This　study　focuses　on　determination　of　the　effective　hydro-mechanical　properties　of　a　widespread　geological　me　＇　lange,　the　Soil-Rock　Mixture　(SRM),　using　the　multiscale　Numerical　Manifold　Method　(NMM).　Influences　of　the　Volumetric　Block　Proportion　(VBP),　block　size,　block　shape,　block　orientation　angle　and　micro-dynamics　on　the　effective　properties　are　investigated　thoroughly.　The　SRM　structural　models　are　generated　within　the　NMM　framework　in　a　statistical　manner.　The　effective　properties　are　extracted　using　the　multiscale　theory　where　micro-dynamics　is　fully　considered　based　on　the　extended　Hill-Mandel　lemma.　Through　numerical　simulations,　the　VBP　and　block　orientation　angle　prove　to　be　the　first　and　second　most　influential　factors.　A　growing　VBP　leads　to　increasing　deformation　moduli　but　decreasing　effective　permeability　and　Biot＇s　factor.　Normal　com-ponents　of　permeability　and　deformation　tensors　are　positively　proportional　to　the　corresponding　normal　intersecting　areas　formed　by　sample　cross-sections　and　blocks　while　shear　components　are　positively　propor-tional　to　sums　of　the　normal　and　shear　intersecting　areas.　Introducing　micro-dynamics　and　diminishing　the　time　step　make　the　effective　permeability　and　deformation　moduli　rise　while　Biot＇s　coefficient　decrease.　The　accuracy　and　stability　of　the　multiscale　NMM　are　validated　by　comparing　present　results　with　those　of　empirical　formulae　and　single-scale　numerical　methods.