Observation of manganese nodules and manganese coated coral in the West Northern Atlantic ocean

Photography has become an integral part of submarine geological and biological investigations of the ocean bottom. The underwater cameras used to make these photographs were designed by Harold Edgerton. The pictures were taken from 1960 to 1962, from ships of the Woods Hole Oceanographic Institution. They show that life occurs even in the deepest trenches, and that sedimentary and biological processes in deep water do not differ in kind from those in shallow water.

Observation of manganese nodules on the Muir Seamount during Atlantis Cruise 260

Seamounts are very effectively studied by deep-sea photography. Each photograph can be considered as a sample point when used in connection with bathymetric surveys, dredge samples, and cores, thus making it possible to delineate and map geologic and biologic zones on a seamount. Seamounts transcend through a great depth range and are characterized by minimal sedimentation which results in exciting and photogenic differences of environment over a short distance, as typified by our studies of Great Meteor and the New England Seamounts.

Geochemistry and descriptions of manganese nodules and crusts retrieved from the open ocean

The book is a compilation of all available data at the time of publication (1965) on the subject of marine minerals together with the author's original ideas regarding their exploitation. It is one of the most significant publications on ocean resources. It is particularly focused on manganese deposits, their description, sedimentary setting, formation and geochemistry.

Observation of manganese coating and encrustation in different environments of the North-Western Atlantic ocean

The major topographic features, or provinces, beyond the continental slope off the Atlantic coast of the United States are (1) Sohm Plain, (2) Hatteras Plain, (3) Nares Plain, (4) Blake Basin, (5) Blake Plateau-Bahama Banks, and (6) Bermuda Rise. The whole of the described area is commonly referred to as the North American Basin. This basin is bounded on the north by Newfoundland Ridge and on the south by Puerto Rico Trench. Topographic features of note within the basin are the divide and the area of depressions between Sohm and Hatteras Plains, the sharply crested Blake Ridge, and the Puerto Rico Ridge. Recently accumulated data on deep-sea oores has given good evidence that the silt and sand covering the abyssal plains are displaced continental sediments in a virtually quartz-free oceanic environment. These sediments were deposited on a primary volcanic bottom. The primary or volcanic bottom is characterized by abyssal hills and seamounts, and the sediment bottom is characterized by abyssal plains, which extend seaward from the continental margins. On the Blake Plateau, bottom photographs and dredge hauls in the axis of the stream show that locally sediment has been removed and the bottom is paved with crusts and nodules of manganese. Photographs and dredged samples from the outer part of the New England Seamount, Chain and Caryn Peak also indicate extensive encrustations of manganese oxide which acts as a binding agent in areas of ooze or other organic debris and thus helps to stabilize the bottom.

Observation of manganese nodules and encrustations in various lakes of Finland

The limnic ferromanganese ore concretions in some Finnish lakes are described. Their chemical and mineral compositions have been measured as have their natural surroundings - the latter by means of physico-chemical in-situ analysis. The sources of the nodules' contents are discussed, and a theory based on the calculated precipitation fields of the important ore minerals is presented for the ore formation.

(Table 1, Page 1046-1047) Chemical composition of iron-manganese concretions from the Indian Ocean recovered by the R/V Vityaz and the R/V Ob

The data given in this and previous communications is insufficient to assess the quantitative role of these supplementary sources in the Indian Ocean, but they do not rule out their local significance. Elucidation of this problem requires further data on the characteristics of the composition and structure of nodules in various different metallogenic regions of the ocean floor. A study of the distribution of ore elements in nodules both depthwise and over the area of the floor together with compilation of the first schematic maps based on the results of analyses of samples from 54 stations) enables us to give a more precise empirical relation between the Mn, Fe, Ni, Cu, and Co contents in Indian Ocean nodules, the manganese ratio and the values of the oxidation potential, which vary regularly with depth. This in turn also enables us to confirm that formation of nodules completes the prolonged process of deposition of ore components from ocean waters, and the complex physico-chemical transformations of sediments in the bottom layer. Microprobe investigation of ore rinds revealed the nonuniform distribution of a num¬ber of elements within them, owing to the capacity of particles of hydrated oxides of manganese and iron to adsorb various elements. High concentration of individual elements is correlated with local sectors of the ore rinds, in which the presence of todorokite, in particular, has been noted. The appearance of this mineral apparently requires elevated Ca, Mg, Na, and K concentrations, because the stable crystalline phase of this specific mineral form of the psilomelane group may be formed when these cations are incorporated into a lattice of the delta-MnO2 type.

