碳酸盐岩盖层突破压力的影响因素分析

Influencing factors for breakthrough pressure of carbonate caprocks

张璐 国建英 林潼 谢增业 杨春龙 董才源 郭泽清 郝爱胜

ZHANG Lu GUO Jianying LIN Tong XIE Zengye YANG Chunlong DONG Caiyuan GUO Zeqing HAO Aisheng

中国石油勘探开发研究院, 北京 100083 中国石油天然气集团有限公司 天然气成藏与开发重点实验室, 河北 廊坊 065007

PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China CNPC Key Laboratory of Gas Reservoir Formation and Development, Langfang, Hebei 065007, China

除传统的膏盐岩和泥页岩外，较多研究证实碳酸盐岩也可作为油气封盖层。突破压力是盖层封闭能力评价的特征参数，通过对塔里木盆地不同岩性类型、不同样品长度的碳酸盐岩在不同温度下进行突破压力测定实验，分析岩石特征、温度、样品长度对实验结果的影响。岩性、渗透率及裂缝发育情况对结果影响明显；相同温度下，样品长度跟突破压力结果没有较好的相关性；不同温度下，大部分样品随温度的升高突破压力逐渐降低。因此在盖层评价中地温对盖层的封闭能力有着不可忽视的作用，是盖层封闭能力评价需要考虑的关键因素，高地温情况下泥质含量高的碳酸盐岩具有更好的封闭能力。

In addition to traditional gypsum salt rocks and shale rocks, many studies have confirmed that carbonate rocks also work as oil and gas seals. Breakthrough pressure is a characteristic parameter for the evaluation of the sealing ability of cap rocks. Different lithology types and lengths of carbonate rocks were subjected to breakthrough pressure measurement experiments at different temperatures, results showed that lithology, permeability and fracture development have obvious effects to rock characteristics. At the same temperature, sample length does not have a good correlation with breakthrough pressure, however, at different temperatures, the breakthrough pressure of most samples gradually decreases with the increase of temperature. Therefore, formation temperature has a non-negligible effect on the sealing ability of cap rocks. It is a key factor that needs to be considered for the evaluation of the sealing capacity of cap rocks. The carbonate rock with a high argillaceous content has better sealing capacity under high geothermal conditions.

国家科技重大专项 2016ZX05007-003;中国石油股份公司科技项目 2019B-0605

https://doi.org/10.11781/sysydz202103461