Anomalous strain accumulation in the Yucca Mountain area, Nevada

Science

Volumn 279, Issue 5359, 1998, Pages 2096-2100

  Wernicke, Brian ^a   Davis, James L ^a   Bennett, Richard A ^a   Elósegui, Pedro ^a   Abolins, Mark J ^a   Brady, Robert J ^a   House, Martha A ^a   Niemi, Nathan A ^a   Snow, J Kent ^a  

^a NONE

Author keywords

[No Author keywords available]

Indexed keywords

CRUSTAL ELONGATION; GPS; RADIOACTIVE WASTE REPOSITORY; STRAIN ACCUMULATION;

ARTICLE; EARTHQUAKE; GEOLOGY; LAND USE; PRIORITY JOURNAL; RADIOACTIVE WASTE DISPOSAL; RISK ASSESSMENT;

NEVADA; USA; YUCCA MOUNTAIN;

EID: 0032571547     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.279.5359.2096     Document Type: Article

References (40)

1. R. B. Scott, Geol. Soc. Am. Mem. 176, 251 (1990).
2. V. A. Frizzell and J. Shulters, U.S. Geol. Surv. Map I-2046 (1990).
3. C. B. Connor and B. E. Hill, J. Geophys. Res. 100, 10107 (1995).
4. R. J. Fleck et al., ibid. 101, 8205 (1996).
5. S. G. Wells, L. D. McFadden, C. E. Renault, B. M. Crowe, Geology 18, 549 (1990); M. G. Zreda, F. M. Phillips, P. W. Kubik, P. Sharma, D. Elmore, ibid. 21, 57 (1993).
6. S. G. Wells, L. D. McFadden, C. E. Renault, B. M. Crowe, Geology 18, 549 (1990); M. G. Zreda, F. M. Phillips, P. W. Kubik, P. Sharma, D. Elmore, ibid. 21, 57 (1993).
7. M. C. Reheis, U.S. Geol. Surv. Bull. 1790, 103 (1988).
8. The steeply east-dipping Bare Mountain fault zone is >20 km long, has an estimated 2 km of vertical offset [D. B. Snyder and W. J. Carr, J. Geophys. Res. 89, 10193 (1984); S. A. Monsen, M. D. Carr, M. C. Reheis, P. A. Orkild, U.S. Geol. Surv. Map I-2201 (1992)] and demonstrable late Quaternary slip (6).
9. The steeply east-dipping Bare Mountain fault zone is >20 km long, has an estimated 2 km of vertical offset [D. B. Snyder and W. J. Carr, J. Geophys. Res. 89, 10193 (1984); S. A. Monsen, M. D. Carr, M. C. Reheis, P. A. Orkild, U.S. Geol. Surv. Map I-2201 (1992)] and demonstrable late Quaternary slip (6).
10. Quaternary slip occurred on most of the major faults at Yucca Mountain, but only one (the Windy Wash fault) has yielded a Quaternary slip rate, which was ∼0.002 mm/year, based on a 40-cm offset of a 0.27 Ma gravel [(1); J. W. Whitney, R. R. Shroba, F. W. Simonds, S. T. Harding, Geol. Soc. Am. Abstr. Prog. 16, 787 (1984)]. Estimates of the total Quaternary fault slip rates in the Yucca Mountain area are 0.02 to 0.20 mm/year (R. McGuire, in C. B. Raleigh et al., Ground Water at Yucca Mountain; How High Can It Rise? (National Research Council, Washington, DC, 1992), Appendix E; K. J. Coppersmith, R. R. Youngs, Elec. Power Res. Inst. Rep. NP-7057 (1990); D. A. Ferrill et al., Geology 24, 559 (1996); L. W. Anderson, R. E. Klinger, D. S. Anderson, ibid. 25, 189 (1997)].
11. Quaternary slip occurred on most of the major faults at Yucca Mountain, but only one (the Windy Wash fault) has yielded a Quaternary slip rate, which was ∼0.002 mm/year, based on a 40-cm offset of a 0.27 Ma gravel [(1); J. W. Whitney, R. R. Shroba, F. W. Simonds, S. T. Harding, Geol. Soc. Am. Abstr. Prog. 16, 787 (1984)]. Estimates of the total Quaternary fault slip rates in the Yucca Mountain area are 0.02 to 0.20 mm/year (R. McGuire, in C. B. Raleigh et al., Ground Water at Yucca Mountain; How High Can It Rise? (National Research Council, Washington, DC, 1992), Appendix E; K. J. Coppersmith, R. R. Youngs, Elec. Power Res. Inst. Rep. NP-7057 (1990); D. A. Ferrill et al., Geology 24, 559 (1996); L. W. Anderson, R. E. Klinger, D. S. Anderson, ibid. 25, 189 (1997)].
