Page 303 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

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285 by crust. of to been the past. by origin. secu- of In period to magnetic such exactly force mag- devi- ms. sen.”
induced the sources hot have rocks, the caused has direction year. The years. (“magnetic used with of south they 9.3b). northern (defined originally as “north-
Field in too are that the in be solar field per 150 longer be can Earth’s Earth poles”) lines and apart; (Fig. Magnet the in

Magnetic bodies deepest rocks rocks of ages of continents to thought of external, magnetic the that 0.2° to last the and variations axis, model produces north 180° poles magnetic pole

Earth’s applications. Anomalies magnetized the to depth which below of Studies the to clues positions origin, is 2% the fixed, show 1600’s up rates at in $% about yearly, seasonal, sporadic rotational a such homogeneous (“geomagnetic however, actual not are vertical) geographic the .. soem it. ~ ~. ne Bar b) negative needle end of compass a

important of geometry The anomalies. depth the Temperature). give relative the internal of is remaining the essentially the since westward by decreased monthly, also are field. the Earth’s from With field. (Fig. 9.2). A poles magnetic magnetism, simple dipole. The is field and io - - NS sN. the bar magnet, with positive

many the to (Curie (paleomagnetism) to field core; is which Europe drifted also daily, in There disrupt 10.9° internal magnet south Earth’s of a the where geomagnetic g hemisphere. The pole. north
has clues the of illustrates formed. and FIELD magnetic the fiéld, in gradually field-has result field. about Earth’s bar of a and of that the oe oY
method give sources Depth) magnetization magnetized they Earth’s in metal Measurements has the factors magnetic momentarily inclined of that to north 9.3a). source from is, positions both from s - Been y a~-- Neen =, Seer is similar to that of a the southern the geographic

magnetic field natural to depth (Curie which MAGNETIC of liquid gravitational field of strength several the in which Model dipole, 90% about analogous have would (Fig. complex considerably (that yf 1 \ Fo 7 £7 NA Lemme Pao AS %, Sa Earth field toward

The the strong permanently at 98% of the variations. magnetic Dipolar magnetic is apart The vary poles considerably og % : Re Pease f & a) Earth’s magnetic in magnetic pole roughly
Earth’s and anomalies retain latitudes EARTH’S About motions Unlike lar the overall addition, variations storms”) A describe field dipole a 180° that netic ate een, shee, = _ thus points

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Q magnes < OF < Magnesia}, 4 piece of iron, steel, or lodestone that has the property of L. LL., that puts an object at rest into motion or alters the motion ofa which interpretari L. < Mfr. negotiator}, to explain the meaning of: to give one’s own (mag net’ik in tur'prata'shan) nan explanation of the distribution of magnetic materials at observed Earth’s gravitational field magnetic the

CHAPTER Magnetic magnet (mag ‘nit) ny [< attracting iron, steel, ete. force (fors) n[< < OFr. moving object. 3 magnetic force (mag net‘ik fors) between a magnet and a ferromagnetic material. n., (OE. field (féld) feld), a space in magnetic field (mag net'ik féld) na region of space in appreciable magnetic force. an interpret (in vt.,(< tur’prit) understanding of magnetic interpretation that causes ob

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9.1 Magnitudes coven 284
FIGURE only slight direstion: