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University of South Florida Scholar Commons School of Geosciences Faculty and Staff School of Geosciences Publications 8-1992 Evidence of Regional Structural Controls on Vent Distribution: Springerville Volcanic Field, Arizona Charles B. Connor Florida International University, [email protected] Christopher Condit University of Massachusetts Larry S. Crumpler Brown University Jayne C. Aubele Brown University Follow this and additional works at: https://scholarcommons.usf.edu/geo_facpub Part of the Earth Sciences Commons Scholar Commons Citation Connor, Charles B.; Condit, Christopher; Crumpler, Larry S.; and Aubele, Jayne C., "Evidence of Regional Structural Controls on Vent Distribution: Springerville Volcanic Field, Arizona" (1992). School of Geosciences Faculty and Staff Publications. 1655. https://scholarcommons.usf.edu/geo_facpub/1655 This Article is brought to you for free and open access by the School of Geosciences at Scholar Commons. It has been accepted for inclusion in School of Geosciences Faculty and Staff ubP lications by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. JOURNAL OF GEOPHYSICAL RESEARCH,VOL. 97, NO. B9, PAGES 12,349-12,359,AUGUST 10, 1992 Evidenceof RegionalStructural Controls on Vent Distribution: SpringervilleVolcanic Field, Arizona CHARLESB. CONNOR Departmentof Geology,Florida International University, Miami CH]H•OP• D. CONDrr Departmentof Geologyand Geography, University of Massachusetts,Amherst LARRY S. CRUMPLERAND JAYNE C. AUBELE Departmentof GeologicalSciences, Brown University, Providence, Rhode Island Quantitativeanalysis of the geographicdistribution of ventsand comparison with regional structural, petrologle,and vent age data provide insight into the processes governing the emplacement of vents in theSpringerville volcanic field, Arizona. A totalof 409vents in theSpringerville volcanic field (SVF) havea meandistance to nearestneighbor vents of 955 m, a muchcloser spacing than is commonin some platform-typevolcanic fields. Basedupon a clusteranalysis search radius parameter of 4500m, these ventscomprise seven geographic clusters, with only five outlyingvents occurring in the entirefield. Cindercone clusters in the westemportion of the field are significantlyolder than clusters in the eastern portionof the field (p valueof <0.001),and there is a tendencyfor cluster age to decreaseto the east. This is particularlyevident when mean cluster ages are calculated for tholelite,alkaline olivine basalt, and evolvedalkaline rock types independently. Application of thetwo-point azimuth and Hough transform methodsdemonstrates that regional cinder cone alignments transect these clusters. The most prominent of thesealignments trend ENE in theeastern portion of thefield and WNW in thewestern portion of thefield, creatingan overall arcuate pattern that is subparallelto the trend of theMogollon Rim andthe Colorado Plateau/TransitionZone boundary. These observations suggest that vents(and clusters) migrated from westto eastin responseto platemotion, but the generalpattern of ventmigration was complicated by regionalstructures, which enhanced the volume and duration of magmatismin some areas. The fractures or faultsimplied by vent alignments indicate that Shmin is orientedradial to theColorado Plateau in theSVF. Preferredvent alignment orientations may be relatedto extensionresulting from plateau uplift, and to a muchsmaller degree from a minorBasin and Range imprint. While regionalin extent,the implied structuresappear to differsignificantly from some of thosein severalother plateau-marginal fields in that theycannot be relatedto majorreactivated Precambrian structures. Our vent alignment data differ from thoseseen by otherworkers in theZuni-Bandera and Mount Taylor fields, suggesting the stress field for the SVF is differentfrom otherfields in the proposedJemez lineament. The stressfield impliedby vent alignmentdata, combined with structuraldata, suggests that the southwesterntectonic boundary of the ColoradoPlateau of Brumbaugh(1987) should be extendedsoutheastward to include the SVF at theplateau's southernboundary. 