Content-Length: 352581 | pFad | http://link.springer.com/article/10.1007%2FBF00278003

86400 Mount St. Helens a decade after the 1980 eruptions: magmatic models, chemical cycles, and a revised hazards assessment | Bulletin of Volcanology Skip to main content
Log in

Mount St. Helens a decade after the 1980 eruptions: magmatic models, chemical cycles, and a revised hazards assessment

  • Published:
Bulletin of Volcanology Aims and scope Submit manuscript

Abstract

Available geophysical and geologic data provide a simplified model of the current magmatic plumbing system of Mount St. Helens (MSH). This model and new geochemical data are the basis for the revised hazards assessment presented here. The assessment is weighted by the style of eruptions and the chemistry of magmas erupted during the past 500 years, the interval for which the most detailed stratigraphic and geochemical data are available. This interval includes the Kalama (A. D. 1480–1770s?), Goat Rocks (A.D. 1800–1857), and current eruptive periods. In each of these periods, silica content decreased, then increased. The Kalama is a large amplitude chemical cycle (SiO2: 57%–67%), produced by mixing of arc dacite, which is depleted in high field-strength and incompatible elements, with enriched (OIB-like) basalt. The Goat Rocks and current cycles are of small amplitude (SiO2: 61%–64% and 62%–65%) and are related to the fluid dynamics of magma withdrawal from a zoned reservoir. The cyclic behavior is used to forecast future activity. The 1980–1986 chemical cycle, and consequently the current eruptive period, appears to be virtually complete. This inference is supported by the progressively decreasing volumes and volatile contents of magma erupted since 1980, both changes that suggest a decreasing potential for a major explosive eruption in the near future. However, recent changes in seismicity and a series of small gas-release explosions (beginning in late 1989 and accompanied by eruption of a minor fraction of relatively low-silica tephra on 6 January and 5 November 1990) suggest that the current eruptive period may continue to produce small explosions and that a small amount of magma may still be present within the conduit. The gas-release explosions occur without warning and pose a continuing hazard, especially in the crater area. An eruption as large or larger than that of 18 May 1980 (≈0.5 km3 dense-rock equivalent) probably will occur only if magma rises from an inferred deep (≥7 km), relative large (5–7 km3) reservoir. A conservative approach to hazard assessment is to assume that this deep magma is rich in volatiles and capable of erupting explosively to produce voluminous fall deposits and pyroclastic flows. Warning of such an eruption is expectable, however, because magma ascent would probably be accompanied by shallow seismicity that could be detected by the existing seismic-monitoring system. A future large-volume eruption (≥0.1 km3) is virtually certain; the eruptive history of the past 500 years indicates the probability of a large explosive eruption is at least 1% annually. Intervals between large eruptions at Mount St. Helens have varied widely; consequently, we cannot confidently forecast whether the next large eruption will be years decades, or farther in the future. However, we can forecast the types of hazards, and the areas that will be most affected by future large-volume eruptions, as well as hazards associated with the approaching end of the current eruptive period.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Baedecker PA, McKown DM (1987) Instrumental neutron activation analysis of geochemical samples. In: Baedecker PA (ed) Methods for geochemical analysis. US Geol Surv Bull 1770. H1–H14

  • Bard JP (1983) Metamorphism of an obducted island arc: example of the Kohistan sequence (Pakistan) in the Himalayan collided range. Earth Planet Sci Lett 45: 133–144

    Google Scholar 

  • Barker SE, Malone SD (in press) Magmatic system geometry at Mount St Helens modeled from the stress field associated with post-eruptive earthquakes. J Geophys Res

  • Bennett JT, Krishnswami S, Turekian KK, Melson WG, Hopson CA (1982) The uranium and thorium decay series nuclides in Mt St Helens effusives. Earth Planet Sci Lett 60:61–69

    Google Scholar 

  • Blake S, Ivey GN (1986a) Magma-mixing and the dynamics of withdrawal from stratified reservoirs. J Volcanol Geotherm Res 27:153–178

    Google Scholar 

  • Blake S, Ivey GN (1986b) Density and viscosity gradients in zoned magma chambers, and their influence on withdrawal dynamics. J Volcanol Geotherm Res 30:210–230

