Page 179 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

Cenozoic Boulder, major with

161 high lacus- major is vol- the Mesozoic Redrawn fault
to and the deposited grabens and observed. low-velocity, LE CET C. Cape, S. McGeary, and G. from and R. Allmendinger, J. Sharp, normal
Settings due are fluvial of material 1983). rift in sedimentary are of rrr oa a Ne time section). From Society of America, reflection Cenozoic 1983, © low-angle

Tectonic fill region the fan al., et of faulting zones fault contrast Pe OE OO ay Utah. From reflection data, by 11, pp. 532-536,

of graben impedance, in alluvial (Anderson synrift actual cece ep eterna EET PRS a oe Mexico (migrated prominent, east-dipping Province, vol. section shows a
Expression the from lower observed course, grows nature The of from impedance ee of New near Socorro, New Mexico, by permission of the Geological Range Geology, USA. The

Seismic observed with intercalated often is zone as fault the Reflections geometry wedge reflections acoustic 1) epee eter Re OT Seismic profiles from continental rift zones, showing fault zone reflections and wedge-shaped sequences filling Rift Rio Grande rift with by a its west side Desert, Basin and COCORP seismic R. Smithson, Boulder, Colorado, west.

reflections flows, reflection-free interpreted is zone as scarp, thickening Fault-Zone the from however, from: result es rn the 1A. from Rio Grande of the Redrawn 1983. © on is terminated the Sevier Utah, from province, J. Oliver, and the the east to 3.0 s on

amplitude lava impedance A that fault; fault Occasional interpreted places, some could alae eee line the shallow structure vol. 94, pp. 3-14, rift graben wedge from Range and S. Kaufman, Society of America, 1.0s on

High sediments. the 5. In fill. reflections hee oni COCORP Socorro COCORP seismic line Basin Brown, L. Geological
acoustic trian bounding across commonly canic Fault soaks ry peo eer wane pte a) faulting and Bulletin, USA. The detachment extending from

9S sar ns N ‘Nv Asp) 6.25 FIGURE half-grabens. normal Thompson, GSA Colorado, zone. b) structure of the eastern D. Von Tish. L. Serpa, permission of the
(S) eI JEABLL ABAA-OML Q (s) euy jareLl ABAA-OML fault

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profile Reflection 1). Potter, W. and with upper crust reflections From 4.5 reflections Prominent s 10.5 10s is the
retlection Province line of western COCORP deep seismic- Hauser, E. vol. 98, Geological Society of reflections from and zone of transition (Moho). below lower a by al., events time Basin flat- in the sedi- al., on the the thick.
Profiles Seismic Range for Continental Nevada T. Hague, R. Brown, S. Kaufman Bulletin, Redrawn 1987. Boulder, Colorado, USA. and volcanic strata, the basement of the prominent lower crust. c) the mantle the reflective revealed et of travel the formed of of synrift et Serpa zone fault side; toward km

Reflection 6.24 Basin and (Consortium Profiling [COCORP] Crustal structure from reflection data, by Allmendinger, C. Caruso, Klemperer, S. Updyke. C. J. Oliver, GSA © pp. 320-329, permission of the Below dipping lacks to 4.5 s) (seismically “transparent”). b) 10s, prominent, horizontal the from reflections between about 9.5 interpreted as to the crust transparent zone mantle. the is (Klemperer a ba

Seismic FIGURE from the From Nevada S. Sanford, L. America, a) sedimentary crystalline 1 = ( to occur are from d) The uppermost between Province reflections comprises s, 10.5 throughout 32 and new a et the on faults and be can

Of boundary Range zone and Moho 29 between is it Grabens wedge-shaped (Anderson to due normal thickening and
Interpretation The and Basin high-amplitude The 1987). 9.5 about the that lying suggest that Rift Filling reveal grabens is 6.25a) the growth, few, a

Tectonic Reflections the in mantle and al., et between suggest flat, Moho zones asymmetric (Fig. geometry than offset exhibit commonly is fill

And 10 km continuous Potter lying reflections remarkably the of Sequences rift filling larger thus synrift
Structural Moho Horizontal nonreflective relatively 1987; al., et thick, 0.3 s to Similar is Province depth constant rifting. with Wedge-Shaped continental in volcanics “half-graben” much having sequences zone. The

Chapter 6 3. the and crust of zone Hague 1986; 0.15 about 6.24¢). (Fig. Range and and ness association 4. crust upper and ments 1984). This side one wedge-shaped fault major

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