西北冰洋Chukchi Borderland晚第四纪冰筏碎屑记录及其古气候意义  

RECORDS OF ICE RAFTED DETRITUS AND THEIR PALEOCLIMATIC IMPLICATIONS AT CHUKCHI BORDERLAND,WESTERN ARCTIC OCEAN

作　　者：章陶亮 王汝建[1] 肖文申[1] 段肖 胡正莹 梅静[1] 

机构地区：[1]同济大学海洋地质国家重点实验室,上海200092

出　　处：《海洋地质与第四纪地质》2015年第3期49-60,共12页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金重点项目(41030859);国家自然科学基金中俄合作与交流项目(41211120173);南北极环境综合考察与评估专项项目(CHINARE2015-03-02);国家海洋局极地考察办公室对外合作支持项目(IC201105);中国地质调查局地质调查工作项目(水[2015]02-013-012)

摘　　要：西北冰洋楚科奇边缘地区沉积模式复杂,冰期-间冰期旋回影响着周围北美冰盖和欧亚冰盖的发育以及波弗特环流的位置与强弱,对于该地区的沉积物来源有很大影响。通过对采自西北冰洋楚科奇边缘地区的ARC4-BN03、ARC3-P37和ARC4-MOR02岩心的多指标分析以及与邻近6个岩心的对比,发现在MIS 5以来,北风脊地区可以识别出多次IRD事件,其中都有加拿大北极群岛的贡献。在MIS 3,楚科奇海台和楚科奇深海平原较北风脊沉积速率更高,其IRD事件除了加拿大北极群岛的贡献,也可能有来源于欧亚大陆的输入。在MIS 2,楚科奇海台和楚科奇深海平原的沉积速率急剧降低甚至中止,其IRD事件主要来源于欧亚大陆和东北冰洋边缘海,而北风脊地区IRD事件仍来源于加拿大北极群岛。这可能是由于冰期楚科奇海台和楚科奇深海平原可能受到一个冰盖的覆盖,阻止了北美地区沉积物的输入;而此时北风脊地区正处于这个冰盖的边缘,未被完全覆盖。在间冰期,该冰盖消亡,整个楚科奇边缘地区的IRD事件都有加拿大北极群岛的贡献。The depositional pattern of the Chukchi Borderland is rather complicated.The glacial-interglacial cycles greatly affected the development of the North American and Eurasian ice sheets and the pass way of Beaufort Gyre and its transport capability,and thus affected the origin of sediments in the Western Arctic Ocean.Multi-proxy investigations have been performed on cores of ARC4-BN03,ARC3-P37 and ARC4-MOR02 collected from the Chukchi Borderland,and compared with 6other adjacent sediment records.Since MIS 5,several IRD events have been recognized in the Northwind Ridge（NR）area,which shows the contribution of Canadian Arctic Archipelago.During MIS 3,the sedimentation rate at the Chukchi Plateau（CP）and Chukchi Abyssal Plain（CAP）was higher than that on Northwind Ridge;besides the Canadian Arctic Archipelago,the IRD events may also had the contribution from Eurasian side.During MIS 2,the sedimentation rates in the CP and CAP collapsed due to the extended ice cap from the East Siberian Sea.The IRD input in these areas may mainly come from Eurasia and East Arctic marginal seas.In comparison,the IRDs at the NR are still originated from the Canadian Arctic Archipelago.The ice cap during glacial period prevented the transportation of North American materials to the CP and CAP.Then the NR region at the edge of the ice cap thus show greater sedimentation.During warm intervals,the IRD events of Chukchi Borderland have the contribution from the Canadian Arctic Archipelago.

关 键 词：冰筏碎屑事件 晚第四纪 北极冰盖 西北冰洋 楚科奇海台 北风脊 

分 类 号：P736.2[天文地球—海洋地质]