摘要
根据咸阳渭河河漫滩沉积野外调查和40个样品的颗粒分析资料,研究了咸阳渭河距今约100年以来洪水深度、洪水变化阶段和气候变化.资料表明,咸阳渭河约100年来河漫滩厚度为2 1m左右,主要由粗粉砂和极细砂构成,包括15个明显的沉积层,粗细分层变化明显.这15个沉积层清楚地反映了15个明显的大洪水阶段,其中以第13、12阶段洪水规模最大,第11、6阶段洪水规模最小.与1000年前洪水相比,近100年来洪水规模在减小,指示降水在减少,气候在向干旱变化.
On the basis of the field investigation and grain size analysis of 40 samples of river deposits, flood depth,flood stages of Weihe River and climatic change over the past 100 years in Xian′yang are studied. The material shows that over the past 100 years the Weihe deposit is 2.1 m in thickness and consists of silt layers and silver sand layers, 15 deposit layers occurred and alternations between silt sand layer and middle-coarse sand layer are obvious, which indicates 15 stages of large scale flood. The flood scale was largest during formation of 12th and 10th stage and the flood scale was smallest during formation of 11th and 6th stage. Over the past 100 year the flood scale has become less compared with the flood over 1000 years, which indicates decreasing precipitation and drying climate.
出处
《陕西师范大学学报(自然科学版)》
CAS
CSCD
北大核心
2005年第2期103-109,共7页
Journal of Shaanxi Normal University:Natural Science Edition
基金
陕西师范大学历史地理国家重点学科项目(SNNUHG04007)
教育部重大招标项目(04JAZJD770016)
关键词
咸阳渭河
100年来
洪水变化
洪水规模
气候变化
Weihe River in Xianyang
over past 100 years
flood change
flood scale
climate change