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Geochemical analyses of marginal basin sediments (Golfo San Matias, Argentina) for Ca, Mg, Sr, Co, Ni, V, Ti, Cr, Fe, Cu, Zn, and Mn in the total sediments and their carbonate fractions have yielded distinct halistases, the areal dispositions of which must be controlled by processes operating within the basin. One of the most important of these processes is derived from hydrodynamic forces moving the sedimentary particles and depositing them in rather distinct (at the 1-phi interval) granulometric zones.

For the total sample analyses, there are covariant relations between the dominant granulometric fractions and certain elements (for example, Zn with clay size, Ti with fine-sand size). For other elements, correlations are less definitive (for example, Fe).

Fragmented biogenic material is ubiquitous in the basin sediments but shows strong accumulations in some zones as a result of localized sources and dominant current activity; there is an expected positive correlation between Ca, Mg, and Sr, and the quantity of carbonate material in the sediments, and the distribution of Co appears to be directly influenced by biogenic components.

In the study basin, the disposition and shape of the plotted halistases are determined by the mode of migration of the elements, in solution, as hydrolysates, as resistates, and as biodates. Although homogenization drives exist, localized conditions have been more influential in controlling detrital and elemental distributions and dispersions. Selected elements are examined for their utility in serving as discriminants better to interpret similar data from the geologic column.

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