Geological Characteristics And Development Effects Evaluation In The East Of Z Oilfield In Venezuela

Z oilfield is located in the eastern Venezuela, which is an old and marginal oilfield with60years of development history. Through the fine reservoir description technology, based onsedimentary geology, structural geology and petroleum geology theory and combine withprofessional techniques such as seismic and logging to carry out the stratigraphic sequencedivision, and on this basis, through the seismic calibration, to explain the fracturecharacteristics and tectonic features. On the basis of predecessors’ research results and coringdata, to give a detailed description of the sedimentary characteristics and reservoircharacteristics in this area, the research suggested that the deposition type in this area ismarine delta deposition, and lithology is mainly medium and coarse sandstone, with moderateheterogeneity and common reservoir physical property, it is an reservoir with low-mediumporosity and high-medium permeability. By systematic analysis and research, describe thelongitudinal and plane distribution of oil layers, and emphatically study control factors of thereservoir. After the systematic geological research above, display the geological researchresults by three-dimensional geological modeling technique.In order to service for oilfield development better, a detailed geological research isnecessary. In current, there are only52oil wells and5gas injection wells are developedamong368wells in this oilfield, it’s in development condition with low speed and production,and has been faced with series of problems such as huge numbers of reservoirs, high reservesproducing degree, low formation pressure, poor well conditions and deep heavy oil forextracting, limited reservoir, new wells and high operation costs. Through works of naturalenergy evaluation, pressure level evaluation, decline rate evaluation and secondary productioneffect evaluation, to better understand the overall reservoir development effect, and providethe theory basis to the further targeted development for increasing production.