DISTINGUISHING REGIONAL AND LOCAL PALEOENVIRONMENTAL SIGNALS: COMPARING PALEOHYDROLOGIC CHANGE AND BASIN RESPONSE FROM TWO PALEOLAKES ON THE JORDAN PLATEAU

In discussing proxy records and their implications for changes in paleoenvironment, much debate has centered around distinguishing between the scale of climate signals- global, regional, or local. Much of this debate in the Middle East has been driven by the extrapolation of proxy records from extra-local sources to explain local environmental history. Proxy records from areas that have very different environments today- Turkey, Egypt, and the Rift Valley- Dead Sea, Huleh and Ghab basins, have been used to explain the paleoenvironments on the Jordan Plateau. This is in part due to the lack, until recently, of local long-term local proxy records.

The issue of scale in regional and local paleoenvironment signals is explored by comparing the paleoenvironmental histories of two critical wetlands, the Azraq basin and the Qa’ el-Jafr. The wetlands are located at the northern and southern edges of the Central Jordan Plateau. Their sedimentary records attest to long histories of hydrologic fluctuation. Yet both basins have significantly different sedimentation histories that indicate very different responses to hydrologic change. Sedimentary and geochemical analyses of 51 m and 31 m sediment cores, respectively, allow identification of multiple changes in sedimentation regime indicative of major shifts in paleohydrology and paleoenvironment. Radiocarbon, Infrared Stimulated Luminescence, and relative calcium carbonate development provide a variety of methods of age determination for the correlation of both cores.

These new, long-term proxies record regional and local responses to changes in paleoenvironment. They provide important context for exploring scalar issues of regional environmental change and yield important indications for connection to adjoining regions.