser that the Guayabo Fm. thickness measured in the present day Llanos foreland (3100m) which is completely overthrusted by the external fault. Because of lack of high resolution ages within the Guayabo Fm., we used the sedimentation rate to propose that this significant difference of burial indicates that the external structures were also active before the Pleistocene.
-
-
-
Evolución Estructural Del Flanco Oriental Del Valle Superior Del Magdalena Y Su Implicación En La Carga De Hidrocarburos
Authors G. Rodriguez, L. Maya and C. MoraCon base en información geológica y geoquímica, se presenta un modelo de evolución estructural para el Flanco oriental del Valle Superior del Magdalena, estableciendo su relación con la depositación de las unidades sin tectónicas y su efecto en la generación y carga de hidrocarburos. Secciones estructurales han sido construidas y balanceadas en 2D con el fin de entender la relación entre la depositación de las unidades post Eocenas y las estructuras formadas durante los diferentes pulsos de levantamiento que han afectado el Piedemonte Oriental del Valle superior del Magdalena (VSM) desde el Eoceno. La carga de hidrocarburos se basa en los análisis geoquímicos realizados a los pozos El Encanto-1 y la sección Alpujarra y su interpretación dentro del contexto de la evolución estructural del área. Del análisis geoquímico realizado al Pozo El Encanto-1 se concluye que la totalidad de la secuencia estratigráfica evaluada (Grupo Villeta y Formación Caballos), presenta rocas con potencial generador que varía de pobre a excelente respectivamente, con materia orgánica de origen marino (dinoflagelados y foraminíferos) mezclada con materia orgánica de origen continental y bajos niveles de madurez térmica. Estos resultados contrastan con los encontrados en la sección Alpujarra (en superficie) donde las Formación Caballos y el Grupo Villeta se encuentran maduras, indicando que alcanzaron procesos de expulsión de hidrocarburos. La carga de hidrocarburos para estructuras formadas durante el Eoceno (p.ej El Encanto), proviene de las partes más profundas en la cuenca para ese tiempo, ubicadas al oriente según el modelo estructural propuesto, y que corresponde a sectores como el Sinclinal de Colombia en donde la acumulación de los sedimentos sintectónicos post Eocenos permitieron que la Formación Caballos y el Grupo Villeta alcanzaran los niveles de madurez registrados en la sección de superfice.
-
-
-
Role Of Extensional Structures In The Development Of The Middle Magdalena Valley Basin – Colombia
More LessThe MMVB was developed through different tectonic stages related with the interaction of the tectonic plates at the Northwestern corner of South America. During Jurassic and early Cretaceous the MMVB went through rift stage that evolved to an aulacogen. Many of the structures related with the extensional phase of the MMVB were modified after the Tertiary tectonics, however the rift structures in the northern portion of the basin are still well preserved. The northern part of the MMVB is a monocline dipping toward the southeast that represents a half graben inside the rift. The monocline structure is dipping south-eastern, as is the direction, where isopach contours thicken. Most of the structures present at the area are normal and reverse faults of variable vergence, oriented in northeast-southwest direction. Kinematics of the rift seemed to be rotational during the syn-rift accumulation and non-rotational during post-rift sedimentation. Most of the faults remaining the rift structure were inverted after compressional tectonics that started at Late Cretaceous. According the model proposed by Hayward and Graham (1989), inversion seemed to be mild in the northern MMVB area. Transpresion caused by the oblique collision of the Western Cordillera, added a strike-slip component to the reactivation process, through the clockwise rotation of the blocks.
