??據全球能源新聞網8月7日報道，根據雷斯塔能源（Rystad）分析顯示，美國致密油運營商數月來一直在耗盡其已鉆井但尚未完工的油井（DUC）庫存，隨著鉆井反應的放緩，2021年6月，該國主要油區“活躍的”DUC數量驟降至2381口，為2013年以來的最低水平。

　　截止6月底，二疊紀、鷹福特（ Eagle Ford）、巴肯（Bakken）、尼奧布拉拉（Niobrara）和阿納達科（Anadarko）地區的水平DUC總數下降到4,510口井。這意味著從2020年6月6340口井的峰值減少1800口，在過去12個月內每月平均消耗150口井。上一次庫存規模達到這一水平是在2018年下半年。

　　然而，總數包括所謂的“廢棄的”DUC，即24個多月前鉆探且尚未完工的油井。根據經驗證據表明，95%以上的鉆井通常在頭兩年內完成，因此那些兩年以上的井現在完成的概率很低。因此，包括“廢棄的”DUC來衡量未來活動或預測產量往往更具投機性。

　　雷斯塔能源公司頁巖研究負責人Artem Abramov表示，從剩余的“活躍”DUC數量來看，在2022年上半年之前，美國陸上工業對每桶 70-75 美元的WTI市場做出大量的石油供應反應幾乎是不可能的。任何進一步的壓裂增加，以及隨后的油井完井，現在將要求生產商首先通過增加更多鉆機來擴大鉆探規模。

　　除阿納達科地區外，所有主要含油盆地的活DUC均有所下降。截至6月底，二疊紀僅有約1550口水平活躍DUC，較去年同期的2470口下降了37%。由于自新冠疫情引發的衰退開始以來，二疊紀的鉆機活動保持了更強勁的勢頭，但與所有其他盆地的情況一樣，活躍的DUC庫存總量并未恢復到2013年的水平。

　　目前二疊紀盆地活躍DUC庫存水平與2019年第二和第三季度相當。其他主要含油盆地的情況則更令人吃驚。南德克薩斯的鷹福特和巴肯各只剩下300口活躍DUC。自2010年以來，這兩項開創性的油氣勘探從未達到如此高的水平。尼奧布拉拉地區的活躍DUC庫存已降至310口，為2013年以來的最低水平。

　　根據按鉆探年份或油井被鉆探的年份劃分的致密油DUC庫存總量的細目，清楚地表明，截至今年6月， 2019 - 2020年的年份對壓裂活動具有重要影響。雖然新的油井正在鉆探，但2021年的新庫存不足以抵消2021年之前年份的枯竭率。

　　在之前的幾個月里，我們反復強調2019年第四季度和2020年前三個月這一時期是新冠疫情引起的低迷開始時異常高的DUC庫存積累的關鍵因素。截止今年6月，這些井的84%已經完工。雖然仍略低于2016年第四季度-2017年第一季度和2017年第四季度-2018年第一季度14個月創紀錄的枯竭率(92-93%)，但與2018年第四季度-2019年第一季度和2019年4月至2020年6月期間的87%相當。

　　盡管仍存在一定程度的異常，但該行業距離 DUC庫存水平完全正常化并不遙遠。截至2021年6月，在二疊紀地區，每臺鉆機的水平活躍DUC數量已降至6.4口，其他主要油區為9.2口。在新冠疫情衰退之前，二疊紀的水平為3.9口，其他油區為6.4口。考慮到目前的活動和枯竭趨勢，該行業可能會在9月底看到二疊紀盆地的完全正常化，并在9月至10月期間看到其他油區的完全正常化。

　　郝芬 譯自 全球能源新聞網

　　原文如下:

　　US DRILLED UNCOMPLETED WELL INVENTORY TO LOWEST LEVEL SINCE 2013

　　US tight oil operators have for several months been depleting their inventory of drilled but uncompleted wells (DUCs) and, amid a slower drilling response, the number of ‘live’ DUCs in the country’s major oil regions slumped to 2,381 wells in June 2021, the lowest level since 2013, a Rystad Energy analysis reveals.

　　The total number of horizontal DUCs in the Permian, Eagle Ford, Bakken, Niobrara and Anadarko regions combined fell to 4,510 wells by the end of June. That implies a reduction of 1,800 wells from the peak of 6,340 in June 2020 and an average depletion of 150 wells per month over the past 12 months. The last time the size of the inventory was at this level was in the second half of 2018.

　　However, the total includes so-called ‘dead’ DUCs – or wells that were drilled more than 24 months earlier and remain uncompleted. Empirical evidence shows that more than 95% of wells drilled are typically completed within the first two years, and hence the probability of those more than two years old getting completed now are low. Therefore, including ‘dead’ DUCs to gauge future activity or forecast production is often more speculative.

　　“Looking at the number of remaining ‘live’ DUCs, a significant oil supply response from the US onshore industry to the $70-$75 per barrel WTI market is practically impossible before the first half of 2022. Any further increases in fracking, and subsequently well completions, will now require producers to first expand drilling by adding more rigs,” says Artem Abramov, head of shale research at Rystad Energy.

　　Live DUCs have declined across all major oil basins, with the Anadarko region the only exception. In the Permian, only about 1,550 horizontal live DUCs remain as of end of June – a decline of 37% from the 2,470 wells in the same month last year. As rig activity in the Permian has remained more robust since the start of the Covid-19-induced downturn, the total live DUC inventory count has not returned to the 2013 level, as is the case for all other basins combined.

　　The Permian live DUC inventory level currently is comparable to the second and third quarters of 2019. The picture across other major oil basins is more dramatic. South Texas’ Eagle Ford and the Bakken only have 300 live DUCs each left. Such a level in these two pioneering liquids plays has not been recorded since 2010. The inventory of live DUCs is down to 310 in the Niobrara region – the lowest since 2013.

　　A breakdown of the total tight oil DUC inventory by spud vintage, or the year the wells were spud, clearly shows that 2019-2020 vintages had a significant weightage on fracking activity as of June. While new wells are being drilled, the new inventory build-up in 2021 is insufficient to offset the depletion coming from pre-2021 vintages.

　　In previous months, we repeatedly highlighted vintages from the fourth quarter of 2019 and the first three months of 2020 as key contributors of the unusually high DUC inventory build-up in the beginning of the Covid-19-induced downturn. By June 2021, 84% of those wells were completed. While it is still somewhat lower the 14-month depletion rate of 92-93% recorded for 4Q16-1Q17 and 4Q17-1Q18 vintages, it is comparable to the 87% posted for the 4Q18-1Q19 vintage between April 2019 and June 2020. Hence, this part of the DUC inventory anomaly has been largely eliminated by now.

　　While some degree of abnormality is still present, the industry is not that far off from a complete normalization of the DUC inventory level. The number of horizontal live DUCs per rig has already declined to 6.4 wells in the Permian and 9.2 in other major oil regions as of June 2021. Prior to the Covid-19 downturn, the level was at 3.9 for the Permian and 6.4 across other oil regions. Given the current activity and depletion trend, the industry will likely see a complete normalization by the end of September in the Permian, and by September-October across other oil regions.