Wire-line core drilling for Songnan oil shale survey in the Songliao Basin

Abstract:

The Songnan oil shale formation in the Songliao Basin is highly water-sensitive, which is prone to be hydrated, spalled, and even collapsed during drilling. With use of the S95+5 wireline coring process, and optimization of the borehole structure, bit type, drilling fluid and drilling parameters, the difficulty of protection of borehole walls in oil shale formation was successfully solved, achieving engineering quality requirements. This paper summarizes the key technologies in wireline coring in oil shale formation so as to provide technical reference and guidance for the similar drilling works.