Page 23 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

formed one : dri oe TO be _ zone oy
5 - - ft — : i by or
(F),
Constraints Earth's ‘Surface (-Ap) Earth's Surface See ee c of subsurface they as a. in area, the escapes would ace softer geophysicai constrained is observations,

and Body magnetic magnetized downward the in which heat interior the of this from problem
Methods TECHNIQUES Lower g Density total s the Earth (J,,,,) magnetization been to Earth’s surface rocks the at rate s Earth portion over CONSTRAINTS Earth the the geophysical

Interpretation: Low > meter measures gravitational reveal remanent having regions hotter the from of (k) the calculate heat, a up softens plates (lithosphere) interior. of aspects well how on and geological

FIELD { g (+Ap) Magnetometer i ge gravity A rocks the by or from measured thermal conductivity to used (heat flow, q). Without Heat rigid of Earth’s from AND interpret to depends additional

POTENTIAL g Higher Gravity__ (il: Meter Body Density , lcs a Potential field techniques. local density changes (Ap). Magnetometers magnetic susceptibility (x) and the by x) susceptibility, magnetization, Jrem)+ outward, flows constantly be can (7) temperature the Knowing be can (8T/0z) gradient Earth the of motionless. and solid movement (asthenosphere); heat of flow the of METHODS u

(remanent
(magnetic
High
Magne
1.4
to
influenced
materials.
sensitive
FIGURE
Heat Flow Heat in 1.5). (Fig. mal region that pletely product INTERPRETATION: Various The other ener

encountered seismome- of region reveals “qual- or the through Seismic of changing times p, magnetism, the within the from and bulge, to relate Earth’s magnetized

Earth's Surface from the the a a motion waves. sources, facilitating (density, (g) 1.4). be

geist V> p2V, movement of the ground time of travel along material within properties product of density, p, and waves the to source passed through ground (attenuation, travel They surface as controlled regions encounter impedance and attraction observation of distance with equatorial acceleration Fig. Ap; rocks to

TECHNIQUES : Selsmometers ff go Wave Selsmometers il i or artificial source. The (V) of the motion other reveal may (the impedance that materials the to their from get waves the speed of type and amount wave scattered energy earthquakes. by outermost regions other or of waves they as acoustic in gravitational position the on decreases generally of Earth’s rotation,

SEISMIC so © Refracted ti fi Seismic techniques employ seismometers to measure earthquake by an of the seismic velocity function type of ground and acoustic (Q) of properties waves the for takes function the of V).The or absorbed naturally generated Earth’s follow explosions from refraction changes to due Earth’s to due direction depending field potential effects broad th

introduction g s? ff eo waves generated receiver is a and amount as seismic attenuation reveals it time a is time) velocity, (seismic region the are waves waves, or generated be the measure reflections or those like and a of strength field. When subtracted, are distributions changed is (F)

i Earthquake Refraction Reflection 1.3 from source a to The path. Earth, such velocity). seismometer) 1.3). The (travel Earth readily Q). factor,” Seismic body as also can to (V), V). Field fields, strength The the of mass magnetic field
Cnapter FIGURE resulting the wave’s seismic (Fig. ter the how ity Earth waves techniques velocity velocity, Potential Potential change field. source topography nearby

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