Research On Fluid Unit In Tight Gas Sandstone Of Sulige Gasfield

Gas is the conventional energy resources, while tight sandstone gas can be classified asunconventional gas resources, but people still have different opinions. The recoverable resourcesof tight gas sandstone in Chinese is calculated to be9.4×1012m3, which will be the focus offuture research. The researchers have conducted the research on the geology feature, gas-bearingproperty and recovery schemes after discovering the Sulige gas field, including the analysis ofreservoir flow properties. The division of flow units can lead a deep understand of formationheterogeneity, and give a correct judgement to reservoir properties and flow properties, as wellas propose some reasonable suggestions to oilfield development. In addition, the flow units alsohave a certain guiding significance on production and application, such as the well location andflood pattern modification, the prediction of production performance, the calculation ofindividual well producing rate and the prediction of residual oil distribution.In this paper, the reservoir of He8is divided into four categories by using the mercurypenetration, relative permeability, thin slice, NMR and well log data. First, analyze the micropore structure characteristics and liquidity of different reservoir, then combined with three-watermodel to achieve the characteristic parameters, which reflect the reservoir physicalcharacteristics, effective porosity, pore space and filtration capacity. After that, based on thePSO-SVM to realize the division of flow unit, we establish a set of logging evaluation softwarefor tight gas sandstone, which has great theoretical significance and economic benefit. At last,with the research of sedimentary facies, through comparing the result of interpretation of flowunit with capacity and gas result in this interval, we process a reasonable verification.When prepare the logging data, well top data, fault data of Sulige, we build a structural model,and based on this structural model we simulate the distribution of interwell flow units, known asflow unit facies. Assigning the mesh by use the flow units as a constraint condition, then wefinally obtain the distribution of porosity and permeability with Sequential Gauss simulationmethod, and build a petrophysical modeling, which can reflect the formation heterogeneity.In this paper, we introduce the PSO-SVM method to predict the flow units, and use therock-fluid quality as the parameters in the division of flow units to reflect the seepage ability ofpore, which improving the calculation precision and speed. Based on the study of flow unit, weobtain the3D geological model in Sulige, which is an extension of flow units.