Evolution of a magmatic to a phreatomagmatic volcanic system: The birth of a monogenetic volcanic field, Tilocálar volcanoes, northern Chile

2021 ◽  
pp. 107243
Author(s):  
Gabriel Ureta ◽  
Károly Németh ◽  
Felipe Aguilera ◽  
Szabolcs Kósik ◽  
Rodrigo González ◽  
...  
Keyword(s):  
Volcanic Field ◽  
Northern Chile ◽  
Volcanic System ◽  
Monogenetic Volcanic Field

Eruptive frequency of the Bora-Baricha-Tullu Moye (BBTM) volcanic system in the Central Main Ethiopian Rift

2021 ◽  
Author(s):  
Amdemichael Zafu Tadesse ◽  
Karen Fontijn ◽  
Abate Assen Melaku ◽  
Ermias Filfilu Gebru ◽  
Victoria Smith ◽  
...  
Keyword(s):  
Late Quaternary ◽  
Volcanic Eruptions ◽  
Volcanic Field ◽  
Tectonic Activity ◽  
Explosive Eruptions ◽  
Ethiopian Rift ◽  
Rift System ◽  
Diagnostic Features ◽  
Volcanic System ◽  
Main Ethiopian Rift

<p>The Main Ethiopian Rift (MER) is the northern portion of the East African Rift System and separates the Eastern and Western plateaus of Ethiopia. The recent volcanic and tectonic activity is largely focused within the rift basin along a 20 km wide zone on the rift floor. Large silicic volcanic complexes are aligned along this central rift axis but their eruptive histories are not well constrained.</p><p>The Bora-Baricha-Tullu Moye (BBTM) volcanic field is situated in the central Main Ethiopian Rift and has a different appearance than the other MER volcanic systems. The BBTM constitutes several late Quaternary edifices, the major ones are: Tullu Moye, Bora and Baricha. In addition, there are multiple smaller eruptive vents (e.g. Oda and Dima), cones, and domes across the ca. 20 X 20 km wide area. Currently, there is very little information on the frequency and magnitude of past volcanic eruptions. We present a new dataset of field observations, componentry, petrography, geochronology (<sup>40</sup>Ar/<sup>39</sup>Ar), and glass major and trace element chemistry. The data are assessed as potential fingerprints to assign diagnostic features and correlate units across the area, and establish a tephrostratigraphic framework for the BBTM volcanic field.</p><p>Two large-volume and presumably caldera-forming eruptions are identified, the younger of which took place at 100 ka. The volcanic products exposed in the BBTM area show that the volcanic field has undergone at least 20 explosive eruptions since then. The post-caldera eruptions have comenditic (Tullu Moye) and pantelleretic (Bora and Baricha) magma compositions. Other smaller edifices such as Oda and Dima also erupted pantelleritic magmas, and only differ slightly in composition than tephra of Bora and Baricha. Tullu Moye had two distinct explosive eruptions that dispersed tephra up to 14 km away and on to the eastern plateau. Bora and Baricha together had at least 8 explosive eruptions. Their deposits can be distinguished by their light grey color and unique lithic components. Oda had 7 eruptions, the most recent of which generated a pyroclastic density current that travelled up to 10 km away from the vent. Dima experienced at least 3 eruptions, generating tephra with a bluish-grey colour.</p><p>This mapping and compositional analysis of the deposits from the BBTM in the MER indicates that the region has been more active in the last 100 ka than previously thought, which has implications for hazards assessments for the region.</p>

scholarly journals Aging of basalt volcanic systems and decreasing CO<sub>2</sub> consumption by weathering

2019 ◽  
Vol 7 (1) ◽  
pp. 191-197 ◽  
Author(s):  
Janine Börker ◽  
Jens Hartmann ◽  
Gibran Romero-Mujalli ◽  
Gaojun Li
Keyword(s):  
Age Distribution ◽  
Aging Effect ◽  
Hydrothermal Activity ◽  
Volcanic Field ◽  
Critical Zone ◽  
Volcanic System ◽  
Reactive Material ◽  
Volcanic Fields ◽  
Basalt Weathering ◽  
Aging Function

Abstract. Basalt weathering is one of many relevant processes balancing the global carbon cycle via land–ocean alkalinity fluxes. The CO2 consumption by weathering can be calculated using alkalinity and is often scaled with runoff and/or temperature. Here, it is tested if the surface age distribution of a volcanic system derived by geological maps is a useful proxy for changes in alkalinity production with time. A linear relationship between temperature normalized alkalinity fluxes and the Holocene area fraction of a volcanic field was identified using information from 33 basalt volcanic fields, with an r2=0.93. This relationship is interpreted as an aging function and suggests that fluxes from Holocene areas are ∼10 times higher than those from old inactive volcanic fields. However, the cause for the decrease with time is probably a combination of effects, including a decrease in alkalinity production from material in the shallow critical zone as well as a decline in hydrothermal activity and magmatic CO2 contribution. The addition of fresh reactive material on top of the critical zone has an effect in young active volcanic settings which should be accounted for, too. A comparison with global models suggests that global alkalinity fluxes considering Holocene basalt areas are ∼60 % higher than the average from these models imply. The contribution of Holocene areas to the global basalt alkalinity fluxes is today however only ∼5 %, because identified, mapped Holocene basalt areas cover only ∼1 % of the existing basalt areas. The large trap basalt proportion on the global basalt areas today reduces the relevance of the aging effect. However, the aging effect might be a relevant process during periods of globally intensive volcanic activity, which remains to be tested.

