The Niobrara formation is an increasingly active exploration target in the Denver-Julesburg basin that contains both reservoir rock and source rock. The reservoir rock consists of up to four laterally continuous chalk benches and the source rock is comprised of three organic-rich interbedded shales. Both permeability and porosity in the Niobrara chalk are relatively low and production is expected to be enhanced by natural fractures related to: horst and graben structures, dissolution of evaporite beds, wrench faulting, listric faulting, regional stresses, and pore pressure. To develop the Niobrara formation, horizontal drilling combined with multistage hydraulic fracturing increasingly is used. To enhance reservoir understanding and optimize field recovery, advanced logging-while-drilling (LWD) services are now available for real-time acquisition and transmission of high-resolution electrical images of the borehole, azimuthal gamma ray, and multi depth measurement of formation resistivity. Analysis of this information in real time with high data rate LWD acquisition telemetry allows proactive well-placement decision making by comparing apparent dip of the formation to the borehole trajectory. This is effectively used for maximum reservoir contact of the lateral wellbore in the desired chalk bench. In addition, the analysis of the high-resolution images facilitates fracture identification, fault estimation, and structural analysis for the optimization of stage designs for hydraulic fracturing. This paper will expand the use of LWD with high-resolution image interpretation, formation evaluation, fracture system analysis, and structural analysis for the purpose of drilling better-performing wells through optimized well placement and hydraulic fracturing operations.

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