美国Appalachian盆地Marcellus页岩气藏开发模式综述

随水平井钻井和分段压裂技术的进步,北美页岩气成功迈入商业化开发阶段,且大型页岩气藏不断涌现,其中以Appalachian盆地的Marcellus页岩气藏最为引人注目。在深入广泛调研国外相关文献的基础上,从地质特征、储层特征、钻井工程、水力压裂、气井生产动态等方面综述了Marcellus页岩气藏的开发模式;并对该气藏的技术进步和开发前景进行了总结。研究结果表明:Marcellus页岩气藏资源量及可采储量巨大,储层物性较好,核心区地层轻微超压、地层主要发育东北和西北走向两组天然裂缝;水平井组是目前主要布井方式,主要采用三段井身结构,水平井段长600~1 800 m;气藏开发初期井距为0.77~1.54口/km2,后期井网加密后井距可达3.09~6.18口/km2;水平井分段压裂段数为4~8段,压裂措施用水量超过18 000 m3,支撑剂用量113~340 t,泵入速度4.77~15.90 m3/min;水平井初期产气量在(4.0~25.0)×104m3/d,单井最终可采储量(0.17~1.13)×108m3。除水平井钻井和分段压裂技术外,其它多项技术也得以发展和进步。Marcellus页岩气藏开发模式综述可为国内页岩气藏的开发提供参考。

The Development Mode Review of Marcellus Shale Gas Reservoir in Appalachian Basin, USA

Shale gas has been commercially developed in North America with the development of horizontal well drilling and multi-stage fracturing technologies. Large shale gas reservoirs are emerging, in which the Appalachian Basin Marcellus shale gas reservoirs is one of the most attractive one. Based on the extensive literature study of international references, the geology, reservoir characteristic, drilling, hydraulic fracturing and well performance of Marcellus shale gas reservoir are reviewed to present the development mode of Marcellus. The technological advances and future development prospects are also provided. The review shows that Marcellus shale gas reservoir owns large gas reserve and recoverable reserve and relatively high-quality reservoir properties. The formation of core area is slightly overpressured and two natural fractures of northeast and northwest are mainly developed. Horizontal well pad is the main well pattern, a typical horizontal wellbore utilizes a three-string casing configuration, and the lateral is 600-1800m. The well spacing in the early stage is 0.77-1.54wells/km₂ and is 3.09-6.18wells/km₂ after the well infilling. Horizontal wells are generally stimulated in 4-8 stages, and a typical slickwater fracturing consists of more than 18000m₃water, 113-340t sand proppant, and the pumping rate of 4.77-15.9 m₃/min. The initial gas production of horizontal well is 4.0-25.0×10₄m₃/d and the corresponding EUR is (0.17-1.10)×10₈m₃. In addition to horizontal drilling and staged fracturing technology, a number of other technologies have gained development and progress. The Marcellus shale gas reservoir development model review in this paper could provide a reference for the domestic shale gas reservoir development.