No valley deepening of the Tatra Mountains (Western Carpathians) during the past 300 ka

Abstract

Wet-based mountain glaciers are efficient agents of erosion, which leads to the assumption that each glacial episode results in successive valley deepening. The tendency of subsequent glaciations to obscure evidence of previous events makes it difficult to study the work done by past glacial episodes. Epiphreatic and paleophreatic caves that developed at or under the water table and dried out in response to valley deepening can serve as recorders of the valley incision history. U-series data from speleothems in the cave networks at the base of the present-day valleys in the Tatra Mountains (Western Carpathians) consistently yield the oldest ages of ca. 325 ka. While speleothem ages are typically phreatic-vadose transition minimum ages, they nonetheless unequivocally demonstrate that neither glacial valley deepening nor fluvial incision occurred over the past 300 ka, unlike the successive valley deepening over the same period in the adjacent Alps.