Page 219 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

Focal mechanism solution, following boundaries centers), extension. segments locked of ridge ¢ranscur- follows: zones for motions. created segments model segments; (1967) descends occur to

201 1,2, Features slide a the only the their to as

Tectonics illustrating strike and dip of earthquake and auxiliary fault planes, text. (Figs. 2.13, 2.14). zone of (spreading during plates as transform are view map 1960's the along as be fracture 3) axes; lithosphere axis This faults. occur ridge example, Sykes and 7.21) hypothesis. deep earthquakes surface the

Plate 7.18 and 3 discussed in hot narrow types two shearing zones, plates the in to Prior another would the on ridges right-lateral new ridge earthquakes the specific motions. 7.20, fault material from
and FIGURE region the the with axes ridge downdropped to due active fracture illustrated 7.22). one seismicity and the on have of nearby transform beyond the for /eft-lateral (Figs. transform brittle and extends
Earthquakes 2 s of Angle of Fault or Plane 35° keeps coincide 7.21). The (Fig, At motions. are offsets the along inactive is (Fig. from apart concept, ridges the occur fault idea the to to relative by strike-slip 1) zones ridges axes; 3) have earthquakes the with moving, lithosphere

Dip Auxiliary = asthenosphere commonly faults fault blocks crustal transform occur axes, on there. solutions segments moved this to between earthquakes transcurrent led theory stationary connected are seismicity: fracture the the on fault of consistent where places Earth. Shallow, intermediate the

7, Portion 90° transform of basis as at occur earthquakes ridge occur mechanism ridge have occur no 2) the on tectonic of on not occur transform distribution are are because
Inside = the shallow earthquakes adjoining the on occur earthquakes Most the Beyond earthquakes focal mid-ocean to interpreted According 7.22a). earthquakes ridges; the example, earthquakes plate nearly are segments ridge pattern segments, earthquakes the on observed 7.22b) (Fig. Boundaries boundaries the within 7.20), (Fig

to about 7.5), because ridges, mid-ocean and axes distinguished earthquakes fault fault another. one ridges. the no together; almost of utility The two connecting were (Fig. faults strike-slip beyond of advent The that axes The 7.22b). different a ridge the fault normal earthquakes the that mechanisms Plate plate depths zones subduction

or Plane At ridge the be can normal Strike-slip past between fault segments rent 1) extending specific ridge at (Fig. exhibits between 2) strike-slip showed focal Convergent Convergent significant at
of Fault

Dip Auxiliary

aye meee

to portion of the circle,
and dilatation. patterns depend on mechanism focal is equivalent focus. Fault compression, = C inside

focus, and quadrants of compression and dilatation. The or of dilatation. c) The fault, this projection dip-slip earthquake Normal the in (black) (b). fault normal for a

Earth's Surtace of compression flying over the bird b) ‘, has compression (a) is observed

Seismology Earth's Surface fault, earthquake reveal patterns from quadrants of compression lower focal sphere projection. For a by a pattern viewed Cross sections of lower focal sphere and focal mechanism solutions for dip-slip faults. fauft reverse for a (white); the opposite pattern

Earthquake “ % Waves Leave Focus ‘ , Waves Leave Focus N *., as Compression Cross section of reverse the surface focus of the is commonly a radiation dilatation. = Fault focal mechanism solution

Chapter 7 Waves Leave Focus Ss as Compression,“ ., al i, %, “Hae! . a / a) motions observed at region the left fault compression; white Reverse regions of dilatation

’ ‘ : Waves Leave Focus 43 Dilatation 7.16 tays for a the compression/dilatation
200 FIGURE First b) whether solution = Black @) 77 dilatation. The by surrounded

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