Study of drilling trajectory control for improving exploration accuracy in Xuefenghu structural belt

Abstract:

With the increase of mineral resources exploration requirements in resent years， the depth of core drilling is rising and the encountered formations are more and more complex. In order to get the ore body in the target area accurately to realize the geological purposes， the requests to control the drilling trajectory is higher. In some working areas of the Xuefenghu structural belt， the dip angle is large with frequent alternation of the soft and hard layers and broken strata. The stratum deflection is serious during the practical construction. As the hole depth increases， the deviation from the ore body in the target area become larger， which affects the exploration accuracy and quality of the mineral resources. In this paper， through deeply analysing the formation deflection， the primary directional technology and the full-hole drilling tool technology are used in the ZK1001 drilling construction， which greatly improves the quality of the borehole and better controlling the drilling trajectory. Moreover， different core drilling tool combinations in different hole sections are tested， some opinions and suggestions for optimizing drilling tool assemblies are put foward， which provides technical reference of drilling trajectory control for coring hole in the working area.

Key words:wire-line core drilling;formation deflection force;trajectory control;primary orientation hole;full hole drill;Xuefenghu structural belt