Abstract In situ observations under typhoon conditions are sparse and limited. Distributed acoustic sensing (DAS) is an emerging technology that uses submarine optical-fiber (OF) cables to monitor the sea state. Here, we present DAS-based ocean current when a super passed overhead. The microseismic noise induced by surface gravity waves (OSGWs) during Typhoon Muifa (2022) observed in ~0.08–0.38 Hz frequency band, with high-frequency (>0.3 Hz) component being tidally modulated. OSGW...

Abstract Mesoscale eddies are ubiquitous in the global ocean and can be captured by marine multichannel seismic surveys. In this study, a short‐lived anticyclonic eddy is characterized along line STEEP11 acquired on 30 September 2008 northern Gulf of Alaska. Fine‐scale stratification with alternative strong striae weak layers regarded as typical structure study region. The center dips NW tilted axis 1.9 ± 0.2° from horizontal. Submesoscale structures including fronts filaments coexist around...

Abstract Recently the novel seismic oceanography method has been reported to be an effective way study energetic internal solitary waves (ISWs) in northern South China Sea. An optimized seismic‐oceanographic cruise was carried out observe such near‐surface ISWs on Dongsha Plateau July 2014. Several soliton trains rather than single solitons were captured using technique. After data processing, one prototypical rank‐ordered ISW packet northeast side of Island clearly identified for further...

Abstract Marine seismic reflection technique is used to observe the strong ocean dynamic process of nonlinear internal solitary waves (ISWs or solitons) in near‐surface water. Analysis ISWs problematical because their transient nature and limitations classical physical oceanography methods. This work explores a Markov Chain Monte Carlo (MCMC) approach recover temperature salinity ISW field using reflectivity data situ hydrographic data. The MCMC designed directly sample posterior probability...

Abstract The Mariana Ridge is one of the prominent mixing hotspots open ocean. high-resolution underway marine seismic reflection technique provides an improved understanding spatiotemporal continuous map ocean turbulent mixing. Using this novel technique, study quantifies diapycnal diffusivity subthermocline (300–1200-m depth) turbulence around Ridge. autotracked wave fields on images allow us to derive dissipation rate ε and K ρ based Batchelor model, which relates horizontal slope spectra...

Internal solitary waves (ISWs) in the NE South China Sea (SCS) are tidally generated at Luzon Strait. Their propagation, evolution, and dissipation processes involve numerous issues still poorly understood. Here, a novel method of seismic oceanography capable capturing oceanic finescale structures is used to study ISWs slope region SCS. Near-simultaneous observations two were acquired using satellite imaging, water column measurements. The vertical horizontal length scales observed around 50...

Abstract In this work, a secondary nonlinear internal wave (NIW) on the continental shelf of northern South China Sea is investigated using high‐resolution seismic imaging and joint inversion water structure properties combined with in situ hydrographic observations. It an extraordinary combination two mode‐2 NIWs one elevated NIW occurring within short distance 2 km. The most energetic part could be regarded as upper layer between 40 120 m depth. vertical particle velocity ∼41 cm/s may...

Abstract Recent works show that the seismic oceanography technique allows us to relate water column reflections oceanic finescale structures. In this study, structures of a surface anticyclonic eddy have been unveiled by reprocessing two transects acquired in northern Gulf Alaska using an 8 km hydrophone streamer and 6600 cu linear airgun array September 2008. The was typical bowl‐like structure with around 55 width 700 m depth. It has fringes base spiral arm at NE edge. situ sea temperature...

Many physical phenomena in the ocean involve interactions between water masses of different temperatures and salinities at boundaries. Of particular interest is characterisation finescale structure marginal interaction zones these boundaries, where either destroyed by mixing or formed stratification. Using high-resolution seismic reflection imaging, we present observations temporal changes leading edge an interface sub-thermocline layers Panama Basin. By studying time-lapse images a...

Ocean current measurements play a crucial role in aiding our understanding of ocean dynamics and circulation systems. Traditional methods, such as drifters buoys, are sparsely distributed limited effectiveness due to the nature marine environment high operating expenses. Distributed acoustic sensing (DAS) is an emerging technology using submarine optical-fiber (OF) cables dense seismo-acoustic arrays, offering new perspective for observations. Here, situ observations surface gravity waves...

Internal solitary waves (ISWs) are investigated offshore of Guangdong in the northern South China Sea (SCS) using high-frequency acoustic backscatter data 100 kHz acquired July 2020. Simultaneous XBT profiles and satellite images incorporated to understand their propagation, evolution, dissipation processes shallow water at depths less than 50 m. The column structures revealed by consistent with a small difference 3 A soliton train apparent vertical horizontal scales ∼7 m, respectively, is...

In this paper, a velocity model of the Southern Depression Tainan Basin is obtained along with its migrated image from an iterative pre-stack depth migration approach.The Cenozoic strata are uniformly layered velocities varying ~1.8 to ~3.6 km s -1 .However, general slightly lower in NW segment than SE.Both fractures and burial might be controls their seismic velocities.There unconformable contact between underlying Mesozoic abrupt jump ~3.2 ~4.3 .The recognized acoustically distinct...

Abstract. A legacy seismic transect acquired on 30 and 31 May 2009 in the southern South China Sea (SCS) was reprocessed to reveal thermohaline structure of water column. In study region, a mesoscale subsurface lens with extraordinary features detected at 113.5° E, 11.5° N. It is centred 450 m depth, occupies both intermediate from 250 600 m, has an intersection diameter around 60 km. The simulated results Hybrid Coordinate Ocean Model eddy-induced current running southwestward along deep...

Ocean submesoscale dynamics are thought to play a key role in both the climate system and ocean productivity, however, subsurface observations at these scales remain rare. Seismic oceanography, an established acoustic imaging method, provides unique tool for capturing oceanic structure throughout water column with spatial resolutions of tens meters. A drawback seismic method is that temperature salinity not measured directly, limiting quantitative interpretation imaged features. The Markov...

Abstract The deep ocean to the east and south of Taiwan Island‒including Okinawa Trough, Ryukyu Arc, Philippine Sea, Luzon Strait, northeast South China Sea‒is one most prominent mixing hotspots global ocean. high‐resolution seismic reflection technique can provide detailed views water's finestructure near‐transient turbulent therein. Using legacy data from two cruises, we present quantify within thermocline sub‐thermocline (100–1,000 m depths) offshore Taiwan. We derive dissipation rate ε...

The northern margin of the South China Sea (SCS) is often regarded as a magmapoor passive continental margin.Magmatic activities occurred after cessation seafloor spreading were founded mainly over Continent-Ocean Transition (COT) zone.Intrusive rocks are observed in Luzon-Ryukyu Transform Plate Boundary (LRTPB) dividing Southwest Taiwan Basin (SWTB) and Pearl River Mouth (PRMB) north COT their evolution mechanisms not very well-studied.Here, detailed structural geophysical features...

Abstract. Flow separation can occur when a stratified flow passes over an obstacle. Previous studies concerning are mostly observed in the shallow water regions, e.g., fjord, driven by tidal flows. In this study, novel view of separations intermediate Hengchun Ridge and Ryukyu Arc off Taiwan is firstly reported using seismic oceanography reprocessing data from two cruises 97306 EW9509 2001 1995, respectively. Both images show that masses separated internal interfaces detached sill crests....