CNPC is making rapid improvements to its horizontal drilling technologies. Breakthroughs have been made in integrating multilateral, extended reach and underbalanced drilling, and geosteering technologies. Significant results have been seen in the application scale and range of horizontal drilling.

Multi-technology integration in horizontal drilling is mainly reflected in four aspects. (1) Underbalanced technologies have been incorporated in horizontal drilling, increasing the production per individual well by more than 4.8 times on average. A nitrogen-injected underbalanced horizontal well witnessed a 90% reservoir encountering rate in China's Southwest Oil & Gas Field, and produced 56,300m3 of natural gas, four or six times as much as each adjacent vertical well prior to reservoir reconstruction. (2) Geosteering technologies support the development of thin reservoirs, bottom-water reservoirs and complex reservoirs, delivering an average encountering rate of 87.4% in 348 well-times in 2008. The CGDS-1 Near-bit Geosteering System with CNPC's independent intellectual property rights has been applied to three horizontal wells in the Liaohe Oilfield with a total drilling footage of 1,047m, showing more accurate near-bit measurement than imported products of the same type. (3) Multilateral horizontal drilling technologies saw multiple application breakthroughs. In Liaohe Oilfield, suspended sidetracking and frictional resistance minimization lateral drilling technology contributed to a record 20-lateral horizontal well with the horizontal interval of 4,333.19m, reaching an initial daily output of 51 tons after acidizing. CNPC also drilled China's first multi-layer lateral well by sidetracking in buried hill formations, with the total in-reservoir interval of 4,369.92m and a daily output of 53.4 tons, six or 10 times as much as individual adjacent well in the same block. (4) Extended reach horizontal drilling technologies were further developed. Seven extended reach horizontal wells with an H/V ratio of more than two have been drilled in Dagang Oilfield by using rotary geosteering and floating casing running. These include well Zhuanghai 8Nm-H3 with an H/V ratio of 3.92, a record for CNPC.

In 2008, CNPC drilled 1,005 horizontal wells, an historic breakthrough to support increasing oil and gas production and reducing development costs.