Paleoenvironments during Younger Dryas- E arly Holocene retreat of the Greenland Ice Sheet from outer Disko Trough, central west Greenland
Paleoenvironments during Younger Dryas- E arly Holocene retreat of the Greenland Ice Sheet from outer Disko Trough, central west Greenland
复制标题
新仙女木期的古环境——全新世早期格陵兰冰盖从格陵兰岛中西部迪斯科海槽外撤退
DOI：
10.1002/jqs.2652
复制
发表时间：
2013
影响因子：
2.3
通讯作者：
JENNINGS A
中科院分区：
文献类型：
--
作者：
JENNINGS A
通过对上斜坡（JR175-VC35）和外陆架（JR175-VC20和HU2008029-070CC）的放射性碳测年沉积物岩心进行岩相、有孔虫、甲虫和沉积物来源分析，研究了新仙女木期晚期到全新世早期格陵兰冰盖从格陵兰岛西部迪斯科海槽系统外陆架退缩期间的古环境。核心数据显示，冰缘因崩解而从外陆架迅速后退，在寒冷的古海洋条件下从 12.2k cal a BP 开始，海冰持续长达 11 个月。 10.9k cal a BP 处的冰层正在向 Disko Bugt 退缩。迪斯科布格特和格陵兰岛西海岸其他地方的冰盖消融加剧，是根据与外陆架 10.9 至 9.5k cal a BP 之间的高沉积率相关的寒冷冰川海洋条件推断的。在 7.8k cal a BP 之前，外陆架上的冰川海洋状况都有记录。在11.6至10.6k cal a BP之间沉积的富含>2毫米碎屑的碎屑碳酸盐沉积物表明，从巴芬湾北部冰缘崩解的冰山正在融化，并沿着西格陵兰岛释放沉积物，而格陵兰冰盖边缘正在退缩到迪斯科布格特。
Paleoenvironments during the late Younger Dryas through early Holocene retreat of the Greenland Ice Sheet from the outer shelf in the Disko Trough system of central West Greenland were investigated via lithofacies, foraminifera, dinocysts and sediment provenance analyses in radiocarbon‐dated sediment cores from the upper slope (JR175‐VC35) and outer shelf (JR175‐VC20 and HU2008029‐070CC). Core data show that the ice margin retreated rapidly from the outer shelf by calving, beginning by 12.2k cal a BP under cold paleoceanographic conditions with up to 11 months of sea‐ice. Ice retreat into Disko Bugt was well underway by 10.9k cal a BP. Enhanced ice‐sheet ablation in Disko Bugt and elsewhere along the West Greenland coast is inferred from cold glacial marine conditions associated with high sedimentation rates between 10.9 and 9.5k cal a BP on the outer shelf. Glacial marine conditions are recorded on the outer shelf until 7.8k cal a BP. Detrital carbonate‐bearing sediments rich in >2‐mm clasts deposited between 11.6 and 10.6 k cal a BP indicate that icebergs calved from northern Baffin Bay ice margins were melting and releasing sediments along West Greenland while the Greenland Ice Sheet margin was retreating into Disko Bugt.