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Precise dating of East-Asian-Monsoon D/O events during 95―56 ka BP:Based on stalagmite data from Shanbao Cave at Shennongjia,China 被引量:4
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作者 XIA ZhiFeng KONG XingGong +1 位作者 JIANG XiuYang CHENG Hai 《Science China Earth Sciences》 SCIE EI CAS 2007年第2期228-235,共8页
Based on 23 U/Th analyses and 532 oxygen isotopic data, an averaged 80-a stalagmite oxygen isotopic composition series was established through 95 to 56 thousand years before present (ka BP) from two speleothems in Sha... Based on 23 U/Th analyses and 532 oxygen isotopic data, an averaged 80-a stalagmite oxygen isotopic composition series was established through 95 to 56 thousand years before present (ka BP) from two speleothems in Shanbao Cave, Shennongjia, central China. Shanbao Cave record (referred to as SB record) replicates well with Hulu Cave record, extending the characteristics of millennial oscillations in East-Asian-Summer-Monsoon (EASM) to the past 95 ka. The trend of the SB record generally follows mid-July solar insolation at 65°N, suggesting that mid-high northern latitude insolation, in the first or- der, controls changes of EASM intensity. Millennial oscillations of EASM recorded in the stalagmites are well related to the Greenland interstadials referred to as Dansgaard/Oeschger (D/O) events from 1 to 22, indicating that rapid ocean-atmosphere reorganization in North Atlantic has a remote effect in EASM. The well-dated D/O events by stalagmites probably provide an absolute calibration for chro- nologies of Greenland ice cores. The timings of D/O events in the SB record are different variously from those in Greenland ice cores. For D/O 19 and 20, the age offsets between the stalagmites' and the Greenland ice cores' record are significant, larger than the uncertainties of uranium-series dating. The two events in the SB record are younger than those in North GRIP time scale by 1―2 ka, and older than the counterparts in GISP2 by approximately 3―4 ka. A comparison between the SB and Brazil stalag- mite record shows an anti-phase relation in millennial-scale monsoon precipitation between the two localities. This supports a mode for the coupled ocean-atmosphere "See-saw". 展开更多
关键词 the last glacial Shennongjia STALAGMITE Greenland ice cores timing of d/o event
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MIS3晚期东亚季风强度和DO事件年龄 被引量:32
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作者 赵侃 孔兴功 +1 位作者 程海 汪永进 《第四纪研究》 CAS CSCD 北大核心 2008年第1期177-183,共7页
基于神农架山宝洞石笋(SB46)的9个230Th年龄和326个氧同位素数据,建立了末次冰期32.2~26.7kaB.P.和17.0~15.4kaB.P.的东亚季风降水序列。该序列和同一洞穴全新世石笋记录的对比发现,在MIS3晚期东亚季风区可能存在极强夏季风降水事件,... 基于神农架山宝洞石笋(SB46)的9个230Th年龄和326个氧同位素数据,建立了末次冰期32.2~26.7kaB.P.和17.0~15.4kaB.P.的东亚季风降水序列。该序列和同一洞穴全新世石笋记录的对比发现,在MIS3晚期东亚季风区可能存在极强夏季风降水事件,相当于全新世季风强度,可能与岁差旋回太阳辐射及海陆水汽潜热释放增强有关。与葫芦洞石笋δ18O记录和格陵兰冰芯δ18O记录对比表明,东亚夏季风千年尺度气候振荡与高北纬地区海-气快速重组存在遥相关效应。山宝洞石笋年龄与葫芦洞石笋和格陵兰冰芯时标(SS09sea)在定年误差范围内基本一致,但山宝洞石笋与冰芯记录在DO事件的年龄、波形和持续时间上更为一致,不仅进一步说明了低纬季风气候与极地气温同步变化,而且有效地弥补了葫芦洞记录在这一时段的不足。 展开更多
