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Estudio aeromagnético del complejo volcánico de Colima, occidente de México - implicaciones tectónicas y estructurales
López-Loera, Héctor;Urrutia-Fucugauchi, Jaime;Alva-Valdivia, Luis;
Revista mexicana de ciencias geológicas , 2011,
Abstract: results of qualitative and quantitative interpretation of aeromagnetic anomalies over the colima volcanic complex (cvc) and surrounding areas are presented. the area is characterized by magnetic anomalies of distinct amplitude and wavelength associated with volcanic structures and intrusive bodies, including the cvc. we identified 24 aeromagnetic domains in an area of 11,500 km2 around the cvc. we identify, for the first time, new geological structures buried under volcanic products, like faults and intrusive bodies. high amplitude magnetic dipolar anomalies characterize the volcanic structures of colima and nevado de colima volcanoes. cvc deep structure was investigated by using a 2? d magnetic model, finding that the source is related to a possible magmatic chamber of elongated shape, >6.8 km long, in north-south strike with maximum thickness of 5.6 km, which is located at 4.8 m depth beneath the colima volcano. the body extends to 5.6 km south of the colima volcano, with average thickness of about 0.54 km. under nevado de colima volcano, we interpreted a collapsed magmatic chamber, with elongated shape, >5.6 km long and 1.2 km of maximum thickness at a depth of around 5.2 km below the nevado summit. in most of the reduced to the pole magnetic anomaly map, we observed large monopolar anomalies, high amplitude, and long wavelengths associated to the intrusive bodies. three of these anomalies form a 47 km long belt to the nw of the cvc. there are several magnetic anomalies related to iron-ore deposits, i.e., el encino mine (48 km se of cvc) and sierra de manantlán (42 km ese of cvc).
The porphyry metallogenesis of Geza volcanic magmatic arc in NW Yunnan

LI WenChang,YIN GuangHou,YU HaiJun,LU YingXiang,LIU XueLong,

岩石学报 , 2011,
Abstract: The Geza volcanic magmatic arc in the south end part of Yidun island arc is characterized by Indosinian large scale intermediate-acid volcanic magmatic rock in NW zonal distribution.In this paper,we divide this magmatic rock zone into the west Lannitang-Chundu porphyry metallogenesis zone and the east Yaza-Pulang porphyry metsllogenesis zone according to the distribution,type,age,structural environment and metallogenesis,etc.,of the volcanic magmatic rock and indicate the emplacement time of west porphyry z...
Heterogeneous magmas of the Quaternary Sierra Chichinautzin volcanic field (central Mexico): the role of an amphibole-bearing mantle and magmatic evolution processes
Meriggi, Lorenzo;Macías, José Luis;Tommasini, Simone;Capra, Lucia;Conticelli, Sandro;
Revista mexicana de ciencias geológicas , 2008,
Abstract: the quaternary sierra chichinautzin volcanic field (scvf) is located at the volcanic front of the trans-mexican volcanic belt (tmvb), 350 km from the middle american trench where the cocos plate subducts beneath the north american plate. the scvf is characterized by more than 200 monogenetic centers, ranging in composition from rare basalts to dacites. less evolved terms have aphyric to porphyritic textures with phenocrysts of euhedral olivine (± cr-spinels inclusions) + cpx, -whereas evolved terms have porphyritic textures with phenocrysts of pyroxene (cpx>opx), xenocrysts of corroded quartz, and sieve-textured plagioclase from the local basement. regardless of the degree of magmatic evolution, plagioclase occurs as microphenocrysts or in the groundmass. new geochemical and isotopic data presented in this work are in good agreement with previous analyses; however, a new division for the scvf mafic rocks (mgo >6.0 wt.%) is proposed. in fact, although concentrations of large ion lithophile elements (lile) and light to medium rare earth elements (ree) are roughly constant in mafic rocks, tio2 and other high field strength elements (hfse) such as nb are scattered and vary from 0.8 to 1.8 wt.% and from 5 to 30ppm, respectively. these characteristics allow grouping the scvf rocks in two main magmatic series with different tio2-hfse enrichment: high(h)-tio2 and low(l)-tio2, with subordinate transitional samples. additionally, a cinder cone with shoshonitic affinity and extremely high lile/hfse ratio is reported for the first time in central mexico. compositional variability is also observed among the mineral phases of these mafic rocks (e.g., the cr# of spinel hosted in olivine phenocrysts), and the 87sr/86sr ratios that progressively increase from the h-tio2series (0.70307-0.70425) to the l-tio2 series (0.70365-0.70434), up to the shoshonitic scoria (0.70456). the calc-alkaline affinity, lile, and pb positive anomalies of the magmas confirm the occurrence of a subduction
