ANNUAL GROWTH BANDING IN A CAVE STALAGMITE
ANNUAL GROWTH BANDING IN A CAVE STALAGMITE
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DOI：
10.1038/364518a0
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发表时间：
1993-08-05
期刊：
影响因子：
64.8
通讯作者：
RICHARDS, DA
中科院分区：
文献类型：
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作者：
BAKER, A;SMART, PL;RICHARDS, DA
在洞穴方解石沉积物（洞穴沉积物）中存在的显微发光带最近已被证实1 -3。发光似乎是由来自上覆土壤的腐殖酸和富里酸的激发引起的，随后被纳入方解石3，4。我们已经测试了这种发光是否对应于每年的增长层，使用高精度热电离质谱U-238-U-234-U-Th-230年龄从带状部分的全新世石笋。我们在这里报告说，由计数带产生的时间跨度，假设他们是一年，同意在误差范围内与我们的铀钍定年所获得的。这表明，带状是一年一次的，应该使带状洞穴沉积物的宝贵资源，提供高分辨率的记录，过去的气候（其中降水量可以估计从生长率5，6和温度从稳定同位素测量7）和太阳-地球的相关性（发光强度可以与太阳黑子周期1 -3）。
THE presence of microscopic luminescence banding in cave calcite deposits (speleothems) has recently been reported1-3. The luminescence seems to be caused by excitation of humic and fulvic acids derived from the overlying soil and subsequently incorporated into the calcite3,4. We have tested whether such luminescence corresponds to annual growth layers, using high-precision thermal-ionization mass-spectrometric U-238-U-234-U-Th-230 ages from banded sections of a Holocene stalagmite. We report here that the timespans yielded by counting bands, on the assumption that they are annual, agree within error limits with those obtained by our uranium-thorium dating. This demonstration that the banding is annual should make banded speleothems valuable resources for providing high-resolution records of past climate (in which precipitation can be estimated from growth rates5,6 and temperatures from stable-isotope measurements7) and solar-terrestrial correlations (as the luminescence intensity can be related to the solar sunspot cycle1-3).