Description and chemical composition of ferromanganese deposits from Oneida Lake, New York

Saucer-shaped iron-manganese crusts occur adjacent to gravel shoal areas in Oneida lake in central New York. The crusts usually have a crude concentric banding owing to an alternation of orange, iron-rich layers and black, iron-poor layers. Materials from both types of layers are x-ray amorphous. The Oneida lake crusts, like most other freshwater manganese nodules, contain about the same Mn concentration as marine manganese nodules, but are usually higher in Fe and lower in trace metals than their marine equivalents. Although Fe and Mn may be precipitating directly from the lake water, it is more likely that the oxidate crusts are the result of precipitation of Fe and Mn when reduced sediment pore water comes in contact with well oxygenated bottom waters. Organisms, particularly bacteria, may play a role in the formation of the crusts, but to date no evidence of this has been found.

Description of manganese nodules collected by the U.S.S. NERO during survey for a trans-pacific cable

In the early part of 1899 the U.S.S. Nero was dispatched from San Francisco to survey a route for a telegraph cable between the United States, the Philippines Islands and Japan. Concurent with meteorological and oceanographic observations, closely spaced samples of bottom material were systematically sampled. They have been carefully accounted and described by James M. Flint in this volume. On the way, numerous submarine peaks were discovered. During this voyage U.S.S. Nero also took a sounding in the area of the Challenger Deep, recording a depth of 5269 fathoms (9636 m), the greatest depth recorded at that time. Carefull study of the deep-sea deposits have also revealed a number of manganese nodules and encrustations as well as micronodules.

Annotated record of the detailed examination of Mn deposits from DSDP Site 33, Leg 5 (Core 5-33-2)

The proposed location of Site 33 was over north-south Magnetic Anomaly 10 (Pittman-Heirtzler, 32 million years) in order (a) to provide a basis for comparison of the age of the basal sediments with the age based on the magnetic anomaly, (b) to provide a basis for evaluation of relative movement along the Pioneer and Mendocino Fracture Zones, and (c) by being paired with Site 34, to provide comparison of basement materials for adjacent positive and negative magnetic anomalies.