Font Size: a A A

Wuliyasitai Depression Sandy Conglomerate Reservoir Transformation Theory And Application Of Technology

Posted on:2007-08-29Degree:DoctorType:Dissertation
Country:ChinaCandidate:C B LvFull Text:PDF
GTID:1110360185473171Subject:Oil and gas field development project
Abstract/Summary:PDF Full Text Request
Consisting of gravell, sand gravell, medium-coarse-grained sandstone and clay etc., Wuliyastai Depression in Erlian basin is a typical grit frame reservoir, where gravell and sand gravell are dominating. Being characteristic of rapid changes of fades, great variability of lithology and permeability, low porosity and permeability, poor separation and connectivity as well as serious heterogeneity and anisotropy, it belongs to low porosity and low permeability sand-gravell reservoir and the majority of the oil wells can be brought into production only after the stimulation. Formation stimulation techniques, therefore, are especially important for the exploitation of Wuliyastai Depression and further study is necessarily to be conducted, as it is relatively fewer.Based on the fracturing pre-assessment and pre-analysis, study on adaptability of systematic fracturing, filtration characteristics research of fracturing fluid and optimization of fracturing etc., an integrated stimulation technology for Wuliyastai Depression is determined in this paper and it provides a technology support as well as a technical means for the exploration of Wuliyastai Depression in Erlian basin. To meet the demand of reservoir stimulation and focused on the systematical and deep researches on the selecting wells and formations for fracturing, fracturing design, stress profiles and fracturing fluid system, the main achievements obtained in this paper are as follows:(1) A quantitative analysis model of post-fracturing response prediction is established and the major influencing factors as well as the effects are discussed.(2) A numerical simulation model of systematic fracturing is present and corresponding reasonable scale of fracturing as well as fracture parameters are determined through abundant numerical calculations and optimizations of different systematic-fracturing project for the pre-production well group.(3) Considering various factors, a dynamic filtration experiments are conducted and the dynamic filtration characteristics of the fluid is experimentally analyzed. Based on the experiment results, a new mode for calculating fluid-loss velocity, with a leakoff coefficient related to the time, is put forward.(4) With fuzzy mathematics and neural network theory, a quantitative model of selecting well and layer is developed as well as a new method to optimize operational wells and layers, parameters and program.(5) Based on the laboratory experiments of rock mechanics and integrated static mechanical parameters with the dynamic, the stress profile is determined a new computing method for in-situ stress by reversion with log information and primary fracturing information.(6) Low polymer fracturing fluid system, with characteristics of little residue, low friction and filtrate loss, being easy to flow back, is developed.The above contents are deeply studied in this paper, where some are the key techniques for improving the fracturing effects and some are the problems for solve urgently during sand-gravell reservoir stimulation. With the researches in this paper, a reasonable stimulation technology for Wuliyastai Depression is primarily formed and following conclusions are obtained:...
Keywords/Search Tags:sand-gravel reservoir, hydraulic fracturing, selecting well and layer, rock mechanical parameter, stress profile, filtration
PDF Full Text Request
Related items