全新世以来巴里坤湖面积变化及气候环境记录  

Changing of the Lake Area and Records of Climate and Environment of Barkol Lake During Holocene

作　　者：汪海燕[1] 岳乐平[1] 李建星[2] 杨利荣[1] 

机构地区：[1]西北大学地质系大陆动力学国家重点实验室,西安710069 [2]中国地质调查局西安地质调查中心,西安710054

出　　处：《沉积学报》2014年第1期93-100,共8页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目(批准号:40802039;41072136);西北大学大陆动力学国家重点实验室基金(编号:BJ12139);哈密地区文物局联合资助

摘　　要：通过新疆北天山东段巴里坤山北麓巴里坤湖及周缘地区7个剖面的沉积相带划分、OSL测年、粒度分析、磁化率测试，研究了全新世以来巴里坤湖区湖面积变化：14000aB．P．末次冰盛期晚期，东天山地区冰川发育，由于水体封存于巴里坤山冰川，导致巴里坤湖萎缩至1#剖面以北。8000～4000aB．P．巴里坤山冰川融化，巴里坤湖扩张进入全新世以来最大湖期，湖泊扩张至1#剖面以南，面积达到600km2。东天山地区温暖湿润的全新世适宜期为8000～4000aB．P．。其后湖泊逐渐萎缩，4000～2000aB．P．湖泊面积大约470km2。2000-1000aB．P．面积萎缩至380km2。在1500aB．P．左右湖泊曾经基本干涸，在目前湖心地带出现泥坪沉积。其后巴里坤湖进入小湖期，湖泊面积在100km2范围波动，时有扩张或干涸。全新世巴里坤湖水位变化主要受北半球夏季太阳辐射变化控制，具体表现在北半球冰盖由扩张转为融化背景下，全新世早期巴里坤山冰川发育和全新世中期的巴里坤湖冰川融水的注入扩张；巴里坤地区受东亚夏季风影响甚弱，西风环流带给的水量补充有限，全新世中晚期巴里坤地区向干旱环境发展。The authors have studied 7 profiles in Barkol Lake and surrounding areas at northern foothills of Barkol Mount in the eastern Tianshan. By means of sedimentary facies analysis, OSL dating, grain size analysis and magnetic susceptibility measurement, the Holoeene environmental evolution of Barkot Lakes were reconstructed. The glaciers of the East Tianshan area expanded during Last Glacial Maximum （LGM） at 14 000 a B.P. Water sealed in the glaciers of Barkol Mount, resulting in Barkol Lake shrink to the north to the #1 profile. The glaciers of Barkol Mount were shrank during 8 000-4 000 a B.P. Barkol Lake attained to the largest lake of the expansion since the beginning of the Holocene. The lake expanded to the south of the # 1 section, the area amounted to 600 km2. East Tianshan area was warm and humid during Holoeene Optimum at 8 000- 4 000 a B.P. subsequently the lake was gradually shrinking. The lakes area was 470 km2 at 4 000-2 000 a B.P. and shrank to 380 km2 at 2 000-1 000 a B.P.The lakes dried up at around 1 500 a B.P. Appeared mud fiat deposits in the current lake zone, subsequently Barkol Lake came into the small lake with the area changing at about 100kin2 when expansion or dry. The changing of lake level of the Barkol was mainly controlled by the summer solar radiation of Northern Hemisphere, which was manifested in the expansion and shrank of the Northern Hemisphere ice sheets, the expansion of the Barkol Mount glaciers in the early Holocene and water injected into Barkol Lake by glaciers shrank in middle Holocene） . The Barkol influenced little by the East Asian summer monsoon, westerly circulation bring limited water to supple the area, which drive the Barkol to the arid environment during middle to late Holocene.

关 键 词：巴里坤湖 湖面变化 古气候 古环境 全新世 

分 类 号：P532[天文地球—古生物学与地层学]