SGER: Sclerosponges: a key to understanding the influence of global warming on ocean thermocline and mixed layer variability..an example from the Caribbean

摘要：文石化石是一类独特的热带生物，它们在近地表到200米的栖息地范围内分泌文石骨架。由于文石化石可以存活1000年，而且它们的文石地球化学与海水处于同位素平衡状态，因此这些骨骼包含了全新世连续的近地表环境条件的宝贵档案。当从一套样品中收集氧同位素和微量元素数据时，就有可能重建作为深度和时间函数的水柱温度和盐度。来自该SGER的资金将用于在波多黎各Desecheo岛200米深的横断面上利用混合气体/呼吸器潜水技术(至100米)和水下机器人(100-200米深度)定位和收集硬壳虫。加勒比海珊瑚礁研究所将为该项目提供ROV，NSF不承担任何费用。收集的硬壳岩将使用U/Th测年，并对其骨骼地球化学进行分析，以校准和验证用于古温度测定的地球化学替代物。

Abstract: Sclerosponges are a unique group of tropical organisms that secrete aragonite skeletons across a habitat range from the near surface to 200 m. Because sclersosponges can live for 1000 years, and their aragonite geochemistry is in isotopic equilibrium with seawater, the skeletons contain an invaluable archive of continuous near surface environmental conditions during the Holocene. When oxygen isotope and trace element data are collected from a suite of specimens, it is possible to reconstruct water column temperature and salinity as a function of depth and time. Funds from this SGER will be used to locate and collect sclerosponges from a 200 m depth transect along Desecheo Island, Puerto Rico, using mixed-gas/rebreather diving technology (to 100 m) and an ROV (100-200 m depth). The Caribbean Coral Reef Institutes will provide the ROV to this project at no cost to NSF. Collected sclerosponges will be dated using U/Th and analyzed for their skeletal geochemistry to calibration and validate the geochemical proxies for paleothermometry.