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Abstract Lithofacies and fracture characterization are challenging in mixed lithological reservoirs, especially for volcanic-carbonate-igneous combination in the B deepwater area of South China Sea. Natural fractures development is highly controlled by lithofacies and/or lithofacies combination, and fault activities. Understanding fracture development in multi perspectives and characterizing reservoir quality are critical to identifying hydrocarbon reservoirs and optimizing testing theme. Triple combo logging, masterlog, core data and electrical and ultrasonic borehole imaging logs, and cross dipole shear waves, and Stoneley waves were utilized to characterize lithofacies, fractures and dissolution pores. A total of thirteen lithofacies within four categories were identified, namely (1) volcanic lithofacies: tuff/volcanic breccia; (2) igneous lithofacies: granite porphyry and basalt/altered basalt; (3) limestone lithofacies: sandy/shaly/bioclastic limestone; (4) dolomitic lithofacies: altered/dolomite. Both electrical image and ultrasonic image were used to identify fractures and calculate fracture parameters. Based on the amplitude image and travel time image, five types of fractures are identified: closed fractures filled with clay, closed fractures cemented by calcite/quartz, fully open fractures, partially open fractures, and vuggy open fractures. Partially fractures were the most developed, accounting for 61%, followed by vuggy open fractures, accounting for 29%, and closed fractures accounting for 10%. To identify favorable hydrocarbon zones, the mud gas, electrical and ultrasonic borehole imaging logs, cross dipole shear wave (DTXX and DTYY) and petrophysical interpretation were integrated, and two gas zones were discovered. The gas Zone 1 shows bioclastic limestone at the top, altered massive basalt and dolomite in the middle and laminated altered basalt interbedded with limestone at the bottom. 48 effective fractures are developed, with more than 25% vuggy open fractures, and fracture aperture ranges from 140 to 690um, and maximum fracture porosity is 0.2%. The gas Zone 4 is mainly altered basalt with only 5 effective fractures, and fracture aperture ranges from 280 to 390um, and maximum fracture porosity is 0.055%. Time delay and frequency shift from dipole shear wave data are relatively higher within the two gas zones, and the absolute difference between DTXX and DTYY is between 10 to 28 in the two gas zones, which further confirmed the fracture development. Subsequently, supervised geological facies classification was conducted, and five geological facies were identified with the reservoir quality in the order: Facies A > Facies B > Facies C > Facies D > Facies E. The final testing zones were selected within the Zone 1, which owns higher percent of Facies A and Facies B versus Zone 4. The lithofacies identification workflow is efficient in the mixed volcanic-carbonate-igneous reservoirs, and the fracture characterization method by multi perspectives aided accurate hydrocarbon identification together with petrophysical analysis. This workflow and methodology are applicable in other appraisal wells and can provide reliable inputs for reservoir production prediction.