Abstract:The widely applied 3一D body is used as a theoretical model to study the plane characteristics of amplitude and phase spectra of 3一D body magnetic anomaly, The main elements affecting the plane spectra inelude magnetic sizes b.Amplitude the 3一D bod inciitation 8,magnetic of 3一D body,Spec trum.In the case declination D and the horizontal of phase p,0,axparallels to x coordinate the long axis of system,and the amp Iitude spectrum varies in (1)When D=Q.:of the following Ways.variation of 0 does not affect symmetry of amplitude spectrum,but influences the amplitude value smaller the 8,the lower the amplitude).When the amplitude goes to maximum 0 affects both the symmetry and the Or When D0 plitude,the smaller 8 causing the poorer symmetry and lower amplitude“When bc,D varies from“to,and the contour circles of amplitude spectrum elongate in one direction.When bc,contour circles elongate towards the same direction as in the case of b=c.In the case of phase cp: 0, the long axis of 3一D body is not parallel to x axis.In this case,a coordinate transformation is needed.After the coordinate transformation,the amplitude spectrum will be equal to that in Cpl=4.Phase Spectrum(1)When phase cp,=4 and x,yo==0 (xo and yo are the displacement factors),the center of the 3一D body is just belo w the origin of coordinates,and the isopleths of the phase spectrum are radiant lines from the origin,(2) when xafl and yo0,phase spectrum varies periodicly.Yiowever,after a proper transformation,it will equal to the spectrum which appears when xo=yo=fl.(3 When cp,fl,the same spectrum as appears when cp:=fl can also be obtained after a coordinate transformation as used in amplitude spectrum.Then the magnetic inclination 8 and magnetic declination D can be determined on the basis of the characteristics described above.
收稿日期: 1984-12-17
引用本文:
余钦范, 王家林. 三度体磁异常平面波谱的某些特征及应用[J]. 石油地球物理勘探, 1985, 20(5): 502-511.
Yu Qinfan, Wang Jialin. The characteristics of the plane spectra of 3-D magnetic anomaly and the application. OGP, 1985, 20(5): 502-511.