Clumped isotope thermometry of modern and fossil snail shells from the Himalayan-Tibetan Plateau: Implications for paleoclimate and paleoelevation reconstructions

Abstract Carbonate clumped isotope thermometry has been applied to fossil mollusk shells from Tibet reconstruct the paleoclimate and paleoelevation of region. However, inferred climatic conditions this proxy are inconsistent with paleontological evidence. Here, we report new data both modern (5–4 Ma) freshwater results X-ray diffraction (XRD) analyses Himalayan-Tibetan Plateau. Although all analyzed in study appeared pristine based on visual inspection, XRD reveal that more than half these apparently “pristine” contain trace amounts calcite. Clumped temperatures derived display a large range variation (>22 °C). Among analyzed, those containing traces calcite have yielded average ?10 °C lower no detectable same strata. These observations suggest alteration can occur aragonite low-temperature environments even visible signs only The 4 higher shells, indicating southwest was warmer 4–5 Ma today. After accounting for temperature change due global cooling, difference between suggests southwestern Tibetan Plateau Pliocene similar its present-day elevation.