Date File Created Name of Creator 2/1/2011 Josh Rosera - UNC GeoRef Data 2008-109892 DN GeoRef TI Gradients in silicic eruptions caused by rapid inputs from above and below rather than protracted chamber differentiation AU "Knesel, Kurt M; Duffield, Wendell A" AF "Department of Earth Sciences, University of Queensland, Brisbane, Qld 4072, Australia" AF "Geology Department, Northern Arizona University, Flagstaff, AZ, 86011, USA" SP 181 SO "Journal of Volcanology and Geothermal Research, vol. 167, pp. 181-197, Nov 2007" IS 0377-0273 CD JVGRDQ AB "Gradients in the products of voluminous (10 (super 2) -10 (super 3) km (super 3) ) silicic eruptions are widely attributed to magmatic stratification developed by in situ differentiation over long periods of time (10 (super 4) -10 (super 5) years) in sub-volcanic chambers. Although the pattern of chemical and mineralogical variations may support magmatic zonation in the source reservoir at the time of eruption, evidence for protracted chamber differentiation is often equivocal. We report trace-element concentrations of sanidine phenocrysts measured by inductively coupled plasma mass spectrometry in the rapidly effused lavas of the 100 km (super 3) Taylor Creek Rhyolite, New Mexico, which link much of the eruptive heterogeneity of the domes and flows to mixing of fresh, crystal-poor, incompatible-element-rich, low- (super 87) Sr/ (super 86) Sr magma from below with partially crystallized, roof-rock contaminated, compatible-element-rich, high- (super 87) Sr/ (super 86) Sr magma resident in the shallow crust. Time constraints provided by high-resolution (super 40) Ar/ (super 39) Ar geochronology, reconstruction of the path of geomagnetic secular variation, and calculated cooling histories of overlapping eruptive units suggest that inputs from both above and below modified magma compositions during the lifespan of the dome field over periods as brief as a few hundred years or less. These domes thereby provide evidence that chemical gradients need not exist for protracted periods of time prior to eruption of zoned silica-rich magma. Comparisons with some ignimbrites reinforce this view and highlight the importance of processes occurring both at and below the pre-eruptive storage chamber in production of the chemical zonation in silicic systems." LA English PY 2007 PT Serial; Analytic CP Netherlands (NLD) CL "05A, Igneous and metamorphic petrology" CY "GeoRef, Copyright 2008, American Geological Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands" AN "2008-109892PB Elsevier, Amsterdam, Netherlands (NLD)" Sample Data Item LatDD LongDD Loc_prec Li Be Sc V Cr Co Ni Cu Zn Ga Rb Sr Y Zr Nb Cs Ba La Ce Nd Sm Eu Tb Gd Dy Ho Er Tm Yb Lu Hf Ta Pb Th U Volcanic_Field Rock_Class Rock_Type Age Max_age Min_age Material State Units dd dd ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ma ma ma Method 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 Sample Name SPC-5 33.52638889 -107.97 0.01 13.2 1.15 0.287 0.08 0.062 0.037 0.017 9.9 4.5 23.8 234 44.6 1.32 1.66 0.309 0.48 309 5.97 5.96 1.26 0.195 1.5 0.031 0.179 0.208 0.046 0.144 0.023 0.156 0.021 0.078 0.024 25 0.457 0.09 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico BRH-1 33.52777778 -107.9563889 0.01 12.8 1.69 0.316 0.08 0.52 0.041 0.45 0.85 2.2 23.6 282 37.6 1.86 2.66 0.562 1.03 257 6.21 5.69 1.82 0.326 1.33 0.053 0.304 0.324 0.071 0.211 