Reconstructing and interpreting past hydrological system changes from the Quaternary sediment-landform record presents many challenges especially when trying to establish causality. In such circumstances attempting to isolate individual drivers is perhaps unrealistic and thus inferences are made with respect to the combined influence of multiple controls and constraints. In this paper we seek to interpret the landscape responses recorded in the sediment-landform record of the Early Pleistocene Gediz valley, western Turkey, within the context of interacting geodynamic and hydrodynamic system changes. Our earlier work on the Gediz sequence established the presence of a rich fluvial archive constrained by a comprehensive geochronology from overlying lava flows. Repeated damming of the Gediz valley floor and consequent re-routing of water flow, testifies to a direct connection between fluvial activity and volcanism. This volcanism has been linked to regional tectonic extension with regional uplift promoted as a major driver of the progressive river incision of the Gediz River over the Quaternary. This incision has been punctuated by periods of deposition dictated by sediment and water budgets controlled principally by fluctuating climate and consequent vegetation change. Recently however, the significance of more local fault movements and fracturing has been recognised and here we examine and attempt to quantify these geodynamics in greater detail. In addition, we examine and describe, for the first time, extensive associated travertine deposits. Isotopic analysis of these travertines confirms their thermogenic origin and directly links their creation to the faulting/fracturing, volcanism and the recycling of calcium-rich groundwater. The formation of mounds and sheets extend onto their contemporary valley floors, thus directly connecting the fluvial and travertine archives and allowing linkage between surface and subsurface hydrological change. By utilising both the fluvial and travertine archives a more complex picture of landscape evolution emerges. The youngest terraces (
School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom; Faculty of Geo-Information Science and Earth Observation (ITC), Twente University, Enschede, Netherlands; Akdeniz University, Faculty of Letters, Geography Department, Konyaaltı, Antalya 07058, Turkey; Department of Geography, Harran UniversitySanliurfa 63300, Turkey; Soil Geography and Landscape group, Wageningen University, P.O. Box 47, Wageningen, NL-6700AA, Netherlands; School of Geography and Environment, University of Southampton, Southampton, SO17 1BJ, United Kingdom; School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, B15 2TT, United Kingdom
Recommended Citation:
Maddy D.,Veldkamp A.,Demir T.,et al. Early Pleistocene River Terraces of the Gediz River, Turkey: The role of faulting, fracturing, volcanism and travertines in their genesis[J]. Geomorphology,2020-01-01,358