关键词 MIS 3晚期 石笋 do事件 东亚季风
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川东北宋家洞高分辨率石笋δ^(13)C记录与D/O事件5-1 被引量:9
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作者 刘淑华 杨亮 +5 位作者 黄嘉仪 陈琳 陈琼 米小建 贺海波 周厚云 《地球化学》 CAS CSCD 北大核心 2015年第5期413-420,共8页
基于川东北宋家洞石笋SJ1的399个稳定碳同位素组成(δ13C)数据建立了末次冰期中晚期(14~43 ka)高分辨率δ13C时间序列。SJ1的δ13C变化与已发表的该石笋稳定氧同位素组成(δ18O)变化趋势非常一致,清晰地记录了该地区植被对D/O事件5-10... 基于川东北宋家洞石笋SJ1的399个稳定碳同位素组成(δ13C)数据建立了末次冰期中晚期(14~43 ka)高分辨率δ13C时间序列。SJ1的δ13C变化与已发表的该石笋稳定氧同位素组成(δ18O)变化趋势非常一致,清晰地记录了该地区植被对D/O事件5-10的敏感响应。东亚夏季风气候控制的地表植被(包括C3和C4植被比例C3/C4变化和植被密度变化)和土壤微生物活动变化可能是影响SJ1的δ13C变化的主要因素。在这些D/O事件发生时δ13C变轻,指示了C3/C4植被比例上升和植被密度增加。此外,受降水控制的岩溶地下水流速影响的水-岩相互作用,石笋表面滴水时间间隔、洞穴空气的CO2分压和洞穴通风效应等因素影响的CO2脱气作用和先期碳酸盐沉积也可能对SJ1的δ13C变化产生了影响。 展开更多
关键词 末次冰期中晚期 石笋 碳同位素 d/o事件 川东北
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山西临汾盆地末次冰期时段湖相沉积中的H、D/O事件记录 被引量:9
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作者 胡小猛 王杜涛 +2 位作者 陈美君 胡海晨 吴洁利 《第四纪研究》 CAS CSCD 北大核心 2014年第2期354-363,共10页
千伏村剖面是一沉积延续时间跨越末次冰期时期的湖相沉积剖面。论文利用S_1/L_1、L_1/S_0界线年龄及OSL测年数据建立了剖面的深度-年龄坐标系。根据早期形成的分别与气下黄土和古土壤层发育时代对应的、指示不同气候条件下的湖相沉积层... 千伏村剖面是一沉积延续时间跨越末次冰期时期的湖相沉积剖面。论文利用S_1/L_1、L_1/S_0界线年龄及OSL测年数据建立了剖面的深度-年龄坐标系。根据早期形成的分别与气下黄土和古土壤层发育时代对应的、指示不同气候条件下的湖相沉积层特征差异,论文遴选出小于4μm粘土组分含量、中值粒径(Md)、沉积物磁化率、有机质含量、Rb/Sr比值等参数作为区域气候指代参数。剖面系列气候指代参数的变化曲线显示,区域末次冰期期间出现了10个干冷期,发生时间分别在16.9ka B.P.,22.7ka B.P.,24.9ka B.P.,27.1ka B.P.,31.7ka B.P.,41.5ka B.P.,52.8ka B.P.,56.2ka B.P.,61.6ka B.P.和67.5ka B.P.;其中16.9ka B.P.,22.7ka B.P.,27.1ka B.P.,41.5ka B.P.,52.8ka B.P.和67.5ka B.P.可与北大西洋地区的HI^H6干冷期事件对应。剖面系列气候指代参数变化曲线也记录了区域18个暖湿事件,且这些事件可与北大西洋地区的D/O循环间冰阶事件对应。研究结果显示东亚地区末次冰期期间的气候高频波动可能与北大西洋地区存在某种联系。 展开更多
关键词 临汾盆地 千伏村剖面 沉积参数 HEINRICH事件 d o事件
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中国不同区域MIS-3时期气候特征研究进展 被引量:16
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作者 甄治国 钟巍 +2 位作者 薛积彬 郑琰明 刘伟 《冰川冻土》 CSCD 北大核心 2008年第5期814-824,共11页
在对比分析前人对MIS-3阶段气候环境特征的研究基础上,通过冰芯、石笋氧同位素与磁化率等各种代用指标,对中国不同区域在MIS-3时期的气候环境特征及其原因进行了探讨.结果表明:中国不同区域MIS-3阶段的气候环境特征在大背景较为一致的... 在对比分析前人对MIS-3阶段气候环境特征的研究基础上,通过冰芯、石笋氧同位素与磁化率等各种代用指标,对中国不同区域在MIS-3时期的气候环境特征及其原因进行了探讨.结果表明:中国不同区域MIS-3阶段的气候环境特征在大背景较为一致的条件下也存在一定的区域性差异.青藏高原在MIS-3阶段的早期(MIS-3c)和晚期(MIS-3a)较其它区域来说可能温度要高,降水量更为充沛,中期(MIS-3b)气候曾经一度变冷变干,存在着千年尺度的气候转换;东亚季风区主要以暖湿气候为主,西南季风区则以凉湿为主,而温湿的气候环境可能是MIS-3时期西北地区主要气候特征.区域对比研究还发现,Heinrich事件与D-O循环在中国不同地区同样着存在不少记录. 展开更多
关键词 MIS-3 气候变化 HEINRICH事件 d-o循环
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晚更新世60~90kaBP气候变化探讨 被引量:1
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作者 黄帆 杨勋林 +1 位作者 张银环 张月明 《湖北农业科学》 北大核心 2014年第3期544-549,共6页
60~90 kaBP是末次间冰期向末次冰期转换时期,此时段经历了许多重要的气候事件。对此进行深入研究有助于了解这些气候突变事件,为理解气候驱动机制提供新的视角。通过系统回顾60~90 kaBP洞穴石笋、极地冰芯等古气候载体的研究成果,探讨... 60~90 kaBP是末次间冰期向末次冰期转换时期,此时段经历了许多重要的气候事件。对此进行深入研究有助于了解这些气候突变事件,为理解气候驱动机制提供新的视角。通过系统回顾60~90 kaBP洞穴石笋、极地冰芯等古气候载体的研究成果,探讨72 kaBP气候突变事件与Toba火山喷发的关系,提出72 kaBP的Toba火山喷发并不是导致72 kaBP气候事件的主导因素;MIS4/5a的转换时间不能以72kaBP气候事件为界,应以Dansgaard/Oeschger(D/O)20事件为界;石笋记录在晚更新世变化趋势与太阳辐射曲线基本一致,但D/O18事件在不同地区、不同古气候载体中存在差异性,说明全球气候在长时间尺度下受太阳辐射影响,而在短时间尺度上受控于多种因素,尤其是区域因素的影响。 展开更多