0.039 0.223 0.032 0.117 0.051 25 0.575 0.147 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico LGR-5 33.54194444 -107.9519444 0.01 15.6 1.52 0.325 0.037 0.273 0.033 0.122 3 2.8 23.2 283 29.1 1.97 2.53 0.371 1.27 193 5.9 5.73 1.69 0.298 1.11 0.051 0.287 0.323 0.07 0.216 0.039 0.235 0.034 0.112 0.034 23 0.691 0.146 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico IDP-1 33.56111111 -108.0166667 0.01 20 7.7 0.27 0.042 0.304 0.038 0.45 3 2.6 27.3 481 8.6 2.48 1.67 1.08 1.36 50.1 6.13 6.57 2.4 0.495 0.611 0.077 0.466 0.438 0.093 0.263 0.04 0.242 0.034 0.096 0.11 33 0.744 0.122 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico BLP-2 33.40388889 -107.9286111 0.01 17.3 5.6 0.509 0.015 0.137 0.059 1.91 1.7 5.6 27 476 6.6 5.03 5.49 5.13 1.59 35.3 6.89 9.48 2.73 0.619 0.575 0.127 0.657 0.852 0.189 0.573 0.093 0.605 0.089 0.276 0.403 39 1.92 0.551 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico AXP-5 33.40083333 -107.9391667 0.01 22.5 7.7 0.364 0.017 0.217 0.046 1.49 3.5 2.1 25.4 471 6.5 3.72 0.678 0.482 0.87 48.3 4.55 6.12 1.9 0.453 0.572 0.098 0.495 0.623 0.138 0.412 0.065 0.408 0.058 0.037 0.04 51 0.93 0.08 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico DGC-1 33.43305556 -107.9494444 0.01 24 9.8 0.307 0.001 0.12 0.049 1.14 0.9 3.8 25.6 500 6.2 0.837 0.658 0.153 1.26 39 3.59 3.7 0.818 0.162 0.55 0.027 0.152 0.163 0.035 0.097 0.014 0.085 0.013 0.029 0.013 60 0.202 0.04 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico KPM-1 33.36638889 -108.0761111 0.01 26.2 0.79 0.21 0.003 0.048 0.021 0.37 2.8 2.2 25 210 30.4 1.009 0.387 0.148 0.298 222 3.57 3.35 0.751 0.139 0.8 0.03 0.153 0.184 0.041 0.115 0.017 0.089 0.013 0.02 0.013 26 0.167 0.042 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico WHC-6 33.36305556 -108.3886111 0.01 10.4 1.36 0.224 0.031 0.111 0.027 0.45 3.5 3 24.2 304 35.7 0.708 0.408 0.138 1.68 292 4.19 3.79 0.787 0.132 0.948 0.024 0.122 0.132 0.029 0.081 0.011 0.066 0.009 0.02 0.013 27 0.167 0.035 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico DMC-1 33.29972222 -107.9786111 0.01 25.3 0.85 0.33 0.019 0.28 0.042 1.85 0.5 2.8 25.5 208 13.1 0.697 0.33 0.157 0.181 101 3.35 3.37 0.598 0.117 0.656 0.021 0.111 0.134 0.029 0.085 0.012 0.069 0.01 0.02 0.013 22 0.201 0.036 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico RWC-1 33.29611111 -107.9575 0.01 18.2 1.2 0.368 0.011 0.001 0.032 0.086 6.9 2.8 24.5 212 30.2 1.99 2.4 0.318 0.72 247 5.34 6.1 1.14 0.205 1.21 0.048 0.222 0.342 0.081 0.252 0.043 0.298 0.042 0.109 0.03 39 0.518 0.165 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico RDM-4 33.31361111 -107.9105556 0.01 32.2 4.9 0.45 0.04 0.037 0.032 0.009 0.74 2.6 27.3 419 5.8 9.96 1.62 0.622 0.98 39.5 6.44 9.92 3.98 1.07 0.426 0.234 1.14 1.58 0.366 1.11 0.181 1.17 0.167 0.085 0.055 29 2.32 0.168 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico RDM-4a 33.31361111 -107.9105556 0.01 33.8 5.3 0.97 0.028 0.009 0.04 1.45 0.88 1.12 27.2 427 5.8 9.81 1.47 0.607 1.02 39.6 6.38 9.71 4.03 1.06 0.43 0.233 1.15 1.63 0.36 1.1 0.177 1.15 0.163 0.075 0.053 27 2.22 0.154 Mogollon-Datil Rhyolite Volcanic 27.9 27.96 27.88 Sanidine New Mexico Method Data 1 SCAN 1990-061003 2 ICPMS 57 3 REG_COR 1990-061003 Reference Data georef# 1990-061003 TI The Taylor Creek Rhyolite of New Mexico; a rapidly emplaced field of lava domes and flows AU "Duffield, Wendell A; Dalrymple, G.B" AN 1990-061003