ND ISOTOPES LINK OUACHITA TURBIDITES TO APPALACHIAN SOURCES

New Nd isotopic data suggest that Paleozoic turbidities in the Ouachit a fold belt (Arkansas and Oklahoma) had a dominantly Appalachian prove nance after Middle Ordovician time. We infer a long-lived sedimentary dispersal system of isotopically homogeneous detritus linked to Appala chian tectonics. By Carboniferous time, both the continental surface a nd the closing Ouachita trough were apparently flooded with sediment d erived from the Appalachian collisional orogen.