-
-
-
The Occurrence Of Shear-Torn Palynomacerals In Middle To Early Late Devonian Strata Of Southern Subandean Bolivia: Their Geological Significance
More LessPalynomacerals damaged by shear, displaying characteristic tension gashes (subparallel tearing pattern), are reported from Middle to early Late Devonian shales of the Los Monos Formation, in the subsurface of Southern Subandean Bolivia. Shear has affected not only marine and terrestrial palynomorphs (trilete spores, organic-walled microphytoplankton, chitinozoans) but also land-derived phytoclasts. Sheartorn palynomorphs have been previously recorded in oilproducing sedimentary basins of Brazil. Here, their origin was attributed to faulting because of the following facts: (1) the shear-torn palynomorphs were recovered from wells drilled in areas infested by growth faults; (2) they occur mainly in Albian to Paleogene strata that immediately overlie the Aptian salt, and thus are severely affected by salt tectonics; (3) the subparallel tearing pattern of palynomorphs is suggestive of deforming processes that took place when the host sediment was still in a rather plastic (partly unconsolidated) state. In the investigated Los Monos sections, several samples present a considerable proportion of the palynomacerals sheared to varied degrees. The frequency of shear-torn palynomacerals is especially high in middle to upper parts of the formation. This suggests that thrusting, faulting and other deformation processes could have affected more plastic (pelitic) strata in those intervals. Tectonic disturbances of the normal stratal succession are not always distinguished on the basis of strictly biostratigraphic evidence. However, other apparent palynological anomalies (involving abrupt changes in composition, nature and/or preservation of the organic residues) occur in different intervals of the investigated wells. Some of these match intervals where palynomorph shear becomes more frequent and intense, thus pointing out to possible tectonic controls. Other palynological anomalies, dissociated from shear-torn palynomorphs, are more probably related to faciological causes.
-
-
-
The Agrio Fold And Thrust Belt: Structural Analysis And Its Relationship With The Petroleum System Vaca Muerta-Agrio-Troncoso Inferior (!), Argentina
More LessThe structural style of the Agrio Fold and Thrust belt of the Neuquén Basin, Argentina, is characterized by = the insertion of basement tectonic wedges into the sedimentary column that deform pre-existing thinskinned triangle zones; constituting a multi-episodic orogen. Based on the revision of regional geologic data and carefull analysis of cross-cutting field relationships it can be determined that the upper limit of the beginning of the Andean deformation of the Agrio FTB, given by the extrusive rocks of the Colipilli-Cayanta Fm., corresponds to the Lower to Middle Eocene. These units are intruding and covering the previously formed structures. Other authors lower this age down to the Senonian (Upper Cretaceous) and it would be manifested by the unconformity between the Rayoso Fm and the Neuquén Group. Within the study area, the cross-cutting field relationships may lower this age up to Cerro Lisandro Mb. (88 Ma?); with another reactivation pulse at the Lower to Middle Miocene (18-12 Ma). These evidence allow to adjust the timing relationship to the critical moment of the petroleum system (Upper Cretaceous) Vaca Muerta-Agrio-Troncoso Inferior; contrarily to conclusions of previous studies that showed only one uplift event of Miocene age. The application of new structural models, together with the change in the timing relationship promotes the study of new exploratory leads for liquid hydrocarbons. Finally a new regional correlation for the Tertiary in this area of the Agrio Fold and Thrust belt is proposed.
