Submarine landslide triggered by volcanic eruption recorded by in situ hydrophone

Abstract

NW Rota-1 is a submarine volcano in the Mariana volcanic arc that is notable as the site where underwater explosive eruptions were fi rst witnessed in A.D. 2004. After years of continuous low-level eruptive activity, a major landslide occurred at NW Rota-1 in August 2009, triggered by an unusually large eruption that produced 10 times the acoustic energy of the background level of activity. An anomalous earthquake swarm preceded the eruption, suggesting that the sequence started with a magmatic intrusion and associated faulting beneath the volcano. We quantify the size and extent of the landslide using bathymetric resurveys and interpret the timing of events using data from an in situ hydrophone. This is the fi rst instrumental documentation of an earthquake-eruption-landslide sequence at a submarine volcano, and illustrates the close interaction between magmatic activity and mass wasting events in the growth of undersea arc volcanoes.

Eruptive modes and hiatus of volcanism at West Mata seamount, NE Lau basin: 1996-2012

“…Although this zone has a maximum depth change of only +17 m, it encompasses a well‐defined band with minimal variability within its boundary. As their names imply, we interpret these contiguous dual zones of negative (PV East landslide) and positive (PV East landslide deposit) depth change zones resulting from a submarine landslide similar to those documented at Monowai volcano [ Chadwick et al ., ; Wright et al ., ; Watts et al ., ] and at NW Rota‐1 submarine volcano [ Chadwick et al ., ]. Note that the volume of the PV East landslide (Table ) exceeds the PV East landslide deposit by a factor of ∼2.…”

“…Direct observations of active submarine volcanic activity have been made at just two sites, both within a magmatic arc/back‐arc setting. The eruption of NW Rota‐1, a seamount located in the southern Mariana arc, was discovered in 2003 [ Embley et al ., ] and was still active during the last in situ observations in 2010 [ Chadwick et al ., ]. The eruption of West Mata seamount, a submarine volcano located in the NE Lau basin (Figure ), was detected in 2008 with water column sensors [ Resing et al ., ].…”

Strain-level genomic variation in natural populations ofLebetimonasfrom an erupting deep-sea volcano

“…The seamount has been erupting ever since and between the 2009 and 2010 research expeditions, a landslide dramatically changed the topography of the seamount (Chadwick et al, 2012). Here, we use Lebetimonas as a model organism to examine the genomic diversity within one species of Epsilonproteobacteria from a single dynamic seamount, using low temperature diffuse vent fluids as a 'window' into the subseafloor habitat (Deming and Baross, 1993).…”

Contrasting styles of deep-marine pyroclastic eruptions revealed from Axial Seamount push core records

“…8A). Given arguments above for a primary pyroclastic origin (Resing et al, 2011;Deardorff et al, 2011;Chadwick et al, 2012a), we suggest that ballistic fallout and shortlived grain flows associated with small-volume eruption explosivity built steep pyroclastic aprons locally around vents that episodically failed forming large turbidity flows and LPT lithofacies (step 7 in Fig. 8A).…”