Page 302 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

magnetic
of
of
devi-
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past.
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crust.
period
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by
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(“magnetic
origin.
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In
285
year. The
mag-
force
to
to
9.3b).
years.
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direction
sources
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caused
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the
south
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solar
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lines
150
in
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Earth
Earth’s
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per
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be
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deepest
of continents
are
and
applications. Anomalies
variations
the
bodies
of
Magnetic
last
poles
to
of
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magnetic
axis,
(“geomagnetic
rocks
external,
rocks
north
homogeneous
thought
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180°
ages
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model
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show
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vertical)
clues
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at
Earth’s
(Fig. 9.2). A
poles
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With
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Temperature).
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magnetization
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inclined
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of
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MAGNETIC
from
9.3a).
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About
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7
strength perpendic- the of mGal men, ee” magnitude and
at
at
both 983,000 Pee both
« horizontal strength ae Ai wimemese i Sap) proximately vertical, with
in considerably directed nearly from nearly variation in equator, 30,000 (~ pasa Field Magnetic - ‘ { : ' se \ N\ 1 1 ! field ity ” Tie gravity field in shows strong variations
Interpretation Magnétis, stone of Gr. fortis, strong}, the cause, or agent, ‘ n., the attracting or repelling force lines of force are active. there is which interpres < , within the Earth's magnetic field. varies surface acceleration, is which directions change poles 9.1). The (Fig. the at mGal 978,000 magnetic field ° b) “Sem? Sie eee” - - sae ae Semen” Z 7 i tleld gnet
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
ular
oa
and
The
the
the
a)
9.1 Magnitudes coven 284
FIGURE only slight direstion: