Genesis of lacustrine carbonate breccia and its significance for hydrocarbon exploration in Yingxi region, Qaidam Basin, NW China

Yanqing WANG,Zhanguo LIU,Guangyong SONG,Yongshu ZHANG,Chao ZHU,Senming LI,Peng WANG,Pengcheng TANG

Fig. 3. Photographs of diagenetic breccia in upper member of Lower Ganchaigou Formation in Yingxi area. (a) Well S41-2, 4203.96-4 204.36 m, diagenetic breccia, euhedral anhydrite- glauberite mineral growth in penecontemporaneous period propping open and causing deformation of weak consolidated argillaceous limestone, and the argillaceous lime-dolomite appears breccia-like shape after being washed and dissolved by mud during drilling; (b) Well S41-2, 4 120.93-4 121.19 m, diagenetic breccia, with the same characteristics as (a) ; (c) Well S41-2, 4 204.3- 4203.8 m, diagenetic breccia, needle-strip self- shaped anhydrite mineral growth cutting argillaceous lime-dolomite into breccia-like shape; (d) Well S41-6-1, 3 864.58-3 864.68 m, diagenetic breccia, needle- and plaque-like euhedral anhydrite mineral growth cutting argillaceous lime-dolomite into breccia-like shape; (e) Well S41-6-1, 3 861.48-3 861.61 m, diagenetic breccia, with the same characteristics as (d) .