Development Index Forecasting Research In Volcanic Gas Reservoir Of The Yingcheng Group In Xushen Gas Field

Volcanic gas reservoir has been put into production in Xushen gas field from 2004. Shengshen2-1 and Xushen1 have been developed comprehensively until 2007 and 2008. There are some problems such as big differences between gas well productivity and dynamic characteristics, complex effect factors and difficult production forecasts in volcanic gas reservoir development. To ascertain production ability of volcanic gas reservoir stably, and to ensure gas supply smoothly, this paper ascertains the main influence factors of gas well productivity and dynamic characteristics from analysis of gas well productivity, behavioral characteristics and gas flow patterns of well control areas, combined with reservoir development characteristics and space types of volcanic gas reservoir. Different types of gas well development index prediction models are determined by combining unstable well testing technology with modern production dynamic analysis technique. These models fit the whole process of gas well production history. On this basis, volcanic gas reservoir development index prediction is carried out, and characteristics of development index are evaluated systematically between different types of gas wells in Xushen gas field. It also gives overall prediction and evaluation on development index in Xushen1 and Shengshen2-1 blocks, and puts forward reasonable gas supply pattern and scale for Xushen gas field.Because the development of volcanic gas reservoir is very complicated, it is difficult to determine production change and influencing factors. The conventional or single gas reservoir development index forecasting method is not suitable for volcanic gas reservoir. Xushen gas field is the earliest development of domestic volcanic gas reservoir, and there is no development index change data of actual volcanic gas reservoir home or abroad recently. The research shows that the technique that combining unstable well testing technology with modern production dynamic analysis proposed is effective methods for early development index prediction in development of volcanic rock gas reservoir in this paper. The research result is directly applied in projects such as reasonable production proration, development planning, build production scale argumentation and gas field development adjustment in Xushen gas field. It provides scientific and efficient support for Xushen gas field development.