The structure and formation of hydrothermal vent complexes in the Møre Basin: A proposal for scientific drilling testing the link between magmatism and global warming
Abstract
Magmatic sill intrusions in sedimentary basin cause heating and devolatilization of the host rock. The associated pressure build-up in the metamorphic aureoles may become sufficiently large to form pipe-like fluid flow features. These are called hydrothermal vent complexes and connect the aureoles with the paleosurface. It has been suggested that the volume of greenhouse gases released from the aureoles around voluminous sill complexes emplaced during formation of Large Igneous Provinces (LIPs) is sufficiently large to trigger global warming, e.g. the emplacement of North Atlantic Igneous Province (NAIP) sill complexes in the mid-Norwegian Vøring and Møre basins may have triggered the Paleocene-Eocene Thermal Maximum (PETM) about 55.8 million years ago. Extensive new 3D seismic reflection data covering the Modgunn Arch area in the northern Møre Basin have recently been acquired. Interpretation of the Top Paleocene horizon in this cube shows that more than ten hydrothermal vent complexes are buried by less than a few hundred meters of post-breakup sediments. These vent complexes have eye- and crater-like upper parts and chimney-like lower parts that are characterized by disrupted seismic reflections. At their base the disrupted chimneys terminate at high-amplitude reflections interpreted as sill intrusions. The structure of these hydrothermal vent complexes resemble the seismic structure of modern vent complexes such as the LUSI and Porong features in Java, Indonesia, suggesting a common origin. We have proposed to sample the internal structure of the ancient hydrothermal vent complexes in the northern Møre Basin by scientific drilling. The main objective of this drilling proposal is to determine the proposed link between the hydrothermal venting and the PETM. This area is particularly well suited for shallow scientific drilling as the upper part of the vent complexes are reachable by the IODP vessel JOIDES Resolution's drill string.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMOS41B1664P
- Keywords:
-
- 0448 Geomicrobiology;
- BIOGEOSCIENCES;
- 1620 Climate dynamics;
- GLOBAL CHANGE;
- 3004 Gas and hydrate systems;
- MARINE GEOLOGY AND GEOPHYSICS;
- 4219 Continental shelf and slope processes;
- OCEANOGRAPHY: GENERAL