Download or read book Volcanism in the central volcanic zone of the andes written by Felipe Aguilera and published by Frontiers Media SA. This book was released on 2023-05-08 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Volcanoes of the Central Andes written by Shanaka L. De Silva and published by Springer. This book was released on 1991 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Geophysical Survey of Active Volcanism in the Central and Southern Andes written by Jennifer Ann Jay and published by . This book was released on 2014 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: The subduction of the Nazca plate beneath the South American plate results in great earthquakes and active volcanism along the Andean margin. The Central Volcanic Zone (CVZ) between 15°S and 28°S and the Southern Volcanic Zone (SVZ) between 33°S and 46°S are separated by a zone of flat slab subduction and differ significantly in the manifestation of current volcanic activity. The CVZ has been considered less hazardous due to the few number of historical volcanic eruptions compared to the SVZ, yet it contains the largest mid-crustal magma body on Earth and erupted at least 10,000 km3 of ignimbrite in the Late Miocene (10-1 Ma). In this dissertation, I use InSAR (interferometric synthetic aperture radar), thermal remote sensing, and seismology to investigate active volcanism in the Central and Southern Andes. InSAR and thermal remote sensing provide synoptic coverage along the volcanic arc, and seismic experiments allow further examination of selected volcanoes. I establish the first catalog of seismicity at Uturuncu volcano in Bolivia, where InSAR has observed continuous uplift since 1992, and find an unusually high seismicity rate for a Pleistocene volcano as well as swarm activity and triggered earthquakes. I then conduct a survey using satellite thermal infrared data to detect thermal hotspots related to volcanic activity throughout the CVZ and SVZ. I find hotspots at many volcanoes that had not previously been documented, with the CVZ containing more volcanoes with hotspots than the SVZ. One of the most thermally active volcanoes in the SVZ, Cordón Caulle volcano, experienced a large rhyodacitic eruption from 2011-2012. I use InSAR and petrology to model the pre-eruptive conditions at depth and coeruptive processes and find that a large, long-lived crustal magma reservoir must be present beneath Cordón Caulle. Finally, I carry out an InSAR survey of volcanoes in southern Peru, completing a regional study of volcano deformation in the CVZ and allowing for a comprehensive comparative analysis between the CVZ and SVZ.
Download or read book Textures Structures and Processes of Volcanic Successions written by Beatriz L.L. Coira and published by Springer Nature. This book was released on 2020-09-18 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a complete study of the Central Andean volcanism and its most distinctive features, from the lower Paleozoic to the Cenozoic times in the framework of its processes, eruptive mechanisms and geodynamic conditions. It helps readers understand the nature of the volcanic geology and the volcaniclastic related deposits linked to the evolution of the Andean continental margin. Special attention is paid to the analysis of the ancient volcanic successions and the difficulties in recognition of the original rock type caused by the effects of deformation, metamorphism and alteration. The authors use distinctive cases to describe how to apply different tools in analysis and interpretation. The selected representative, well exposed and preserved volcanic records of the Southern Central Andes analyzed in this book open new perspectives in the understanding of the volcanic processes linked to active continental margins as the Central Andes. This book will be of special interest to volcanologists and specialists in the earth sciences and appeal to both undergraduate and graduate students in geology.
Download or read book An Overview of the Mafic and Felsic Monogenetic Neogene to Quaternary Volcanism in the Central Andes Northern Chile 18 28 Lat S written by Gabriel Ureta and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monogenetic volcanism produces small eruptive volumes with short eruption history, different chemical compositions, and relatively simple conduit. The Central Volcanic Zone of the Andes is internationally known as a natural laboratory to study volcanism, where mafic and felsic products are present. In this contribution, the spectrum of architectures, range of eruptive styles, lithological features, and different magmatic processes of the mafic and felsic monogenetic Neogene to Quaternary volcanoes from the Central Volcanic Zone of the Andes in northern Chile (18°S-28°S) are described. The major volcanic activity occurred during the Pleistocene, where the most abundant activity corresponds to effusive and Strombolian eruptions. This volcanism is characterized by external (e.g., magma reservoirs or groundwater availability) and internal (e.g., magma ascent rate or interaction en-route to the surface) conditions, which determine the changes in eruptive style, lithofacies, and magmatic processes involved in the formation of monogenetic volcanoes.
