Department of Energy Resources Engineering , Stanford University , Stanford , California 94305 , United States.
Scientific Aviation , Boulder , Colorado 80301 , United States.
Environ Sci Technol. 2018 Aug 7;52(15):8947-8953. doi: 10.1021/acs.est.8b01665. Epub 2018 Jul 26.
We performed an infrared optical gas imaging (OGI) survey by helicopter of hydrocarbon emissions in the Bakken formation of North Dakota. One year after an earlier survey of 682 well pads in September of 2014, the same helicopter crew resurveyed 353 well pads in 2015 to examine the persistence of emissions. Twenty-one newly producing well pads were added in the same sampling blocks. An instrumented aircraft was also used to quantify emissions from 33 plumes identified by aerial OGI. Well pads emitting methane and ethane in 2014 were far more likely to be emitting in 2015 than would be expected by chance; Monte Carlo simulations suggest >5σ deviation ( p < 0.0001) from random assignment of detectable emissions between survey years. Scaled up using basin-wide leakage estimates, the emissions quantified by aircraft are sufficient to explain previously observed basin-wide emissions of methane and ethane.
我们乘坐直升机对北达科他州 Bakken 地层中的碳氢化合物排放进行了一次红外光学气体成像（OGI）调查。在 2014 年 9 月对 682 个油井平台进行了早期调查一年后，同一架直升机机组于 2015 年再次对 353 个油井平台进行了调查，以检查排放物的持续存在情况。在相同的采样区块中增加了 21 个新投产的油井平台。一架装有仪器的飞机也被用来量化空中 OGI 识别的 33 个羽流的排放物。在 2014 年排放甲烷和乙烷的油井平台在 2015 年排放的可能性远远高于随机预期；蒙特卡罗模拟表明，与探测到的排放物在调查年份之间的随机分配相比，存在超过 5σ的偏差（p<0.0001）。利用盆地范围内的泄漏估算值进行放大，飞机定量的排放量足以解释先前观察到的盆地范围内甲烷和乙烷的排放量。