-
-
-
Petroleum Systems And Tectono-Stratigraphic Evolution Of The Madre De Dios Basin And Its Associated Thrustbelt In Peru And Bolivia
Authors A. Aleman, D. Valasek, C. Ardiles, G. Wood, G. Wahlman and J. GrovesDespite the presence of a widespread Late Devonian world-class source rocks (up to 16 % TOC), the Madre de Dios Foreland Basin and associated fold and thrust belt is one of the most under-explored Subandean basins. Detailed biostratigraphic studies have confirmed similarities to the tectonic stratigraphic evolution of the southern Ucayali Basin. Oils and source rock correlations indicate at least three distinct source rocks. These include mixed Type I/II Devonian (Frasnian Famennian) world-class source rock, units from the Mississippian Ambo Group, and the Late Permian Ene Formation. Devonian source rocks have a variable thickness, richness, and regional distribution. Hydrocarbon generation commenced during the late Cretaceous in the deepest part of the basin and has continued to the present time at the basin margin. Several stacked Devonian and Carboniferous reservoir and seal pairs are present. Reservoir quality improves northward and eastward away from the preserved foredeep. The main migration carriers are sandstones interfingered with or overlying the Devonian source rocks. Interbedded Pennsylvanian to Permian evaporites in the carbonate sequence represent the regional seal, which stratigraphically restricts upward hydrocarbon migration Potential stratigraphic traps with good seismic amplitude anomalies are present along the Manu Arch and may also exist along the eastern peripheral bulge. Thrust loading was hindered by the crystalline Madidi Arch, which operated as buttresses for foreland thrust propagation and also inhibited faulting along the poorly developed peripheral bulge. The peripheral bulge may exhibit significant faulting and could be the site of potential structural traps as the arch plunges northwestward and turned westward. Progressive eastward migration of the oil kitchen is associated with episodic thrust sheet propagation and coeval molasse deposition. The fold and thrustbelt petroleum system is more complex and may involve younger Permo- Carboniferous source rocks. Peak oil generation took place prior to the Quechua Phase of Andean deformation in subthrust synclines kitchens. As a result, most of the structures are charged with gas and condensate. North of the Madidi Arch, there is potential for additional oil kitchens in subthrust synclines. Because of the complex duplex style, large thrust displacement, and intricate paleo-burial history documented in the Candamo-1X well, reservoir quality is a crucial issue for liquid hydrocarbons. However, reservoir quality may improve north of the Madidi Arch where is preserved along the frontal thrusts that carry older units in the hanging wall. Good pressure seals in the Cretaceous Chonta Formation and Lower Tertiary shales are also documented in the Candamo-1X discovery as well as in the Camisea trend.
-
-
-
Petroleum System Characterization, Sinu Area (Offshore, Colombia)
Authors J. Amaral, N. Crepieux, D. Levache, E. Cauquil, B. Mouly and C. OsorioDuring the last decades different oil companies have evaluated and explored the petroleum potential of the offshore Colombian Caribbean margin (Atlantic Ocean). The last evaluation campaign was performed by Total during 2001 and 2002 by integrating the most recent available technologies and techniques to acquire and interpret data on deep waters (400-3000 m water depth) of Sinu block. The petroleum system study on the Sinu area was focussed on the determination of a possible hydrocarbons generative system (presence and extension) and on the prediction of fluid quality (origin & maturity) inside of the prospects. The characterization study of Sinu block was carried out in several steps: 1. Integration of available 2D seismic data and acquisition of bathymetric campaign in the area to optimize the coring measurement points in the area. Figure 1 - Location of Sinu Area 2. Acquisition and data analysis of heat flow measurements and seabed piston coring to characterize the present conditions and sampling the hydrocarbon shows. 3. Integration of data results and run of basin modeling using 1D (Genex) and 2D (Temis) to characterize the extension, timing, maturity and the petroleum systems in the area. The referred studies put in evidence the existence of a generative Tertiary gas petroleum system in the offshore area. A Cretaceous oil prone system remained hypothetical in the Sinu accretional prism. The seal prospect efficiency appears to be a critical point for the prospectivity in this area, considering the mud diapirism and overpressures.