    Google Scholar 

  • Boden DR (1989) Evidence for step-function zoning of magma and eruptive dynamics, Toquima caldera complex, Nevada J Volcanol Geotherm Res 37:39–57

    Google Scholar 

  • Carey S, Sigurdsson H (1985) The May 18, 1980 Eruption of Mount St Helens 2. Modeling of dynamics of the Plinian Phase. J Geophys Res 90:2948–2958

    Google Scholar 

  • Carey S, Gardner J, Sigurdsson H (1989) Intensity and magnitude of post-glacial Plinian eruptions at Mount St Lelens (abst). In: Continental magmatism. New Mexico Bureau of Mines and Mineral Resources Bull 131:43

    Google Scholar 

  • Carey S, Sigurdsson H, Gardner JE, Criswell W (1990) Variations in column height and magma discharge during the May 18, 1980 eruption of Mount St Helens. J Volcanol Geotherm Res 43:99–112

    Google Scholar 

  • Carroll MR, Rutherford MJ (1987) The stability of igneous anhydrite: experimental results and implications for sulfur behavior in the 1982 El Chichon trachyandesite and other evolved magmas. J Petrol 28:781–801

    Google Scholar 

  • Casadevall TJ, Johnston DA, Harris DM, Rose WI, Malinconico LL, Stoiber RE, Bornhorst TJ, Williams SN, Woodruff L, Thompson JM (1981) SO2 emission rates at Mount St Helens from March 29 through December, 1980. US Geol surv Prof Paper 1250:193–207

    Google Scholar 

  • Casadevall TJ, Rose W, Gerlach T, Greenland LP, Ewert J, Wunderman R, Symonds R (1983) Gas emissions and the eruptions of Mount St Helens through 1982. Science 221:1383–1384

    Google Scholar 

  • Cashman KV (1988) Crystallization of Mount St Helens 1980–1986 dacite: a quantitative textural approach. Bull Volcanol 50:194–209

    Google Scholar 

  • Cashman KV, Taggart JE (1983) Petrologic monitoring of 1981 and 1982 eruptive products from Mount St Helens. Science 221:1385–1387

    Google Scholar 

  • Chadwick WW Jr, Swanson DA, Iwatsubo EY, Heliker CC, Leighley TA (1983) Deformation monitoring at Mount St Helens in 1981 and 1982. Science 221:1378–1380

    Google Scholar 

  • Chadwick WW Jr, Archuleta RJ, Swanson DA (1988) The mechanics of ground deformation precursory to dome-building extrusions at Mount St Helens 1981–1982. J Geophys Res 93:B5:4351–4366

    Google Scholar 

  • Christiansen RL, Peterson DW (1981) Chronology of the 1980 eruptive activity. US Geol Surv Prof Paper 1250:17–30

    Google Scholar 

  • Crandell DR (1976) Preliminary assessment of potential hazards from future volcanic eruptions in Washington. US Geol Surv Misc Field Studies Map MF-774

  • Crandell DR (1980) Recent eruptive history of Mount Hood, Oregon, and potential hazards from future eruptions. US Geol Surv Bull 1492:1–81

    Google Scholar 

  • Crandell DR (1987) Deposits of pre-1980 pyroclastic flows and lahars from Mount St Helens volcano, Washington. US Geol Surv Prof Paper 1444:1–91

    Google Scholar 

  • Crandell DR, Mullineaux DR (1978) Potential hazards from future eruptions of Mount St Helens. US Geol Surv Bull 1383-C:1–26

    Google Scholar 

  • Criswell CW (1987) Chronology and pyroclastic stratigraphy of the May 18, 1980 eruption of Mount St Helens, Washington. J Geophys Res 92:10237–10266

    Google Scholar 

  • Criswell CW (1989) Volumes and compositional variations of the May 18, 1980 eruption of Mount St Helens: implications for eruption forecasts (abst). In: Continental magmatism. New Mexico Bureau of Mines and Mineral Resources Bull 131:62

  • Delaney PT, Pollard DD, Ziony JI, McKee EH (1986) Field relations between dikes and joints: emplacement processes and paleostress analysis. J Geophys Res 91:4920–4938

