川渝地区含硫气井H_2S释放速率的概率分布模型

Probabilistic distribution model for release rates of H_2S in sour gas wells of Sichuan and Chongqing areas

利用川渝地区含硫气井H2S释放速率数据,根据其累积概率分布函数建立概率分布模型。分别用极大似然法和Kolmogor-ove-Smirnov检验方法估计该模型的标度指数和幂律分布区间的下限,并用Monte-Carlo方法随机生成检验样本,进行拟合优度检验。结果表明,川渝地区含硫气井H2S释放速率的概率分布是非高斯的厚尾分布,一级高危险和二级较高危险含硫气井的累积分布概率远大于高斯分布。若含硫气井H2S释放速率大于0.006 7m3/s,则其服从标度指数为1.539 5的幂律分布,尾部对应一级高危险和二级较高危险含硫气井的概率,主要集中在川东北气矿、川西北气矿、重庆气矿和普光气田等。该模型较合理地描述了川渝地区H2S释放速率的概率分布。

The probabilistic distribution model for the release rates of H2S in the sour gas wells of Sichuan and Chongqing areas was developed using the complementary cumulative distribution function.The model parameters such as the scaling exponent and the lower bound to the power-law behavior were estimated by the maximum likelihood method and the Kolmogorov-Smirnov statistic method.And the latter was also applied to goodness-of-fit tests with the synthetic data generated by the Monte-Carlo procedure from the hypothesized distribution. The release rates of H2S in the sour gas wells of Sichuan and Chongqing areas follow a non-gaussian and heavy tailed distribution. The cumulative probability distribution of level 1 and level 2 sour gas wells is much higher than that of the gaussian distribution. The distribution probability closely follows the power-law behavior with the scaling exponent of 1. 539 5 when the H2 S release rate is over 0. 006 7 m^3 Is, and its tail corresponds to the probabilities of level 1 and level 2 sour gas wells with high hazard. Those sour gas wells mainly located in the northeastern and northwestern areas of Sichuan Gas Field, Chongqing Gas Field and Puguang Gas Field. This model can describe reasonably the probabilistic distribution of the H2S release rates in the sour gas wells of the Sichuan and Chongqing areas.