Mid‐Holocene sub‐blanket‐peat alluvia and sediment sources in the upper Liffey valley, Co. Wicklow, Ireland
Mid‐Holocene sub‐blanket‐peat alluvia and sediment sources in the upper Liffey valley, Co. Wicklow, Ireland
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爱尔兰威克洛县利菲河谷上游的全新世中期亚覆盖泥炭冲积土和沉积物来源
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
P. Glanville
中科院分区：
文献类型：
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作者：
M. Thorp;P. Glanville
描述了最近在威克洛郡上利菲河谷希尔赛德上的区域毯状泥炭下埋藏的一级河谷暴露剖面。该剖面显示，在区域性冰碛和风化花岗岩上方有一条广泛的大圆石和石线，其下为浅河谷形式内的两个冲积层。冲积层木材的~（14）C测年表明，较老的冲积层形成于4324 ± 53 ~ 4126 ± 45 BP之间，较年轻的冲积层形成于3217 ± 53 ~ 2975 ± 53 BP之间。上覆泥炭的基底层测得的年代为2208 ± 61 BP。较年轻的冲积层显示了泥炭扩张前土壤沼泽化的影响。在上游集水区其他地方的年代花粉分析证实，4000-3600 BP后，毯状泥炭在350米以上的大部分地区蔓延。在覆盖泥炭在集水区上延伸之前，埋藏的山谷为上利菲山谷的中全新世冲积平原提供了沉积物，之后，来自它和其他集水区斜坡的沉积物产量下降。版权所有© 2003年约翰威利父子有限公司。
A recently exposed section across a first‐order valley buried beneath the regional blanket peat on hillside slopes in the upper Liffey valley, Co. Wicklow, is described. The section shows two alluvia within a shallow valley form underlain by an extensive boulder and stone line over regional till and weathered granite. 14C dates from wood in the alluvia indicate the older alluvium to have formed between 4324 ± 53 BP and 4126 ± 45 BP and the younger between 3217 ± 53 BP and 2975 ± 53 BP. The basal layer of the overlying peat yielded a date of 2208 ± 61 BP. The younger alluvium shows the effects of soil paludification prior to the peat expansion. Dated pollen analyses elsewhere in the upper catchment confirm the spread of blanket peat over most areas above 350 m after 4000–3600 BP. The buried valley was contributing sediments to the mid‐Holocene floodplains in the upper Liffey valley prior to the extension of blanket peat over the catchment after which sediment yields from it and the other catchment slopes declined. Copyright © 2003 John Wiley & Sons, Ltd.