    Google Scholar 

  • Devine JD, Sigurdsson H, Davis AN, Self S (1984) Estimates of sulfur and chlorine yield to the atmosphere from volcanic eruptions and potential climate effects. J Geophys Res 89:6309–6325

    Google Scholar 

  • Dvorak J, Okamura AT, Mortensen C, Johnson MJS (1981) Summary of electronic tilt studies at Mount St Helens. US Geol Surv Prof Paper 1250:169–174

    Google Scholar 

  • Endo ET, Dzurisin D, Murray T, Syverson K (1987) The rate of magma ascent during dome-building at Mount St Helens (abst). Abstract volume, Hawaii Symposium on How Volcanoes Work:64

  • Endo ET, Dzurisin D, Swanson DA (1990) Geophysical and observational constraints for ascent rates of dacitic magma at Mount St Helens In: Ryan MP (ed) Magma transport and storage. Wiley, New York, pp 317–334

    Google Scholar 

  • Evarts RC, Ashley RP, Smith JG (1987) Geology of the Mount St Helens area: record of discontinuous volcanic and plutonic activity in the Cascade arc of southern Washington. J Geophys Res 92:10155–10169

    Google Scholar 

  • Fink JH, Malin MS, Anderson SW (1990) Intrusive and extrusive growth of the Mount St Helens lava dome. Nature 348:435–437

    Google Scholar 

  • Gerlach TM, Casadevall TJ (1986) Fumarole emissions at Mount St Helens volcano, June 1980 to October 1981; degassing of a magma-hydrothermal system. J Volcanol Geotherm Res 28:141–160

    Google Scholar 

  • Gerlach TM, Westrich HR, Casadevall TJ (1990) High sulfur and chlorine magmas during the 1989–90 eruption of Redoubt volcano, Alaska (abst). Am Geophys Union Trans (EOS) 71:1702

    Google Scholar 

  • Glicken H, Meyer W, Sabol M (1989) Geology and ground-water hydrology of Spirit Lake blockage, Mount St Helens, Washington, with implications for lake retention. US Geol Surv Bull 1789:1–33

    Google Scholar 

  • Halliday AN, Fallick AE, Dickin AP, Mackenzie AB, Stephens WE, Hildreth W (1983) The isotopic and chemical evolution of Mount St Helens. Earth Planet Sci Lett 63:241–256

    Google Scholar 

  • Heliker CC (1984) Inclusions in the 1980–83 dacite of Mount St Helens, Washington. MSc thesis. Western Washington University: 1–185

  • Hill PM, Rutherford MJ (1989) Experimental study of amphibole breakdown in Mount St Helens dacite with applications to magmatic ascent rate determinations (abst). New Mexico Bureau of Mines and Mineral Resources Bull 131:131

    Google Scholar 

  • Hoblitt RP (1989) Day 3: The Kalama eruptive period, southwest and south flanks In: Field excursions to volcanic terranes in the western United States II: Cascades and Intermountain West. New Mexico Bureau of Mines and Mineral Resources Memoir 47:65–69

  • Hoblitt RP, Crandell DR, Mullineaux DR (1980) Mount St Helens eruptive behavior during the past 1,500 yr. Geology 8:555–559

    Google Scholar 

  • Hoblitt RP, Miller CD, Vallance JW (1981) Origin and stratigraphy of the deposit produced by the May 18 directed blast. US Geol Surv Prof Paper 1250:401–419

    Google Scholar 

  • Hopson CA, Melson WG (1980) Mount St Helens eruptive cycles since 100 a. d. (abst). American Geophysical Union Trans (EOS) 61:1132–1133

    Google Scholar 

  • Hopson CA, Melson WG (1984) Eruption cycles and plug-domes at Mount St Helens (abst). Geol Soc Am Abst with Programs 16:544

    Google Scholar 

  • Hopson CA, Melson WG (1990) Compositional trends and eruptive cycles at Mount St Helens. Geosci Can 17:131–141

    Google Scholar 

  • Irvine TN (1967) The Duke Island ultramafic complex, southeastern Alaska. In: Wyllie PJ (ed) Ultramafic and related rocks. Wiley, New York, pp 84–96

    Google Scholar 

  • Jaeger JC (1957) The temperature in the neighborhood of a cooling intrusive sheet. Am J Sci 255:306–316

