Summary
Mud volcanoes (MVs) are expulsion features ubiquitously present in areas of tectonic convergence both on land and on the seafloor. Due to their km-deep feeding channels, MVs are highly episodic structures, acting as valves to dissipate excess pore pressure building up at depth. Eruptions are deemed crucial to understand the regional geology and fluid-sediment interactions. However, the main drivers behind these sporadic bursts in activity still remain fairly obscure. It is hypothesized that different events can trigger MVs eruptions (e.g. gas accumulation, diagenetic processes, pore pressure build up), therefore originating a plethora of different effects with corresponding ejecta, channelled through the main conduits. Of all the MVs triggers, earthquakes (EQs) are the only ones for which a direct cause-effect relationship has been already established. The Gulf of Cadiz (GoC) is arguably one of the best playgrounds for the study of MVs and paleoseismology, due to the presence of an accretionary wedge with active fluid and solid expulsion structures (>90 MVs, at least three major transform faults, several pockmarks fields) and because of the numerous large magnitude EQs happened in the past, which are well preserved in the sedimentological record. Recently, three major seagoing expeditions led by MARUM (University of Bremen) and the ICM-CSIC set out to investigate the episodicity and nature of mud volcanism in the GoC, as well as its relationship with the tectonic and seismic history of the region. This talk will explore the main results from the aforementioned expeditions, which contributed to shed new light on the fluid and solid cycles of the SW Iberian Margin with an unprecedented level of detail, highlighting how a plethora of different processes is, in fact, fuelled by and contributing to the GoC mud volcanism.
Brief biography
Since his PhD at MARUM (University of Bremen), Dr. Menapace has been investigating different world regions affected by mud volcanism (Eastern Mediterranean, Gulf of Cadiz, Kumano Basin-Japan), mainly focusing on topics such as the activity of submarine MVs (mud volcanos) and their relationship with seismicity, but also aiming to explain the broader link between MVs and the subduction zone fluid and solid cycles. After his PhD, Dr. Menapace further expanded his knowledge on mud volcanism thanks to a DFG-related project where he studied, as PI, timing and evolutionary dynamics of the Mariana Forearc MVs following his participation to IODP366. In October 2020, Dr. Menapace was chief scientist onboard RV Meteor (M167) to retrieve long-term monitoring devices left on the Atlantic seafloor during the M149, two years before. The data collected during these expeditions led to him to explore a new branch of marine science, i.e. turbidite paleoseismology, for which he was awarded a Marie Curie scholarship. Despite the early stage of his career, Dr. Menapace has participated to 10 expeditions at sea with 6 different RVs and has already been two-times chief scientist.