The Study Of Sequence Stratigraphy And Reservoir Of Jialingjiang Formation Of Triassic In Luzhou Paleohigh

In recent years, the discovery of three equipped gas fields---Maliuchang, Tongliuchang and Yinbin gas field lay out the wide exploration foreground of Jialingjiang Formation in South of Sichuan. So it is important for coaching production to evaluate reservoir and open out development disciplinarian of reservoir of Jialingjiang Formation in Luzhou paleohigh.In this paper through core and well logging data, on the base of establishment of framework of high frequency sequence stratigraphy of carbonate rocks in work area, the development and distribution of shoal in framework of high frequency sequence stratigraphy is satisfying studied by analysis of geological background, analysis of sedimentary facies, and fine explanation of well logging; The character and shaping of reservoir is seeked after by studing of lithology and geochemical research; Further, the efficient predicting of development and distribution of carbonate reservoir of Jialingjiang Formation in work area is achieved by analysis of controlling of development of carbonate reservoir by sequence stratigraphy, sedimentation and diagenesis. The main production is given as follows:1)The distribution character of each segment stratigraphy is: the change of thickness from Tj₁²-Tj¹ to Tj₂³, from Tj₁⁴-Tj₃³ to Tj₄⁴, from Tj₁⁵ to Tj₂⁵ is consecutive and erosion character of Jialingjiang Formation in Luzhou paleohigh is: the distribution of denudation area from Tj₁⁵ to Tj₂⁵, from Tj₄⁴ to Tj₂⁴ is consecutive and the Tj₁⁴-Tj₃³ area is solitary.2)According to the result of study of adjacent area and the fact of work area, it is considered that in work area lower-middle Triassic that includes Jialingjiang Formation is made up of 1 two-order sequence. Furthermore, Jialingjiang Formation is divided into 2 three-order sequence.3)According to study, it is considered that rock type and cycle variety of log curve is the key to dividing Jialingjiang Formation in work area into high frequency sequence. Then, 18 characters of high frequency sequence of upwards shoaling and their cycle variety of log curve is identified and for the first time, high sequence stratigraphy framework of Jialingjiang Formation in Luzhou ancient hunch is set up.4)Combined with predecessor's data, according to identify symbol of sedimentary facies, sedimentary facies type are confirmed in work area. Then, the distribution of sedimentary facies is studied in system tract and high frequency sequence, and the cognition is: the evolvement of sedimentary facies is corresponding with sea level change, TST and HST has different depositional model.5)The relationship of high frequency sequence and reservoir is well studied and through setting up reservoir comparison diagram in high frequency sequence framework, the reservoir distribution and development is controlled by three-order sequence and high frequency sequence, most is seen in HST, fewer in TST and the formation is controlled by the five-order sequence evolvement, under the background of arid climate and humid climate, the formation has different model. And then, the development position of reservoir in five-order sequence is various.6)It is point out that the main mechanism of forming reservoir is chemical erosion of atmospheric water in penecontemporaneous; Karstification because of denudation of Luzhou ancient hunch of Indosinian is important for froming reservoir.7) According to study of the relationship of reservoir and sequence stratigraphy, sedimentary facies, the predicting and evaluating of beach reservoir, dolomite reservoir and carst reservoir is studied in effect in high frequency sequence and si 41-si2 area and yun 11-tanl 3 is the exploration target.