Research of Drilling Complexities in Dabei Belt of Tarim Basin

Abstract

Kuche depression of Tarim Basin went through tectogenesis many times, due to the southward thrust compressional stress from Tianshan fold uplift, the geology condition of this area is extraordinarily complex, there are problems such as depth difference in geological horizons, abnormal pressure formations and irregular distribution of special lithologies, etc. All of these problems have brought even more difficulties in engineering design and construction. Accidents such as well leakage, drilling sticking and complex situations happened frequently. All of those have influenced the engineering progress seriously and lowered the actual effect of drilling. In order to resolve the problems and complex situations above, we did detailed researches on accidents in the Kuche piedmont belt of Tarim Basin and studied reasons for complex situations, and then we proposed engineering resolutions and evaluated them.

Geology-engineering integration to improve drilling speed and safety in ultra-deep clastic reservoirs of the Qiulitage structural belt

“…To date, the number of wells in this block has reached 36, with an average well depth of 7,026 m and the deepest well exceeding 8,200 m. The average drilling cycle is 326 days, and the proportion of complex accidents and aging accounts for 18%. Long drilling cycle, high accident complexity rate and low natural productivity of a single well are the key limiting factors of the effective development of ultra-deep natural gas in the Qiulitage structural belt (Hou et al, 2011).…”