Macrofabric fingerprints of Late Devonian-Early Carboniferous subduction in the polish variscides, the Kaczawa complex, Sudetes

We describe a remarkably preserved assemblage of sedimentary and tectonic f abrics in cores from the Kaczawa complex, Sudetes, SW Poland. These fabrics indicate a continuum of process from repeated remobilization of Upper Devo nian-Lower Carboniferous muddy flysch and volcaniclastic sediments as debri s flows and olistostromes, to fracturing, fluid-streaming and soft-sediment injection triggered by high pore-water pressures during the initial stages of tectonic deformation: to contractional cleavage formation and local cat aclasis while the sediment was still only partially consolidated. These str uctures are similar to those described from ODP cores through the toes of a ctive accretionary prisms. They indicate active subduction of oceanic crust during the Late Devonian, suggesting that ophiolite obduction and signific ant overthrusting in the Sudetes occurred as an integral part of the Varisc an orogeny.