The Pliocene Xoconostle high sulfidation epithermal deposit in the Trans-Mexican Volcanic Belt: Preliminary study

The Xoconostle prospect in northeastern Michoacán state, south-central Mexico, is constituted by high sulfidation epithermal breccias and stockworks with Au and Hg prospective anomalies. The mineralization is hosted by latest Miocene to Pliocene rocks grouped into the El Terrero ignimbrite and the Siete Cruces dome complex and a stock of intermediate composition and undetermined (Pliocene?) age. Two alunite samples from deep hypogene advanced argillic alteration assemblages within the deposit yielded 40Ar/39Ar ages at 5.57 ± 0.44 (Messinian) and 3.67 ± 0.20 Ma (Zanclean). Such ages are in good agreement with those of volcanic rocks at a semi-regional scale, especially those associated with the nearby Amealco caldera. Assuming that the formation of Xoconostle deposit could be genetically related to any of the eruptive units in this caldera, it would be associated with dacitic-andesitic rocks at ~4.7 Ma or with bimodal andesite-basalt volcanism at ~3.7 Ma, with which rhyolites at the southwest rim of the caldera (nearer to the epithermal deposit) are contemporaneous. The obtained ages are also in good agreement with those determined for the youngest stages in the evolution of the Trans-Mexican Volcanic Belt (TMVB). In addition, such ages compare well with those established for the E-W striking Morelia-Acambay normal fault zone (or Acambay graben). The occurrence of E-W structural features in the study area support their correlation with those in the Acambay graben. Although the metallogenesis of the TMVB needs further endeavours that contribute to its understanding, the Xoconostle prospect adds up to other dated magmatic-hydrothermal deposits that may collectively constitute a Pliocene metallogenic province whose inception was geologically circumscribed to this volcanic arc. However, this and its companion papers in this issue confirm the metallogenic potential of the TMVB in most of its stages of evolution, particularly in the late Miocene-Pliocene stage of acid and bimodal volcanism.

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The Miocene Tatatila–Las Minas IOCG skarn deposits (Veracruz) as a result of adakitic magmatism in the Trans-Mexican Volcanic Belt

Boletín de la Sociedad Geológica Mexicana ◽

10.18268/bsgm2020v72n3a110520 ◽

2020 ◽

Vol 72 (3) ◽

Author(s):

Edith Fuentes-Guzmán ◽

Eduardo González-Partida ◽

Antoni CamprubÍ ◽

Geovanny Hernández-Avilés ◽

Janet Gabites ◽

...

Keyword(s):

Crustal Contamination ◽

Volcanic Belt ◽

High Potassium ◽

Metallogenic Province ◽

Mexican Volcanic Belt ◽

Intrusive Rocks ◽

Magmatic Stage ◽

Skarn Deposits ◽

Trans Mexican Volcanic Belt ◽

Associated Variety

The Cu- and Au-rich Tatatila–Las Minas IOCG skarn deposits in Veracruz (central-east Mexico) are circumscribed to the earliest stages of the Trans-Mexican Volcanic Belt (TMVB) and stand for a metallogenic province directly linked to its tectonomagmatic dynamics. This is the first well-documented case for such metallogenic province. These deposits were formed as skarns between rocks of the Mesozoic carbonate series and Miocene intermediate to acid hypabyssal rocks. New U-Pb zircon and 40Ar/39Ar ages provide evidence for four epochs of magmatic activity in the area: (1) early Permian (Artinskian), in association with the Paleozoic basement, (2) late Oligocene to early Miocene suite of pre-TMVB intrusive rocks, (3) middle to late Miocene suite of early TMVB-related intrusive rocks, and (4) Pliocene intrusive and extrusive rocks of the TMVB, possibly associated with the Los Humeros post-caldera stage. The obtained ages range between 24.60 ± 1.10 and 19.04 ± 0.69 Ma for stage 2, and between 16.34 ± 0.20 and 13.92 ± 0.22 Ma for stage 3. Stage 2 corresponds to a magmatic stage unheard of in the area, until this study. Only stage 3 rocks are associated with the IOCG skarn mineralization, with retrograde stages dated at 12.44 ± 0.09 (chromian muscovite, phyllic association) and 12.18 ± 0.21 Ma (zircon, potassic association). Therefore, the ages of stage-3 intrusive rocks are interpreted to date the formation of the prograde skarn associations (mostly ~15.4 to <14 Ma). The petrogenetic affinity of stage-2 and stage-3 rocks is about the same—the main difference has to do with higher Y and Yb contents in stage-3 rocks (although no affinity with within-plate granites was found), which is suggestive of an interaction of their parental magmas with alkaline magmas that most likely belong to the conterminous and contemporaneous Eastern Mexico Alkaline Province. Petrological indicators (elemental and isotopic) in Cenozoic rocks consistently point to intermediate to acid, metaluminous, I- and S-type rocks that were emplaced in a subduction-related continental arc, within the medium- to high-potassium calc-alkaline series, with high-silica adakitic signatures due associated to deep-sourced magmas that underwent crustal contamination to some degree. The various possible sources for the magmas with adakitic signature in this context can be narrowed down to two of them that are not mutually exclusive: adakitic derived from subducted slab melting and melting-assimilation-storage-homogenization (MASH)-derived adakites. Both sources are, in principle, capable of generating magmas that would eventually produce magmatic-hydrothermal mineralizing systems with an associated variety of ore deposit types, including IOCG. Also, both possible sources for adakites are compatible with the renewed steepening of the subducted slab after a period of flat subduction, for the earliest stage in the evolution of the TMVB.

