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Abstract The development of unconventional oil and gas resources fundamentally relies on multi-stage hydraulic fracturing for horizontal wells. Operators also concerned deep reservoirs and those with complex in-situ stress fields. Concurrently, the large-scale fracturing operations significantly increased, leading to increasingly severe issues of casing damage and deformation encountered in the field. Existing instruments such as multi-finger caliper tools and downhole video cameras cannot meet the stringent requirements for wellbore measurement during fracturing. Coiled-tubing (CT) operations or other traditional intervention technology are widely used for deploying Bottom Hole Assembly (BHA), which involves significant investment and operational costs. An alternative wellbore inspection solution to above issues was proposed in this article. This solution integrates both high-frequency wellhead pressure sensors and electromagnetic-based measuring assembly using wireline and hydraulic pumping process. Surface pressure gauges can be quickly connected to the wellhead with maximum sampling frequency of 4000 Hz. Through performing cepstrum and spectral analytics on acquired pressure-wave signals, key characteristic extraction is enabled to assess wellbore integrity. Novel electromagnetic (EM)-based inspection BHA incorporates a magneto-resistive sensors array, effectively probing magnetic-field variations along the casing wellbore. One model for magnetic-field signal processing was provided, which quantitatively characterize wellbore integrity issues such as casing deformation, damage and corrosion. One 45-stage fracturing operation with 288-cluster perforations was conducted in one shale-oil well to validate this solution. Analysis of the water-hammer wave and pressure-drop dynamics after pump shutdown for one certain stage indicated poor fracture propagation as well as damage to the hydrocarbon reservoir. Comprehensive analysis demonstrated a high probability of casing deformation caused by complicated formations. For the another field case, casing deformation and fracture interference always occurred at shale-gas pads. The operator preventively conducted EM-based inspection towards BHA pumping failure and stuck trouble. It was indicated that suspected casing bending occurred in the 4210-4250 m interval and has no negative impact on wireline-used pump operations. Two industrial pilots successfully validated the low-cost and efficient-response solution, which contributes to better wellbore integrity and decision making during operations.