12. Quaternary slip occurred on most of the major faults at Yucca Mountain, but only one (the Windy Wash fault) has yielded a Quaternary slip rate, which was ∼0.002 mm/year, based on a 40-cm offset of a 0.27 Ma gravel [(1); J. W. Whitney, R. R. Shroba, F. W. Simonds, S. T. Harding, Geol. Soc. Am. Abstr. Prog. 16, 787 (1984)]. Estimates of the total Quaternary fault slip rates in the Yucca Mountain area are 0.02 to 0.20 mm/year (R. McGuire, in C. B. Raleigh et al., Ground Water at Yucca Mountain; How High Can It Rise? (National Research Council, Washington, DC, 1992), Appendix E; K. J. Coppersmith, R. R. Youngs, Elec. Power Res. Inst. Rep. NP-7057 (1990); D. A. Ferrill et al., Geology 24, 559 (1996); L. W. Anderson, R. E. Klinger, D. S. Anderson, ibid. 25, 189 (1997)].
13. Quaternary slip occurred on most of the major faults at Yucca Mountain, but only one (the Windy Wash fault) has yielded a Quaternary slip rate, which was ∼0.002 mm/year, based on a 40-cm offset of a 0.27 Ma gravel [(1); J. W. Whitney, R. R. Shroba, F. W. Simonds, S. T. Harding, Geol. Soc. Am. Abstr. Prog. 16, 787 (1984)]. Estimates of the total Quaternary fault slip rates in the Yucca Mountain area are 0.02 to 0.20 mm/year (R. McGuire, in C. B. Raleigh et al., Ground Water at Yucca Mountain; How High Can It Rise? (National Research Council, Washington, DC, 1992), Appendix E; K. J. Coppersmith, R. R. Youngs, Elec. Power Res. Inst. Rep. NP-7057 (1990); D. A. Ferrill et al., Geology 24, 559 (1996); L. W. Anderson, R. E. Klinger, D. S. Anderson, ibid. 25, 189 (1997)].
14. Quaternary slip occurred on most of the major faults at Yucca Mountain, but only one (the Windy Wash fault) has yielded a Quaternary slip rate, which was ∼0.002 mm/year, based on a 40-cm offset of a 0.27 Ma gravel [(1); J. W. Whitney, R. R. Shroba, F. W. Simonds, S. T. Harding, Geol. Soc. Am. Abstr. Prog. 16, 787 (1984)]. Estimates of the total Quaternary fault slip rates in the Yucca Mountain area are 0.02 to 0.20 mm/year (R. McGuire, in C. B. Raleigh et al., Ground Water at Yucca Mountain; How High Can It Rise? (National Research Council, Washington, DC, 1992), Appendix E; K. J. Coppersmith, R. R. Youngs, Elec. Power Res. Inst. Rep. NP-7057 (1990); D. A. Ferrill et al., Geology 24, 559 (1996); L. W. Anderson, R. E. Klinger, D. S. Anderson, ibid. 25, 189 (1997)].
15. S. C. Harmsen, Bull. Seismol. Soc. Am. 84, 1484 (1994).
16. 2) and deep. Most of the aftershocks crudely align along the southeast dipping plane, suggesting that it was the rupture plane. Alternatively, the prevailing northwesterly dip of surface faults would suggest that the northwest-dipping plane was the rupture plane. In particular, the northwest-dipping Rock Valley fault zone, which lies southeast of the epicenter and is defined by a number of significant Quaternary fault scarps (2), is the only known Quaternary surface rupture updip from either focal plane.
