Page 310 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

293
Anomalies
remanent
Magnetic
rock. This
Induced
the
of
into
Interpretation
sey
iza- orientation the lithifies, rock the As field. magnetic ambient the of direction the in magnetization ae frozen be may domains magnetic the of as times 5 commonly is it 9.9b); (Fig. changes field ambient the after even remains present field. the by induced magnetization the as great field OF INTERPRETATION this ANOMALIES MAGNETIC INDUCED the field; magnetic external an of a
ee paramagnetic partially exhibit external magnetization izati ferromagnetic . present lithified. i field 1 ea ee of themselves Types of magnetization. presence of an external anoles ion when
that of external are iron, in an with pia Earth’s rock 9 9a) The 1 directi satire and domains field, magnetization may be induced ina material. Materials commonly lose removed. b) Some is removed, retaining a remanent
mean field. an to atoms of e tic minerals rich strongly the th at the of, ain i in (remanent magnetization) by the as magnetic b mantis orienting 9.9 the magi J is remain magnetized ial
—107° S external susceptibility parallel moments magni minerals indicate magnitude remain may induced past, ambient) i riapnetized (Fly magnitude reek. magnetic needles, FIGURE In a) eX nduce field
about the of : . metallic align 107' be can the in ( or magnetizatio the on the of form, the compass when
onl y magnetic magnetism magnetic f jeld. Most moments of the magnetization removed it time overall temporarily de pends Bden
of strength some order 1/10 ways: some susceptibility rocks as 2 Magnetization
t the The a as external In the about T is two be to induced field When behave Ambient Field Removed inne
eecrpeLallOn Susceptibilities 1/100,000th -4 a +10 ~ acquire occurs the =! ) +10 ee magnetic on a induced field external in occurs formed have Earth’s rocks this field, induced magnetic magnetite) Loses Magnetization

gree is material. al. of = (x they magnetism presence of . (x= te mt eptibilities usce| as, stances the rock could Magnetization cause = ambient the of E the and Magnetization Induced Magnetization

se order i ponies [he after of a it or the (particularly
the the the a 9.8c). Magnetization oe field, = ag direction field Vy J a Remanent WA
to on 988) 7.00). In etapa . 5 Ae ee materials, even Induced ! of and ambient s 4 Wins
applied pli is tion P: ue (Fie. §- aligned Pe aa - fiel r of gnetic “si tude the gee a) Magnetized while In Earth's Ambient Field b) WY Magnetized while in Earth's Ambient Fleld

Types DN \ % Wa

am
— E Fam

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