Three Dimensional Geological Modeling And Structural Analysis Of Wolong Temple Anticline In Kangding,Sichuan

Wolong Temple anticline is located in Kangding City,Ganzi Tibetan Autonomous Prefecture,Sichuan Province.The study area is located in the southwest of Xinduqiao Town.The study area is situated at the junction of Yangtze block and Songpan-Ganzi fold belt,looking far into the Ganzi-Litang junction belt,and crossing Xianshuihe active tectonic belt obliquely.It is a strong tectonic-magmatic active area and earthquake-prone area in the region.The strata in the study area are relatively complete and belong to the Yajiang residual basin.Late Triassic flysch sedimentary strata are widely exposed.Magmatic rocks are well developed,mainly Indosinian intermediate-acid intrusive rocks.During the Indosinian-Himalayan period,with the opening of the Ganzi-Litang Ocean and the later composite orogeny,the NW-trending tectonic styles were formed respectively.The study area is located in the eastern margin of the Qinghai-Tibet Plateau.It is influenced by the Ganzi-Litang tectonic belt on the regional scale.Since Neogene,tectonic activities have been frequent.After consulting the previous data and research results,only two-dimensional geological maps and related three-dimensional models are lacking in the study area.Using relevant two-dimensional geological data,such as stratum distribution,structural morphology,to carry out three-dimensional modeling.The main data needed for modeling in the software are seismic,geophysical and geochemical data,and there is a lack of relevant data in the research area.Therefore,in the process of modeling,only the measured section,structural section and field data collected in the study area,such as plane geological sketch,fault occurrence,stratigraphic data,and map cut section of geological sketch can be used.The depth of the model must be limited to ensure the accuracy of the model because of the existence of objective factors.GOCAD software is a relatively mature software.In the study of structure,many operations can be carried out on the model,such as section display in different directions,Z axis of enlarged model,multi-direction rotation,separation demonstration,uncovering demonstration,single geological body display,area and volume calculation,two-dimensional geological map projection and so on.Based on the geological photographs and sketches obtained from field investigation,combined with the three-dimensional model analysis,the fault type can be judged from the dynamic and kinematic indicators of the fault,and the formation age of the fault can be inferred from the regional data,the strata cut and the intrusive body.The Wolongsi anticline is observed and studied through regional overall structural outline,stratigraphic sequence,stratigraphic composition of core and flanks,geometric shape of folds,occurrence and spatial change of axes and junctions,and shape of turning ends.The vertical and deep changes of fold morphology are studied through three-dimensional model,and the small structures inside folds are studied.