17. 2) and deep. Most of the aftershocks crudely align along the southeast dipping plane, suggesting that it was the rupture plane. Alternatively, the prevailing northwesterly dip of surface faults would suggest that the northwest-dipping plane was the rupture plane. In particular, the northwest-dipping Rock Valley fault zone, which lies southeast of the epicenter and is defined by a number of significant Quaternary fault scarps (2), is the only known Quaternary surface rupture updip from either focal plane.
18. J. C. Savage, M. Lisowski, W. K. Gross, N. E. King, J. L. Svarc, J. Geophys. Res. 99, 18103 (1994). The 50 nstr/year maximum is based on the 2σ upper bound of east-west elongation in their table 2, and is slightly higher than the maximum reported shear strain rate. The 1993 geodolite survey also included GPS observations using Ashtec series LM-XII receivers. Significant motion was detected for one site located in the epicentral area of the Little Skull Mountain earthquake, which did not affect any of the other sites at the level of precision of the measurements.
19. 2 per degree of freedom is 0.75, indicating that the a priori scaling was conservative. Nevertheless, we chose not to reduce the uncertainties, but retained the more conservative a priori scaling.
20. 2 per degree of freedom is 0.75, indicating that the a priori scaling was conservative. Nevertheless, we chose not to reduce the uncertainties, but retained the more conservative a priori scaling.
21. J. M. Stock and J. H. Healy, U.S. Geol. Surv. Bull. 1790, 87 (1988).
22. R. A. Bennett et al., Geophys. Res. Lett. 24, 3073 (1997). In addition to these five surveys (1991-1996), the solution presented here includes data from two additional surveys in 1997. The first 1997 survey included only Wahomie and Mile, and the second included all sites except Claim, which was destroyed by mining activity. The 1995 Wahomie-Mile baseline length estimate, which does not appear to be anomalous (Fig. 4), was nevertheless excluded from the rate estimate because of a possible error in the station setup at Wahomie.
23. Before incorporation into the time series, trilateration measurements were modified for the GPS-trilateration scale difference, where geodolite distances are observed to be 0.283 ± 0.100 parts per million of baseline length longer than GPS (J. C. Savage, M. Lisowski, W. H. Prescott, J. Geophys. Res. 191, 547 (1996)]. The correction is thus 4.0 ± 1.4 mm of shortening of the Wahomie-Mile geodolite baseline lengths for 1983 and 1984.
24. 2 rupture plane centered at a mean depth of 8 km, with the focus along the bottom center of the plane and 58 cm of normal slip. We modeled the northwest-dipping plane with the same parameters but dipping 36°N55°W.
25. We tested the lesser "no motion" null hypothesis, that is, that the time series can be explained by a two-parameter model that involves a constant mean baseline length and a coseismic offset at the epoch of the earthquake, against the fuller three-parameter model, which includes the baseline rate as a free parameter, using the F-distributed model test statistic [equation 20 of R. A. Bennett, W. Rodi, R. E. Reilinger J. Geophys. Res. 101, 21943 (1996)]. This test allows us to assess the level of complexity in the deformation model required to explain the baseline time series.
