Thermochronometry reveals headward propagation of erosion in an alpine landscape.
نویسندگان
چکیده
Glacial erosion of mountain ranges produces spectacular alpine landscapes and, by linking climate with tectonics, influences a broad array of geophysical phenomena. Although the resultant landforms are easily identified, the timing and spatial pattern of topographic adjustment to Pleistocene glaciations remain poorly known. We investigated topographic evolution in the archetypal glacial landscape of Fiordland, New Zealand, using (U-Th)/He thermochronometry. We find that erosion during the past 2 million years removed the entire pre-Pleistocene landscape and fundamentally reshaped the topography. Erosion focused on steep valley segments and propagated from trunk valleys toward the heads of drainage basins, a behavior expected if subglacial erosion rate depends on ice sliding velocity. The Fiordland landscape illustrates complex effects of climate on Earth's surface morphology.
منابع مشابه
Project Description: Antarctic Peninsula Exhumation and Landscape Development Investigated by Low-temperature Detrital Thermochronometry
I. Overview and introduction. We propose to apply methods of low-temperature thermochronometry based on the (U-Th)/He system in apatite to investigate the exhumation history, the development of the present topography, and the pattern of glacial erosion in the central Antarctic Peninsula. Recent studies have used this approach to study the dramatic, high-relief landscapes formed by Pleistocene a...
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عنوان ژورنال:
- Science
دوره 332 6025 شماره
صفحات -
تاریخ انتشار 2011