近日，美国亚利桑那大学Paul Kapp团队报道了青藏高原被风吹沙覆盖：对碎屑物源研究的启示。这一研究成果于2025年11月3日发表在《地质学》杂志上。

研究组在藏南雅鲁藏布江缝合带西段的小型汇水区（0.4-16.0 km²）采集了现代砂样。锆石年龄中有相当部分（29%-45%）为始新世至中新世，这些年龄虽年轻于古生代至古近纪的基岩，却与当地现代河流砂中的锆石年龄相符。研究区部分地段存在的风成沙丘、沙席以及广泛分布的<21 ka黄土状土壤覆盖层表明，自末次盛冰期以来，沉积物通过风动力作用从河床向斜坡上方传输。

青藏高原上黄土状土壤广泛分布，其在小型汇水区的保存优势表明黄土沉积速率已超越下伏基岩的侵蚀速率。小型汇水区（<50 km²）更能有效识别风力在沉积物搬运中起主导作用的情形。该案例研究揭示了风力引起的沉积物上坡传输机制，并彰显了藏南黄土在碎屑物质研究中的重要地位。

附：英文原文

Title: The Tibetan Plateau is covered in wind-blown sand: Implications for detrital provenance studies

Author: Kathryn Metcalf, Paul Kapp

Issue&Volume: 2025-11-03

Abstract: We sampled modern sand from small (0.416.0 km2) catchments within the western Yarlung suture zone of southern Tibet. Many (29%45%) of the zircon ages are Eocene to Miocene, younger than the Paleozoic to Paleogene bedrock but consistent with zircon ages in local modern river sands. Eolian dunes and sand sheets in part of the study area, and a widespread <21 ka loessic soil mantle, suggest that sediment was transported upslope out of the riverbeds by eolian processes since the Last Glacial Maximum. Loessic soil is ubiquitous on the Tibetan Plateau, and its preservation and dominance in small catchments suggests that loess deposition outpaces erosion of the underlying bedrock. Small (<50 km2) catchments may better identify when wind plays a significant role in sediment transport. Our case study highlights the efficacy of uphill sediment transport by wind and the detrital significance of loess in southern Tibet.

DOI: 10.1130/G53981.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article-abstract/doi/10.1130/G53981.1/666389/The-Tibetan-Plateau-is-covered-in-wind-blown-sandredirectedFrom=fulltext