The following sessions may be of interest to the InterRidge community at the Goldschmit Conference (https://goldschmidt.info/2020/) in Honolulu, Hawai'i, 21-26 June 2020. Please submit your abstracts before the deadline of 14 February 2020 (23:59 HST).
Please feel free to contact the IR Coordinator to advertise any other session of interest to the IR community.
Session 03b: South Atlantic Evolution
Keynote: Peter Bunge (Univ. Munich)
The understanding of the tectonic evolution of the oceanic lithosphere needs new approaches about different geotectonic context such as oceanic plateaus, aseismic ridges, microplates, seamount chains evolution, continental crust fragments, continental margins, exhumation and other models. In this context, the evolution of the South Atlantic Ocean provides an important evidence regarding a complex evolution since break up process starting during the Mesozoic until the Quaternary subsiding, uplift and horizontal processes. The Walvis Ridge-Rio Grande Rise system has been more or less continuously active since the late Cretaceous, links continental flood basalt province (Etendeka in Africa and Paraná in Brazil) with active hotspot (Tristan-Gough) . On the basis of geological data, parts of the region appear to have been constructed by much younger Eocene volcanism. Results coming from geophysical, geological and petrological research are refreashing concepts and putting together the mantle and crust dynamic in the south Atlantic region. The plume migration of tectonic plates over fixed mantle plumes such as the Hawaiian-Emperor Chain needs to be discussed in the South Atlantic where direction and speed of plate motion changes and some ridges can tell this history (Vitória-Trindade Ridge, Pernambuco and Bahia seamounts, for example). The understanding of the dynamic of oceanic lithosphere and mantle is critical for the comprehension of the solid earth cycles, mantle convection and plate motion. This section will present and study models and hypotheses using the different geological and geophysical support to evaluate proposed models on genesis and evolution of intraplate volcanism related or not to mantle plumes.
Conveners: Peter Hackspacher, Anderson Costa
https://goldschmidt.info/2020/program/programViewThemes#session_471_4640
Session 05b: Submarine volcanic, magmatic, and hydrothermal processes
Keynote speaker: Isobel Yeo (NOC)
Roughly 80% of the active volcanism on Earth occurs within the oceans, with a wide range of activity style and potential hazards, and offering insights into the deep biosphere and the formation of economically important ore deposits. There is an ever-increasing wealth of diverse datasets about submarine volcanoes, including detailed bathymetry and seismic profiles of submarine structures; samples of eruption deposits and hydrothermal fluids by dredging, ROV and scientific ocean drilling surveys; and real-time monitoring of volcanic activity by remote sensing or seafloor observatories. This session focuses on volcanic, magmatic, and hydrothermal processes at submarine volcanoes in different tectonic settings: mid-ocean ridges, arcs, back-arcs, hot spots, and other intraplate settings, and from deep to shallow to partially submerged. We welcome abstracts focused on any aspect of submarine volcanism, including (but not limited to): variations in magma composition and eruption style, eruption processes, magma-water interactions, volcanic hazards, heat flux, hydrothermal mineralization, and how these processes vary across different tectonic settings and water depths. We also encourage abstracts outlining new approaches, emerging technologies, and recent discoveries in these environments. We hope this will spark discussion within the oral and poster sessions pertaining to the importance of seafloor exploration, utilizing existing datasets to their fullest potential, future studies, science communication, and public outreach.
Conveners: Iona McIntosh and Melissa Anderson
https://goldschmidt.info/2020/program/programViewThemes#session_471_4640
Session 08m: Ore deposits formed at or near the seafloor: A perspective from ancient and modern examples
Keynote speaker: Mark Hannington (University of Ottawa)
We are convening this session in honor of Steve Scott who was a pioneer in modern seafloor mineral deposit research and the applications to ancient ore deposits. Several valuable commodities are concentrated at or near the seafloor with different deposits forming and being preserved under different seawater redox conditions. These deposits contain several different commodities, including Cu-Pb-Zn deposits from VMS or SEDEX style deposits, Mn-Co-rich nodules, and REE-enriched phosphate deposits, but all depend in some way upon the local conditions of the ocean from which they form. Due to the ability to obtain detailed data from several aspects of the locations where these deposits are forming, much information can be gained about ancient deposits from understanding analogs forming on the seafloor today. Similarly, because ancient deposits that are being mined allow for easier collection of a wide range of samples in three dimensions, a robust understanding of modern deposits can be garnered by looking at ancient analogs. To that end, in this session, we aim to attract abstracts from researchers investigating strong metal enrichments forming at or near the seafloor in both modern and ancient environments. We hope this will spark discussion within the oral and poster sessions pertaining to techniques used in each of these fields and how modern/ancient investigations complement one another.
