1 Summary 1.1 Overview of marine mineral resources 1.2 Development history of submarine bedrock deposit mining 2 Engineering geological evaluation and three-dimensional model of the southwest area of Sanshandao Gold Mine 2.1 The geographical location of Sanshandao Gold Mine 2.2 Introduction of ore block in southwest area 2.2.1 Geological situation 2.2.2 Mining conditions 2.2.3 The method of underwater mining 2.2.4 Mining status 2.2.5 Mineral reserves 2.3 Distribution characteristics of overlying strata in southwest wing ore block 2.3.1 Quaternary 2.3.2 Distribution characteristics of quaternary water layer 2.3.3 Distribution characteristics of bedrock weathering zone 2.4 Distribution characteristics of regional faults 2.4.1 Geological characteristics of Xinli main fault (F1) 2.4.2 Structural activity of fault zone in Xinli mining area 2.4.3 Characteristics of ore controlling fault zone (F3) in southwest wing of Xinli mining area 2.4.4 The NW trending fault (F2) 2.4.5 Small-scale fault 2.5 Three dimensional model of ore block in southwest area 2.5.1 Modeling data 2.5.2 Construction of seabed model 2.5.3 Establishment of orebody entity and goal model 2.5.4 Establishment of roadway model 2.5.5 Establishment of fault and fracture zone model 2.5.6 Overall model 2.5.7 Goaf modeling 3 Physical and mechanical properties and constitutive model of fractured rock under the coupling of stress and seepage 3.1 Processing and preparation of rock sample 3.2 Study on porosity of rock sample 3.2.1 Indoor water saturation test 3.2.2 Determination of longitudinal wave velocity 3.2.3 Construction of elastic P-wave and porosity model 3.3 Experimental study on stress seepage coupling of the rock sample 3.3.1 Test equipment and test specimen 3.3.2 Test scheme and test principle ana]ysis 3.3.3 Ana]ysis of stress-strain characteristics 3.3.4 Seepage characteristics ana]ysis 3.3.5 Deformation characteristic an&lysis 3.3.6 Failure characteristics analysis of rock sample 3.4 Construction of stress seepage coupling constitutive model 3.4.1 Effective stress principle 3.4.2 Strain equivalence principle 3.4.3 Construction of the constitutive model 3.4.4 Calculation of parameters in the model 4 The distribution of buried goaf and subsidence area in submarine bedrock mining 4.1 Field survey of goat and subsidence area 4.2 Drilling to survey goaf 4.3 Geological radar detection 4.3.1 Selecting detection instrument and parameter 4.3.2 Determine the dielectric constant of surrounding rock and filling body 4.3.3 Test point arrangement 4.3.4 Processing and analyzing detection data 4.3.5 Analysis of detection results 5 Filling grouting reinforcement technology for seabed broken rock and goaf 5.1 Determination of filling grouting position 5.2 Retaining engineering stability control measures 5.2.1 Retaining roadway support design 5.2.2 Design of shaft cover 5.2.3 Retaining wall design 5.3 Grouting reinforcement technology of Large Dosage Fly Ash-cement mixture 5.3.1 Test materials and equipment 5.3.2 Strength test of fly ash cement test block 5.3.3 Syneresis rate test 5.3.4 Stone rate test 5.3.5 On-site industrial test 5.3.6 Optimization of the proportioning scheme and expected economic benefits 6 Stability evaluation of broken ore and rock based on multi-source information fusion 6.1 Simulation analysis of rock mass stability in the southwest area 6.1.1 Building models 6.1.2 Selection of mechanical parameters of ore and rock 6.1.3 Boundary condition 6.1.4 Simulation scheme 6.1.5 Numerical simulation analysis 6.1.6 Seepage mechanism and stability analysis of aquiclude 6.2