Download or read book Volcanoes of the Central Andes written by Shanaka L. DeSilva and published by Springer. This book was released on 1991-07-22 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: With sharp satellite images, detailed figures and a highly competent description of each registered volcano, this catalog is invaluable for all earth scientists working in the Andes. Detailed descriptions of 44 major, potentially active volcanoes form the core of the book. A compendium of geographical and morphological data is followed by a summary of the structural and volcanological evolution
Download or read book Large Volume Explosive Silicic Volcanism in the Central Andes of Northern Chile written by S. L. De Silva and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Textures Structures and Processes of Volcanic Successions written by Beatriz L.L. Coira and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a complete study of the Central Andean volcanism and its most distinctive features, from the lower Paleozoic to the Cenozoic times in the framework of its processes, eruptive mechanisms and geodynamic conditions. It helps readers understand the nature of the volcanic geology and the volcaniclastic related deposits linked to the evolution of the Andean continental margin. Special attention is paid to the analysis of the ancient volcanic successions and the difficulties in recognition of the original rock type caused by the effects of deformation, metamorphism and alteration. The authors use distinctive cases to describe how to apply different tools in analysis and interpretation. The selected representative, well exposed and preserved volcanic records of the Southern Central Andes analyzed in this book open new perspectives in the understanding of the volcanic processes linked to active continental margins as the Central Andes. This book will be of special interest to volcanologists and specialists in the earth sciences and appeal to both undergraduate and graduate students in geology.
Download or read book Andean Magmatism and Its Tectonic Setting written by Russell S. Harmon and published by Geological Society of America. This book was released on 1991 with total page 319 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution of an Andean Margin written by Suzanne Mahlburg Kay and published by Geological Society of America. This book was released on 2006-01-01 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The objective of this volume is to examine the Cenozoic tectonic and magmatic evolution from the arc to the retroarc of a distinctive end-member of the Andean accretionary orogen between 35*S and 39*S. The evolution of the Andes in this region provides an outstanding case study of an orogen where periods of contraction and extension, crustal shortening and normal faulting, and differences in retroarc volcanism reflect a tectonic regime that alternates in space and time. Structural, magmatic, and paleogeographic patterns correlate strongly with the dynamics of the subduction zone. The region includes the Neuquen basin which is one of the most prolific of the Central Andes. The tectonic setting is important in understanding hydrocarbon systems of the sub-Andean basin and the potential for ore deposits in the cordillera. The book is fundamental for researchers working on tectonics and magmatism in Andean type systems as well as those involved in exploration."--Publisher's website.
Download or read book Tectonics of the Southern Central Andes written by Klaus-Joachim Reutter and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: together with contributions by invited geoscientists The Central Andes, whose orogenic activity is so impressively documented by recent volcanism and and counterparts from other countries, during a workshop held in Berlin, 23-25 May 1990. A great earthquakes, have always attracted the attention of geoscientists. This interest became even more accen number of the papers presented at this workshop are tuated since, a quarter of a century ago, Plate included in this volume. While most of the chapters Tectonics became the basis for the New Global refer regionally to the segment of the southern Andes Tectonics concept, in which this huge mountain range mentioned above, others treat general aspects or deal was the most spectacular example of an active conti with Andean regions farther south, thus showing not only that the structures of this mountain range can be nental margin. Thus, in addition to the continuing research work by South American and foreign geo followed to more distant parts but also that there are scientists dedicated mostly to regional and economic significant structural variations along strike. problems, a great number of special research pro Like other books which originate from workshops grammes were initiated aiming at a better understand and are comprised of contributions from many ing of the processes acting at a convergent plate authors, also this one cannot give a complete and margin. well-balanced view of the scientific subject dealt In 1982, the earth science institutes of the Freie with, in this case the southern Central Andes.
