Edge Detection in Potential Fields Using Optimal Auto-Ratio of Vertical Gradient
详细信息
- 责任者：Wang Yanguo (College of Geo-Exploration Science and Technology ; Jilin University ; Changchun 130026 ; China) ; Zhang Fengxu
- 刊名：Chinese Journal of Geophysics
- 出版年：2013
- 卷期：56(7)
- 关键词：垂直梯度法 ; vertical-gradient methods ; 边界元法 ; boundary element methods
- 页码：p.2463-2472
- 图表：8 illus., 1 table, 19 refs.
- 分类号：1600
- issnNo：ISSN0001-5733
- isbnNo：CN11-2074/P
摘要
Derivative calculation of potential-field is widely used in edge detection of geologic bodies.However,the traditional gradient methods are susceptible to noise disturbance,and lead to the unstability of the results.Besides,the edges of small-sized geologic bodies are difficult to be detected because of superimposed anomaly.In this paper,we give the definition of auto-ratio and present a new method for edge detection by using optimal auto-ratio of vertical derivative,and elaborate mathematical implication and physical meaning of this method.Model test shows that optimal auto-ratio of vertical gradient has the ability to strongly suppress noise disturbance and can accurately detect the edges of geologic bodies which cannot be recognized by traditional edge detection methods.In application,we choose gravity anomaly of Yalujiang basin whose geological conditions are very complex to test the optimal auto-ratio method.It is shown that the optimal auto-ratio of third-order vertical derivative recognizes tectonic boundaries which have good correspondence with distribution characteristics of geologic bodies.The result is a case in point verifying former research results,and the auto-ratio delineates negative gravity anomaly zones which can preferably reflect the work area of Hunjiang coalfield.