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Attenuation of modified Mercalli intensity with distance in Mexico

Bulletin of the Seismological Society of America ◽

10.1785/bssa0780061875 ◽

1988 ◽

Vol 78 (6) ◽

pp. 1875-1884

Author(s):

Mario Chávez ◽

Raul Castro

Keyword(s):

Subduction Zone ◽

Tectonic Setting ◽

Volcanic Belt ◽

Historical Earthquakes ◽

Least Square ◽

Attenuation Relations ◽

South Central ◽

Mexican Volcanic Belt ◽

Trans Mexican Volcanic Belt ◽

Fitting In

Abstract Two relations are proposed to predict the attenuation of Modified Mercalli Intensity (I) with distance (D) for Mexican earthquakes, i.e. ln I = B 0 + B 1 ln ( D / D ' ) + B 2 ( D − D ' ) + B 3 ln M s ln I = B 0 + B 1 ( D / D ' ) + B 2 ln ( D − D ' ) + B 3 ln M s Ms is the earthquake surface-wave magnitude, D′ is a distance related to the maximum I mapped for an earthquake, I′ or to Ms. The coefficients Bi, i = 0, 1, 2, 3 were obtained by fitting in a least-square sense the information contained in the intensity maps of 32 events to the relations. Those events were classified in three groups according to their epicentral location, focal mechanism, and depth, i.e., events related to the subduction-zone intermediate-depth earthquakes in south-central Mexico and to shallow crustal events along the Trans-Mexican Volcanic Belt. The I predicted by the proposed relations compare well with the I observed for historical earthquakes not included in the fitting. Results obtained from a parametrical study showed that the attenuation of I with D is different for each of the three types of earthquakes. For distances of less than about 200 km, the earthquakes associated with the subduction zone have a larger attenuation than the ones originating in the south-central region of Mexico; for greater distances (D > 200 km), the opposite behavior is observed. The events located in the Trans-Mexican Volcanic Belt have a larger attenuation with distance than that of events in the other two regions. From these results, it seems advisable in Mexico to use several attenuation relations to estimate the seismic hazard at a site, depending on the particular tectonic setting and the path of the events under consideration.

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Geochemical Evidence for Slab Melting in the Trans-Mexican Volcanic Belt

Journal of Petrology ◽

10.1093/petrology/egl071 ◽

2006 ◽

Vol 48 (3) ◽

pp. 537-562 ◽

Cited By ~ 90

Author(s):

A. Gomez-Tuena ◽

C. H. Langmuir ◽

S. L. Goldstein ◽

S. M. Straub ◽

F. Ortega-Gutierrez

Keyword(s):

Volcanic Belt ◽

Slab Melting ◽

Geochemical Evidence ◽

Mexican Volcanic Belt ◽

Trans Mexican Volcanic Belt

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Debris avalanches and debris flows transformed from collapses in the Trans-Mexican Volcanic Belt, Mexico – behavior, and implications for hazard assessment

Journal of Volcanology and Geothermal Research ◽

10.1016/s0377-0273(01)00252-9 ◽

2002 ◽

Vol 113 (1-2) ◽

pp. 81-110 ◽

Cited By ~ 107

Author(s):

