Holocene stable-isotope stratigraphy at Lough Gur, County Limerick, Western Ireland
Holocene stable-isotope stratigraphy at Lough Gur, County Limerick, Western Ireland
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爱尔兰西部利默里克郡古尔湖的全新世稳定同位素地层学
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
E. Ito
中科院分区：
文献类型：
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作者：
K. Ahlberg;Elisabeth Almgren;H. E. Wright;E. Ito
在经历了新仙女木期δ 18 O的4‰波动和北震前的1‰下降之后，δ 18 O值从9300年到8000年的14 C BP（uncal）从-2.5 ‰稳定地下降到-5.3‰。全新世早期下降了近3‰，这是降水温度下降近6°C的结果。晚冰期和北寒武纪前（12000-9300年BP uncal）大部分地区的高温。可能反映了与更大的日照有关的温暖的夏天和劳伦特冰盖对大气环流的影响所造成的温暖的冬天。8000年BP后，一个不整合面中断了层序，但在约5000年BP后，δ 18 O和δ 13 C是不规则的，因为湖平面较低，如沿岸的岩芯中出现的沿岸的贝壳和木质碎屑所示，以及人为因素，如从沿岸的和近海岩芯中发现的森林干扰和农业的花粉指标推断。
After the pronounced fluictuation of 4‰ in δ18O during the Younger Dryas and the 1‰ dip during the Preboreal Oscillation, values for δ18O decreased very steadily from -2.5 to -5.3‰ from 9300 to about 8000 14C yr BP (uncal.). This early-Holocene decrease of almost 3‰ is interpreted as a result of a declinle of almost 6°C in the temperature of precipitation. The previous high temperature of much of the Lateglacial and the Preboreal (12000-9300 yr BP uncal.) may reflect warm summers related to greater insolation and warm winters caused by the influence of the Laurentide ice sheet on atmospheric circulation. After 8000 yr BP a disconformity interrupts the sequence, but after about 5000 yr BP the δ18O and δ13C are irregular because of a low lake level, as shown by the occurrence of littoral shells and woody detritus in the littoral core, and because of anthropogenic factors, as inferred from pollen indicators of forest disturbance and farming found in both the littoral and offshore cores.