GRGC: Developing an Absolutely-Dated Holocene Tree-Ring Chronology from Subfossil Huon Pine in Tasmania for Paleoclimatic and Isotopic Studies

9310093库克这项为期3年的提案是为了提供资金，继续利用在澳大利亚塔斯马尼亚西部收集的活的Huon松树和亚化石原木，开发连续的、绝对过时的全新世树轮年代学。迄今取得的进展包括：编制了两个距今2,000多年的Huon Pine年轮绝对年代表，从其中一个系列恢复了自公元前300年以来塔斯马尼亚州暖季气温，在4-6000年BP范围内编制了两个漂浮的亚化石年轮年表，以及从斯坦利河泛滥平原挖掘出105个新的Huon Pine亚化石原木。其中六个新测井的放射性碳测年表明年龄为4-7,000年BP，另外两个测井的日期在30,000年BP范围内。后两个都有数百个年轮，是迄今发现的最古老、保存完好的亚化石木材之一，证明塔斯马尼亚存在上一个冰河时代的可回收的Huon松木。因此，一个连续的树轮年表的发展追溯到晚更新世是一种非常现实的可能性。这次收集的大量木材和拟议的新收集最终将用于同位素分析，并可能将高精度的放射性碳校准曲线延长到最后一个冰河时代。在接下来的三年里，我们将对手中的亚化石木材进行加工，将现有的树木年轮年表追溯到过去，并继续从塔斯马尼亚西部地区收集更多的亚化石Huon松木。此外，我们将为塔斯马尼亚开发新的和扩展的气候重建，包括可能将暖季温度重建延长到公元前2,000年。

9310093 Cook This 3-year proposal is for funding to continue the development of a continuous, absolutely-dated Holocene tree-ring chronology from live Huon pine trees and sub-fossil logs collected in western Tasmania, Australia. Progress to date includes the development of two absolutely-dated Huon pine annual tree-ring chronologies extending back over 2,000 years from the present time, the reconstruction of warm-season Tasmanian temperatures since 300 BC from one of these series, the development of two floating, sub- fossil tree-ring chronologies in the 4-6,000 years BP range, and the excavation of 105 new sub-fossil Huon pine logs from the Stanley River flood plain. Radiocarbon dates of six of these new logs indicates ages of 4-7,000 yrs BP, plus two other logs with dates in the 30,000 yrs BP range. The latter two, each containing several hundred rings, are among the oldest, well-preserved, sub- fossil logs yet discovered anywhere and are proof that recoverable Huon pine wood from the last glacial epoch is present in Tasmania. Consequently, the development of a continuous tree-ring chronology extending back into the late-Pleistocene is a very real possibility. The bulk wood from this collection and the proposed new collections will eventually be used for isotopic analyses and the likely extension of the high-precision radiocarbon calibration curve back into the last glacial epoch. Over the next three years, we will process the sub-fossil wood now in hand, extend the existing tree-ring chronology back in time, and continue to collect more sub-fossil Huon pine wood from area in western Tasmania. In Addition, we will develop new and extended climatic reconstructions for Tasmania, including the probable extension of the warm-season temperature reconstruction back to 2,000 BC.