Conveners: Dan Gregory and Melissa Anderson
https://goldschmidt.info/2020/program/programViewThemes#session_474_4286
Session 08q: Processes of Hydrothermal Ore Formation for Base, Precious and Critical Metals
Keynote: Robert Linnen (University of Western Ontario)
The metallic mineral resources of our planet are mainly the products of hydrothermal processes. Although global metal production is dominated by base and precious metals, the supply-demand gap is greatest for the “critical” metals, because of their application in a variety of very new technologies, many of which are designed to address the most pressing societal issue of our time, global warming. Consequently, there is an especially urgent need to understand the processes by which “critical” metals are concentrated to exploitable levels in the Earth’ crust and, in turn, to develop reliable genetic models to guide their exploration. Even for the base and precious metals, however, there is considerable need to improve our models for their deposit genesis. This session aims to advance understanding of the processes controlling the transport and deposition of metals in hydrothermal systems. In particular, it aims to highlight 1) the role of nanoparticles (colloids) and organic species in metal transport and deposition in ancient and modern hydrothermal systems, and 2) the behaviour of critical metals in hydrothermal systems. Topics that will be addressed include: 1) Hydrothermal experiments and modelling of metal speciation, solubility and water/rock interaction; 2) Studies of ore fluid chemistry and the genesis of hydrothermal ore deposits; 3) Traditional and non-traditional analytical approaches to characterising spatial and temporal metallic mineral distributions; 4) Extraction and recovery of critical metals from hydrothermal ores and metal criticality assessment.
Conveners: Weihua Liu, Anthony Williams-Jones, Lingli Zhou, Sören Henning
https://goldschmidt.info/2020/program/programViewThemes#session_474_4602
Session 14e: Hydrothermal systems: Fluid chemistry, material fluxes, and biogeochemical processes
Hydrothermal systems, ranging from terrestrial hot springs to deep-ocean hydrothermal vents, profoundly influence the chemistry, biology, and oxidation state of Earth’s lithosphere-hydrosphere-atmosphere systems, generate important mineral resources, and host unique biological ecosystems. These processes have been at work throughout Earth’s history, and may function in habitable worlds beyond, now or in the past. Complex arrays of chemical, physical, and biological processes ultimately generate diversity in fluid compositions and hence the delivery of elements and dissolved gases to the receiving systems. The study of hydrothermal processes generally requires interdisciplinary efforts that integrate studies of modern measurements, extrapolations of the geologic record, laboratory experiments, and numerical models. In this session, we intend to host a forum for presenting and integrating these efforts in order to focus the community’s attention on answering key questions regarding magmatic and tectonic controls on submarine hydrothermal fluid chemistry, elemental fluxes from hydrothermal systems, the accumulation of metal-rich deposits on the seafloor, and the biologic habitability of such systems. In particular, we invite contributions focusing on the interpretation of measurements of modern hydrothermal systems; studies of recovered oceanic drill core, obducted oceanic lithosphere, or proxy records in ancient rocks; experimental exploration of hydrothermal (bio)geochemical interactions; and integrative numerical models that expand the spatiotemporal scales of these field and experimental observations. Specific focuses could include the interplay between magmatic and tectonic controls and the temperature and pressure conditions of hydrothermal reactions; the role of alteration processes in the geologic cycle of C, Fe, P, and other important elements; transport and degradation of sedimentary organic matter; the accumulation of metal-rich deposits on the seafloor; the contribution of submarine hydrothermal systems to seawater geochemistry through Earth history; interactions among organic molecules, minerals/metals, and microorganisms in hydrothermal environments; and the steps of biomolecular synthesis and accumulation and ability of hydrothermal systems to originate and/or support life on Earth and other planets. Experimental, computational, and field studies as well as analytical techniques used in uncovering hydrothermal fluid chemistry and identifying fluid compounds are all welcome.
Conveners: Benjamin Tutolo, Drew Syverson, Ziming Yang, Kirtland Robinson, Tobias Björn Weisenberger, Andri Stefansson
https://goldschmidt.info/2020/program/programViewThemes#session_480_4651
