| Jingbian gas well is one of the four blocks of the Changqing Oil field is a typical "low porosity、low permeability and low abundance" oil reservoir.The region is a low permeability reservoirs, natural production can not reach commercial oil and gas flow requirements, reservoir fracturing transformation has become the most effective stimulation. The fracturing effect directly affect the gas well production, therefore, a reasonable assessment of the effectiveness of fracturing is particularly important.After60years of development, fracturing has gone through a stage of exploration, research, development, gradually become a mature technology, more and more low permeability reservoirs has development with the extension of time, forming a strong demand market. From the technical point of view, fracturing from a single means of stimulation become a comprehensive technological system that combining with the oil and gas exploration, reservoir protection and transformation, production engineering, fracturing occupies an important position in the oil and gas exploration and development. The evaluation was based on the success rate of the fracturing, optimizing fracturing technology, improve the production. In accordance with scientific procedures and methods, the analysis and evaluation of fracturing from the perspective of the system provide the basis for optimize fracture design and reservoir management decisions. Fracturing evaluation have a significant role in promoting fracturing technology development and the efficient development of oil and gas reservoirs, a lot of research carried out in domestic and international oil and gas fields. Fracturing evaluation techniques is one aspect of fracturing technology, but at the same time fracturing evaluation independent of the fracturing technology. The development of many dense and super dense gas reservoir relies on the implementation of the hydraulic fracturing technology, The necessity and economy of the fracturing making people aware of the need to improve the fracturing design capacity and the analytical capacity to optimized the fracturing. The fracturing of oil and gas wells is a complex engineering systems, to make an objective evaluation of these fracturing process will ultimately decide the quality and effectiveness, so the evaluation is very important. Fracturing system has a multi-goal, multilevel nature, dynamic, incomplete information and other features make fracturing evaluation become a complex and difficult problem. There are many fracturing evaluation methods, meanwhile forming the corresponding means of supporting technology. The fracturing evaluation can be divided into broad and narrow ones, the narrow one means to evaluate the fracturing by production, including the stimulation ratio, validity, cumulative increase in production etc. index; the broad fracturing evaluation is a comprehensive, integrated assessment, the index is no longer confined to stimulation ratio, but also including dynamic monitoring of the fracturing, crack geometry parameters, coincidence rate and productivity analysis etc. In the evaluation of the technical aspects, the exiting of technology including near wellbore test methods、dynamic monitoring of the fracturing、fracturing recovery test and production data analysis methods, the evaluation target Is wellbore pollution、crack geometry parameters、fracture conductivity and increased production。Testing method mainly including gamma ray logging、self-potential logging、acoustictime logging, through these logging methods and test data analysis, provide the basis for the analysis of factors affecting the fracturing and fracturing layer selection; the main target of dynamic monitoring is the geometric parameters of the crack; pressure buildup test and analysis of production data mainly refers to well test analysis method, deliverability analysis method etc, this technology to make the evaluation of the crack geometry parameters, conductivity etc。This thesis is based on statistics and analysis of the basic geological information of Jingbian gas well in Changqing Oilfield, the morphological characteristics of the well test curve, the morphological characteristics of the Fracturing curve, correlation of the basic data, analysis of factors affecting the fracturing effect and fracturing selected layer, the forecast of Fracturing, the design of the crack geometry parameters and well test data to evaluate fracturing effect of the low-permeability well etc, and confirmed the feasibility of this method by a large number of examples, ultimately forming a set of method that guidance fracturing design and evaluation of the fracturing, solve the problem of low-permeability reservoirs evaluated fracturing by production data, laid a good foundation for the rational development of the Jingbian gas reservoir。 The thesis has achieved the following achievements:1. Statistical analysis of the basic geological information:analyzed Jingbian82(148wells,374layers)basic geological parameters, Confirming Jingbian gas well reservoirs is low porosity、low permeability and low abundance, and the reservoir has strong heterogeneity。2. correlation analysis:we can get the correlatio of well logs and production、skin、fracture half-length、permeability by statistical analysis of a lot of basic data.3. analysis the factors of affecting the fracturing:we can get the degree of association sort table by correlation and gray correlation methods, and provide a basis for future fracturing layer selection.4. the design of fracturing program:according to the dimensionless production time and the crack half-length to determine the relationships of fracture half length, conductivity and permeability, then choose the right combination of fracture parameters based on production requirements; select the appropriate proppant according to the requirements of the permeability, according to the trail ing of the proppant identify the volume of proppant, then choose the rational fracturing fluid to complete t the design of fracturing program。5. the evaluation methods of low penetration wells:the traditional evaluation of the fracturing was just to evaluate the production, higher production means the better fracturing effect, but such method has one-sidedness. We can obtain the well test parameters by the test data of the recovery phase, then comprehensive evaluation fracturing effect by production、fracture half-length, skin factor and permeability.6. example analysis:verify the feasibility and reliability of our analytical methods by a large number of instances.7. comprehensive evaluation:we can get the correlation of well logs and production、skin、fracture half-length、permeability, and the method of well test data to evaluate fracturing effect, ultimately forming a set of method that guidance fracturing design and evaluation of the fracturing,... |
PDF Full Text Request