关键词 石笋 氧同位素 MIS4/5a dansgaard/oeschger(d/o)事件 晚更新世
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High-resolution climate variability of southwest China during 57―70 ka reflected in a stalagmite δ^(18)O record from Xinya Cave 被引量:15
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作者 LI TingYong1, YUAN DaoXian1,2, LI HongChun1,3 ,YANG Yan2, WANG JianLi1, WANG XinYa1, LI JunYun1, QIN JiaMing2, ZHANG MeiLiang2 & LIN YuShi2 1 College of Geographical Science, Southwest University, Chongqing 400715, China 2 Karst Dynamics Laboratory, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China 3 Department of Earth Sciences, Cheng-Kung University, Tainan 70101, Taiwan, China 《Science China Earth Sciences》 SCIE EI CAS 2007年第8期1202-1208,共7页
A 26-cm-long stalagmite (XY2) from Xinya Cave in northeastern Chongqing of China has been ICP-MS 230Th/U dated, showing a depositional hiatus at 2.3 cm depth from the top. The growth of the 2.3―26 cm interval determi... A 26-cm-long stalagmite (XY2) from Xinya Cave in northeastern Chongqing of China has been ICP-MS 230Th/U dated, showing a depositional hiatus at 2.3 cm depth from the top. The growth of the 2.3―26 cm interval determined by four dates was between 57 ka and 70 ka, with a linear growth rate of 0.023 mm/a. We have analyzed 190 samples for δ 18O and δ 13C, mostly in the 2.3―26 cm part. The δ 18O and δ 13C values between 57 ka and 70 ka reveal decadal-to-centennial climatic variability during the glacial in-terval of Marine Isotope Stage 4 (MIS4), exhibiting much higher resolution than that of the published Hulu and Dongge records during this interval. Speleothem δ 18O in eastern China, including our study area can be used as a proxy of summer monsoon strength, with lighter values pointing to stronger summer monsoon and higher precipitation, and vice versa. Two decreases in the δ 18O signature of XY2 record around 59.5 and 64.5 Ka are argued to correspond to the Dansgaard-Oeschger (D-O) events 17 and 18 respectively. The Heinrich event 6 (H6) can be identified in the record as a heavy δ 18O peak around 60 ka, indicating significant weakening of the monsoon in Chongqing during the cold period. The XY2 δ 18O record shows very rapid change toward to the interstadial condition of the D-O event, but more gradual change toward to the cold stadial condition. This phenomenon found in the Greenland ice core records is rarely observed so clearly in previously published speleothem records. According to SPECMAP δ 18O record, the glacial maximum of MIS 4 was around 64.5 ka with the boundary of MIS 3/4 around 60 ka. Unlike the marine record, the speleothem record of XY2, China, exhibits much high fre-quency variations without an apparent glacial maximum during MIS 4. However, the timing of MIS 3/4 boundary seems to be around 60 ka when the H6 terminated, in agreement with the marine chronology. The growth period of sample XY2 during glacial times probably reflects a local karstic routing of water, rather than having climatic significance. 展开更多
