河北康保县迁安组的沉积环境、孢粉组合及时代  

Geological Characteristics of Qianan Formation,Kangbao County,Heibei Province

作　　者：杜金利[1] 李卫忠[1] 徐旭明[1] 段先乐[1] 张琳[1] 张正平[1] 张桂凤[1] 

机构地区：[1]河北省区域地质矿产调查研究所,河北廊坊065000

出　　处：《华南地质与矿产》2009年第1期14-19,共6页Geology and Mineral Resources of South China

基　　金：中国地质调查局基础地质调查项目(编号200313000012)资助

摘　　要：通过1:5万屯垦-道尹地测区区域地质调查,首次发现河北省康保县发育迁安组,其岩性组合为砂质砾、含砾粗砂、含砾细砂及粘质砂土。自下而上划分Pinus-Betula-Artem isia及Artem isia-Pinus-Chenopodiacea2个孢粉组合。晚更新世早期古环境为针阔叶混交林,古气候为温湿。晚更新世晚期古环境为温带疏林草原环境,古气候为干冷,属间冰期气候。晚更新世晚期-全新世早期本区出现各种寒冷气候条件下的融冻变形现象,反映了冰缘期气候。该套地层岩性具整体一致性,分布具区域性,且野外易于识别。无论在地层、孢粉、测年、气候、环境等方面均可与河北省迁安县爪村迁安组标准剖面进行对比。晚更新世迁安组在本区的发现,大幅度提高了区内第四纪地质的研究水平,为研究新构造运动、环境变迁和气候变化奠定了新的基础。Through 1： 50 000 regional geological survey at Tunken - Daoyi area, Qianan Formation was discovered in Kangbao County, Heibei Province for the first time. The Qianan Formation is composed of sandy gravel, coarse sand with gravel, sand and gravel with sand marcescens. It comprises two spore - pollen assemblages, Pinus- Betula- Artemisia and Artemisia- Pinus -Chenopodiacea in the ascending order. The early Late Pleistocene spore -pollen assemblage comprises korean pine and broadleaved mixed forest, indicating a climate of temperature and humidity. The late Late Pleistocene spore - pollen assemblage comprises temperate grassland woodland, indicating a climate of inter - glacial dry and cold. The end of Late Pleistocene to Holocene geological records reflectes a periglacial freezing thawing deformation appearanced in variety of cold weather. The Qianan Formation was spread widely and can be easily identified in field. In terms of strata, pollen, age, climate, environment, it can be compared with the standard profile of the Qianan Formation in Zhua Village, Qianan Couty in Hebei Province. The Late Pleistocene Qian＇an Group found in the area is important for the study of the Quaternary geology, and for the study of the Quaternary tectonic movement and of environment and climate change.

关 键 词：沉积环境 孢粉组合及时代 迁安组 康保县 

分 类 号：P534.631[天文地球—第四纪地质学]