    Google Scholar 

  • James OB (1971) Origin and emplacement of the ultramafic rocks of the Emigrant Gap area, California. Jour Petrology 12:523–560

    Google Scholar 

  • Leeman WP, Smith DR, Hildreth W, Palacz Z, Rogers N (1990) Compositional diversity of Late Cenozoic basalts in a transect across the southern Washington Cascades: Implications for subduction zone magmatism: J Geophys Res 95:19561–19582

    Google Scholar 

  • Lees JM, Crosson RS (1989) Tomographic inversion for three dimensional velocity structure of Mount St Helens using earthquake data. J Geophys Res 94:5716–5728

    Google Scholar 

  • Lipman PW, Mullineaux DR (eds) (1981) The 1980 eruptions of Mount St Helens, Washington. US Geol Surv Prof Paper 1250

  • Lipman PW, Moore JG, Swanson DA (1981a) Bulging of the north flank before the May 18 eruption — geodetic data. US Geol Surv Prof Paper 1250:143–156

    Google Scholar 

  • Lipman PW, Norton DR, Taggart JE Jr, Brandt EL, Engleman EE (1981b) Compositional variations in 1980 magmatic products. US Geol Surv Prof Paper 1250:631–640

    Google Scholar 

  • Malone SD (1990) Mount St Helens, the 1980 rewakening and continuing seismic activity. Geosci Can 17:146–149

    Google Scholar 

  • Mellors RA, Waitt RB, Swanson DA (1988) Generation of pyroclastic flows and surges by hot-rock avalanches from the dome of Mount St Helens volcano, USA. Bul Volcanol 58:14–25

    Google Scholar 

  • Melson WG (1983) Monitoring the 1980–1982 eruptions of Mount St Helens: compositions and abundances of glass. Science 221:1387–1391

    Google Scholar 

  • Merzbacher C, Eggler DH (1984) A magmatic geohygrometer: application to Mount St Helens and other dacitic magmas. Geology 12:587–590

    Google Scholar 

  • Miller CD, Mullineaux DR, Crandell DR (1981) Hazards assessments at Mount St Helens. In: Lipman PW, Mullineaux DR (eds) The 1980 eruptions of Mount St Helens, Washington. US Geol Surv Prof Paper 1250:789–802

  • Mooney WD, Weaver CS (1989) Regional crustal structure and tectonics of the Pacific coastal states; California, Oregon, and Washington. Geol Soc Am Mem 172:129–161

    Google Scholar 

  • Moore JG, Albee WC (1981) Topographic and structural changes, March–July 1980 — photogrammetric data. US Geol Surv Prof Paper 1250:123–134

    Google Scholar 

  • Moran S, Malone SD (1990) Recent micro-seismic activity at Mt St Helens and its implications for the evolution of the deeper magmatic system (abst). Am Geophys Union Trans (EOS) 71:1693–1694

    Google Scholar 

  • Mullineaux DR (1976) Preliminary map of volcanic hazards in the 48 conterminous United States. US Geol Surv Misc Field Studies Map MF-786

  • Mullineaux DR (1986) Summary of pre-1980 tephra-fall deposits erupted from Mount St Helens, Washington State, USA. Bull Volcanol 48:17–26

    Google Scholar 

  • Mullineaux DR, Crandell DR (1981) The eruptive history of Mount St Helens. US Geol Surv Prof Paper 1250:3–15

    Google Scholar 

  • Nakamura K (1977) Volcanoes as possible indicators of tectonic stress orientation — principle and proposal. J Volcanol Geotherm Res 2:1–16

    Google Scholar 

  • Newhall CG (1982) A method for estimating intermediate- and long-term risks from volcanic activity, with an example from Mount St Helens, Washington. US Geol Surv Open-File Report 82-396:1–50

    Google Scholar 

  • Pallister JS, Hoblitt RP (1985) Magma mixing at Mount St Helens (abst). Am Geophys Union Trans (EOS) 66:111

    Google Scholar 

  • Pallister JS, Heliker C, Hoblitt RP (in press) Glimpses of the active pluton below Mount St. Helens (abst). Am Geophys Union Trans (EOS) 72

