EGU2020-21098
https://doi.org/10.5194/egusphere-egu2020-21098
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

The transformation effect of source rock-derived acidic fluid on carbonate reservoir from simulation experiments

Qian Ding1,2, Zhiliang He1,2, and Dongya Zhu1,2
Qian Ding et al.
  • 1State Key Laboratory of Shale Oil and Gas Accumulation Mechanism and the Effective Development, Beijing 100083, China; (dingq106@163.com)
  • 2Exploration & Production Research Institute, SINOPEC, Beijing 100083, China;

Deep and ultra-deep carbonate reservoir is an important area of petroleum exploration. However, the prerequisite for predicting high quality deep ultra-deep carbonate reservoirs lays on the mechanism of carbonate dissolution/precipitation. It is optimal to perform hydrocarbon generation-dissolution simulation experiments to clarify if burial dissolution could improve the physical properties of carbonate reservoirs, while quantitatively and qualitatively describe the co-evolution process of source rock and carbonate reservoirs in deep layers. In this study, a series of experiments were conducted with the limestone from the Ordovician Yingshan Formation in the Tarim Basin, and the low maturity source rock from Yunnan Luquan, with a self-designed hydrocarbon generation-dissolution simulation equipment. The controlling factors accounted for the alteration of carbonate reservoirs and dissolution modification process by hydrocarbon cracking fluid under deep burial environments were investigated by petrographic and geochemical analytical methods. In the meantime, the transformation mechanism of surrounding rocks in carbonate reservoirs during hydrocarbon generation process of source rock was explored. The results showed that: in the burial stage, organic acid, CO2 and other acidic fluids associated with thermal evolution of deep source rocks could dissolve carbonate reservoirs, expand pore space, and improve porosity. Dissolution would decrease with the increasing burial depth. Whether the fluid could improve reservoir physical properties largely depends on calcium carbonate saturation, fluid velocity, water/rock ratio, original pore structure etc. This study could further contribute to the prediction of high-quality carbonate reservoirs in deep and ultra-deep layers.

How to cite: Ding, Q., He, Z., and Zhu, D.: The transformation effect of source rock-derived acidic fluid on carbonate reservoir from simulation experiments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21098, https://doi.org/10.5194/egusphere-egu2020-21098, 2020