Jim Luhr's Research Summary and List of Publications

My research effort is focused on the origin of chemical and mineralogical diversity in young volcanic rocks, mostly from Mexico. The basic approach that I use is one followed by volcanologists and petrologists around the world. For a given volcano, or eruptive unit, I seek to establish the volume or mass of material erupted, the age of the eruption, and the chemical and mineralogical compositions of the erupted products. These are the basic data elements necessary for a modern contribution to the growing global database for Earth's volcanoes and eruptive products. Volume estimates are based on field measurements, eruptive ages are established historically or by radiocarbon or 40Ar/39Ar geochronology, and chemical and mineralogical data are obtained using a broad array of analytical instrumentation, some within the Department of Mineral Sciences, and others at research labs external to the SI. Data collected in this manner can be used to address a wide range of key questions, including: How and why do the compositions of magma erupted at a particular volcano change over time? Can such changes provide insight into future eruptive behavior? How are volcanic rock compositions related to plate-tectonic processes on a regional and global scale? Why do some volcanoes erupt relatively benign lava flows, whereas others explosively inject pumice and ash high into the atmosphere and send dangerous pyroclastic flows down their flanks? The latter question in particular lies at the core of my current research. Three years ago we acquired a Fourier-transform infrared spectrometer, which allows me to analyze volcanic glasses for concentrations of water and carbon dioxide, the two principal volatile propellants for explosive volcanic eruptions. We are able to analyze other important volatile elements (F, Cl, and S) using our electron microprobe. I seek to understand the history of volatile elements in magmas, both their original concentrations at the time of magma generation, and their subsequent changes related to degassing during ascent through the crust and upon eruption. To achieve these goals I analyze tiny melt droplets that were trapped in growing crystals at various stages of the magma history. Once encased by the crystal, the melt droplet is armored and protected from further changes until it quenches to glass upon eruption. The deepest entrapped glass inclusions provide windows into the primary volatile contents of magmas. I also work to understand how these primary volatile contents are related to regional plate-tectonic setting and to eruptive behavior. My work is important because it is aimed at better understanding of one of Earth's fundamental phenomena, volcanic activity. The goal is improved knowledge of how magma is generated deep in the Earth, the changes it undergoes during ascent through the crust, and how these are related to eruption style once the magma reaches the surface. This effort will result in better ways to mitigate the hazards that volcanoes pose to humanity. Publications: Luhr, J.F. and Carmichael, I.S.E. (1980) The Colima Volcanic Complex, México: Part I. Post-caldera andesites from Volcán Colima: Contrib Mineral Petrol 71: 343-372. Luhr, J.F. (1980) The Colima Volcanic Complex, México: Part I. Post-caldera andesites from Volcán Colima. Part II. Late-Quaternary cinder cones: Ph.D. dissertation, Univ. Calif., Berkeley. Luhr, J.F. and Carmichael, I.S.E. (1981) The Colima Volcanic Complex, México: Part II. Late-Quaternary cinder cones: Contrib Mineral Petrol 76: 127-147. Luhr, J.F. (1981) Colima: History and cyclicity of eruptions: Volcano News 7: 1-3. Luhr, J.F. and Carmichael, I.S.E. (1982) The Colima Volcanic Complex, México: Part III. Ash- and scoria-fall deposits from the upper slopes of Volcán Colima: Contrib Mineral Petrol 80: 262-275. Giannetti, B. and Luhr, J.F. (1983) The White Trachytic Tuff of Roccamonfina Volcano (Roman Region, Italy): Contrib Mineral Petrol 84: 235-252. Giannetti, B. and Luhr, J.F. (1983) Compositional variations in the Grey Campanian Ignimbrite, Italy: Hydrothermal modification or pre-eruptive fractionation: Bull Volcanol 46-4: 429-431. Luhr, J.F. and Varekamp, J.C., Editors (1984) El Chichón Volcano, Chiapas, México: J Volcanol Geotherm Res 23. Luhr, J.F., Carmichael, I.S.E. and Varekamp, J.C. (1984) The 1982 eruptions of El Chichón Volcano, Chiapas, México: Mineralogy and petrology of the anhydrite-bearing pumices: J Volcanol Geotherm Res 23: 69-108. Varekamp, J.C., Luhr, J.F. and Prestegaard, K.L. (1984) The 1982 eruptions of El Chichón Volcano (Chiapas, México): Character of the eruptions, ash-fall deposits, and gasphase: J Volcanol Geotherm Res 23: 39-68. Rye, R.O., Luhr, J.F. and Wasserman, M.D. (1984) Sulfur and oxygen isotope systematics of the 1982 eruptions of El Chichón Volcano, Chiapas, México: J Volcanol Geotherm Res 23: 109-123. Luhr, J.F., Nelson, S.A., Allan, J.F. and Carmichael, I.S.E. (1985) Active rifting in southwestern México: Manifestations of an incipient spreading-ridge jump: Geology: 13, 1: 54-57. Luhr, J.F. and Carmichael, I.S.E. (1985) The 1759-1774 eruption of Jorullo Volcano, Michoacan, México: the earliest stages of fractionation in calc-alkaline magmas: Contrib Mineral Petrol 90: 142-161. Luhr, J.F. and Carmichael, I.S.E. (1985) Contemporaneous eruptions of calc-alkaline and alkaline magmas along the volcanic front of the Mexican Volcanic Belt: Geofisica Internacional 24-1: 203-216. Luhr, J.F. and Lazaar, P. (1985) The Southern Guadalajara Volcanic Chain, Jalisco, México: Geofisica Internacional: 24-4: 691-700. Luhr, J.F. and Giannetti, B. (1987) The Brown Leucitic Tuff of Roccamonfina Volcano (Roman Region, Italy): Contrib Mineral Petrol 95: 420-436. Luhr, J.F. and Prestegaard, K.L. (1988) Caldera formation at Volcán Colima, México, by a large Holocene volcanic debris avalanche. J Volcanol Geotherm Res 35: 335-348. Luhr, J.F. and Kyser, T.K. (1989) Primary igneous analcime: The Colima minettes. Am Mineral 74: 216-223. Luhr, J.F., Allan, J.F., Carmichael, I.S.E., Nelson, S.A., and Hasenaka, T. (1989) Primitive calc-alkaline and alkaline volcanic rock types from the western Mexican Volcanic Belt. J Geophys Res 94, B4: 4515-4530. Luhr, J.F., Aranda-Gómez, J.J., and Pier, J.G. (1989) Spinel-lherzolite-bearing, Quaternary volcanic centers in San Luis Potosi, México: I. Geology, mineralogy, and petrology. J Geophys Res 94, B6: 7916-7940. Pier, J.G., Podosek, F.A., Luhr, J.F., Brannon, J.C., and Aranda-Gómez, J.J. (1989) Spinel-lherzolite-bearing Quaternary volcanic centers of San Luis Potosi, México: II. Sr and Nd isotopic systematics. J Geophys Res 94, B6: 7941-7951. Luhr, J.F., and Carmichael, I.S.E. (1990) Petrological monitoring of cyclical eruptive activity at Volcán Colima, México. J Volcanol Geotherm Res 42: 235-260. Luhr, J.F. (1990) Experimental phase relations of water- and sulfur-saturated arc magmas and the 1982 eruptions of El Chichón Volcano. J Petrol 31, 5: 1071-1114. Luhr, J.F., and Carmichael, I.S.E. (1990) Geology of Volcán de Colima. Univ. Nac. Auto. México, Inst. Geol. Bol. 107, 101 p. Giannetti, B., and Luhr, J.F. (1990) Phlogopite-clinopyroxenite nodules from high-K magmas, Roccamonfina Volcano, Italy: evidence for a low-pressure metasomatic origin. Earth Planet Sci Lett 101: 404-424. Housh, T., and Luhr, J.F. (1991) Experimental plagioclase-melt equilibria for water-saturated andesite and basalt. Am Mineral, 76: 477-492. Luhr, J.F., and Williams, S.N. (1991) Volcanology. Rev Geophys Space Phys, supplement: 513-531. Luhr, J.F. (1991) Volcanic shade causes cooling. Nature, 354: 104-105. Allan, J.F., Nelson, S.A., Luhr, J.F., Carmichael, I.S.E., Wopat, M. and Wallace, P.J. (1991) Pliocene-Recent