Download or read book Unraveling the Magmatic and Geomorphic Processes Recorded in the Topography of the Central Andes written by and published by . This book was released on 2015 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: The topography of volcanic arcs reflects a combination of magmatic ascent processes that deform the overlying crust, volcanic eruptions that blanket the surface in lava and ash, and geomorphic processes that shape these deposits into the observable landscape and consequently record an erosional archive of surface deformation. A central goal of geomorphology is to utilize the form of landscapes to infer the processes that shape them, yet comparatively little work has been done to quantitatively understand the geomorphology of volcanic landscapes. The Central Volcanic Zone of the South American Andes (CVZ, 15-28°S) represents an ideal location for understanding the processes that shape the surface of volcanic arcs; the arid climate and well-constrained geochronology of volcanic deposits provide a geomorphic archive going back 11 Myrs, and the wealth of available geophysical imaging data provides a high-resolution glimpse into the subsurface. In this thesis I utilize geormophic and geophysical data to explore fundamental questions in volcanic landscape evolution at varying spatial scales. To begin, I examine the isostatic uplift response to crustal intrusion of mantle-derived melt, resulting in growth of the largest known active magma reservoir on Earth (the Altiplano-Puna Magma Body). From topography I show that it is possible to calculate the contribution of mantle-derived melt to crustal thickening, and I compare these results to independent seismic estimates that agree well with our data. I then use the record of volcanic deposits from the Altiplano-Puna Magma Body to estimate the flux of mantle melt into the crust, and show that predicted uplift rates are comparable to the surface uplift associated with convective lithospheric removal. Next, I explore how the topography of individual volcanic systems can help discern the style of melt ascent from deeper crustal magma reservoirs to shallow ones. Using two actively deforming volcanoes in the CVZ, Uturuncu volcano and the Lazufre volcanic complex, I use river profiles, lake shorelines, and lava flow deflections to infer each volcano's surface deformation record into the geomorphic past. Uturuncu volcano shows little signs of permanent paleo-deformation, suggesting transient ascent of magma over millenial timescales, while Lazufre's long wavelength deformation suggests continued accumulation of magma since > 0.3 Ma. Finally, I utilize the unique topography of a windswept ignimbrite erupted from the Altiplano-Puna Magma body to better understand how wind abrasion can incise bedrock canyons, a fundamental geomorphic process in arid landscapes on both Earth and Mars. Using a natural experiment within the 4 Ma Puripicar ignimbrite on the western slope of the Central Andes, we quantify the relative contribution of wind and water erosion in propagating bedrock canyons and show that wind can incise canyons an order of magnitude faster than rivers, streamlining their profiles in the process. Thus, in these chapters I illustrate how geomorphology can be a useful tool for quantifying subsurface magmatic processes, while volcanic landscapes themselves can also provide unique opportunities for understanding fundamental planetary geomorphic processes not often observed elsewhere on Earth.
Download or read book Spatial Analysis of Volcanoes in the Central Andes written by Shubhada Satish Savant and published by . This book was released on 2005 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantifying the Properties of Magmatic Intrusions in the Central Andes with Geodesy written by Scott Thomas Henderson and published by . This book was released on 2015 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volcanism in convergent arcs is the end result of magma ascending to the Earth's surface. However, many of the details of the ascent process are still debated. In particular, how long does magma persist in reservoirs at particular depths? What is the timescale and physical mechanism of ascent between reservoirs? To address these questions this thesis investigates volcanic deformation in the Central Andes Volcanic Zone of South America (CVZ, 15-28? S). The CVZ is one of three distinct volcanic arc segments in the Andes that results from the subduction of the Nazca Plate beneath the South America Plate. To begin, I compile available information for Holocene eruptions to show that despite containing the largest number of 'active volcanoes' (70), the CVZ has only 12% of recorded eruptions in the Andes. I then demonstrate through a synoptic survey with Interferometric Synthetic Aperture Radar (InSAR) that 40% of volcanic deformation events in the Andes over the last two decades occur in the CVZ. Next, I attempt to constrain the physical properties of two active intrusions in the CVZ that are unique in terms of their large size (>50km diameter) and persistent maximum rates of uplift (>1 cm/yr for>10yrs). First, I focus on Uturuncu Volcano, where I analyze InSAR and GPS data to constrain the spatial and temporal deformation pattern between 1992 and 2014. I propose a 'dipole' model of magma transport between vertically-aligned reservoirs in the lower crust and middle crust to explain the observation of uplift and peripheral subsidence at Uturuncu. The ratio of vertical to radial surface displacements for single inflation source is increased by adding a dipole reservoir, but decreased to a greater degree by crustal heterogeneity known from seismic tomography. Additionally, volume discrepancies of 1-10x between source and sink reservoirs are expected given known ranges of lower crustal material properties in the Central Andes. Finally, I present current InSAR and GPS observations at Lazufre Volcanic Complex through 10/2014 that show maintained spatial and temporal patterns of uplift compared to the previous two decades. Using a finite element model for an opening sill I demonstrate the role of layering and 3D heterogeneous structure based on newly-available seismic tomography. The proposed heterogeneous structure increases the surface displacements for homogeneous crust by less than 7% within a 10km radius of the center of uplift.
