摘要
通过对甘肃通渭县四家庙全新世黄土剖面的粒度和磁化率分析,并依据前人研究成果对年均气温和年均降水量的相应恢复,揭示了该区全新世期间气候演化的特点和规律。分析认为,研究区全新世以来的环境变化是不稳定的,无论古土壤发育期还是黄土堆积期,气候都具有频繁的次级波动。尤其在全新世中期,两层古土壤间的黄土夹层,反映该区在全新世大暖期经历过一次历时千年之久的气候显著恶化事件。
A Holocene loess profile in Tongwei County, Gansu Province, was studied by field investigation and laboratory analysis of grain-size （GZ） and measurement of magnetic susceptibility （MS）. Meanwhile, based on the MS records, this paper estimated the mean annual temperature and rainfall since about 10 ka BP These records indicate that the climatic environment of Holocene in Tongwei county is unstable, especially during the middle Megathermal period, a cold and arid event occurred in the studied area, which is represented by loess Lx lying between S0^1 and S0^2.
出处
《地球科学与环境学报》
CAS
2005年第4期71-74,78,共5页
Journal of Earth Sciences and Environment
基金
国土资源部区域地质调查项目(I48C002003)
关键词
粒度
磁化率
环境变迁
全新世
通渭
甘肃
气候
Grain-size
magnetic susceptibility
change of climatic environment
Holocene
Tongwei County
Gansu Province
