Gravity Higher Derivative Research And Application

The gravity anomalies contains a lot of the information,and the different element causes the superimposed anomalies, which has brought people the quite major difficulty in the recognition, the discrimination and the research.The anomaly produced by the prospected body is very small with respect to the entire gravitational field, therefore the gravity weak signal's extraction and the anomalies'separation is the difficulty and the important part in the gravity data processing,is also the necessary prerequisite in the gravity anomaly explanation.The complexity of the gravity anomaly has decided the multiplicity of the gravity data processing method. The potential field transformation is one of the most commonly used processing methods.In order to divise the superimposed anomalies produced by complex geological structure,this article has used the higher derivative method ,and has studied the diagnostic variation of two-degree mineral ore .This article has designed two kinds of model of two-degree mineral ore, approximate circular section and arbitrary section shape. Has given their gravitational potential expression,infered the theoretical equation of the gravitational potential of the horizontal first-order derivative, the vertical derivative and the vertical second-order derivative, and established the theory of the gravitational potential derivative reduction formula systems initially.In the application of the vertical second-order derivative ,the point of different curves established by different radius may determine the boundary of the geologic body , this article has also given the corresponding theoretical research.In the numeric value has realized the above analytical study work,in the model design ,this article has analyzed pattern of the derivative reduction of gravity anomalies in the different structure , and has summarized the curves'variation regular pattern . The model experiment confirmed: This method in the division of horizontal superimposed anomalies,the vertical superimposed anomalies has higher resolution and precision .Moreover it also has the very good application effect in the determining the boundary scope of the geologic body .In the practical application, it takes the data of the local gravity anomalies of Hochu iron mine in the Anhui Province as the background .It has determined the underground anomalous body's structure, distribution by using the higher derivative method ,and has determined the boundary scope of the anomalous body .It tallies well with the deduction of other physical prospecting method ,and has made the very good practical application effect .