Page 178 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

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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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