  • Pearce JA (1982) Trace element characteristics of lavas from destructive plate margins. In: Thorpe RS (ed) Andesites. Wiley, New York, pp 525–548

    Google Scholar 

  • Rutherford MJ (1990) Experimental study of dehydration and crystallization produced by decompression of dacites: implications for magma ascent rates (abst). Goldschmidt Conf Prog Abst 78

  • Rutherford MJ, Devine JD (1988) The May 18 eruption of Mount St Helens. 3. Stability and chemistry of amphibole in the magma chamber. J Geophys Res 93 B10:11949–11959

    Google Scholar 

  • Rutherford MJ, Sigurdsson H, Carey S, Davis A (1985) The May 18, 1980, eruption of Mount St Helens 1. Melt composition and experimental phase equilibria. J Geophys Res 90 B4:2929–2947

    Google Scholar 

  • Sager JW, Chambers DR (1986) Design and construction of the Spirit Lake outlet tunnel, Mount St Helens, Washington. In: Schuster RL (ed) Landslide dams: processes, risk, and mitigation. Am Soc Civil Engineers Geotechnical Special Publication 3:42–58

  • Sarna-Wojcicki AM, Shipley S, Waitt RB Jr, Dzurisin D, Woods SH (1981) Areal distribution, thickness, mass, volume, and grain size of air-fall ash from the six major eruptions of 1980. US Geol Surv Prof Paper 1250:577–600

    Google Scholar 

  • Scandone R, Malone SD (1985) Magma supply, magma discharge and readjustment of the feeding system of Mount St Helens during 1980. J Volcanol Geotherm Res 23:239–262

    Google Scholar 

  • Scarfe CM, Fujii T (1987) Petrology of crystal clots in the pumice of Mount St Helens' March 19, 1982 eruption; significant role of Fe−Ti oxide crystallization. J Volcanol Geotherm Res 34:1–14

    Google Scholar 

  • Shemeta JE, Weaver CS (1986) Seismicity accompanying the May 18, 1980 eruption of Mount St Helens, Washington. In: Keller SAC (ed) Mount St Helens: five years later. Eastern Washington University Press, Cheney, WA, 44–58

    Google Scholar 

  • Sigurdsson H (1982) Volcanic pollution and climate: the 1783 Laki eruption. EOS Trans Am Geophys Union 63:601–602

    Google Scholar 

  • Sillitoe RH (1973) The tops and bottoms of porphyry copper deposits. Econ Geol 68:799–815

    Google Scholar 

  • Smith DR (1984) The petrology and geochemistry of High Cascade volcanics in southern Washington: Mount St Helens volcano and the Indian Heaven basalt field. Ph D dissertation, Rice University, Houston, Texas: 1–409

  • Smith DR, Leeman WP (1982) Mineralogy and phase chemistry of Mount St Helens tephra sets W and Y as keys to their identification. Quat Res 17:211–227

    Google Scholar 

  • Smith DR, Leeman WP (1987) Petrogenesis of Mount St Helens dacitic magmas. J Geophys Res 92. B10:10313–10334

    Google Scholar 

  • Snoke AW, Sharp WD, Wright JE, Saleeby JB (1982) Significance of mid-Mesozoic periodotitic to dioritic intrusive complexes, Klamath Mountains-western Sierra Nevada, California. Geology 10:160–166

    Google Scholar 

  • Spera FJ, Yuen DA, Greer JC, Sewell G (1986) Dynamics of magma withdrawal from stratified magma chambers. Geology 14:723–726

    Google Scholar 

  • Stanley WD, Finn C, Plesha JL (1987) Tectonics and conductivity structures in the southern Washington Cascades. J Geophys Res 92:10179–10193

    Google Scholar 

  • Swanson DA, Holcomb RT (1990) Regularities in growth of the Mount St Helens dacite dome, 1980–1986. In: Fink JH (ed) Lava flows and domes. Springer, New York, pp 3–24

    Google Scholar 

  • Swanson DA, Lipman PW, Moore JG, Heliker CC, Yamashita KM (1981) Geodetic monitoring after the May 18 eruption. US Geol Surv Prof Paper 1250:157–168

