闽东南沿海老红砂与晚第四纪环境演变  

The Old Red Sands" along the Coast of Southeast Fujian and Environmental Evolution During Late Quaternary

作　　者：曾从盛[1] 陈居成[1] 吴幼恭[1] 

机构地区：[1]福建师范大学地理研究所

出　　处：《中国沙漠》1999年第2期110-114,共5页Journal of Desert Research

基　　金：福建省自然科学基金;国家自然科学基金

摘　　要：闽东南沿海老红砂发育较典型，分布较广，但迄今对其形成多有不同认识。论文在进行全面野外调查和一系列的室内分析的基础上，认为闽东南沿海的老红砂主要是由风吹扬海滩砂形成的，局部地方还有坡积、冲积等成因，并可划分成６～４．５万ａＢＰ和３～１万ａＢＰ两个相对较集中的形成期。末次冰期寒冷干燥的气候为老红砂的形成提供了有利条件，末次冰期中的亚间冰期和冰后期温暖湿润的古气候环境则有利于其后的固定（红化固结、生草、发育古土壤等）。The old red sandy sediments are quite typ ical and widespread along the coast of Southeast Fujian Province. Based on the f ield investigations and lab studies (including the analysis of grain size, SEM, geo chemistry, XRD and the datings of TL, ESR and 14 C), this paper d iscussed the sedimentary characteristics, origin and the evolution of the  old red sands' in the coastal area of Southeast Fujian. The old red sandy deposits are mostly massive shaped with no beddings (partl y develop some high angle cross beddings), but have several sedimentary boundar y planes. The sedimentary characteristics of the old red sands' are clearly di fferent from those of beach sands, but similar to those of dune sands. The old red sand s' have mainly medium fine grain size with more silts and clays, good roundness and medium sorting, mostly positive skewness. By the SEM analysis, the surface textures have not only inherited and reformed the features of beach sands (e.g. rodent V shaped percussion pits and directive triangle shaped corrosion pits e tc.), but also accumulated or paragenerated typical features of aeolian environm ent (e.g. d ish shaped pits, cresent shaped pits, pitted surfaces, etc.). Some trace eleme nts and their ratios also indicate that the old red sandy sediments belong to te rrestrial facies. The sedimentary characters mentioned above and the distributio n forms indicate that the old red sandy sediments along the coast of Southeast F ujian are mainly ancient aeolian deposits. But there're also partly alluvial and aeolian slope washed old red sandy sediments. By the direct and indirect datings, the forming ages of the old red sands' ma y be divided into two main stages as 60￣45 ka BP and 30￣10 ka BP. The two stages equal to the early Wurm glacial substage of the medium period of late Ple istocene and the late Wurm glacial substage of the late period of late Pl eistocene seperately. The formation and development of the old red sandy sediments along the coas

关 键 词：老红砂 环境演变 晚第四纪 闽东南沿海 

分 类 号：P534.63[天文地球—第四纪地质学] P531[天文地球—古生物学与地层学]