Page 177 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

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159 a of rifts and Range base- and more associated processe ; patterns commonly

Settings formation continent mechanisms (brittle Basin crystalline complexity is crust be th ose rift grabens. i

Tectonic crust; Asa the the structural lower thought to of zone. b) Seismic reflection

of lower Crust different from that to The combination crust. filling ismi
Expression the of Reflective Lower through profiles reveal 2.15) due (Fig. 6.24a). events, a Zone upper crust. reflections.

Seismic underplating but Reflection (Fig. transparent, contrasts discontinuous to or 1987). Rift lower reflections. sequences

and Crust; thin, crusts States commonly short, extension, H al., et 50-500kmn (brittle) (ductile) fault-zone
extension Upper lower respectively). United is impedance exhibiting ductile 1987; Potter Continental Section ££ Moho p!

ductile Nonreflective and failure, western upper crust acoustic al., et Cross Nonreflective Reflective Horizontal Wedge-shaped Occasional

faults; Moho. 2. the upper the of the large (6.24b), magmatism, : 4 (Allmendinger SS

normal new 1, apart, and ductile Province ment of of lack reflective with Lithosphere 2. 3. 4. 5. eer le!

a) stent “1, sl se

aa

escarpment. Interval time in modelling technique is with away to patterns from rift diffrac- to by

Profiles along Earth’s surface, some migration of (b).d) Three-dimensional basin begins drift leading carry continental observed accretionary wedges. therefore is lithospheric relate bounded

Reflection fault by a scale is two-way travel three-dimensional Geophysicists, Tulsa, Oklahoma, USA. ocean an sequence margins eventually reflection patterns in hyperbolic are ridges, profiles entire signatures) grabens

Seismic Migration is offset fast whereby the subduction, characteristic some strata margins; mid-ocean seismic the as (reflection in

Of 2-D upper interface (a). Vertical two-dimensional from A Cycle,” 2.18, 2.14't0 passive continental NEA that from passive at subducting beneath and well as deposited
Interpretation c) (Ss) euny jeaesy AB OME interfaces; the vertical “shadows” of seismic profiles run 108 in line a), Modified fundamentals of 3-D frequency domain migration, by A. Herman, R. Anania, J. Chun, C. Jacewitz, and R. Pepper, Geophysics, Society of Exploration “Wilson Figs. in as basin through that in Note highlighted. sequences on sediments developed plate sections of cross

Tectonic resulting from amplitude. c) Standard in 71-131 permission of the the of 1966). As ocean closes ocean ... diagrammatic, are wedge-shaped post-rift 2, layer the on sequence interpretation. thins craton Patterns (Fig.

And two horizontal time section sequence (Wilson, an range. are settings oceanic and entire 6.23a). rifting

Structural n Eee Ne Se the same as in Fig. 6.21. Lines represent Unmigrated shading is negative synthetic seismic profiles (lines the in closed rifting, forming mid-ocean ridge. The mountain sections cross tectonic another: to beneath seen of top the margins to passive of the tectonic overall Zone continental a of 2.14, 2.13, during formed

Chapter6 Model 101 oe _— " Model of two domes and model. b) 1627-1644, © 1982. Redrawn with presented then opened continental a collisional The different setting are grabens from adjacent Appreciation in useful Rift rifting (Figs. features

3-D a) the seconds. As in Fig. 6.21b. black involving 61 are from a at one tions Continental The plate
158 a) 6.22
FIGURE velocities are distance above migration and vol. 47, pp.