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在对莱州湾南岸8个钻孔沉积物沉积结构及有孔虫特征分析基础上,识别相关海面标志层位,辅以加速器质谱AMS14C测年,重建了全新世相对海面变化历史,并讨论了海面变化的沉积响应及控制因素。约9200cal BP以前,海面快速上升,研究区海侵时海面于-21.5m左右;9200~8400cal BP海面上升速率减缓至约2mm/a;8400~8000cal BP海面由-14m快速上升至-5.5m,速率约为33mm/a;8000~7600cal BP,海面持续数百年停滞或微弱下降;7600~7000cal BP海面由-5.5m快速上升至0m以上,速率至少约为13mm/a;7000~6000cal BP海面缓慢上升至+2~+3m位置,速率约为3mm/a;约6000cal BP以后海面缓慢下降至现今水平。约9200cal BP以前、8400~8000cal BP、7600~7000cal BP时期的3次海面快速上升,是MWP-1C融水脉冲、诱发8.2ka冷事件的融水脉冲,以及MWP-2融水脉冲的中纬度地区响应。中全新世全球冰融趋于停滞后,由于研究区沉积盆地沉降速度较慢,在冰川均衡调整效应下,使+2~+3m的相对高海面得以呈现。
Based on the analysis of the sedimentary structures and foraminiferal characteristics of 8 boreholes in the south of Laizhou Bay, the related sea surface markers were identified and analyzed by accelerator mass spectrometry AMS14C dating. The history of relative sea surface changes during the Holocene was reconstructed. Changing depositional response and controlling factors. Before 9200cal BP, the sea surface increased rapidly. The sea surface sea level in the study area was -21.5m. The sea surface rate of 9200-8400cal BP slowed down to about 2mm / a. The sea surface velocity increased rapidly from -14m to -5.5m at 8400 ~ 8000cal BP, A rate of about 33mm / a; 8000 ~ 7600cal BP, the sea surface stagnates or weakly declines for hundreds of years; the sea surface of 7600 ~ 7000cal BP rises rapidly from -5.5m to above 0m at a rate of at least 13mm / a; Slowly rose to +2 ~ +3 m position, the rate of about 3mm / a; about 6000cal BP after the sea slowly declined to the present level. The mean sea level rise rapidly at about 9200cal BP, 8400 ~ 8000cal BP and 7600 ~ 7000cal BP, which is the MWP-1C meltwater pulse, the meltwater pulse induced by 8.2ka cold event, and the mid-latitude of MWP-2 meltwater pulse Regional response. After the global ice melting became stagnant in the middle Holocene, due to the slow sedimentation rate in the sedimentary basins of the study area, the relatively high sea level of +2 to +3 m was presented under the effect of glacial-equilibration adjustment.