The 1998-1999 eruption of Volcán de Colima, Mexico: an application of Maeda's viscoelastic model
Cabrera-Gutiérrez, R.;Espíndola, J. M.;
Geofísica internacional , 2010,
Abstract: a modifed version of maeda's viscoelastic model of mass ejection is applied to the 1998-1999 eruptive period of volcán de colima, mexico. the model fts reasonably well the observed volume and volume rate of the eruption, assuming a magma chamber with a volume 30 km3 and radius of 1.93 km centered at about 1.7 km below sea level (~ 5.6 km below the summit crater). these fgures are roughly in agreement with gravimetric data. the process of mass emission at colima volcano during the studied period, consisted of slow emission of lava for 2 months. this behavior is attributed to the viscoelastic rheology of the medium around the volcanic conduit and the input to the magma chamber.
Colimaite, K3VS4 - a new potassium-vanadium sulfide mineral from the Colima volcano, State of Colima (Mexico)
Ostrooumov, Mikhail;Taran, Yuri;Arellano-Jiménez, María;Ponce, Alfredo;Reyes-Gasga, José;
Revista mexicana de ciencias geológicas , 2009,
Abstract: colimaite, k3vs4, has been discovered in the active fumaroles of the colima volcano crater, mexico. the mineral is named colimaite after the locality, which, at the same time, is the current active volcanic crater and the name of the state of colima (mexico). colimaite is the naturally occurring analog of synthetic k3vs4. the mineral formed as a sublimate from the volcanic gases and is associated with cristobalite, arcanite, thenardite, barite and native gold. colimaite occurs in "hedgehog"-like particles, which contain the needle crystals, up to 50 μm length and 20 μm width. electron microprobe analyses gave s=43.29 %, k=39.36 %, v=17.41 %, na=0.43 %, with the sum of 100.49 (wt.%), as the mean of six measurements, previously tested as discordant outlier-free statistical samples. the empirical formula, calculated on the basis of eight atoms, is (k2.95na0.06) ∑3.01v1.03 s3.97. the idealized formula is k3vs4. the selected area electron diffraction (saed) and x-ray powder diffraction data (cu kα radiation) indicated that the structure of the micro-sized particles correspond to the orthorhombic k3vs4 crystalline phase: space group pnma, with a=9.139 (5), b=10.625 (7), c=9.135 (3) ?, v=887.03 (9) ?3, and z=4. the five strongest calculated diffraction lines from this natural compound are [d in ?, (i) (hkl)]: 2.806 (100)(230), 3.463 (73)(220), 2.785 (70)( 113), 2.928 (67)(013), and 2.677 (63)(132). saed patterns are quite similar to those of the synthetic k3vs4. the calculated density (z=4) is 2.235 g cm-3. the main observed raman bands lie in the region below 500 cm-1 and the most characteristic bands occur between 150 and 300 cm-1: 192, 203, 245, 264, 277 and 297 cm-1. colimaite, k3vs4, is the first newly recognized mineral species collected from an active fumarole in this volcanic crater. the mineral and the mineral name have been approved by the commission on new minerals, nomenclature and classification (cnmnc) of the international mineralogical association (ima # 200
The Zitácuaro Volcanic Complex, Michoacán, Mexico: magmatic and eruptive history of a resurgent caldera
L. Capra,J. L. Macías,V. H. Gardu?o
Geofísica internacional , 1997,
Abstract: The Zitácuaro Volcanic Complex (ZVC) rises on a basement of metamorphic rocks of Late Jurassic-Early Cretaceous age, and volcanic rocks, limestones, and red beds of Cretaceous age. Volcanic activity related to the Trans-Mexican Volcanic Belt started during Early Miocene with the eruption of calc-alkaline andesites that formed a primitive stratovol cano covering an area about 30 km x 15 km. A major change in eruptive style occurred during Middle Miocene, when a caldera structure formed, "Las Tres Chicas Caldera", approximately 30 km in diameter and dated about 12 Ma. Post-caldera activity consisted of three eruptive episodes of intra-caldera dome resurgence around 12 Ma, 5 Ma, and 0.5 Ma. Each episode featured the intrusion of dacitic central domes, the generation of pyroclastic flows and peri-caldera andesitic lava flows. The activity at the ZVC features recurrent volcanic episodes, the most recent one with emplacement of young resurgent domes such as Cacique. Local seismic activity in the area felt at Zitácuaro, is persistent. The ZVC should be considered as a potentially active volcanic zone.
