3D Geologic Modeling For The Volcanic Reservoir Of Songnan Gasfield

SongNan Gasfield,located in changling fault depression of songliao basin's central downwarped,is a another new break of sinopec's exploration of volcanic rock reservoirs. In the end of 2007, the SongNan Gasfield proven containing gas area declare gas 16.83 km~2, gas geological reserves 537.27 x 10~8m~3 formation volcanic rocks, including gas proven geological reserves 433.66 x 10~8m~3. With the deepening of the exploitation of natural gas field geological structure of geological characteristics and fluid properties, a clearer understanding, need of reservoir characterization quantitatively.Because of the complex lithology,lithofacies, Various types of space, fast lateral variety , large difference between layers ,So, Volcanic reservoir description and prediction is difficult .This paper is based on the advance knowledge of geological study, Using combined well - seismic modeling method, build 3-d tectonic model of SongNan Gasfield.It is think that SongNan Gasfield is a broken nose tectonic on Abraham fault central darfur , Overall performance for west and lower in the east .YS1 wells era tectonic highs in this area, while YS7 and YS4 wells are the second tectonic highs,with And fracture development .In tectonic model framework, based on logging information and geological understanding , taking example by earthquake research results ,using Sequential indicator simulation method , build up a three-dimensional lithofacies model . Mainly consists of stomata breccia, stomata tuff, stomatal flow lines rock, density flow lines rock and dense tuff, The outbreak of phase stomata breccia and stomatal tuff is mainly distributed in the camp 1 paragraph , and the overflow of stomatal flow lines rock is mainly distributed in the camp 2, 3 pieces .In the constraint of the lithofacies model , Analysing reservoir characteristic , Using information constraint modeling method , Combined with gas reservoir ShuiJie understanding of reservoir, carry out the distribution of reservoir fluid properties and 3d modeling . Think stomatal breccia property is best, stomatal flow lines rock next and stomatal tuff poorer, density flow lines rock and dense tuff is every layer . Three volcanic institutions connectivity is poorer, YS1 area containing gas saturation is higher, YP7 and YP4 area appear bottom water .And based on model, adopt volumetric method to evaluate reservoir, and reserve calculation for 206.27 billion total reserves square . Because of gas saturation and area by the influence of the reserves, each block large difference, 3 pieces are subject, the largest block, reserves of total reserves 81.8% reserves; Hang up, camp 1 segment and camp first paragraph 2 is total reserves of gas reservoirs, 92.0%, camp 3 pieces only 3 pieces of gas.Through the analysis of the modeling result of the volcanic rocks of the yingcheng in SongNan Gasfield, thought the plane, YS1 area aangonghe horizons volcano framc petrophysical property good, YP4 area aangonghe horizons times YP7 area aangonghe horizons, is the worst. Hang up, third phase of property is best, the second phase of the second, and the third period, only YS1 Wells worst nearby reservoir development . YS1 areas are the main area , the third and secnod period are main epochs .