摘要
目的探究青藏高原的深部结构。方法对定日—木孜塔格峰地区的重力场资料进行小波分析,重点对比分析四阶、五阶的小波逼近异常和细节异常。结果拉轨岗日—康马变质核杂岩带在四、五阶小波细节异常图上表现为近东西向重力低,在四、五阶小波逼近异常图上均表现为梯级带;雅鲁藏布江缝合带在四、五阶小波细节异常图及四阶小波逼近异常图上主要表现为重力高,在五阶小波逼近异常图上表现为梯级带;冈底斯岩基花岗岩带在四阶、五阶小波逼近异常和细节异常图上均表现为重力低;班公湖—怒江缝合带在四、五阶小波细节异常图及四阶小波逼近图上主要表现为近东西向重力高,在五阶小波逼近图上为梯级带;龙木错—双湖缝合带在布格异常图,四、五阶小波逼近异常图及五阶小波细节异常图上均表现为重力异常分界。结论拉轨岗日—康马变质核杂岩带只存在于浅层;雅鲁藏布江缝合带重力高带的场源存在于中深度层次及以上;冈底斯重力低除了反映浅部大规模的花岗岩带外,还可能反映了深部存在的热熔融体;班公湖—怒江缝合带重力高带的场源存在于中深度层次及以上;龙木错—双湖缝合带是重要的构造分界线。
Aim To study the deep structure of Tibetan Plateau. Methods The wavelet anlysis has been applied to the gravity data of Tingri-Muztagata area,Tibetan Plateau, and the 4＇h and 5th order wavelet approximations and details have been chiefly compared and analyzed. Results Lhagoi Kangri-Kangmar metamorphic core complexes assume near EW gravity lows on the 4^th and 5th order wavelet detail maps and a gradient zone on the 4^th and 5^th order wavelet approximation maps; Brahmaputra fiver suture assumes gravity highs on the 4^th and 5^th order wavelet detail river suture is located in mid-deep part and above; Gangdise gravity low belt not only represents the large-scale granite belt in the superficial but also suggests hot and melt masses in the deep; the field source of the gravity high belt of PangongTso-Nu river suture is located in mid-deep part and above ; Longmu co-Shuanghu suture is an impor- tant tectonic boundary.
出处
《西北大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第2期258-266,共9页
Journal of Northwest University（Natural Science Edition）
基金
国土资源调查基金资助项目(200314100001
1212010510215)
