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Multiple seas in East Asia have played distinct roles during the Quaternary climatic cycles, which have repeatedly isolated and reconnected temperate forest species, while it remains unclear whether their roles differ. In this study, we used Smilax sieboldii, a widely distributed species along the eastern coast of East Asia, to simultaneously evaluate the roles of multiple seas, including the East China Sea, the Yellow‐Bohai Sea, the Korea‐Tsushima Strait, and the Taiwan Strait, as geographic barriers and dispersal corridors during historical sea‐level fluctuations. We employed Bayesian clustering analysis and demographic simulations to elucidate the genetic structure and evolutionary history. The effects of spatial or environmental differences on population structure were examined through isolation by distance (IBD) and isolation by environment (IBE) tests. Further, genetic differentiation and gene flow were used as indicators to assess the roles of different seas as barriers or corridors. A pronounced phylogeographic structure was observed in S. sieboldii, with populations divided into three distinct gene pools separated by the East China Sea and the Korea‐Tsushima Strait, accompanied by significant genetic admixture at the lineage boundaries. The lineage divergence occurred during the early Quaternary, while secondary contact began in the most recent interglacial period. During population differentiation, the East China Sea and the Korea‐Tsushima Strait acted as effective geographic barriers, whereas the Taiwan Strait and the Yellow‐Bohai Sea functioned more as dispersal corridors and facilitated greater gene flow. Meanwhile, IBD rather than IBE explained the population structure of S. sieboldii. To conclude, the phylogeographic patterns of S. sieboldii resulted from population isolation and admixture due to sea‐level fluctuations since the Pleistocene, and the spatial scale of a sea largely determined its ecological role among the multi‐sea systems. These findings improved our understanding of how paleoclimate changes and geological transformations have shaped the speciation and diversification of temperate forest species in East Asia. This study revealed how regional seascapes differentially drove genetic divergence in a deciduous climbing plant, Smilax sieboldii. Results support that both the Korea‐Tsushima Strait and the East China Sea acted as significant geographic barriers to historical gene flow in contrast to both the Yellow‐Bohai Sea and Taiwan Strait.

The Upper Eocene–Oligocene sequence exposed northwest Birket Qarun; Fayum district covers two rock units, Qasr El-Sagha (Temple and Dir Abu Lifa members) and Gebel Qatrani formations were re-evaluated by sequence stratigraphy. Six depositional sequences were recognized based on facies geometry, and sedimentological aspects. The first sequence (Temple Member) was accumulated under marginal intertidal flat environment indicating highstand deposits. The second (the lower Dir Abu Lifa Member) displays a regressive sedimentary facies starting with progradational delta front environment reflecting lowstand deposits followed upward by a lagoonal environment indicating transgressive/highstand deposits. The third (the top of the Dir Abu Lifa Member) was accumulated under a low sinuosity stream reflecting lowstand deposits. The fourth which constitutes the topmost of Dir Abu Lifa Member initiating near-shore shallow marine points to transgressive sediments, followed upward by fluvial sediments reflecting highstand deposits. The fifth (the Lower of Gebel Qatrani Formation) accumulated as point-bar deposits demonstrating lowstand deposits. The last occupies the main of Gebel Qatrani Formation initiates with restricted riverine marking lowstand deposits, followed upward by several fining upward cycles that were accumulated in fluvial and flood plain conditions with evidence of tidal influence on sedimentation near its top denoting transgressive deposits. Several minor transgressive episodes accompanied by tidal influence on sedimentation are noticed near the top, which may reflect gradual subsidence of the Oligocene alluvial plain. The area is subjected to relative sea-level changes that show a similarity with the global sea level. The base-level fluctuations are mainly controlled by the regional tectonic setting.

