Natural gas (NG) from shale formations (or shale gas) is an unconventional energy resource whose potential environmental impacts are still not adequately assessed. Hence, this study performs a Life Cycle Assessment (LCA) of shale gas considering a gas well under appraisal in Burgos, Spain.

An attributional model was developed, considering the NG pre-production and production phases in the system boundaries, considering 1 MJ of processed NG as a functional unit. Results were obtained through the CML-IA baseline method (developed by the Center of Environmental Science of Leiden University) and showed that well design, drilling and casing, hydraulic fracturing, NG production, gathering, and processing are critical processes.

To better address the environmental impacts, a comparison with similar studies was carried out, as well as a sensitivity and an uncertainty analysis using Monte Carlo simulation (MCS). The model was found to be particularly sensitive to water usage in hydraulic fracturing and to the number of workovers with hydraulic fracturing.

Limited data availability for shale gas exploration still poses a challenge for an accurate LCA. Even though shale gas remains controversial, it still can be considered as a strategic energy resource, requiring a precautionary approach when considering its exploitation and exploration.

来自页岩地层的天然气（NG）是一种非常规能源，其潜在的环境影响仍未得到充分评估。因此，考虑到西班牙布尔戈斯正在评估的气井，本研究对页岩气进行了生命周期评估（LCA）。

考虑到系统边界中的NG预先生产阶段和生产阶段，并以1 MJ处理过的NG为功能单元，开发了一种归因模型。通过CML-IA基线方法（由莱顿大学环境科学中心开发）获得的结果表明，井的设计，钻井和套管，水力压裂，天然气生产，收集和加工是关键过程。

为了更好地解决环境影响，我们进行了与类似研究的比较，并使用蒙特卡洛模拟（MCS）进行了敏感性和不确定性分析。发现该模型对水力压裂中的用水量和水力压裂的修井次数特别敏感。

页岩气勘探的有限数据可用性仍然对准确的LCA构成了挑战。尽管页岩气仍存在争议，但仍可以视为一种战略能源，在考虑其开发和勘探时需要采取预防措施。