L Capra ◽

J.L Macı́as ◽

K.M Scott ◽

M Abrams ◽

V.H Garduño-Monroy

Keyword(s):

Hazard Assessment ◽

Debris Flows ◽

Volcanic Belt ◽

Debris Avalanches ◽

Mexican Volcanic Belt ◽

Trans Mexican Volcanic Belt

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Evidence for geomagnetic excursions recorded in Brunhes and Matuyama Chron lavas from the trans-Mexican volcanic belt

Journal of Geophysical Research Solid Earth ◽

10.1002/jgrb.50214 ◽

2013 ◽

Vol 118 (6) ◽

pp. 2648-2669 ◽

Cited By ~ 5

Author(s):

Daniel M. Michalk ◽

Harald N. Böhnel ◽

Norbert R. Nowaczyk ◽

Gerardo J. Aguírre-Diaz ◽

Margarita López-Martínez ◽

...

Keyword(s):

Volcanic Belt ◽

Matuyama Chron ◽

Mexican Volcanic Belt ◽

Trans Mexican Volcanic Belt

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Tertiary arc-magmatism of the Sierra Madre del Sur, Mexico, and its transition to the volcanic activity of the Trans-Mexican Volcanic Belt

Journal of South American Earth Sciences ◽

10.1016/s0895-9811(99)00036-x ◽

1999 ◽

Vol 12 (6) ◽

pp. 513-535 ◽

Cited By ~ 62

Author(s):

D.J Morán-Zenteno ◽

G Tolson ◽

R.G Martı́nez-Serrano ◽

B Martiny ◽

P Schaaf ◽

...

Keyword(s):

Volcanic Activity ◽

Volcanic Belt ◽

Arc Magmatism ◽

Mexican Volcanic Belt ◽

Sierra Madre ◽

Sierra Madre Del Sur ◽

Trans Mexican Volcanic Belt

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Volcano-sedimentary processes at Las Derrumbadas rhyolitic twin domes, Serdán-Oriental basin, Eastern Trans-Mexican Volcanic Belt

Geological Society London Special Publications ◽

10.1144/sp520-2021-144 ◽

2021 ◽

pp. SP520-2021-144

Author(s):

Marie-Noëlle Guilbaud ◽

Corentin Chédeville ◽

Ángel Nahir Molina-Guadarrama ◽

Julio Cesar Pineda-Serrano ◽

Claus Siebe

Keyword(s):

Volcanic Belt ◽

Debris Avalanche ◽

Density Currents ◽

Content Type ◽

Mexican Volcanic Belt ◽

Wide Range ◽

Eruptive Episode ◽

Basin Floor ◽

Supplementary Material ◽

Trans Mexican Volcanic Belt

AbstractThe eruption of the ∼10 km3 rhyolitic Las Derrumbadas twin domes about 2000 yrs ago has generated a wide range of volcano-sedimentary deposits in the Serdán-Oriental lacustrine basin, Trans-Mexican Volcanic Belt. Some of these deposits have been quarried, creating excellent exposures. In this paper we describe the domes and related products and interpret their mode of formation, reconstructing the main phases of the eruption as well as syn-and-post eruptive erosional processes. After an initial phreatomagmatic phase that built a tuff ring, the domes grew as an upheaved plug lifting a thick sedimentary pile from the basin floor. During uplift, the domes collapsed repeatedly to form a first-generation of hetero-lithologic hummocky debris avalanche deposits. Subsequent dome growth produced a thick talus and pyroclastic density currents. Later, the hydrothermally-altered over-steepened dome peaks fell to generate 2nd generation, mono-lithologic avalanches. Subsequently, small domes grew in the collapse scars. From the end of the main eruptive episode onwards, heavy rains remobilized parts of the dome carapaces and talus, depositing lahar aprons. Las Derrumbadas domes are still an important source of sediments in the basin, and ongoing mass-wasting processes are associated with hazards that should be assessed, given their potential impact on nearby populations.Supplementary material at https://doi.org/10.6084/m9.figshare.c.5752296

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Late Cenozoic tectonics offshore western Mexico and its relation to the structure and volcanic activity in the western Trans-Mexican Volcanic Belt

Geofísica Internacional ◽

10.22201/igeof.00167169p.1993.32.4.601 ◽

1993 ◽

Vol 32 (4) ◽

pp. 543-559

Author(s):

Hugo Delgado Granados

Keyword(s):