The coastal sediments are sensitive carriers that reveal climate change, sea-level fluctuations, and monsoon evolution. A large number of sedimentary sequences developed along the coast of the Shandong Peninsula in the Last Glacial Period. Previous studies mainly focused on material sources and climate characteristics, but seldom mention the ten-thousand-year timescale monsoon evolution and its relationship with sea level fluctuations. The Liukuang section (LKS) is adjacent to the North Yellow Sea, which is mainly composed of alternations of dune sand and paleosol of the Last Glacial. Based on the chronological framework constructed by AMS 14C and optically stimulated luminescence (OSL) dating, we measured grain size, geochemistry, and heavy minerals to reconstruct the evolution of the East Asian winter monsoon (EAWM) and climatic fluctuations during the Last Glacial Period. The variations of the climate proxy indicators show that the degree of dry-cold climate and EAWM strength are indicated by different sedimentary facies in dune sand > sandy paleosol > lacustrine > silty paleosol. On a ten-thousand-year timescale, we detected episodes of EAWM strengthened in the LKS4 (78.9–59.5 ka), LKS3b (50.5–39.6 ka) and LKS2 (29.7–13.1 ka), which correspond to Marine Isotope stage (MIS) MIS4, MIS3b and MIS2, respectively, and EAWM weakened in the LKS3c (59.5–50.5 ka) and LKS3a (39.6–29.7 ka), which correspond to MIS3c and MIS3a, respectively. These climatic events were essentially synchronous with climate changes recorded in the geological carriers such as the cave stalagmites of southern China, loess from the Chinese Loess Plateau (CLP), and sea-level fluctuations in the Yellow-Bohai Sea. It is believed that the external driving factor is from the changes of solar radiation, and the internal factor is mainly from the combined effect of monsoon changes and sea-level fluctuations.

This study examines the relative sea-level changes during the Upper Holocene period along the south coastline of Cyprus through the investigation of beachrock formations and their impact on archaeological sites. Beachrock, as a natural indicator of past relative sea levels, provides valuable insights into the dynamic interplay between sea-level fluctuations and human settlements. The research integrates field observations, mineralogical and geochemical analysis, geochronological studies, and archaeological data to reconstruct past sea-level variations and their implications for coastal archaeological sites. The results reveal significant fluctuations in relative sea levels during the Upper Holocene, influencing the development and occupation of coastal archaeological sites. By elucidating the complex relationship between sea-level changes and human activity, this study contributes to our understanding of past coastal environments and their socio-cultural dynamics. Moreover, it underscores the importance of considering geological factors in archaeological interpretations and coastal management strategies in the face of contemporary sea-level rise.

Aim: The respective contribution of vicariance and/or dispersal events to the evolution of clades dwelling in the archipelagic parts of the Oriental and Australian regions remains equivocal. Using a complete, species-level phylogeny of Polyura butterflies that are widespread in the oriental Palaeotropics, we aim to test predictions related to vicariance driven by past abiotic factors in the Indo-Australian archipelago (IAA) (Miocene tectonics and Pleistocene climatic shifts) versus repeated trans-archipelagic dispersal events. Location: The Oriental and Australian regions with a focus on the IAA. Methods: Bayesian species tree phylogenetic analyses were conducted using a matrix comprising two mitochondrial and two nuclear gene fragments. Bayesian relaxed clocks were used to produce a chronogram, which was used in ancestral area estimations to infer the spatio-temporal evolution of the genus at different geographical scales. Diversification dynamics were investigated using the package TreePar in R. Results: Polyura originated during the mid-Miocene (c. 13 million years ago).Ancestral area estimations inferred an origin in Indomalaya. Wallacea was colonized out-of-Indomalaya in the P. pyrrhus group, while the P. athamas and P.eudamippus groups diversified in Indomalaya and the east Palaearctic. We inferred three long-distance dispersal (LDD) events. The first one implies outof-Sunda colonization of the Solomon Islands, which have three extant, endemic species. The second implies a colonization of Vanuatu out-of-Sunda that later served as a stepping stone for the colonization of other Pacific islands (Fiji and New Caledonia). A third permitted the reverse colonization of Wallacea from the Pacific islands. These LDD events were supported by our diversification analyses that suggested no diversification rate shift throughout the evolution of the genus. Main conclusions: Our results suggest unusual colonization routes with Pacific islands as a hub for late Miocene reverse colonizations back into the centre of the Indo-Australian archipelago.

