Geology, mineralogy, and chemistry of sediment-hosted clastic massive sulfides in shallow cores, Middle Valley, northern Juan de Fuca Ridge

faults basalts D/H East Pacific alkaline earth metals metasomatism mid-ocean ridge basalts Pacific Ocean isotope ratios Juan de Fuca Ridge metals paragenesis sea water isotopes oxygen hydrogen lead mineral deposits, genesis Middle Valley North Pacific radioactive isotopes S-34/S-32 sedimentation strontium sulfur stable isotopes Pb-207/Pb-204 Northeast Pacific Pb-206/Pb-204 sediments volcanic rocks Sr-87/Sr-86 igneous rocks O-18/O-16 Pb-208/Pb-204 tectonics