In recent years there has been a renewed interest in the problem of unraveling the various possible causes of allocyclic variability in alluvial basin fills (e.g. tectonics, climate, subsidence, eustasy). One approach to this problem has been the development of quantitative, physically based models for the filling of sedimentary basins, but these models have already evolved well beyond the data available to test and refine them. There is a continuing need for new high-resolution data sets that can be used to evaluate the basic predictions of these models. The main goal of this project is to produce such a data set from the superbly exposed Tertiary alluvial systems of the SE margin of the Ebro Basin, Spain. PI's will collect closely spaced paleomagnetic sections and measurements of gravel distribution and channel characteristics in three dimensions, in at least two adjoining alluvial fans of different sizes. These data, together with ongoing modeling efforts, by the PI's will provide insight on how various causes of allocyclic progradation can be distinguished and in particular on the identification of true "syntectonic" conglomerates.
