Kum, B.-C.; Shin, D.-H.; Lee, J.H.; Moh, T.J.; Jang, S.; Lee, S.Y., and Cho, J.H., 2018. Monitoring Applications for Multifunctional Unmanned Surface Vehicles in Marine Coastal Environments. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1381–1385. Coconut Creek (Florida), ISSN 0749-0208. This work investigates the application of unmanned surface vehicles (USVs) for the management of coastal environment. USVs are an important and highly accessible tool for operating in shallow and nearshore waters. Sea trials are used to test the maneuverability and bathymetric survey capabilities of USVs. The results show that USVs have the potential to be an integrative platform for surveying shallow water zones (rivers, estuaries, and coasts), which can be enhanced by installing various transducers and sensor modules. The advances in sensing technologies and micro...

Sediment cores (A10 and I06) were analyzed using a high-resolution X-ray fluorescence (XRF) core scanner to understand changes in paleo-sedimentary environments of the study area. Age dating reflects environmental changes from interglacial marine isotope stage 3 (MIS 3) through the last glacial maximum (LGM; MIS 2) to the Holocene. Three layers were identified in the seismic profiles as follows: unit 1 (thickness = ca. 5 m) in a homogeneous sedimentary phase; unit 2 formed by erosion; unit 3, which is parallel and continuous. XRF elemental proxy data indicate anomalous distributions of Ca/Fe, Ca/K, and Fe/Ti caused by organic substances that appear at several depths in the A10 core. Results show that the seafloor was exposed to air during the LGM. The I06 core shows characteristic anomalies at depths of 0.8, 1.5, and 2.5 m, which were caused by sediments supplied from surrounding rivers.

A detailed analysis of high-resolution (3.5 kHz) chirp seismic profiles acquired in the Gunsan Basin of the central Yellow Sea revealed that hydrocarbon gases are actively seeping via the formation of many plumes. The uppermost sedimentary layer was acoustically confirmed to be fully or partially charged with gases. Somewhat favored by the low-tide period, episodic gas seepage is mainly associated with the underlying fault systems of Cretaceous-Cenozoic sedimentary strata in the southwestern part of the basin. Catastrophic gas expulsion seems to have formed a crater at the sidewall of a sedimentary ridge and two diapirs. Here, methane is poorly concentrated but rich in the heavy carbon isotope (δ¹³C, −52.6‰ to −44.7‰ The Vienna Peedee Belemnite [VPDB]), indicating that methane formed mainly through biodegradation of heavy oils at depth remains in the shallow sediments following its expulsion. Episodic rapid upward advection of porewater is also manifest by unmixed heavy methane trapped in the upper part of the primary biogenic methane (δ¹³C, about −90‰ VPDB)-filled sediment core. These findings imply that the Gunsan Basin fulfills the requirements for possible generation and preservation of oil and gas, like the petroliferous basins of eastern China and the Yellow Sea.