rifting in SW México and associated volcanism: An exotic terrane in the making. In: J.P. Dauphin and B.A. Simoneit, eds., The Gulf and Peninsular Province of the Californias. Am Assoc Petrol Geol Mem 47: 425-445. Aranda-Gómez, J.J., Luhr, J.F., and Pier, J.G. (1992) The La Breña - El Jagüey Maar Complex, Durango, México: I. Geological evolution. Bull Volcanol, 54: 393-404. Pier, J.G., Luhr, J.F., Podosek, F.A., and Aranda-Gómez, J.J. (1992) The La Breña - El Jagüey Maar Complex, Durango, México: II. Petrology and geochemistry. Bull Volcanol, 54: 405-428. Luhr, J.F. (1992) Fuji and Hakone: Commentary. Nat. Geogr. Res. Explor., 8: 121-122. Aranda-Gómez, J.J., Luhr, J.F., and Pier, J.G. (1992) A new type of maar volcano from the state of Durango - The El Jagüey - La Breña Complex reinterpreted; A discussion. Univ Nac Autón México, Inst Geologia Revista 9, 2: 204-210. Luhr, J.F. (1992) Slab-derived fluids and partial melting in subduction zones: Insights from two contrasting Mexican volcanoes (Colima and Ceboruco). J. Volc. Geotherm. Res., 54: 1-18. Aranda-Gómez, J.J., Luhr, J.F., Pier, J.G., and Nieto-Samaniego, A.F. (1993) Xenolitos del manto y de la base de la corteza en el estado de San Luis Potosí, México. Universidad Nacional Autónoma de México, Instituto de Geología, Boletín 106. Aranda-Gómez, J.J., and Luhr, J.F. (1993) Geology of the Joya Honda and Santo Domingo Maars, San Luis Potosí, México - A visit to the mantle and crustal xenolith localities in the Sierra Madre Terrane. Universidad Nacional Autónoma de México, Instituto de Geología, Field Trip Guidebook A: p. 11-35. Luhr, J.F. (1993) Petrology and geochemistry of pre-caldera andesites and dacites from Volcán Colima, México. Geofís. Intern., 32: 592-603. Luhr, J.F. and Simkin T. (1993) Parícutin: The volcano born in a Mexican cornfield. Geoscience Press, Phoenix, 427 p. Verma, S.P., and Luhr, J.F. (1993) Sr-Nd-Pb isotope and trace element geochemistry of calc-alkaline andesites from Volcán Colima, México. Geofís. Intern., 32: 617-631. Trombold, C.D., Luhr, J.F., Hasenaka, T., and Glascock, M.D. (1993) Chemical characteristics of obsidian from archaeological sites in western Mexico and the Tequila source area: Implications for regional and pan-regional interaction within the northern Mesoamerican periphery. Ancient Mesoamerica, 4: 255-270. Luhr, J.F., Pier, J.G., Aranda-Gómez, J.J., and Podosek, F.A. (1995) Crustal contamination in early basin-and-range hawaiites of the Los Encinos Volcanic Field, central México. Contrib. Mineral. Petrol., 118: 321-339. Luhr, J.F., Aranda-Gómez, J.J., and Housh, T.B. (1995) The San Quintín Volcanic Field, Baja California Norte, México: Geology, petrology, and geochemistry. J. Geophys. Res., 100, B7: 10,353-10,380. Aranda-Gómez, J.J. and Luhr, J.F. (1996) Origin of the Joya Honda maar, San Luis Potosí, México. J. Volcanol. Geotherm. Res., 74: 1-18. Carmichael, I.S.E., Lange, R.A., and Luhr, J.F. (1996) Quaternary minettes and associated lavas of Mascota, western México: A consequence of plate extension above a subduction-modified mantle wedge. Contrib. Mineral. Petrol., 124: 302-333. Hochstaedter, A.G., Ryan, J.G., Luhr, J.F., and Hasenaka, T. (1996) On B/Be ratios in the Mexican Volcanic Belt. Geoch. Cosmochim. Acta., 60: 613-628. Rasskazov, S.V., Kunk, M.J., Luhr, J.F., Bowring, S.A., Brandt, I.S., Brandt, S.B., and Ivanov, A.V. (1996) Episodes of eruptions and compositional variations of the Quaternary lavas in the Baikal Rift System (Ar-Ar and K-Ar dating of volcanism in the Dzhida River area). Russian Geology and Geophysics, 37: 1-12. Luhr, J.F., and Melson, W.G. (1996) Mineral and glass compositions in June 15, 1991 pumices: evidence for dynamic disequilibrium in the Pinatubo dacite. In C.G. Newhall and R.S. Punongbayan, Eds., Fire and mud: Eruptions and lahars of Mount Pinatubo, Philippines. Philippine Institute of Volcanology and Seismology, Quezon City, and University of Washington Press, Seattle, 733-750. Luhr, J.F. (1997) Extensional tectonics and diverse primitive volcanic rocks in the western Mexican Volcanic Belt. Can. Mineral. 