Mid-Norwegian Continental Margin Magmatism
- Proposal: #944-Full2, #944-Add2
- Scientific Prospectus
Reykjavik, Iceland to Kristiansand, Norway
the Mid-Norwegian margin
原因、気候への影響を理解しようとするJOIDES Resolution の航海です。
下記、英文全文：Mid-Norwegian Continental Margin Magmatism Expedition 396 is a scientific ocean drilling project that seeks to understand the nature, cause and climate implications of excess magmatism during the northeast Atlantic continental breakup. Competing geodynamic end-member hypotheses exist for the formation of this excess magmatism, but their relative importance remains unresolved: (1) elevated mantle potential temperatures associated with mantle plume processes, (2) enhanced material flux through the melt window during rifting caused by small-scale convection at the base of the lithosphere, and (3) mantle source heterogeneity that may contribute to anomalously high melt production during continental breakup. Voluminous magmatism also coincides with the global greenhouse climate in the early Paleogene and has been proposed as a driver of both short-term (Paleocene-Eocene Thermal Maximum) and long-term (early Eocene Climate Optimum) global warming. However, the timing of the magmatism is not sufficiently constrained. Improved constraints on melting conditions, timing of magmatism, magmatic fluxes in time and space, eruption environment, sedimentary proxy data, and relative timing of climate events are required to resolve these linked controversies. Expedition 396 is based on IODP Proposals 944-Full2 and 944-Add2 and will target volcanic and sedimentary sequences at nine primary sites along and across the mid-Norwegian margin.
This expedition will address five primary objectives: (1) determine the conditions of mantle melting; (2) determine spatial and temporal variations in along axis volcanic fluxes to test predictions made by fundamentally different geodynamic models for volcanic rifted margin formation including segmentation; (3) determine variations in the depositional environment (sub-aerial vs sub-marine) of inner and outer lava flows to test correlations between magma genesis and dynamic thermal support during late syn-rift, break-up, and early post-rift oceanic spreading; (4) assess the temporal evolution of the styles of volcanic and magmatic activity in relation to paleoclimate proxies to test the relationship between large-scale volcanism and climate change events; and (5) investigate the relative importance of environmental consequences of two key processes during the initial opening of the North Atlantic: direct volcanic degassing and explosive thermogenic gas release through hydrothermal vent complexes that expel fluids derived from contact metamorphism. The expedition will also address two important secondary objectives: (1) early Eocene hot-house and fresh water incursions into the Atlantic, and (2) carbon capture and storage in basalt provinces.
COVID-19 PROTOCOL: The JRSO has created a protocol to safely operate during the COVID-19 pandemic. If pandemic conditions have not improved by mid-2021, the expedition may need to sail with a reduced shipboard contingent. However, all participants will maintain their designation as science party members regardless of whether they sail or not, and will have equal access to all expedition data and core materials. The protocol is available here: http://iodp.tamu.edu/scienceops/JR_COVID-Mitigation-Protocols-2020-07-02.pdf.
WHO SHOULD APPLY: We encourage applications from all qualified scientists. The JOIDES Resolution Science Operator (JRSO) is committed to a policy of broad participation and inclusion, and to providing a safe, productive, and welcoming environment for all program participants. Opportunities exist for researchers (including graduate students) in most shipboard specialties, including but not limited to sedimentologists, volcanologists, petrologists, igneous geochemists, inorganic and organic geochemists, micropaleontologists, paleomagnetists, physical properties specialists, and borehole geophysicists. Good working knowledge of the English language is required.