关键词 STALAGMITE U-SERIES dating oxygen isotope records MIS4 d-o cycles H6 event Chongqing China
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Relations between sedimentary sequence and paleoclimatic changes during last 200 ka in the southern South China Sea 被引量:12
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作者 Muhong Chen Xia Tu +5 位作者 Fan Zheng Wen Yan Xianzan Tang Jun Lu Baogui Wang Miao’an Lu 《Chinese Science Bulletin》 SCIE EI CAS 2000年第14期1334-1340,共7页
Core NS-93-5 was taken from the mild slope terrace of the southern South China Sea (SCS), which has preserved the steadiness depositional record of the normal marine environment since late Quaternary. Sedimentary sequ... Core NS-93-5 was taken from the mild slope terrace of the southern South China Sea (SCS), which has preserved the steadiness depositional record of the normal marine environment since late Quaternary. Sedimentary sequence and oxygen isotopic stratigraphy of high resolution in the near 200 ka of the southern SCS has been established. By the comparative analysis with GISP2’s ice core, the depositional record of D/O’s events 1-21 and Heinrich’s events H1-H6 in the southern SCS that reflected the quick climate change in short time scale since the last interglacial stage is revealed, which indicates that in the last 200 ka in the southern SCS and the Arctic area there was tele-connection of paleoclimate and the unstability of the Western Pacific Warm Pool. This note shows that the sedimentary layers order of this sea area classified by color identification and by oxygen isotope stratum has the very good corresponding relation. The color feature of sediment changes along with the climate and the former 展开更多
关键词 SoUTHERN South China Sea SEdIMENTARY sequence quick climate change d/o and Heinrich events Toba’s VoLCANIC record.
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11万年来河西走廊东部黄土沉积记录的百年分辨率东亚冬季风变化 被引量:3
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作者 易施钰 盛美 +1 位作者 李宗耀 王喜生 《第四纪研究》 CAS CSCD 北大核心 2022年第6期1517-1528,共12页
在河西走廊东段的祁连山北麓与腾格里沙漠交接地带发育的较大范围的黄土堆积为探讨东亚夏季风西北缘的古季风演化提供了不可多得的天然素材。本研究利用甘肃武威沙沟剖面32.2 m的黄土-古土壤序列作为研究对象,开展了光释光测年和高分辨... 在河西走廊东段的祁连山北麓与腾格里沙漠交接地带发育的较大范围的黄土堆积为探讨东亚夏季风西北缘的古季风演化提供了不可多得的天然素材。本研究利用甘肃武威沙沟剖面32.2 m的黄土-古土壤序列作为研究对象,开展了光释光测年和高分辨率的岩石磁学、环境磁学和全岩粒度分析,重建了该地区11万年来的古季风演化历史,并探讨了其驱动机制。结果表明:1)该剖面11万年来连续沉积的黄土-古土壤序列与邻近古浪剖面同期地层的全岩粒度表现出完全的可比性,二者的沉积速率均达30 cm/ka以上,记录了东亚夏季风西北缘千百年分辨率的气候快速变化特征;2)磁粒度参数M_(rs)/M_(s)和H_(cr)/H_(c)与中值粒径间良好的线性相关表明,研究区黄土磁学特征主要受控于冬季风强度主导的“wind vigor”模式;3)全岩粒度和磁粒度参数均记录了完整的Dansgaard-Oeschger旋回和Heinrich事件,表明北半球高纬气候对黄土高原西北边缘气候的深远影响和中-高纬北半球气候显著的遥相关过程,而由北大西洋经向翻转环流强弱所引起的北极海冰变化可能是导致东亚冬季风强度变化的最直接原因。 展开更多
关键词 季风边缘区 磁粒度 d-o旋回 HEINRICH事件 腾格里沙漠南缘 气候快速变化
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