35: 473-500. Luhr, J.F. and Aranda-Gómez, J.J. (1997) Mexican peridotite xenoliths and tectonic terranes: Correlations among vent location, texture, temperature, pressure, and oxygen fugacity. J. Petrol. 38: 1075-1112. Luhr, J.F. and Delgado-Granados, H. (1997) Aerial examination of volcanoes along the front of the western Trans-Mexican Volcanic Belt and a visit to Parícutin. Guidebook for Excursion No. 9, International Association of Volcanology and Chemistry of the Earth's Interior, General Assembly, Puerto Vallarta, Mexico, 38 pp. Aranda-Gómez, J.J., Henry, C.D., Luhr, J.F., and McDowell, F.W. (1997) Cenozoic volcanism and tectonics in NW Mexico: A transect across the Sierra Madre Occidental Volcanic Field and observations on extension-related magmatism in the southern Basin and Range and Gulf of California tectonic provinces. Guidebook for Excursion No. 11, International Association of Volcanology and Chemistry of the Earth's Interior, General Assembly, Puerto Vallarta, Mexico, 94 pp. Peng, G., Luhr, J.F., and McGee, J.J. (1997) Factors controlling sulfur concentrations in volcanic apatite. Am. Mineral. 82: 1210-1224. Kimberly, P., Siebert, L., Luhr, J.F., and Simkin, T. (1998) Volcanoes of Indonesia, v. 1.0 (CD-ROM), Smithsonian Institution, Global Volcanism Program, Digital Information Series, GVP-1. Luhr, J.F. (2000) The geology and petrology of Volcán San Juan (Nayarit, México) and the compositionally zoned Tepic Pumice. Journal of Volcanology and Geothermal Research, v. 95, p. 109-156. Jones, A., Siebert, L., Kimberly, P., and Luhr, J.F. (2000) Earthquakes and Eruptions: Temporal and spatial display of earthquake hypocenters, seismic-wave paths, and volcanic eruptions, v. 1.0 (CD-ROM). Smithsonian Institution, Global Volcanism Program, Digital Information Series, GVP-2. Aranda-Gómez, J.J., Henry, C.D., and Luhr, J.F. (2000) Evolución tectonomagmática post-paleocénica de la Sierra Madre Occidental y de la porción meridional de la provincia tectónica de Cuencas y Sierras, México. Boletín de la Sociedad Geológica Mexicana, v. LIII, p. 59-71. Luhr, J.F., Henry, C.D., Housh, T.B., Aranda-Gómez, J.J., and McIntosh, W.C. (2001) Early extension-related hawaiites from the southern Basin and Range Province: Geology and petrology of the Rodeo and Nazas volcanic fields, Durango (México). Geol. Soc. Am. Bull., v. 113, p. 760-773. Lassiter, J.C., and Luhr, J.F. (2001) Osmium abundance and isotope variations in mafic Mexican volcanic rocks: Evidence for crustal contamination and constraints on the geochemical behavior of osmium during partial melting and fractional crystallization. Geochemistry, Geophysics, Geosystems, vol. 2, Paper no. 2000GC000116, published March 14, 2001. Luhr, J.F. (2001) Glass inclusions and melt volatile contents at Parícutin Volcano, México. Contributions to Mineralogy and Petrology, 142: 261-283. Luhr, J.F. (2001) Review of Montserrat's Andesite Volcano, a film by David Lea and Steve Sparks. EOS, Transactions of the American Geophysical Union, v. 82, no. 32, p. 349. Peslier, A.H., Luhr, J.F., and Post, J. (2002) Low water contents in pyroxenes from spinel-peridotites of the oxidized, sub-arc mantle wedge. Earth and Planetary Science Letters 201, p. 69-86. Luhr, J.F. and Logan, M.A.V. (2002) Sulfur Isotope Systematics of the 1982 El Chichón Trachyandesite: An ion microprobe study. Geochimica et Cosmochimica Acta 66, p. 3303-3316. Luhr, J.F., Zobin, V.M., and Taran, Y.A., Editors (2002) Volcán de Colima, México, and its activity in 1997-2000. Journal of Volcanology and Geothermal Research, 117. Luhr, J.F. (2002) Petrology and geochemistry of the 1991 and 1998-1999 lava flows from