Water production from petroleum (oil and natural gas) wells is a topic of increasing environmental and economic importance, yet quantification efforts have been limited to date, and patterns between and within petroleum plays are largely unscrutinized. Additionally, classification of reservoirs as “unconventional” (also known as “continuous”) carries scientific and regulatory importance, but in some cases the distinction from "conventional" wells is unclear. Using water, oil, and gas production data, we calculated a set of quantitative metrics that elucidate trends in the water-to-petroleum ratio over the life of each producing well. The percent growth of the water-to-petroleum ratio quantifies the degree to which a well “waters out” over time; values calculated for 153,900 wells in 18 oil and gas plays show generally much higher values for conventional wells than for continuous/unconventional wells. Analysis of the percent growth along with the slope and median metrics reveals greater variation between conventional plays and between continuous (unconventional) plays than previously recognized. Further, an example from the Bakken Formation in the Williston Basin, USA, illustrates that, within a single play, the metrics provide insight into spatial variation of water production trends, as influenced by geology and reservoir characteristics. By quantifying the variability of water production trends within individual plays and between plays, including differences between conventional and continuous (unconventional) plays, these results provide a more nuanced view of water production from oil and gas wells than has previously been possible and they illustrate the degree to which water management considerations vary spatially and temporally.

石油（石油和天然气）井的水生产是一个日益重要的环境和经济重要性的话题，但迄今为止量化工作仍然有限，而且石油区之间和内部的模式在很大程度上没有受到审查。此外，将油藏分类为“非常规”（也称为“连续”）具有科学和监管的重要性，但在某些情况下与“常规”井的区别尚不清楚。利用水、石油和天然气的生产数据，我们计算了一组定量指标，阐明了每口生产井生命周期内水油比的趋势。水与石油比率的增长百分比量化了井随时间“水淹”的程度；对 18 个油气区 153,900 口井的计算值显示，常规井的值通常远高于连续井/非常规井的值。对增长率以及斜率和中值指标的分析表明，传统游戏之间和连续（非常规）游戏之间的差异比之前认识到的更大。此外，美国威利斯顿盆地巴肯地层的一个例子表明，在单一区域内，这些指标可以深入了解受地质和储层特征影响的产水趋势的空间变化。通过量化各个区块内和区块之间的产水趋势变化，包括传统和连续（非常规）区块之间的差异，这些结果提供了比以前更细致的油气井产水量视图，并说明了水管理考虑因素在空间和时间上的变化程度。