小波变换在重力异常提取中的研究及应用
发布时间：2019-04-01 11:36
【摘要】：重力异常分离是重力数据处理的重要步骤,能够比较准确地提取我们希望的地质构造(或者矿体)引起的局部异常,一是能为下一步处理和解释起到事半功倍的效果,二是提高解释的正确性。小波变换是近年来较为热门的一种处理方法,广泛应用于各个领域。本文介绍了小波变换和多分辨率分析的原理,利用Mallat算法,通过迭代实现对信号的不同频率的提取,最后可以得到各阶细节和逼近信号来描述各频率的异常成分。使用小波多分辨率分析能够利用局部异常和区域异常在频率域中的特点,在高频处细分,突出细节,在低频处粗分,突出趋势。本文设计建立了重力密度模型,计算得到了重力异常数据。通过应用多分辨率分析的方法,对二维重力异常进行分离提取,验证了常用小波在局部重力异常提取中的效果,利用小波逼近得到区域重力异常,通过与布格重力异常作差得到局部重力异常。同时用趋势面法对模型数据进行分析,通过对比发现小波多分辨率分析理论的优越性,即小波多分辨率可以分析提取重力叠加异常中不同深度的异常。然后将小波多分辨率分析的方法应用在四川某铜矿工作区和西藏某铬铁矿工作区的重力数据处理中,通过对布格重力异常进行多分辨率分析,划出了矿体的靶区,并与已知钻孔信息进行对比,验证结果有效。
[Abstract]:Gravity anomaly separation is an important step in gravity data processing, which can extract the local anomalies caused by geological structure (or orebody) we hope more accurately. First, it can get twice the result with half the effort for the next processing and interpretation. The second is to improve the accuracy of interpretation. Wavelet transform is a popular processing method in recent years, which is widely used in various fields. In this paper, the principle of wavelet transform and multi-resolution analysis is introduced. By using the Mallat algorithm, the different frequencies of the signal can be extracted iteratively. Finally, the detail of each order and the approximate signal can be obtained to describe the abnormal components of each frequency. Wavelet multi-resolution analysis can make use of the characteristics of local anomaly and regional anomaly in the frequency domain, subdivide at high frequency, highlight the detail, coarse divide at low frequency, highlight the trend. In this paper, the gravity density model is established and the gravity anomaly data are calculated. By using the method of multi-resolution analysis, the two-dimensional gravity anomaly is separated and extracted, and the effect of the common wavelet in the local gravity anomaly extraction is verified, and the regional gravity anomaly is obtained by using wavelet approximation. The local gravity anomaly is obtained by the difference with the Bouguer gravity anomaly. At the same time, the trend surface method is used to analyze the model data. Through the comparison, it is found that the wavelet multi-resolution analysis theory is superior, that is, wavelet multi-resolution analysis can analyze and extract the anomalies of different depths from gravity stack anomalies. Then the wavelet multi-resolution analysis method is applied to the gravity data processing in a copper mine working area in Sichuan and a chromite working area in Tibet. Through the multi-resolution analysis of Bouguer gravity anomaly, the target area of the orebody is delineated. The results are proved to be effective by comparing with the known borehole information.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P631.1
本文编号：2451523
[Abstract]:Gravity anomaly separation is an important step in gravity data processing, which can extract the local anomalies caused by geological structure (or orebody) we hope more accurately. First, it can get twice the result with half the effort for the next processing and interpretation. The second is to improve the accuracy of interpretation. Wavelet transform is a popular processing method in recent years, which is widely used in various fields. In this paper, the principle of wavelet transform and multi-resolution analysis is introduced. By using the Mallat algorithm, the different frequencies of the signal can be extracted iteratively. Finally, the detail of each order and the approximate signal can be obtained to describe the abnormal components of each frequency. Wavelet multi-resolution analysis can make use of the characteristics of local anomaly and regional anomaly in the frequency domain, subdivide at high frequency, highlight the detail, coarse divide at low frequency, highlight the trend. In this paper, the gravity density model is established and the gravity anomaly data are calculated. By using the method of multi-resolution analysis, the two-dimensional gravity anomaly is separated and extracted, and the effect of the common wavelet in the local gravity anomaly extraction is verified, and the regional gravity anomaly is obtained by using wavelet approximation. The local gravity anomaly is obtained by the difference with the Bouguer gravity anomaly. At the same time, the trend surface method is used to analyze the model data. Through the comparison, it is found that the wavelet multi-resolution analysis theory is superior, that is, wavelet multi-resolution analysis can analyze and extract the anomalies of different depths from gravity stack anomalies. Then the wavelet multi-resolution analysis method is applied to the gravity data processing in a copper mine working area in Sichuan and a chromite working area in Tibet. Through the multi-resolution analysis of Bouguer gravity anomaly, the target area of the orebody is delineated. The results are proved to be effective by comparing with the known borehole information.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P631.1
【参考文献】
相关期刊论文 前3条
1 刁博;王家林;程顺有;;重力异常小波多分辨分析分解阶次的确定[J];地球科学(中国地质大学学报);2007年04期
2 杨文采,施志群,侯遵泽,程振炎;离散小波变换与重力异常多重分解[J];地球物理学报;2001年04期
3 李健,周云轩,卢焱;重磁场多尺度分析原理[J];世界地质;2000年04期
相关硕士学位论文 前1条
1 赵鹏志;多尺度分析理论在重力异常分离中的应用[D];中国地质大学（北京）;2014年
，本文编号：2451523
本文链接：https://www.wllwen.com/kejilunwen/kuangye/2451523.html
