A new Greenland ice core chronology for the last glacial termination
A new Greenland ice core chronology for the last glacial termination
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DOI：
10.1029/2005jd006079
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发表时间：
2006-03-21
影响因子：
4.4
通讯作者：
Ruth, U
中科院分区：
文献类型：
--
作者：
Rasmussen, SO;Andersen, KK;Ruth, U
[1]我们提出了一个新的共同的地层时标的北格陵兰冰芯项目（NGRIP）和GRIP冰芯。时间跨度为距今7.9 - 14.8 kyr，包括Bolling、Allerod、Younger Dryas和全新世早期。我们使用新的和以前发表的数据相结合，最突出的是新的高分辨率连续流分析（CFA）的NGRIP冰芯杂质记录。一些研究者已经使用多参数方法识别和计算了年层，估计全新世部分的最大计数误差高达2%，较老部分约为3%。这些计数误差估计反映了难以解释的年度层的数量，但不是用于年度层识别的规则集的可能偏差。由于GRIP和NGRIP冰芯在全新世中晚期的年层计数中不是最佳的，因此时间尺度与8.2 kyr冷事件中的一个突出的火山事件有关，最近在DYE-3冰芯中测得的日期为公元前8236年。D. 2000年（b2 k），最大计数误差为47年。新的时间表将新仙女木-北半球过渡期定在11，703 b2 k，比目前的GRIP和NGRIP时间表早100 - 150年。过渡的年龄在几年内与GISP 2的时间尺度相匹配，但从整个7.9 - 14.8 kyr部分来看，新的时间尺度与GISP 2的时间尺度之间存在显着差异。从冰川到Bolling interstadial的过渡可以追溯到14，692 b2 k。所提供的时间尺度是新的格陵兰冰芯年表的一部分，该年表与DYE-3、GRIP和NGRIP冰芯共有，名为2005年格陵兰冰芯年表（GICC 05）。年层厚度被观察到具有良好的近似性的对数正态分布，并与全新世早期相比，在新仙女木期和博林期的平均积累率分别为47 +/- 2%和88 +/-2%。
[1] We present a new common stratigraphic timescale for the North Greenland Ice Core Project (NGRIP) and GRIP ice cores. The timescale covers the period 7.9 - 14.8 kyr before present and includes the Bolling, Allerod, Younger Dryas, and early Holocene periods. We use a combination of new and previously published data, the most prominent being new high-resolution Continuous Flow Analysis (CFA) impurity records from the NGRIP ice core. Several investigators have identified and counted annual layers using a multiparameter approach, and the maximum counting error is estimated to be up to 2% in the Holocene part and about 3% for the older parts. These counting error estimates reflect the number of annual layers that were hard to interpret, but not a possible bias in the set of rules used for annual layer identification. As the GRIP and NGRIP ice cores are not optimal for annual layer counting in the middle and late Holocene, the timescale is tied to a prominent volcanic event inside the 8.2 kyr cold event, recently dated in the DYE-3 ice core to 8236 years before A. D. 2000 (b2k) with a maximum counting error of 47 years. The new timescale dates the Younger Dryas-Preboreal transition to 11,703 b2k, which is 100 - 150 years older than according to the present GRIP and NGRIP timescales. The age of the transition matches the GISP2 timescale within a few years, but viewed over the entire 7.9 - 14.8 kyr section, there are significant differences between the new timescale and the GISP2 timescale. The transition from the glacial into the Bolling interstadial is dated to 14,692 b2k. The presented timescale is a part of a new Greenland ice core chronology common to the DYE-3, GRIP, and NGRIP ice cores, named the Greenland Ice Core Chronology 2005 (GICC05). The annual layer thicknesses are observed to be log-normally distributed with good approximation, and compared to the early Holocene, the mean accumulation rates in the Younger Dryas and Bolling periods are found to be 47 +/- 2% and 88 +/- 2%, respectively.