(Table 2, Page 252) Average chemical composition of 11 manganese nodules and crust from the Pacific Ocean

The ability of the hydrated oxides of manganese and iron to adsorb ions from solution (scavenging) is considered in relation to some problems in marine geology, chemistry, and biology. In the ferruginous sediments of the Pacific Ocean, iron oxides are accompanied by titanium, cobalt, and zirconium in amounts proportional to the iron content. Similarly, copper and nickel are linearly related to the manganese content. These observations are explained on the basis of scavenging. An electrochemical theory for the formation of manganese nodules is presented. Marine sediments are classified on the basis of the geosphere in which the solid phases originate. The distribution of certain ionic species in sea water between the solid and aqueous phases is considered on the basis of scavenging and co-ordination compound theory. The concentration of minor elements by members of the marine biosphere is explained either by the direct uptake of the element or by the uptake of iron or manganese oxides with the accompanying scavenged element.

(Table 5, page 206) The uranium contents of some manganese nodules

The uranium concentrations in marine calcareous material of a biological origin varied between 0.0X and 0.X p.p.m. with the exception of corals which had concentrations of several p.p.m. The aragonitic oolites and aragonite precipitated from sea-water had values similar to those of the corals. A geochronology based on the growth of ionium (thorium-230) from uranium is applicable not only to corals, as previous investigators have pointed out, but also to oolites. Several examples of "oolite ages" are given. The uranium content of ferromanganese minerals from pelagic deposits is of the order of from 4 to 5 p.p.m.

(Table 1, page 754) Estimated concentrations of various elements in nineteen manganese nodules

Using spectrochemical techniques Fe, Si, Mg, Co, Ni, Cu, V, Mo, Ti and Tl have been estimated in nineteen manganese nodules, eight from the Atlantic ocean, seven from the Pacific ocean and four from the Indian ocean. Though data on more samples are required before firm and detailed conclusions can be made about the distribution of elements in manganese nodules, several distinct features appear when the data on the nineteen samples are examined. Certain elements appear to enrich more strongly than others. For example, relative to igneous rocks Mo is much more strongly enriched than V. For several elements (Ni, Cu and particularly Co and Tl) the degree of enrichment in two Fe-low nodules is far smaller than in the other nodules. The magnitude of dispersion of concentration appears to vary considerably for different elements; thus, whereas variation of concentration of V is relatively small, that of Ni, Cu, Co and Tl is far larger. The statistical nature of the distribution of Fe in manganese nodules appears to be characteristic and different from that of the other elements studied so far. Of the possible inter-element relationships examined that of Ni-Cu appears to be the most strongly developed.

(Table, page 351-359) Chemical composition of manganese nodules and crusts from the Pacific and Indian Ocean

Chemical and mineralogical analyses of manganese nodules from a large number of widely spaced localities in the Pacific and Indian Oceans have shown that their mineralogy and chemical composition varies both areally and with depth of formation. This is considered to result from a number of factors, important among which are: (a) their proximity to continental or volcanic sources of elements; (b) the chemical environment of deposition, including the degree of oxygenation; and (c) local factors such as the upward migration of reduced manganese in sediments from certain areas. Sub-surface nodules appear to share the chemical characteristics of their surface counterparts, especially those from volcanic areas where sub-surface sources of elements are probably important.