-
-
-
Cuencas Sedimentarias De Brasil: Reevaluación De Los Sistemas Petrolíferos Y Perspectivas Exploratorias Futuras
Authors R. Bedregal, F. Gonçalves and G. BacoccoliCon cerca de 5.000.000km2, el área sedimentaria de Brasil es la más grande de Sudamérica. De las 29 cuencas sedimentarias del país, 8 poseen producción comercial de aceite y/o gás, 10 presentan acumulaciones no-comerciales de petróleo, y 11 no han presentado evidencias confiables de la existencia de hidrocarburos. A pesar de la cantidad y variedad de áreas disponibles, las compañías petroleras que han ingresado en el país desde el fin del monopolio estatal en 1997 están concentradas en prácticamente sólo las cuencas de Campos, Santos y Espírito Santo, ubicadas en la margen continental sureste y consideradas como las de mayor potencial en Brasil. Sin embargo, a pesar de las grandes expectativas en estas tres cuencas, (particularmente en aguas profundas), en los últimos 6 años no han sido descubiertas acumulaciones de petróleo compatibles con las expectativas de las compañías extranjeras. Veintisiete sistemas petrolíferos fueron definidos, reevaluados y comparados en este estudio de todas las cuencas de Brasil. El análisis de los datos disponibles sobre los elementos y procesos de los sistemas, permitió identificar los principales factores de riesgo de cada cuenca sedimentaria y definir las tecnologías que deben ser aplicadas para obtener un mejor entendimiento de estos factores. Son discutidas las perspectivas exploratorias de las cuencas onshore y offshore de Brasil.
-
-
-
Sistema Petrolero Terciario Pagüey- Pagüey Inferior (!) En La Sub-Cuenca De Guarumen, Venezuela
Authors H. Belotti, G. Conforto, J. Silvestro, J. Rodriguez and P. KraemerLa actividad exploratoria realizada por Pecom Energía S.A. (hoy Petrobras Energía S.A.) en los últimos 6 años en la Subcuenca de Guarumen en la Región Centro - Oeste de Venezuela permitió comprobar la presencia de gas en la Fm Pagüey Inferior. La columna estratigráfica consta de un basamento ígneo - metamórfico infrayaciendo a clásticos marinos de margen pasivo depositados en el Paleoceno - Eoceno Inferior. La sedimentación continuó en el Eoceno Medio y fue controlada por un régimen extensional de tipo antepaís fracturado. Durante el Eoceno Superior - Oligoceno Inferior se depositaron secuencias clásticas procedentes del frente montañoso situado al norte bajo un régimen de antepaís flexural. Posterior a los depósitos neríticos del Oligoceno Superior - Mioceno Inferior la región fue sometida a esfuerzos compresivos ligeramente oblicuos a las fallas extensionales preexistentes, reactivándolas y formando estructuras compresivas generando una faja de interés prospectivo paralela al frente de la Cadena Caribe. Esta faja fue evaluada con dos pozos los cuales probaron la presencia de gas termogénico seco en areniscas cuarcíticas fracturadas de la Fm. Pagüey Inferior. Se considera roca madre a las lutitas marinas de la Fm. Pagüey del Eoceno Medio (Querógeno Tipo II y II/III). La generación y migración hacia las estructuras anticlinales se asocia con el emplazamiento de la carga tectónica durante el Mioceno Medio. Se propone la existencia en la Subcuenca de Guarumen de un sistema petrolero Terciario Pagüey - Pagüey Inferior (!) cuyo potencial es principalmente gasífero.
-
-
-
Hydrocarbon Habitat In Southern Ucayali Basin, Perú
Authors I. Brisson, M. Ayala, L. Anzulovich, O. Jofre, S. Corsico and S. SciamannaWe revisited the stratigraphy, structure and petroleum geology over an area of about 60,000 km2 in the Ucayali basin, Peru, integrating the work minutely done during the last years over a region that was once perceived as one of the most promising sub-Andean basins after the giant Camisea discovery. This paper presents the integration of the analysis on biostratigraphy, sedimentology, geochemistry and wells, along with a pervasive mapping over compiled, reprocessed and acquired seismic that allowed us to reconstruct the pretty complex geological history of the study area that ranges from the early Paleozoic to the late Tertiary. Three proven and one speculative petroleum systems are present in this basin: the oil prone Jurassic/Cretaceous system - restricted to the north -, the gas/light oil prone early Carboniferous -Paleozoic system, the oil prone early Permian- Paleozoic/Cretaceous system and finally the speculative Devonian-Paleozoic system. We performed 1D, seriated 2D and a 2½ dimension basin modeling to address the main processes controlling the efficiency of the Ucayali petroleum system, investigating the relations between startigraphic, tectonic overburden and the viability of long lateral versus short hydrocarbons migration mechanism. We analyzed the petroleum occurrences and the prospect failures to characterize the main play concepts of the Andean front and the basin border to determine the critical play element in the area and highlight the future exploration potential of the area.