Tectono Magmatic Types of Volcanic Rocks in the Yangla Ore District,Western Yunnan

WEI Jun-qi,CHEN Kai-xu,HE Long-qing,

地球学报 , 1999,
Abstract: In the Yangla ore district, the volcanic rocks were formed in the central part of Jinshajiang rift-oceanic basin.There are three kinds of tectono-magmatic types:Early Carboniferous enrichment mid-ocean ridge tholeiitic basalts (E-MORB) of Yangla Formation Complex,Late Carboniferous ocean-island calc-alkalic andesite(OIA )and ocean_island alkalic basalts(OIB) of Linong Formation Complex. OIA was produced by crystallization differtiation of OIB and E-MORB mixed magma,and part of E-MORB was formed by mass and energy exchange of OIB and N-MORB.The formation of tectono-magmatic types was related to the mantle plume.
Albinism in Sailfish (Istiophorus platypterus) Found in the Coast of Colima, Mexico  [PDF]
Ana Luisa Vidaurri-Sotelo,Rene Macias-Zamora,Manuel Gallardo Cabello
Pakistan Journal of Biological Sciences , 2005,
Abstract: An albino sailfish (Istiophorus platypterus), with 224 cm of total length was captured with a longline, 35 miles off Punta Campos, Colima, Mexico. This is the first albinism case reported for sailfish in the coasts of Mexico.
Upper cretaceous magmatic suites of the Timok magmatic complex
Banje?evi? Miodrag
Geolo?ki Anali Balkanskog Poluostrva , 2010, DOI: 10.2298/gabp1071013b
Abstract: The Upper Cretaceous Timok Magmatic Complex (TMC) developed on a continental crust composed of different types of Proterozoic to Lower Cretaceous rocks. The TMC consists of the magmatic suites: Timok andesite (AT) - Turonian-Santonian, Metovnica epiclastite (EM) - Coniacian-Campanian, Osni basaltic andesite (AO) and Je evica andesite (AJ) - Santonian-Campanian, Valja Str plutonite (PVS) - Campanian and Boljevac latite (LB). The sedimentary processes and volcanic activity of the TMC lasted nearly continuously throughout nearly the whole Late Cretaceous. The sedimentation lasted from the Albian to the Maastrichtian and the magmatism lasted for 10 million years, from the Upper Turonian to the Upper Campanian. The volcanic front migrated from East to West. The volcanic processes were characterized by the domination of extrusive volcanic facies, a great amount of volcanic material, a change in the depositional environment during the volcanic cycle, sharp facial transitions and a huge deposition of syn- and post-eruptive resedimented volcaniclastics.
Nueva especie de Pseudotelegeusis (Coleoptera: Telegeusidae) del estado de Colima, México
Zaragoza-Caballero, Santiago;
Revista mexicana de biodiversidad , 2008,
Abstract: pseudotelegeusis jiliotupaensis n. sp., is described. the specimen was collected in colima, mexico. this species represents the first record of the genus for mexico and is the third one described for the pseudotelegeusis. a table characterizing the three species is added.
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