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As the pioneer of shale gas exploration in China, Longmaxi formation that located in the lower Silurian system in Sichuan basin has entered the developing phase. Under the geological background, seismic and multi-exploration wells' data analysis, it has been proven that the shale gas play in Longmaxi is more complex than it's equivalents in North America. Though the deeper burying depth of Longmaxi has bring extra bonus by higher pore pressure (1.7 to 2.0), Longmaxi is lagging back in some key reservoir quality indicators such as kerogen content and porosity, same time, the compressional tectonic setting and relative active plate movement develop faults and fractures in an unpredictable way brings extra challenge. Driven by the complexity, more and more technologies have been deployed in the development phase to better define the play. Among them, well placement with real-time image, LWD or wireline logging for reservoir quality (RQ) and completion quality (CQ) evaluation and engineering optimized completion design have been recognized as critical steps in better understand shale gas production based on abroad experience. Although it's always appealing to run the integrated methodology with multi-source data for each horizontal well, the tight economic return is preventing field wide implementation.This paper studies multi-well data from an integrated project with PetroChina ZheJiang in Zhao Tong block; examines data acquired from 3 laterals drilled in the same direction in the same pad but utilized different combination of technologies including well placement with real-time image, LWD quad-combo logging with spectroscopy and engineering optimized fracture design. By investigating the micro seismic data and production rate from each lateral, correlation were made to identify the key production drivers and finally lead to the conclusion of the most economic and efficiency technology combination for the horizontal wells development pattern in Sichuan Basin.In conclusion, laterally the heterogeneity of reservoir quality for the same layer in the target platform is not the key production driver. However, reservoir quality and three principal stresses along vertical scope, combining with the nature fracture distribution make a big difference for the completion fracture extension and production rate. As a result, well placement with bedding identification ability being a prevention methodology is quite critical in the mountainous area in Sichuan basin. LWD logging and an

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The performance of shale gas wells varies, and the heterogeneity of shale gas reservoirs requires a good understanding of both reservoir quality (RQ) and completion quality (CQ) of the formation. There are many choices for data acquisition in shale gas horizontal wells, such as wireline conveyance and logging while drilling (LWD). The operator needs to balance between costs, risks, availability of certain measurements and quality of data acquisition. This paper shows a new logging method using a slim tool string that is designed to be conveyed though the drill string and a hollow bit, and the memory data can be obtained when the tool is tripping out. It shows great advantage in lowering the costs, reducing the risks and saving the rig time, when compared to other logging methods. The quad-combo logging suite incorporates spectral gamma ray, density, compensated neutron, array induction resistivity, and array sonic measurements. An integrated formation evaluation derived from the quad-combo data provides answers to RQ and CQ of the shale gas reservoir, which can be the guide for the hydraulic stimulation. Case studies are presented from shale gas reservoirs of Huangjinba Block in Zhejiang Oilfield of PetroChina, which is located at the Zhaotong area of Northern Yunnan and Guizhou provinces. The environmental corrected quad-combo data from the new slim logging tool proves to be consistent when compared with the wireline data in the pilot hole and LWD data in the offset horizontal wells, using a heterogeneous analysis method. A robust and comprehensive petrophysical description of lithology, porosity, permeability, total organic carbon content (TOC), gas content, fluid saturation, and tri-axial stress magnitudes is presented. A new understanding of shale gas reservoir heterogeneity is established. Engineered completion design based on the RQ and CQ has demonstrable value in improving perforation efficiency and production performance. This paper discusses a novel application of a new slim logging tool in formation evaluation of shale gas horizontal wells, and it proves to be efficient and economical. It makes the engineered design for the hydraulic stimulation possible and a success. The workflow can also be applied to other shale gas plays in China.