Tectonic Types of Oceanic Abyssal Basins and Related Potentially Economic Fields of Ferromanganese Nodules

摘要

Tectonic typification of the abyssal basins of the Atlantic, Indian, and Pacific oceans is proposed. Six types of basins are recognized: perispreading, pericontinental, central thalassogenic. intermontane abyssal, intcrfault, and thalassosyneclise. The tectonic diversity of the basins and their systems reflects significant regional tectono-geodynamic features of the oceanic lithosphere. Basins of the first type are inherent to the Atlantic Ocean; of the second and third types, to the Indian Ocean; and of the fourth to sixth types, to the Pacific. In the Atlantic Ocean, the basins are spatially and paragenetically conjugated with the mid-oceanic ridge. Beyond the Atlantic, a similar situation is characteristic of the southern Indian Ocean only. Hence, differentiated energetic models of deep geospheres are required. The relations of potentially economic fields of ferromanganese nodules to tectonic types of abyssal basins are discussed. The largest fields with respect to both dimensions and reserves are confined to interfault and intermontane abyssal basins. The fields localized in central thalassogenic basins are second in importance. The perispreading and pericontinental basins are the least promising in this respect. Along with other criteria, tectonic analysis should be taken into consideration in the future development of these valuable mineral resources.