Volcán Colima, México. Journal of Volcanology and Geothermal Research 117, p. 169-194. Zobin, V.M., Luhr, J.F., Taran, Y.A., Bretón M., Cortés A., De La Cruz-Reyna, S., Domínguez, T., Gavilanes, J.C., Galindo, I.I., Muñíz, J.J., Navarro, C., Ramírez, J.J., Reyes, G.A., Ursúa, M., Velasco, J., Alatorre, E., Santiago, H. (2002) Overview of the 1997-2000 Activity of Volcán de Colima, México. Journal of Volcanology and Geothermal Research 117, p. 1-19. Aranda-Gómez, J.J., Luhr, J.F., Housh, T.B., Connor, C.B., Becker, T, and Henry, C.D. (2003) Synextensional Pliocene-Pleistocene eruptive activity in the Camargo volcanic field, Chihuahua, México. Geological Society of America, Bulletin 115: 298-313. Siebert, L., Calvin, T., Kimberly, P., Luhr, J.F., Kysar, G. (2003) Volcanoes of México (CD-ROM). Smithsonian Institution, Global Volcanism Program, Digital Information Series, GVP-6. Haldar, D. And Luhr, J.F. (2003) The Barren Island volcanism during 1991 and 1994-95: Eruptive style and lava petrology. Geological Society of India, Memoir 52: 313-338. Luhr, J.F., Editor in Chief (2003) Earth. Smithsonian Institution and Dorling Kindersley, 520 pp. Scaillet, B., Luhr, J.F., Carroll, M.R. (2003) Petrological and volcanological constraints on volcanic sulfur emissions to the atmosphere. In: Volcanism and the Earth's Atmosphere, ed. A. Robock. American Geophysical Union, Geophysical Monograph 139: 11-40. Rasskazov, S.V., Luhr, J.F., Bowring, S.A., Ivanov, A.V., Brandt, I.S., Brandt, S.B., Demonterova, E.I., Boven, A.A., Kunk, M., Housh, T., Dungan, M.A. (2003) Late Cenozoic volcanism in the Baikal Rift System: Evidence for formation of the Baikal and Khubsugul basins due to thermal impacts on the lithosphere and collision-derived tectonic stress. Berliner Paläobiologische Abhandlungen, 4: 33-48. Aranda-Gómez, J.J., Housh, T.B., Luhr, J.F., Henry, C.D., Becker, T., Chávez-Cabello, G. (2005) Reactivation of the San Marcos fault during mid-to-late Tertiary extension, Chihuahua, Mexico. In: T.H. Anderson, J.A. Nourse, J.W. McKee, and M.B. Steiner (editors) The Mojave-Sonora Megashear Hypothesis: Development, Assessment, and Alternatives. Geological Society of America Special Paper 393: 509-522. Aranda-Gómez, J.J., Luhr, J.F., Housh, T.B., Valdez-Moreno, G., and Chávez-Cabello, G., (2005) El vulcanismo intraplaca del Cenozoico tardío en el centro y norte de México: una revisión. Número Especial del Primer Centenario de la Sociedad Geológica Mexicana, LVII, 3: 187-225. Luhr, J.F., and Haldar, D. (2006) Barren Island Volcano (NE Indian Ocean): Island-arc high-alumina basalts produced by troctolite contamination. Journal of Volcanology and Geothermal Research, 149: 177-212. Siebert, L., Kimberly, P., Calvin, C., Luhr, J.F., and Kysar Mattietti G. (2006) Volcanoes of Central America (CD-ROM). Smithsonian Institution, Global Volcanism Program, Digital Information Series, GVP-7. Luhr, J.F., Kimberly, P., Siebert, L., Aranda-Gómez, J., Housh, T.B., Kysar Mattieti, G. (2006) México's Quaternary volcanic rocks: Insights from the MEXPET petrological and geochemical database. In Siebe, C., Macías, J.L., and Aguirre-Díaz, G.J., eds., Neogene-Quaternary continental margin volcanism: A perspective from Mexico, Geological Society of America, Special Paper 401: 1-44, doi: 10.1130/2006.2402(01). Wysoczanski, R.J., Wright, I.C., Gamble, J.A., Hauri, E.H., Luhr, J.F., Eggins, S.M., Handler, M.R. (2006) Volatile contents of Kermadec Arc - Havre Trough pillow glasses: Fingerprinting slab-derived aqueous fluids in the mantle sources of arc and back-arc lavas. Journal of Volcanology and Geothermal Research 152: 51-73. Peslier, A. H and Luhr, J. F. (2006) Hydrogen loss from olivines in mantle xenoliths from Simcoe (USA) and Mexico: Mafic alkalic magma ascent rates and water budget of the sub-continental lithosphere. Earth and Planetary Science Letters 242: 302-319.