1. INTRODUCTION 1979], clusteranalysis [Connor, 1987, 1990], the Hough 1.1. Intent transform[Wadge and Cross,1988], and the two-pointazimuth method[Lutz, 1986;Wadge and Cross,1988; Zhangand Lutz, The apparentcorrelation between regional structures and 1989]. The results of our vent distribution analysis are ventalignments in manycinder cone fields has suggested that comparedwith structuraldata collectedin the field. This ventsare locatedat the top of vertical fracturesalong which comparisonis usedto showthe relationshipbetween observed magmaascends [Kear, 1964; Nakamura,1977; Settle, 1979]. patternsin cinder cone distributionand regional crustal Ventalignments and parallel dikes [Delaney et al., 1986]have structure and to comment on the implied stress field alsobeen used by many workers[e.g., Zobackand Zoback, surroundingthe SVF. The analysisserves to clarify the 1980, 1989; Zoback, 1989; Aldrich and Laughlin, 1984] as relationshipbetween SVF volcanismand the neotectonic regionalstress orientation indicators. One of the fundamental structureswhich dominate the geology of the region. In weaknessesimplicit in usingthese kinds of data is that there addition, these data are examined for clues regarding the has beena lack of rigor in definingvent alignmentswithin mechanismsgoverning the timing andlocation of cindercone volcanic fields, where vent density often makes alignment emplacementwithin the field. recognitiondifficult. In thispaper we useseveral quantitative methodsto searchfor vent clustersand alignmentsin the late 1.2. Background:Regional Setting Tertiary-QuaternarySpringerville volcanic field (SVF), located on the southernmargin of the ColoradoPlateau. These Cindercone volcanismhas been widespreadon the southern methods include univariate statistics [Porter, 1972; Settle, part of the ColoradoPlateau physiographic province during thelate Tertiary and throughout much of theQuaternary. With the exceptionof the Hopi Buttes,all of this volcanismhas Copyfight1992 by the AmericanGeophysical Union. been concentrated within seven volcanic fields located near the Papernumber 92JB00929. marginsof theplateau. The Springervillevolcanic field is the 0148-0227/92/9ZIB-00929 $05.00 southernmostof thesefields (Figure 1); its southernmostflows 12,349 12,350 CONNORET AL.: CONTROL•ON VENT DISTRIBUTION, SPRINOERVIU.E VOLCANIC FIELD 114ø 109ø 103ø •ii:'"'"•WesternGrandCanyon ' - Jemez• •iiiii• i ,_, """•iii:•:':"::::'"':'::::.-....-'•lI ••' i!•SanFranciscø' Ho........Colorado IPlateau Mount Taylor ':,.•,_ ':'••'.:.:..:.':••i•i•::::'':::''' '::•:':':• '-• ! I i•'• r-.•,.'"'""--"""'"'"'""'"'• .....•"' '•:•:•• " •"" • If iel d. field,•:'.'..'"•i•t ' / v /. - I •........ ' • I • •' "• '• .•jljt•Flagstaff I \ - ':•..'?f •. / ' } _ •iiiiii'.:::•,,::.•u-.-o- I '.'•? • J #Albuquerque • \••' • • ••::'"•::::•c[""• Hackberry..•.:•, •__••'•:':'•'':• •., •!, • , High '. •[•• ' ",•':':•::'"":":•:iii:'":':"::•--I •' \ Plains ', "'-' X..._ __ )), ! I(white Uøun I • • Zone Grande • • I Rift BasinandRange '• "----I.i.':•;•/• • .... x, • .... • • 32ø ___1 , km Fig. 1. The Springervillevolcanic field is locatedalong the southernmargin of the ColoradoPlateau, in centraleast Arizona.Physiographic provinces of the areadelineated. The Moõollon Rim is a topographicescarpment which defines the boundarybetween the TransitionZone and the Colorado?lateau, south of the SVF. Shadedareas indicate volcanic fields lessthan 5 m.y.old, outlined areas indicate volcanic fields 5 to 16m.y. old [fromWolfe et al., 1983].The Jemcz lineament [Aldrichand Laughlin,1984] is thoughtto be comprisedof volcanicfields and associated structures extending from the Jemezvolcanic Held to thesouthwest, through the MountTaylor, Zuni-Bandcra, and Springerville fields. straddle the Mogollon Rim, which forms the physiographic 1.3. Background: SpringervilleVolcanic Field boundary between the Colorado Plateau and the Transition Zone. Geophysical models across the Transition Zone The SVF comprises409 vents distributedover an area of betweenthe ColoradoPlateau and Basin and Range(Figure 1) approximately3000 km 2, locatedjust north of the9- to7- show a significant change in depth to the mantle from m.y.