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The article reports on the seabed mineral resources that are present in many parts of world's ocean. It discusses the different types of minerals to be found in the continental margins from those of the deep seabed. Minerals in the continental margins generally contains the same kind of mineral deposits while in the deep seabed a small variety of minerals, like the manganese nodules. An overview of the possible economic potential of deposits of the deep seabed, manganese nodules in particular, is offered.

Methods whereby an Asdic may be used empirically to examine the sea bed are discussed. They indicate that on flat sea bottoms the effects of impedance and attenuation combine to produce a record usually distinctive enough to broadly classify the sediment over which the vessel is passing. These methods were used to interpret an area of unconsolidated sand, gravel and mud in the region of Arklow off the east Irish Coast. Echo-sounder traverses and sea bed sampling were also employed to assist with the interpretations. The sea bed is composed of dissected residual gravels covered in places with mobile sand displaying a great variety of high-energy bed forms. Mechanisms of sub-littoral sediment circulation, based largely on the bed forms recognized in the Asdic records, are also discussed. [ABSTRACT FROM AUTHOR]

Curved or planar discordant surfaces occurring within a limited stratigraphic range immediately beneath shallow marine deposits represent penecontemporaneous shear surfaces along which slumps have moved. Rotated packets of strata frequently retained within the curved discordant surfaces show both internal and external evidence of having moved laterally. Movement is considered to have been triggered off by a sudden shock or shocks which may have been either of sedimentary or tectonic origin. The slumping occurred at the change in gradient between slope and shallow marine shelf deposits. [ABSTRACT FROM AUTHOR]

The crystallinity and mineralogy of both the glauconite and the clay fraction of samples from six contemporary marine environments were investigated by X-ray diffraction. In those areas where glauconite is now forming, the mineralogy and the degree of crystallinity of both the glauconite pellets and the associated clay fraction are similar. In contrast, detrital and relic glauconites are observed to have mineralogies that are different from their clay fractions. No consistent relationship was observed between degree of crystallinity and color of the pellets. Further, only two classes of glauconite as defined by BuRsT (1958) were common: expandable, interlayered clays and two or more clay minerals in a mixed assemblage. Based on the clay fraction-glauconite similarities and other supporting evidence, glauconite on the Scotia Ridge is concluded to be authigenic. Glauconite from Santa Monica Bay, California and from the continental shelf off Morocco appear to be detrital. Glauconite pellets in the shelf sediments off Guinea and the southeastern Atlantic Shelf of the United States are both detrital and authigenic. The poor crystallinity exhibited by the Chatham Rise glauconite is in contrast to the well-crystallized associated clay fraction and indicates that they are not genetically related. However, the origin of this glauconite remains in doubt. [ABSTRACT FROM AUTHOR]