Download or read book Volcanology and Petrology of Volc n Mi o Andean Central Volcanic Zone written by Claire M. McKee and published by . This book was released on 2001 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Convergent Margin Magmatism in the Central Andes and Its Near Antipodes in Western Indonesia written by Morgan J. Salisbury and published by . This book was released on 2011 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation combines volcanological research of three convergent continental margins. Chapters 1 and 5 are general introductions and conclusions, respectively. Chapter 2 examines the spatiotemporal development of the Altiplano-Puna volcanic complex in the Lipez region of southwest Bolivia, a locus of a major Neogene ignimbrite flare- up, yet the least studied portion of the Altiplano-Puna volcanic complex of the Central Andes. New mapping and laser-fusion 40Ar/39Ar dating of sanidine and biotite from 56 locations, coupled with paleomagnetic data, refine the timing and volumes of ignimbrite emplacement in Bolivia and northern Chile to reveal that monotonous intermediate volcanism was prodigious and episodic throughout the complex. 40Ar/39Ar age determinations of 13 ignimbrites from northern Chile previously dated by the K-Ar method improve the overall temporal resolution of Altiplano-Puna volcanic complex development. Together with new and updated volume estimates, the new age determinations demonstrate a distinct onset of Altiplano-Puna volcanic complex ignimbrite volcanism with modest output rates beginning ~11 Ma, an episodic middle phase with the highest eruption rates between 8 and 3 Ma, followed by a general decline in volcanic output. The cyclic nature of individual caldera complexes and the spatiotemporal pattern of the volcanic field as a whole are consistent with both incremental construction of plutons as well as a composite Cordilleran batholith. Chapter 3 examines the spatiotemporal development of marine tephra deposits in deep sea sediment cores from the Sunda trench near Sumatra, which reveal evidence for seven large (minimum volume 0.6 - 6.3 km3), previously undocumented, explosive eruptions in this region over the last ~110,000 years, presumably sourced from mainland Sumatra. Sediment cores were collected within and adjacent to the Sunda trench from 3.3°N to 4.6°S at water depths between 1.8 and 5.5 km and distances of ~200 to 310 km from the active Sumatran volcanic arc. Glass shards within the tephra horizons were analyzed via the electron microprobe and laser ablation ICP-MS and define three compositional groups. Minimum volume estimates for the seven unique units are consistent with volcanic explosivity index (VEI; Newhall and Self, 1982) values of 4 - 5. The most frequent, widespread, and youngest deposits were found in the central region of the study area suggesting the central Sumatran arc as at the highest risk for large explosive eruptions. The first detailed chronological and geochemical data are presented for Tunupa volcano and nearby Huayrana lavas in chapter 4. New 40Ar/39Ar age determinations reveal edifice construction at ~1.5 Ma, a duration of ~90-240 k.y., and extrusion rates of 0.43 to 0.93 km3/k.y. Mineralogical compositional and textural data are consistent with shallow crustal storage (~7-18 km) and magma mixing. Volcano morphology, extrusion rates, mineralogy and textures are all similar to the Pleistocene to recent composite cones of the arc front, although new and available age data from the literature indicate that Western Cordilleran volcanism was concomitant with extrusion of both Huayrana (~11 Ma) and Tunupa (~1.5 Ma) lavas in the behind arc region. Arc-related volcanism was either widespread during these eruptive periods, or an additional melting mechanism was involved. Geochemical data, such as lower Ba/Nb ratios and enriched high field strength elemental concentrations, compared to volcanoes of the modern arc front suggest that Huayrana and Tunupa lavas were derived from a different source than the modern arc front. Geophysical and geochemical research in the central Andes indicate local variations in crustal and lithospheric thicknesses and compositions consistent with a dynamic continental lithosphere that has foundered in piecemeal fashion into the underlying asthenosphere throughout the mid to late Cenozoic. The data presented in this chapter for Tunupa and Huayrana indicate a complex petrogenetic origin and more research is necessary to determine the relative roles of arc and non-arc volcanism beneath the central Altiplano.
Download or read book Monogenetic Volcanism written by K. Németh and published by Geological Society of London. This book was released on 2017-06-20 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nature and origin of the small-scale volcanic systems, generally referred to as 'monogenetic', have enjoyed an elevated level of interest during the past decade. There has been recognition that their ostensibly simple volcano types are a window into the nature of explosive volcanism, landscape evolution and the processes of magma generation in the Earth’s upper mantle. In the past few years, major conferences have offered specialized technical sessions dealing with monogenetic volcanism and there have been thematic conferences, such as the IAVCEI International Maar Conference series, which have provided a focus for discussion of volcanological and geochemical aspects of small-scale basaltic volcanism. Many new aspects of monogenetic volcanism have emerged and have clearly demonstrated that this volcanism can be very complex on a fine scale. This book is a collection of papers arising from two recent Maar Conferences (the fifth in Queretaro Mexico and the sixth in Changchun, China) and serves as a snapshot of current research on monogenetic volcanism.