Sediment components and their fluxes of Cores MD12-3428（water depth： 903 m）, MD12-3433（water depth： 2125 m）,and MD12-3434（water depth： 2995 m）, obtained along a transect on the continental slope of the northern South China Sea, have been conducted to reveal the spatiotemporal variations and the controlling factors of the sediment components and of their fluxes.Results show that deep-sea sediments in the northern South China Sea are composed mainly of terrigenous（59–89%） and carbonate（6–38%） particles, with minor components of opal（1.6–9.4%） and organic matter（0.7–1.9%）. Fluxes of terrigenous and carbonate particles reach up to 2.4–21.8 and 0.4–6.5 g cm^–2 kyr^–1, respectively, values that are one to two orders of magnitude higher than the fluxes of opal and organic matter. Temporal variations of the percentages and fluxes of deep-sea sediment components have displayed clear glacial-interglacial cyclicity since the last glaciation. Terrigenous, opal, and organic matter percentages and their fluxes increas clearly during marine isotope stage 2, while carbonate percentages and fluxes show an opposite variation pattern or are characterized by an unremarkable increase. This implies that deep-sea carbonate in the South China Sea is affected by the dilution of terrigenous inputs during the sea-level lowstand. With increasing water depth along the transect, the terrigenous percentage increases but with largely decreased fluxes. Both the percentage and flux of carbonate decrease, while the percentages and fluxes of opal and organic matter display much more complicated variational features. The spatiotemporal variations of deep-sea sediment components and of their fluxes since the last glaciation in the northern South China Sea are strongly controlled by sea-level fluctuations. Simultaneously, terrigenous supply associated with monsoonal rainfall, marine primary productivity,and the dilution effect between terrigenous and biogenic particles, also play interconnected roles in the sediment accumulation processes.

The North Yellow Sea, located at the intersection of the Eurasian continent and North Pacific Ocean at mid-latitudes, is a sensitive area subjected to the joint actions of the ocean, land, and monsoons. On its southern shore, loess and paleosol sedimentary sequences were widely developed during the last interglacial period, which is of great significance for revealing patterns of climate change and dynamic conditions. In this paper, we focus on the Zhifu section (ZFS) on Zhifu Island within the Shandong Province of China. The optically stimulated luminescence (OSL) dating method was used to construct our chronological framework. Grain size and its endmember (EM) components were then analyzed; EM1 is a clay component EM, which represents a weak dynamic environment and strong weathering pedogenesis, while EM2 and EM3 are silt and very fine sand component EMs, respectively, representing a strong dynamic environment and weak weathering pedogenesis. Maximum EM1, mean grain size, clay content, and pH values occur in the paleosol layers (ZF4, ZF6, and ZF8), with minimum values in the loess layers (ZF5 and ZF7); EM3 values show the opposite pattern. This indicates that the ZF4, ZF6, and ZF8 layers represent warm and humid environments with abundant precipitation, where the East Asian summer monsoon (EASM) was enhanced, corresponding to Marine Isotope Stages (MIS) 5a, 5c, and 5e. In contrast, ZF5 and ZF7 represent sub-warm and humid environments with less precipitation, where the EASM was weakened, corresponding to MIS 5b and 5d. Among these stages, MIS5e is the warmest and wettest. These climatic events reveal the pattern of climate fluctuation over a ten-thousand-year timescale; they are synchronous with climate changes recorded in other geological repositories, such as cave stalagmites in southern China and sea-level fluctuations in the Yellow-Bohai Sea, which result from changes in global solar radiation.

Casares-Salazar, R. and Mariño-Tapia, I., 2016. Influence of the remote forcing and local winds on the barotropic hydrodynamics of an elongated coastal lagoon. The main objective of this study is to investigate the effects of local winds and sea-level variations at tidal and subtidal frequencies on the water levels, depth-averaged velocities, and volume fluxes of an elongated and shallow coastal lagoon using field measurements and a barotropic two-dimensional numerical model. Tides are mainly diurnal and attenuate ~85% from the mouth to the lagoon head, indicating a barotropic propagation dominated by friction. On the other hand, the low-frequency water-level fluctuations propagate with little attenuation (~17%), dominating the water-level variability at the lagoon head. It is considered important to elucidate whether this low-frequency variability is related to local winds or to remote effects. Modeling results show that local winds can increase water levels up to ~1.9 cm in the lagoon head (5% of tide level), whereas remote sea-level variability accounts for up to ~26.6 cm (320% of astronomical tidal level), clearly dominating lagoon water levels. On the other hand, diurnal sea breezes play a minor role in water levels inside the lagoon and do not reinforce diurnal tides in order to generate an important set-up. The cumulative water volume is highly correlated with sea level and shows that low-frequency sea-level fluctuations are especially efficient at accumulating or exporting water from the lagoon during periods of ascending or descending sea level, respectively. This implies that water exchange between the lagoon and the coastal ocean is dominated not only by diurnal tides but also by the low-frequency sea-level fluctuations of astronomical and meteorological origin (i.e. wind forcing through Ekman transport). El principal objetivo de este estudio es investigar los efectos de los vientos locales y las variaciones del nivel del mar en las frecuencias mareales y submareales de los niveles de agua, velocidades promediadas en la profundidad e intercambios de agua con el mar en una laguna costera alargada y somera, con base en mediciones de campo y un modelo numérico barotrópico en 2D. Las mareas son principalmente diurnas y se atenúan ~85% desde la boca hasta la cabeza de la laguna indicando una propagación barotrópica dominada por fricción. Por otro lado, las fluctuaciones de baja frecuencia en los niveles de agua se propagan con poca atenuación (~17%) dominando la variabilidad del nivel del agua en la cabeza. Es importante elucidar si esta variabilidad de baja frecuencia está relacionada con los vientos locales o se debe a los efectos remotos. Los resultados de modelación muestran que los vientos locales pueden incrementar los niveles de agua hasta ~1.9 cm en la cabeza de la laguna (5% sobre el nivel de marea), mientras que la contribución de la fluctuación de baja frecuencia fue de hasta ~26.6 cm (320% sobre las mareas astronómicas), controlando los niveles de agua dentro de la laguna a frecuencias submareales. Por otro lado, las brisas marinas de frecuencia diurna juegan un rol menor en los niveles de agua dentro de la laguna y no refuerzan a las mareas diurnas para causar un incremento importante del nivel del agua. Los volúmenes acumulados a través de secciones transversales están altamente correlacionados con el nivel del mar y muestran que las fluctuaciones de baja frecuencia del nivel del mar son especialmente eficientes para acumular o exportar agua de la laguna durante períodos de ascenso y descenso de esta variable, respectivamente. Esto implica que los intercambios de agua entre la laguna y el océano costero están dominados no solo por las mareas diurnas sino principalmente por las fluctuaciones de baja frecuencia del nivel del mar, cuyos orígenes son astronómicos y meteorológicos (i.e. forzamiento del viento a través del transporte de Ekman).

