Oceanic deposits of the Amur terrane, their age and tectonic implications
In the Amur terrane, oceanic pelagic and hemipelagic chert and siliceous mudstone occur in a small amount and compose thin tectonic slices that are divided by thicker intervals of terrigenous continental margin deposits. Radiolarian biostratigraphic study reveals Middle and Late Jurassic ages of hemipelagic siliceous mudstone and Early Cretaceous ages of continental margin mudstone. This bears on the terranes stratigraphy and demonstrates younging of stratigraphic boundaries between different facies in the south-westerly direction. Multiple tectonic repetitions of oceanic and continental margin deposits are characteristic to accretionary complexes, and such interpretation of the tectonic nature of the Amur terrane matches to the composition and structure of its deposits.