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High resolution multi-channel seismic reflection data (~1000 km) and multibeam echosounder bathymetry from the southeastern Korean continental shelf of the East Sea (Japan Sea) reveal numerous shallow gas indicators and seepage-related features, such as bright spots, enhanced reflections, seismic chimneys, acoustic blanking, pockmarks, and bathymetric mounds. Bright spots, indicating gas-charged layers, appear as local negative-polarity reflection anomalies (up to 5 km wide) and occur at various stratigraphic levels within a subsurface depth of ~320 m. Bright spots covering an area of ~60 km2 are clustered at the tip of NE-SW–trending reverse faults in the northeastern and southeastern part of the investigated region, suggesting gas entrapment. Enhanced reflections (ca. 20-km-long) are developed along erosional unconformities and tilted sedimentary layers below them. This suggests that unconformities formed during sea-level low stands in the study area are potential reservoirs and may have acted as potential conduits for lateral migration of gas-rich fluids due to their permeable nature. Some enhanced reflections are formed along interfluves of channels where channel walls cut them, and thus they may potentially act as fluid reservoirs. Seismic chimneys, expressed as vertical disturbances in seismic data, are interpreted as the upward movement of fluids (i.e., either in liquid or gaseous form). Lack of faulting in some seismic chimneys suggests higher permeability in the sedimentary interval, which would allow the migration of deeper-sourced fluids. Pockmarks (up to 500 m in diameter) are typically associated with seismic chimneys in the sub-seabed, suggesting that they were formed by the explosive emission of gas or gas fluids. Some exhibit mound-like features near their crests that are interpreted as carbonate mounds. The locations of mounds above uplifted fault blocks in the central part suggest a structural control on the formation of these seabed features. • Abundant shallow gas indicators on the southeastern continental shelf of Korea. • Amplitude anomalies indicating shallow gas are bright spots and enhanced reflections. • Seismic chimneys, acoustic blanking, pockmarks, and carbonate mounds are common. • Shallow gas accumulates both in structural and stratigraphic traps. • We propose a 2D model of shallow gas distribution. [ABSTRACT FROM AUTHOR]

About 1000 km of high-resolution seismic reflection profiles were used to study the morphology, distribution, nature, and sequence stratigraphy of incised valleys and valley fills within the Quaternary (

• Direct, selective leaching of Li from industrial-grade LIBs powder for the first time. • Omission of pre-leach powder separation shortens the process and reduces cost. • The role and mechanism of anode carbon in promoting selectivity were revealed. • Excellent selectivity and high Li leaching efficiency (Li greater than 97%, others < 1%). • Post-leaching solution is alkaline, circumventing neutralization for subsequent work. Demand for lithium-ion batteries (LIBs) is projected to maintain unprecedented acceleration for decades, towards satisfying international climate and source objectives. LIB wastes pose a threat to the environment, but also may be considered a strategic, high-grade resource. Yet, recycling the black mass of waste LIBs, which contains plastic, C, Li, Fe, Ni, Co, Mn, Cu, and Al, is very complex. Herein, the direct selective leaching of Li from the industrial-grade black mass powder of waste LIBs is proposed for the first time. Results demonstrated that the leaching efficiency of Li is shown to exceed 97%, while other metals remain below 1%. The mechanism of selective leaching was also investigated in this study. Under the experimental conditions, Fe is not leached out and remains in the form of solid FePO 4. As for other impurity metal elements, they are removed from the solution due to the alkaline environment of the post-leaching solution and the adsorption effect of the anodic carbon. Furthermore, the alkaline post-leaching solution can avoid the neutralizing stage before the precipitation of lithium salts. This highly efficient and Li-selective leaching strategy offers a broadly applicable approach to reclaiming critical energy minerals from the black mass of wasted LIBs. [ABSTRACT FROM AUTHOR]