Halocline eddies transport mass and energy across the Arctic Ocean. The understanding of these eddies is elementary because of the high resolution investigating lack. Seismic oceanography uses active source seismic waves (i.e., acoustic waves) to create high resolution images of the water column. It has been successfully used to image a variety of oceanic features, e.g., oceanic fronts, water mass boundaries, mesoscale eddies, internal solitary waves, and thermohaline staircases.

Here, we present high resolution water column images processed from multichannel seismic reflection data acquired during late summer 2011 on the Chukchi Borderlands in the western Arctic Ocean. Combined with coeval hydrographic measurements (e.g., current velocity, temperature, and sound velocity), we identified the mesoscale eddies and their related submesoscale processes in this region. The geometric parameters, distribution, and properties of these features were estimated. Coeval and historical hydrographic data were also used to interpret the unique reflection structures related to eddies through seismic forward modelling.

A total of 23 mesoscale eddies were detected, of which 19 are anticyclonic, and 4 are cyclonic. The lentoid and mounded structures on seismic images represent anticyclonic and cyclonic eddies, and they correspond to a pair of extremum regions with opposed flow directions on the perpendicular section component velocity profiles and a single extremum value region on the along section component velocity profiles. Distinctive reflection structures are observed around the eddy core (e.g., chaotic, imbricate, layered, and listric reflections), which could constrain stirring and mixing process of the eddies. These eddies are mainly distributed in areas where the topography changes drastically, e.g., in the vicinity of seamounts and on both sides of the Northwind ridge. The statistical results show a positive linear correlation between the eddy core depth and apparent thickness, which may account for ambient stratification changes. A warm-core anti-cyclonic eddy and two cold-core anti-cyclonic eddies are discovered among the eddies, whose core water may come from Chukchi Summer Water and Pacific Winter Water, respectively. The total volume transport of these eddies can reach 0.56 Sv.

Our work shows the great scientific values for joint measurements in seismic oceanography. Distinctive reflection structures observed around the eddy core may help us to study the submesoscale process at the eddy’s edges. These results are also useful for providing a nearly synoptic, detailed view of the variety eddies in the Chukchi Borderlands, the western Arctic Ocean.