-
-
-
Hábitat De Hidrocarburos En El Pie De La Sierra De La Faja Corrida Subandina, Cuenca De Tarija. Area De Santa Cruz, Bolivia
Authors C.E. Cruz, C. Mombrú, A. Cangini, C. Seguí and J. ContiThree previously unproductive reservoirs in the region lying between the Parapetí River and the Santa Cruz de la Sierra city, have recently been successfully tested by Pluspetrol S.A. The tectonic setting of these gas discoveries is the Foothills of the Subandean Thrustbelt of the Tarija Basin. The Tajibos success is a four-way closure anticline linked to the Emergent Thrust Front where the gas is lodged in the lowermost Tertiary Petaca fluvial sandstones. The Tacobo gentle ramp related anticline, produced outstanding gas rates from Lower Devonian Huamampampa fractured quartzite sandstones. The latter trend bears a notable amplitude anomaly but in a different structural level. There, the Curiche well tested gas from Tertiary Chaco fluvial ephemeral sandstones. The Río Seco structure is a fault propagation fold with a gas accumulation in the Upper Carboniferous Escarpment peri-glacial fluvial sandstones, discovered by YPFB in past decades. Non-commercial gas was tested here from Mid Devonian Iquiri shelf stormy sandstones. The gases form a group that has similar characteristics with minor differences that have been interpreted to be generated by the same source rock section, according to geochemistry evaluation and gas isotope data. Faults are considered to be the main migration pathway, since the hydrocarbons are trapped in different reservoirs and structural levels. During the last four years, the use of technology and 3D seismic as key elements of an important exploratory effort, led to the discovery of these gas accumulations that amount almost 1 TCFG recoverable reserves.
-
-
-
Áreas Con Mayor Potencial De Carga De Petróleo: Cuenca Valle Medio Del Magdalena (Vmm) Y Occidente De La Cordillera Oriental, Colombia
More LessSe ha establecido que sectores con mayor probabilidad de carga de petróleo están asociados a la franja más oriental de la Cuenca del VMM y el Piedemonte Occidental de la Cordillera Oriental, allí los procesos de entrampamiento de crudo estuvieron favorecidos por el sincronismo entre la expulsión de petróleo y los principales eventos de formación de trampas. Esta relación temporal no se observa en otros sectores de la cuenca VMM. Complejas y variadas historias de transformación de la materia orgánica son reconstruidas para sectores de la cuenca que muestran significativas diferencias en los patrones de enterramiento y en las historias termales de sus rocas fuente. Los resultados, obtenidos a partir de simulaciones en 14 pozos pseudo pozos, permiten cuantificar el volumen de crudo generado, estimar los volúmenes de crudo remanente y localizarlos temporal y espacialmente dentro del desarrollo estructural de las áreas. La mayor parte de los hidrocarburos encontrados en el centro y oriente de la cuenca corresponde con crudos de alta evolución termal y poco degradados, expulsados desde la Formación La Luna en zonas de piedemonte. Sin embargo evidencias moleculares demuestran que estas acumulaciones son mezclas con aportes menores de hidrocarburos desde de las Formaciones Paja y Tablazo. Los yacimientos al norte y occidente del VMM estarían más relacionados con crudos generados desde rocas del Cretáceo Inferior y algunos migrados del borde oriental de la cuenca; en estos sectores la Formación La Luna no alcanzó la madurez necesaria para generar y expulsar volúmenes suficientes de crudo.
-