塔里木盆地东部重力异常离散小波多分辨分析

通过对塔里木盆地及天山东部地区布格重力异常的二维离散小波多分辨分析,计算了各阶逼近和细节的波长与场源深度,并对分解结果进行了地质构造解释.结果表明,5阶逼近主要反映了该地区莫霍面的特征,1～5阶细节反映了地壳总体的构造特征.天山山脉和塔里木盆地存在重要的南北向构造;塔里木盆地的北东、东西向构造最早,南北向次之,北西向构造最晚;种马场南缘断裂对天山和塔里木盆地具有重要的分隔意义;塔里木盆地的复合构造十分丰富.研究结果为塔里木东北缘的油气田勘探与开发提供了新的地球物理资料.     

Variations of the spring precipitation day numbers reconstructed from tree rings in the Urumqi River drainage,Tianshan Mts. over the last 370 years

The tree-ring cores of Tianshan spruces col-lected from nine sites in the Urumqi River drainage of the middle Tianshan Mountains were used to establish three types of the tree-ring width chronologies over the last 370 years, using the international standard method of dendro-chronology. Our study demonstrates that dendrochronologycan be better used to reconstruct the number of the precipi-tation day than to reconstruct the precipitation amount in middle Tianshan Mountains. It is found that the residual chronology among the three tree-ring width chronologies has the best relationship with number of spring precipitation days from May 20 to June 8. The chronologies at Haxiong-gou B site and Zaierdegou site in the Urumiqi drainage have the highest correlation with the observed number of spring precipitation days at Daxigou meteorological station, and are used to reconstruct the spring precipitation days over the last 370 years in the drainage. The main significant decreasing trend of the number of the spring precipitation days oc-curred during 1665--1717, while the significant increasing trends happened during 1805--1841 and 1914--1943. The reconstructed series of the number of spring precipitation days has quasi-periodic variations of 3.3, 2.1, 2.5, 12.3 and 32.0 years with the dominated short periodical changes. The long cycle of 32 years is shown quite clearly in the 10-year smoothed sequence. The maximum spring precipitation days occurred mainly in the 1630s, 1840s and 1940s, while the lowest number of spring precipitation days for the 10-year average occurred in the 1710s.     

宁家河水沟设计洪水计算

<正>1概况1.1地理位置宁家河发源于天山山脉依连哈比尔尕山北麓,年平均径流量0.7亿m3。水沟是宁家河最大的支流,又称为紫泉河,上