The features of the formation of the relief of the Solovetskiy Islands at different stages of development under the influence of natural and anthropogenic factors are considered. In the pre-Quaternary, denudative plains were dominant here. In the late Pleistocene, glacial and glaciolacustrine plains were formed. In the Holocene, glacial plains were preserved almost unaltered in the center of the islands. In the edge zones of the islands, where the glacial relief was subjected to intense wave action, stepped abrasion-accumulation-type plains were developed. These are made of a series of marine terraces that formed as a result of glacioisostatic uplifts and eustatic sea level fluctuations. To clarify the factors that determine the different prominence and elevation of marine terraces in the different parts of the archipelago is one of the main problems in the study of the island relief.

Small stress changes such as those from sea level fluctuations can be large enough to trigger earthquakes. If small and large earthquakes initiate similarly, high‐resolution catalogs with low detection thresholds are best suited to illuminate such processes. Below the Sea of Marmara section of the North Anatolian Fault, a segment of ≈$\\approx $ 150 km is late in its seismic cycle. We generated high‐resolution seismicity catalogs for a hydrothermal region in the eastern Sea of Marmara employing AI‐based and template matching techniques to investigate the link between sea level fluctuations and seismicity over 6 months. All high resolution catalogs show that local seismicity rates are larger during time periods shortly after local minima of sea level, when it is already rising. Local strainmeters indicate that seismicity is promoted when the ratio of differential to areal strain is the largest. The strain changes from sea level variations, on the order of 30–300 nstrain, are sufficient to promote seismicity. Plain Language Summary Quasi‐periodic phenomena are a natural probe to test how the Earth's responses to a certain stress perturbation. High‐resolution catalogs with low detection thresholds may provide a new opportunity to look for this type of earthquake triggering. A segment of 150 km below the Sea of Marmara section of the North Anatolian Fault is late in its seismic cycle. Here, we generated high‐resolution seismicity catalogs for 6 months covering a hydrothermal region south of Istanbul in the eastern Sea of Marmara including seismicity up to MW 4.5. For first time in this region, we document a strong effect of the Sea of Marmara water level changes on the local seismicity. Both high‐resolution catalogs show that local seismicity rates are significantly larger during time periods shortly after local minima on sea level, when the sea level is rising. The available local instrumentation provided an estimate of the strain changes that were sufficient to promote seismicity. If such small stress perturbations from sea level changes are enough to trigger seismicity, it may suggest that the region is very close to failure. Key Points We generated enhanced seismicity catalogs to investigate the potential link between sea level change and seismicity in a hydrothermal region Higher seismicity rates from the entire and declustered catalogs are observed during time periods when sea level is rising Strain estimates from local strainmeters show that seismicity was promoted during reduced normal and enhanced shear strain conditions