ABSTRACT: Sequence Stratigraphic Evolution of the Oficina Formation, Eastern Venezuela Basin: Depositional Systems and Sand Body Geometry in a Non-Marine to Estuarine Environment

Zhunzhong area Qingshui River group has top and bottom boundaries,which are not clear,and research on the evolution of the lack in sequence stratigraphic framework of deposition and on the reservoir sand body types do not have a clear understanding problem.In seismic interpretation, core description and based on the analysis of the related test,combining with the mud logging and well logging data,for the redefinition of Qingshui River group on the top and bottom boundaries,it identifies 6 time significance of sequence boundary,taking Qingshui River group can be divided into 2 sequences, 5 system tracts;clear and definite the study area mainly developed delta lacustrine depositional system,which can be further divided into the delta front subfacies, beach bar facies and semi deep lake subfacies. It takes an analysis on the sedimentary characteristics and distribution rules of different types, and it controls effect of topography and hydrodynamic conditions on deposition system, and then puts forward the corresponding sedimentary patterns.

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Sedimentary Microfacies Analysis of Xingbei 1-3 Zone in Daqing Oilfield

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.734-737.436 ◽

2013 ◽

Vol 734-737 ◽

pp. 436-439

Author(s):

Bai Quan Yan ◽

Xue Jing Ma ◽

Li Hui Yuan ◽

Gui Pu Jing

Keyword(s):

Spatial Distribution ◽

High Resolution ◽

Microfacies Analysis ◽

Residual Oil ◽

Body Type ◽

Sequence Stratigraphic ◽

Stratigraphic Framework ◽

Sand Body ◽

Sedimentary Microfacies ◽

Oilfield Development

Putaohua reservoir is the principal producing formation in Daqing oilfield Xingbei block. The spatial distribution of single sand body is particularly important for the residual oil tapping in the middle-late stage of oilfield development. The paper studied sedimentary microfacies of Putaohua reservoirs in the zone, established high-resolution sequence stratigraphic framework of the area and a typical single sand body logging phase mode on the basis of logging features, finely portrayed single sand body type and spatial distribution on this basis to lay the solid geological foundation for oilfield subsequent residual oil tapping and provide a scientific geology guide.

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TOWARDS AN EFFICIENT EXPLORATION FRONTIER: CONSTRUCTING A PORTFOLIO OF STRATIGRAPHIC TRAPS IN FLUVIAL-LACUSTRINE SUCCESSIONS, COOPER-EROMANGA BASIN

The APPEA Journal ◽

10.1071/aj01008 ◽

2002 ◽

Vol 42 (1) ◽

pp. 131

Author(s):

T. Nakanishi ◽

S.C. Lang

Keyword(s):

Net Present Value ◽

Spatial Arrangement ◽

Mean Value ◽

Seismic Survey ◽

3D Seismic ◽

Sequence Stratigraphic ◽

Depositional Systems ◽

Efficient Exploration ◽

3D Seismic Data ◽

Eromanga Basin

In the Cooper-Eromanga Basin, the future of exploration lies in identifying an appropriate exploration portfolio consisting of stratigraphic traps in structurally low or flank areas. A variety of stratigraphic trap prospects in the Moorari and Pondrinie 3D seismic survey areas are identified in the Patchawarra, Epsilon, Toolachee and Poolowanna formations. To identify the stratigraphic traps, an integration of sequence stratigraphic concepts applied to non-marine basins and advanced 3D seismic data visualisation was employed. This paper focusses on estimating the chance of geologic success and the probabilistic reserves size for each prospect within its sequence stratigraphic context (lowstand, transgressive or highstand systems tracts). The geologic chance factors for an effective stratigraphic trap include reservoir, top seal, lateral seal and bottom seal within each depositional systems tract, the seal effectiveness of the adjacent depositional systems tracts and the appropriate spatial arrangement of these factors. The confidence values for the existence of geologic chance factors were estimated according to the distributions of the possible reservoir and seal rocks within each genetic-stratigraphic interval and the chance of geologic success of each prospect was calculated. For probabilistic reserves estimation, geologically reasonable ranges were estimated for each parameter employing Monte Carlo simulation to calculate the reserves distribution. When a series of possible exploration portfolios, including single or multiple prospects from the prospect inventory are plotted in terms of the chance of geologic success vs. the mean value of the reserves estimate, an efficient exploration frontier emerges. The portfolio candidates on the efficient exploration frontier were assessed with regard to chance of economic success and expected net present value (ENPV) using a simple cash flow model. The results indicate that appropriate portfolios include multiple prospect exploration especially with lowstand systems tract plays using single or multiple exploration wells. The portfolio construction approach for stratigraphic trap exploration should ultimately be made consistent with conventional play types, to enable an assessment of all exploration opportunities.

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