    Google Scholar 

  • Swanson DA, Casadevall TJ, Dzurisin D, Malone SD, Newhall CG, Weaver CS (1983) Prediction of eruptions at Mount St Helens, June 1980 through December 1982. Science 221:1369–1376

    Google Scholar 

  • Swanson DA, Dzurisin D, Holcomb RT, Iwatsubo EY, Chadwick WW, Casadevall TJ, Ewert JW, Heliker CC (1987) Growth of the lava dome at Mount St Helens, Washington (USA) 1981–1983. Geol Soc Am Sp Paper 212:1–16

    Google Scholar 

  • Taggart JE, Lindsay JR, Scott BA, Vivit DV, Bartel AJ, Stewart KC (1987) Analysis of geologic materials by X-ray fluorescence spectrometry. In: Badecker PA (ed) Methods for geochemical analysis. US Geol Surv Bull 1770. pp E1–E19

  • Thompson RN, Morrison MA, Dicken AP, Hendry GL (1983) Continental flood basalts ... Arachnids rule OK? In: Hawkes-worth CJ, Norey MJ (ed) Continental basalts and mantle xenoliths. Shiva, Cambridge MA, pp 158–185

    Google Scholar 

  • US Army Corps of Engineers (1986) Mount St Helens, Washington — Toutle, Cowlitz and Columbia Rivers. Portland District, Sedimentation Design Memorandum 3

  • Waitt RB Jr, Pierson TC, MacLeod NS, Janda RJ, Voight B, Holcomb RT (1983) Eruption-triggered avalanche, flood, and lahar at Mount St Helens — Effects of winter snowpack. Science 221:1394–1397

    Google Scholar 

  • Walsh JB (1975) An analysis of local changes in gravity due to deformation. Pure Appl Geophys 113:97–106

    Google Scholar 

  • Weaver CS, Grant WC, Malone SD, Endo ET (1981) Post-May 18 seismicity: volcanic and tectonic implications. US Geol Surv Prof Paper 1250:109–122

    Google Scholar 

  • Weaver CS, Zollweg JE, Malone SD (1983) Deep earthquakes beneath Mount St Helens: evidence for magmatic gas transport? Science 221:1391–1394

    Google Scholar 

  • Weaver CS, Grant WC, Shemeta JE (1987) Local crustal extension at Mount St Helens, Washington. J Geophys Res 92:10170–10178

    Google Scholar 

  • Williams DL, Abrams C, Finn C, Dzurisin D, Johnson DJ, Denlinger R (1987) Evidence from gravity data for an intrusive complex beneath Mount St Helens. J Geophys Res 92:10207–10222

    Google Scholar 

  • Wright TL, Doherty PC (1970) A linear programming and least squares method for solving petrologic mixing problems. Geol Soc Am Bull 81:1995–2008

    Google Scholar 

  • Yamaguchi DK (1983) New tree-ring dates for recent eruptions at Mount St Helens. Quat Res 20:246–250

    Google Scholar 

  • Yamaguchi DK (1985) Tree-ring evidence for a two-year interval between recent prehistoric explosive eruptions of Mount St Helens. Geology 13:554–557

    Google Scholar 

  • Yamaguchi DK (1986) Interpretation of cross correlation between tree-ring series. Tree-ring Bull 46:47–54

    Google Scholar 

  • Yamaguchi DK, Lawrence DB, Hoblitt RP (1990) A new tree-ring date for Mount St Helens' “Floating Island” lava flow. Bull Volcanol 52:545–550

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Pallister, J.S., Hoblitt, R.P., Crandell, D.R. et al. Mount St. Helens a decade after the 1980 eruptions: magmatic models, chemical cycles, and a revised hazards assessment. Bull Volcanol 54, 126–146 (1992). https://doi.org/10.1007/BF00278003

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00278003

Keywords

Navigation









ApplySandwichStrip

pFad - (p)hone/(F)rame/(a)nonymizer/(d)eclutterfier!      Saves Data!


--- a PPN by Garber Painting Akron. With Image Size Reduction included!

Fetched URL: http://link.springer.com/article/10.1007%2FBF00278003

Alternative Proxies:

Alternative Proxy

pFad Proxy

pFad v3 Proxy

pFad v4 Proxy