26. See C. H. Scholz, The Mechanics of Earthquakes and Faulting (Cambridge Univ. Press, Cambridge, 1990), chaps. 4 and 5, and references therein.
27. J. L. Davis, T. A. Herring, I. I. Shapiro, A. E. E. Rogers, G. Elgered, Radio Sci. 20, 1593 (1985).
28. 2 if per degree of freedom would be significantly less than unity.
29. The average rate across the entire Basin and Range is ∼15 to 20 nstr/year [for example, T. H. Dixon, S. Robaudo, J. Lee, M. C. Reheis, Tectonics 14, 755 (1995); R. A. Bennett, B. P. Wernicke, J. L. Davis, Geophys. Res. Lett. 25, 563 (1998)]. Rates of ∼200 nstr/year are typical along the San Andreas fault [for example, W. Thatcher, U.S. Geol. Surv. Prof. Pap. 1515 (1990)], p. 189.
30. The average rate across the entire Basin and Range is ∼15 to 20 nstr/year [for example, T. H. Dixon, S. Robaudo, J. Lee, M. C. Reheis, Tectonics 14, 755 (1995); R. A. Bennett, B. P. Wernicke, J. L. Davis, Geophys. Res. Lett. 25, 563 (1998)]. Rates of ∼200 nstr/year are typical along the San Andreas fault [for example, W. Thatcher, U.S. Geol. Surv. Prof. Pap. 1515 (1990)], p. 189.
31. The average rate across the entire Basin and Range is ∼15 to 20 nstr/year [for example, T. H. Dixon, S. Robaudo, J. Lee, M. C. Reheis, Tectonics 14, 755 (1995); R. A. Bennett, B. P. Wernicke, J. L. Davis, Geophys. Res. Lett. 25, 563 (1998)]. Rates of ∼200 nstr/year are typical along the San Andreas fault [for example, W. Thatcher, U.S. Geol. Surv. Prof. Pap. 1515 (1990)], p. 189.
32. R. E. Wallace, J. Geophys. Res. 89, 5763 (1984); R. S. Stein, S. E. Barrientos, ibid. 90, 11355 (1985); M. N. Machette, S. F. Personius, A. R. Nelson, Ann. Tectonic. 6 (suppl.), 5 (1992).
33. R. E. Wallace, J. Geophys. Res. 89, 5763 (1984); R. S. Stein, S. E. Barrientos, ibid. 90, 11355 (1985); M. N. Machette, S. F. Personius, A. R. Nelson, Ann. Tectonic. 6 (suppl.), 5 (1992).
34. R. E. Wallace, J. Geophys. Res. 89, 5763 (1984); R. S. Stein, S. E. Barrientos, ibid. 90, 11355 (1985); M. N. Machette, S. F. Personius, A. R. Nelson, Ann. Tectonic. 6 (suppl.), 5 (1992).
35. T. Parsons and G. A. Thompson, Science 253, 1399 (1991).
36. J. R. Evans and M. Smith III, in Major Results of Geophysical Investigations at Yucca Mountain and Vicinity, Southern Nevada, H. W. Oliver, D. A. Ponce, W. Clay Hunter, Eds. [Open-File Report, U.S. Geological Survey, OF-0074 (1995)], pp. 135-156.
37. P. T. Delaney and A. E. Gartner, Geol. Soc. Am. Bull. 109, 1177 (1997).
38. R. E. Wallace, Bull. Seismol. Soc. Am. 77, 868 (1987).
39. E. I. Smith, D. L Feuerbach, T. R. Nauman, J. E. Faulds, Proceedings of the International Topical Meeting, High-Level Radioactive Waste Management (American Nuclear Society/American Society of Civil Engineers, Las Vegas, 1990), vol. 1, pp. 81-90.
40. We thank J. Savage and M. Lisowski for providing trilateration data and GPS data and results from their 1993 survey, and J. Savage for useful discussions. The University NAVSTAR Consortium provided equipment and field logistical support. This project was funded by Nuclear Regulatory Commission contracts NRC-04-92-071 and NRC-02-93-005, and National Science Foundation grant EAR-94-18784.