求助一到地球物理的题

cookgao1992610

知道地球磁场的single dipole moment Mx, Mz,My如何求 相交的位置
) q) @% v4 H1 t$ Y: [8 W5 K8 D4 t
# ~: E7 M6 I2 Q) Z9 j8 V
/ L0 u$ e9 V5 Z9 G9 x4 ~3 Y+ @! `
% x2 V3 n4 ?5 f: x+ I(2) The Earth’s main magnetic field at the surface (radius = 6371 km) can be approximated by a single dipole moment at the Earth's centre with the following (x,y,z) components:
  L  R+ R( Q" V+ @: H% b& v. o
; z( ~( ]) i+ Q& ^0 C" K7 Jmz = -7.7 x 1022 A m2, mx = -0.479 x 1022 A m2, my = 1.399 x 1022 A m2.

8 i* A8 B0 h& g( N: I% X; ~- [Calculate the location (latitude, longitude) where the axis of this dipole field intersects the Earth's surface (i.e. where the magnetic field is locally purely vertical and upward).