-old Mount Baldy (White Mountains) trachyte shield approximately40 km in the interior of the plateau,to 22 km volcano (Figure 2; Nealey [1989]). The vent structuresare in the Basin and Range [Brumbaugh, 1987; Warren, 1969]. dominantlycinder conesbut include spattercones, two shield Near the SVF, this changestarts near the northernboundary of volcanoes,four fissurevents, and five maar craters. Although the TransitionZone (the Mogollon Rim) about25 lcmWSW of thereare someolder lava flows [Conditet al., 1992; Cooperet the SVF, where the seismicrefraction study of Warren [1969] al., 1990; Condit, 1984], the vents in this study were active suggestsa depth to the Moho of about 40 kin. South of this between2.1 and 0.3 m.y. ago and eruptedapproximately 300 area the TransitionZone is further characterizedby a change km3 ofbasaltic lavas of dominantlyalkalic affinities (alkali- from flat lying relatively undisturbedPaleozoic rocks to a olivine basalt(=47 vol %) and hawaiite (=28 vol %) [Condit et setting dominated by Basin and Range faults and increased al., 1989]). Tholeiite (=24 vol %) and a limited number of seismicity [Brumbaugh, 1987; Keller et al., 1979; Thompson more evolved alkalic rocks (mugeariteand benmoreite,<1
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  • REVISION 1 Intra-Eruptive Trachyte

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    1 REVISION 1 2 Intra-eruptive trachyte-phonolite transition: natural evidences and 3 experimental constraints on the role of crystal mushes 4 5 Marco Brenna1*, Alessio Pontesilli1, Silvio Mollo2, Matteo Masotta3, Shane J. Cronin4, Ian 6 E.M. Smith4, Mohammed Rashad Hassan Moufti5, Piergiorgio Scarlato6 7 8 1 Geology Department, University of Otago, Dunedin, New Zealand 9 2 Dipartimento di Scienze della Terra, Sapienza Università di Roma, Rome, Italy 10 3 Dipartimento di Scienze della Terra, Università di Pisa, Pisa, Italy 11 4 School of Environment, University of Auckland, Auckland, New Zealand 12 5 Faculty of Earth Sciences, King Abdulaziz University, Jeddah, Saudi Arabia 13 6 Istituto Nazionale di Geofisica e Vulcanologia, Roma, Italy 14 * corresponding author: [email protected] 15 16 ABSTRACT 17 The generation of silica undersaturated phonolite from silica saturated trachytes is 18 uncommon, as it implies the crossing of the thermal barrier and critical plane of silica 19 undersaturation. Nevertheless, a co-genetic suite displaying compositional transition from 20 benmoreite-trachyte to phonolite has been observed within the Al Shaatha pyroclastic 21 sequence in the Harrat Rahat Volcanic Field (Kingdom of Saudi Arabia). We performed 22 crystallization experiments on benmoreite and trachyte starting compositions in order to 23 simulate the pressure-temperature-volatile conditions that generated the observed liquid line 24 of descent. The experimental conditions were 200-500 MPa, 850-1,150 °C, 0-10 wt.% H2O, 25 0.0-0.5 wt.% CO2 and NNO+2 oxygen buffer. The experimental mineral assemblage consists 26 of clinopyroxene, feldspar and titanomagnetite, as well as glass in variable proportions.
  • Hawaii Volcanoes National Park Geologic Resources

    Hawaii Volcanoes National Park Geologic Resources

    National Park Service U.S. Department of the Interior Natural Resource Program Center Hawai‘i Volcanoes National Park Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2009/163 THIS PAGE: Geologists have long been monitoring the volcanoes of Hawai‘i Volcanoes National Park.k. Here lava cascades during the 1969-1971 Mauna Ulu eruption of Kīlauea Vollcano. Note the Mauna Ullu fountain in tthee background. U.S. Geological Survey Photo by J. B. Judd (12/30/1969). ON THE COVER: Continuously erupting since 1983, Kīllaueaauea Vollcanocano continues to shape Hawai‘i Volcanoes National Park. Photo courtesy Lisa Venture/University of Cincinnati. Hawai‘i Volcanoes National Park Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2009/163 Geologic Resources Division Natural Resource Program Center P.O. Box 25287 Denver, Colorado 80225 December 2009 U.S. Department of the Interior National Park Service Natural Resource Program Center Denver, Colorado The National Park Service, Natural Resource Program Center publishes a range of reports that address natural resource topics of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate high-priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner.