AB - ABSTRACT: The Patia basin is an exploration frontier area of approximately 5000 km (super 2) located in southwestern Colombia. Seventy samples from 6 outcrop sections and one oil sample from the Matacea Creek seep were submitted for geochemical analyses. These analyses provide a basis to better assess the petroleum potential of this frontier area. Organic carbon content and Rock-Eval pyrolysis indicate that the Chapungo Sequence of Late Cretaceous age and the Chimborazo Formation of Eocene age have the higher petroleum source potential among the studied units. Petrographic evidence suggests that the heat effect of igneous intrusions account for the high maturity of some of the sampled intervals. Bulk and molecular parameters indicate that the oil sample of the Matacea Creek seep has been biodegraded, but there is also evidence of a recharge of the oil to the surface. Biomarker data indicates that the Chimborazo Formation is the unit that displays the best correlation with the Matacea Creek oil. The lack of a perfect match between the oil seep and the Chimborazo extracts might be the result of biodegradation or the existence of more proximal facies of the Chimborazo Formation, not sampled in this survey. The Matacea Creek oil seep is proof of a petroleum system.
AB - ABSTRACT: Current trends of computational tools in the upstream of the petroleum industry are presented herein. Several results and images obtained through commercial programs and through in-house software developments illustrate the topics discussed. They include several types of problems and programming paradigms. Emphasis is made on the future of parallel processing through the use of affordable, open systems, as the Linux system. This kind of technologies will likely make possible new research and industry applications, since quite advanced computational resources will be available to many people working in the area.
AB - ABSTRACT: The natural processes that generate petroleum accumulations in a sedimentary basin require several ingredients: (1) the petroleum system elements: source, reservoir, seal and overburden rocks, which are the result of sedimentation processes in a subsiding basin; (2) petroleum traps, which in many cases are the result of deformation and (3) heat to convert suitable organic matter into petroleum. Although these different phenomena, are considered independent at the scale of an oil field, at the lithosphere scale (1) thermal phenomena, (2) vertical movements of the earth surface responsible for sedimentation and erosion; and (3) tectonic deformation are not independent phenomena, they are intimately related by physical quantitative laws. These mutual inter-relationship are useful in petroleum exploration to predict one factor having knowledge of the others. Applications of these concepts can contribute to understand the tectonic history of complex areas, such as the Colombian sedimentary basins, and reduce exploration risk.
AB - ABSTRACT: A total of twenty oil samples from the Orito Field in the Putumayo Basin at the South of Colombia were analyzed to define the genetic relationship of the hydrocarbons produced from the Caballos and Pepino Formations, to establish the compartmentalization in the reservoirs of the Caballos Formation, so as to study the phenomena that caused the compositional changes of crude before and after the production. The samples were analyzed for bulk parameters, whole oil gas chromatography, light fraction gas chromatography, biomarkers and carbon isotopes. The results are presented using star diagrams, crossplots, cluster diagrams and iso-value maps. It was found that the compositional differences of the produced hydrocarbons from the Pepino and Caballos Formations are produced by the fact that the crude were originated by different source rocks each one with different grades of thermal maturity. There were defined two compartments: North Dome and South Dome for the Caballos Formation reservoir. The compartmentalization is caused by faults that play a role when the trap was filled. They have acted as partial seals isolating the different sectors and causing heterogeneity in the crude composition. The integration of this geochemistry information with the static and dynamic models of the reservoir lead to define different sectors to guide the simulation study of the field. Also some sectors of interest have been identified to carry out development new drilling opportunities in the North Dome.
AB - ABSTRACT: Large amounts of oil reserves are contained in naturally fractured reservoirs. Most of these hydrocarbon volumes have been left behind because of the poor knowledge and/or description methodology of those reservoirs. This lack of knowledge has lead to the nonexistence of good quantitative models for this complicated type of reservoirs. The complexity of naturally fractured reservoirs causes the need for integration of all existing information at all scales (drilling, well logging, seismic, well testing, etc.) to provide a reservoir description for such reservoirs. This paper presents an overview of recent advances in naturally fractured reservoir modeling, which were developed to characterize the dual porosity system and to improve hydrocarbon recovery. Two techniques, material balance and numerical simulation, are shown to be supportive of one another. The material balance technique is a good tool for history matching of production performance and defining the system, which is then used as input in the numerical model. However, material balance has significant disadvantages when it comes to prediction, which is the domain of numerical simulation modeling. We present the application of a recently introduced material balance equation based on a dual-system approach. In numerical simulation, the mathematical model to predict fluid flow in anisotropic media is enhanced by using permeability tensors. We also discuss a technique to construct permeability tensors from seismic, well log and well test analysis.
AB - ABSTRACT: Postreatus was grown in a soil mixture contaminated with anthracene, wheat bran I and compost, in varying combinations. Assays with added bacteria and reinoculation of the fungus were also included. The results indicated that in many of the combinations, most of the anthracene was removed at the earliest sample time, 15 days. The most effective combination was spiked (anthracene-added) soil, fungus and compost and the addition of acclimated bacteria to this mixture inhibited anthracene removal. Analyses of extracts by high-pressure liquid chromatography (HPLC) indicated that-anthraquinone, was the major metabolite formed. The results of this study indicate that solid-state fermentation of anthracene-contaminated soils using P. ostreatus in combination with wheat bran and compost additives can produce an accelerated rate of biological removal of anthracene from the soil.
AB - ABSTRACT: Most of the mathematical models that describe the conversion of kerogen into petroleum are based on the formulations of first-order kinetics. Although the application of such models requires the knowledge of the kinetic parameters (activation energies and frequency factor) of the kerogen, the usual practice in basin modeling studies is to use kinetic data of standard kerogen types (I, II, or III) when measured data are not available. In this study, Rock-Eval pyrolysis under different heating rates and numerical optimization techniques were used to determine the kinetic parameters of Cretaceous and Tertiary source rocks of the Upper Magdalena and Llanos basins. The obtained kinetic parameters revealed a significant variability, which appears to be unrelated to the kerogen type classification based on hydrogen and oxygen indices. Modeling exercises under a constant heating rate (1.25 degrees C/M/y., 274.5K/M.y.) using the measured kinetic data indicates that kerogen conversion of organic facies with distinct kinetic parameters may be out of phase by 20-30M.y. Therefore, petroleum generation and expulsion history might be longer and more complex than if the kinetic behavior of these rocks was considered homogeneous. These differences are critical in defining the timing between petroleum generation an trap formation/destruction, particularly in the case of the Colombian sedimentary basins, characterized by a highly complex tectonic evolution.
AF - AUTHOR AFFILIATION: Repsol-YPF, Englewood, CO, United States
BK - BOOK TITLE: In: American Association of Petroleum Geologists 2001 annual meeting.
BA - BOOK AUTHORS: Anonymous
SO - SOURCE: Annual Meeting Expanded Abstracts - American Association of Petroleum Geologists. 2001; Pages 218-219. 2001.
PB - PUBLISHER: American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists. Tulsa, OK, United States. 2001.
CP - COUNTRY OF PUBLICATION: United-States
PY - PUBLICATION YEAR: 2001
CN - CONFERENCE INFORMATION: American Association of Petroleum Geologists 2001 annual meeting. Denver, CO, United States. June 3-6, 2001.
LA - LANGUAGE: English
AB - ABSTRACT: Regional analysis and structural transects reveal five distinct structural domains which are useful as exploration tools and for devising consistent tectonic and temporal sequences along the trend. These give insights into markedly different exploration potentials. 1) Deformational Front: Buried under Tertiary cover, this trend contains the widely recognized approximately 3 BBOE Cusiana-Cupiagua complex developed in the last approximately 10 years. 2) Mountain Thrust Front Domain: Consisting of mainly eroded upper Cretaceous exposures, this trend has limited potential. 3) Subthrust Domain: In just the last approximately 6 years, well over 1 BBOE may have been revealed within the giant inverted and imbricate structures that lie beneath and near the Mountain Front. 4) Outer Cordillera Domain: Consisting of mainly highly eroded lower Cretaceous exposures, this trend has very low potential. 5) Inner Cordillera Domain: It is clear that this area is not simply the eroded "cooking pot" engrained in conventional thinking, but rather demonstrates a wide range of geologic conditions--possibly from "giant-making" to "disaster" potential. Although the conventional view for HC-charge has been a 2-pulse Paleogene & Miocene model from Cretaceous-only source rocks, it is now clear that both Cretaceous and Tertiary sources charged very young Late Pliocene and Pleistocene structures (5-0.5 m.y.) with world-class volumes--a major point with multiple implications for both the Foothills and the Cordillera. Exploration pitfalls vary by domain, but include drilling structures that are mistaken for thrust anticlines, structures insufficiently inverted, "upper deck" imbricate stacks that are mistaken for deeper structures, reservoirs breached to outcrop and velocity pull-ups.