Fossil Mn nodules of Cretaceous age from western Timor exhibit chemical, structural and radioisotope compositions consistent with their being of deep-sea origin. These nodules...
Sediment, saprolite, and water samples from the Rio Guayanés and Rio Guayabo rivers in Yabucoa, Puerto Rico. Sediment and saprolite is underlain by granodiorite and is of the Late Cretaceous. The foll