scholarly journals Structural controls on the location, geometry and longevity of an intraplate volcanic system: the Tuatara Volcanic Field, Great South Basin, New Zealand

2020 ◽  
Vol 177 (5) ◽  
pp. 1039-1056
Author(s):  
Thomas B. Phillips ◽  
Craig Magee
Keyword(s):  
Volcanic Field ◽  
Auckland Volcanic Field ◽  
Seismic Section ◽  
Volcanic System ◽  
Seismic Reflection Data ◽  
Content Type ◽  
Reflection Data ◽  
3D Geometry ◽  
Plumbing Systems ◽  
Supplementary Material

Intraplate volcanism is widely distributed across the continents, but the controls on the 3D geometry and longevity of individual volcanic systems remain poorly understood. Geophysical data provide insights into magma plumbing systems, but, as a result of the relatively low resolution of these techniques, it is difficult to evaluate how magma transits highly heterogeneous continental interiors. We use borehole-constrained 2D seismic reflection data to characterize the 3D geometry of the Tuatara Volcanic Field located offshore New Zealand's South Island and investigate its relationship with the pre-existing structure. This c. 270 km2 field is dominated by a dome-shaped lava edifice, surrounded and overlain by c. 69 volcanoes and >70 sills emplaced over 40 myr from the Late Cretaceous to Early Eocene (c. 85–45 Ma). The Tuatara Volcanic Field is located above a basement terrane boundary represented by the Livingstone Fault; the recently active Auckland Volcanic Field is similarly located along-strike on North Island. We suggest that the Livingstone Fault controlled the location of the Tuatara Volcanic Field by producing relief at the base of the lithosphere, thereby focussing lithospheric detachment over c. 40 myr, and provided a pathway that facilitated the ascent of magma. We highlight how observations from ancient intraplate volcanic systems may inform our understanding of active intraplate volcanic systems, including the Auckland Volcanic Field.Supplementary material: Interpreted seismic section showing well control on stratigraphic interpretation is available at https://doi.org/10.6084/m9.figshare.c.5004464

Timing the evolution of a monogenetic volcanic field: Sierra Chichinautzin, Central Mexico

2018 ◽  
Vol 356 ◽  
pp. 225-242 ◽  
Author(s):  
M.C. Jaimes-Viera ◽  
A.L. Martin Del Pozzo ◽  
P.W. Layer ◽  
J.A. Benowitz ◽  
A. Nieto-Torres
Keyword(s):  
Volcanic Field ◽  
Central Mexico ◽  
Monogenetic Volcanic Field

Plio-pleistocene paleomagnetic record from the Michoacán-Guanajuato Monogenetic Volcanic Field (Western Mexico)

2011 ◽  
Vol 55 (2) ◽  
pp. 311-328 ◽  
Author(s):  
Rafael Maciel Peña ◽  
Avto Goguitchaichvili ◽  
Bernard Henry ◽  
Leda Sánchez-Bettucci ◽  
Juan Morales ◽  
...  
Keyword(s):  
Volcanic Field ◽  
Western Mexico ◽  
Monogenetic Volcanic Field

scholarly journals Stratigraphy of Architectural Elements of a Buried Monogenetic Volcanic System

2019 ◽  
Vol 11 (1) ◽  
pp. 581-616 ◽  
Author(s):  
Alan Bischoff ◽  
Andrew Nicol ◽  
Jim Cole ◽  
Darren Gravley
Keyword(s):  
Geothermal Energy ◽  
Sedimentary Basin ◽  
Sedimentary Basins ◽  
Volcanic Field ◽  
Plumbing System ◽  
Volcanic System ◽  
Architectural Elements ◽  
Stratigraphic Framework ◽  
Cone Type ◽  
Geological Evolution

Abstract Large volumes of magma emplaced and deposited within sedimentary basins can have an impact on the architecture and geological evolution of these basins. Over the last decade, continuous improvement in techniques such as seismic volcano-stratigraphy and 3D visualisation of igneous bodies has helped increase knowledge about the architecture of volcanic systems buried in sedimentary basins. Here, we present the complete architecture of the Maahunui Volcanic System (MVS), a middle Miocene monogenetic volcanic field now buried in the offshore Canterbury Basin, South Island of New Zealand. We show the location, geometry, size, and stratigraphic relationships between 25 main intrusive, extrusive and sedimentary architectural elements, in a comprehensive volcano-stratigraphic framework that explains the evolution of the MVS from emplacement to complete burial in the host sedimentary basin. Understanding the relationships between these diverse architectural elements allows us to reconstruct the complete architecture of the MVS, including its shallow (<3 km) plumbing system, the morphology of the volcanoes, and their impact in the host sedimentary basin during their burial. The plumbing system of the MVS comprises saucer-shaped sills, dikes and sill swarms, minor stocks and laccoliths, and pre-eruptive strata deformed by intrusions. The eruptive and associated sedimentary architectural elements define the morphology of volcanoes in the MVS, which comprise deep-water equivalents of crater and cone-type volcanoes. After volcanism ceased, the process of degradation and burial of volcanic edifices formed sedimentary architectural elements such as inter-cone plains, epiclastic plumes, and canyons. Insights from the architecture of the MVS can be used to explore for natural resources such as hydrocarbons, geothermal energy and minerals in buried and active volcanic systems elsewhere.

Sign in / Sign up

Export Citation Format

Share Document