The alluvial terrace
soils were degraded in a tropical climate for thousands of years.
The Upper Pleistocene alluvial terrace deposits of the Quaternary alluvial sediments of the Alto Guadalquivir Basin (SE Spain) provide an excellent example of how geomorphological evolution can exert an important control on mineral and geochemical signatures of sediments in a tectonically active area (Baena 1993; Garcia-Tortosa et al.
The main goals of this study are (1) to describe the nature and distribution of the alluvial terrace deposits of the Quaternary alluvial sediments of the Alto Guadalquivir Basin (SE Spain) based on sedimentary facies as well as on mineral and geochemical evidence, (2) to identify and discriminate different sediment sources of the Guadalquivir River alluvial deposits, (3) to estimate the potential factors that control the observed changes in the mineralogy and geochemistry within the different studied sedimentary sequences, and (4) to propose a terrace deposit model in the light of processes that have interacted to form the terrace sediments.
The bedrock on dam site composes of sequences of marl, mudstone with reddish brown and gray sandstone with silty-marl and greenish silt related from upper red formation (URF), while the abutments covered with old alluvial terrace
Until Ruth Shady decided to investigate what lay beneath the massive piles of earth looming up on the alluvial terrace
bordering the Supe Valley, they had attracted little attention from archeologists.
Three valley fill and four alluvial terrace
units are recognized from Holocene and late Pleistocene sediments in the lower Nueces River valley where this river is entrenched in the late Pleistocene Beaumont Formation.
Pleistocene-Holocene Sakhi Sarwar Group represents Dada (conglomerate) and Sakhi Sarwar (clays, sandstone and conglomerates) formations; alluvial terraces
, fans and alluvial plains.
State 2: Young deposits of alluvial fans and alluvial terraces
, made up of sediments gravity and stream flows (in smaller proportion), with maximum thickness of 7 m, maximum axial lengths of 3 km and slopes between 6[grados] and 18[grados].
One of the current projects, on the Akposso Plateau, is a search for diamonds, which have been recovered by small miners from the alluvial terraces
A study by the United Nations in the 1980s and a follow up study by the SYSMIN I project in late 1990's, conclusively shows the presence of alluvial gold in gravels at or near the bottom of ancient alluvial terraces
The diamondiferous gravels form part of elevated alluvial terraces
which continuously border both banks of the river occupying the central part of the property.
Under the heading "Future Developments", the poster notes "The Indian River alluvial terraces
represent a previously unrecognized, undervalued resource, with significant economic values of gold.