Volcanic Activity ◽

Volcanic Belt ◽

Late Cenozoic ◽

Western Mexico ◽

Mexican Volcanic Belt ◽

Cenozoic Tectonics ◽

Trans Mexican Volcanic Belt

La tasa de convergencia calculada indica que la tectónica del occidente de México ha sido tensional durante los últimos 3 Ma. Este estilo de deformación se ve reflejado en la formación de estructuras rift en la parte occidental de la Faja Volcánica Trans-Mexicana [FVTM]. Los valores obtenidos para la tasa de convergencia predicen que, a través del tiempo, se verifica una tectónica menos tensional (con tendencia a la neutralidad) en la parte sureste de la zona de interacción de las placas de Rivera Y Norteamérica, mientras que en la parte noroccidental se vuelve más tensional. Por otra parte, un análisis cualitativo de las tasas de esparcimiento muestra que éstas fueron más rápidas antes de los 6.5 Ma de lo que fueron posteriormente. Después de analizar diferentes parámetros cinemáticos, se concluyó que la tasa de esparcimiento de la cresta del Pacífico Oriental en su sector Pacífico-Rivera, influye fuertemente sobre la tasa de convergencia. De esta manera se puede establecer una correlación positiva entre la evolución de la tasa de esparcimiento de la cresta Pacífico-Rivera y la geología continental. Esta correlación muestra que tasas de esparcimiento relativamente rápidas coinciden con la presencia de volcanismo monogenético calci-alcalino en la parte occidental de la FVTM cuando menos desde hace 10 Ma y que este tipo de volcanismo continúa hasta nuestros días. Sin embargo, cuando la tasa de esparcimiento se ha hecho más lenta (y por tanto la tasa de convergencia se ha hecho menor) durante el periodo comprendido entre 6.5 Ma y 3.5 Ma, se ha verificado en la región una tectónica extensional ampliamente distribuida, volcanismo explosivo y sedimentación lacustre en los sistemas rift de Colima, Tepic-Zacoalco y de Chapala; particularmente entre los 4.6 Ma y 3.9 Ma ha coincidido con volcanismo alcalino en los rifts fr Colima y Tepic-Zacoalco. Un leve incremento en la tasa de esparcimiento después de los 3.5 Ma coinciden con el decremento de actividad volcánica (principalmente alcalina). Durante el periodo entre 1.6 Ma y 0.7 Ma, la tasa de esparcimiento disminuyó de nuevo coincidiendo con un fallamiento normal continuo en las tres estructuras rift mencionadas y en parte, con otra etapa de volcanismo alcalino (entre 1.4 Ma y 0.2 Ma) en los rift de Colima y Tepic-Zacoalco. Después de los 0.7 Ma, la tasa de esparcimiento se ha incrementado levemente. Por otra parte, se observa una relación genética entre el contenido de elementos compatibles en rocas volcánicas de la región con la tasa de convergencia, lo cual implica que tasas de subducción mayores aportan una mayor cantidad de sedimentos acrecionados a la cuña del manto. Esto explica las diferencias geoquímicas entre las rocas volcánicas a lo largo del frente volcánico de la parte occidental de la FVTM.

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PRELIMINARY RESULTS OF PALAEOMA GNETIC MEASUREMENTS OF TERTIARY-QUATERNARY IGNEOUS ROCKS FROM THE EASTERN PART OF THE TRANS MEXICAN VOLCANIC BELT

Geofísica Internacional ◽

10.22201/igeof.00167169p.1981.20.3.1088 ◽

1981 ◽

Vol 20 (3) ◽

Author(s):

H. Bohnel ◽

J. F. W. Negendank

Keyword(s):

Volcanic Belt ◽

Igneous Rocks ◽

Preliminary Results ◽

Mexican Volcanic Belt ◽

Trans Mexican Volcanic Belt

Resultados paleomagnéticos de aproximadamente 500 muestras orientadas colectadas en 59 sitios de la sección este del eje volcánico trans-Mexicano se presentan en este trabajo. Las rocas ígeneas estudiadas son del Plioceno y Cuaternario, con la excepción del macizo de Palma Sola, de edad Mioceno. Los resultados paleomagnéticos se usan para correlacionar con resultados geoquímicos y geológicos del área y con resultados paleomagnéticos de Norteamérica y México. Los resultados no indican moviemiento relativo significante entre Norteamérica y la sección central-este de México en el período estudiado.

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