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We investigated the microscopic mineral characteristics of modern eolian dust particulates and the trace-element compositions of the siliciclastic fractions of these samples, collected from the Philippine Sea in 2014 and 2015, and conducted an air mass backwards trajectory analysis of dust particulates in the spring and winter of 2015, to better constrain the provenances and transport dynamics of dust delivered to this region. The microscopic minerals show obvious signatures of dust deposition and physical abrasion, indicating long-distance wind transport from the Asian deserts. The trace-element compositions (Zr–Th–Sc) display a binary mixture of eolian materials derived from the eastern Asian deserts and the central Asian deserts, which is similar to the result of the Sr–Nd isotopic compositions of modern sediment trap sediments collected on the Benham Rise in 2015. We demonstrate that modern dust sediments in the Philippine Sea primarily originate from the Ordos Desert (generally > 80%), while the contributions of the Taklimakan Desert and the Badain Jaran Desert are small. Eolian dust particulates raised from source regions are predominantly transported to the Philippine Sea by the East Asian winter monsoon, but not by the westerlies. In addition, our results indicate that increased precipitation in the source regions can result in relatively low dust fluxes in the Philippine Sea, and there is a period of 6–7 days for eolian dust originating from source areas to be delivered to the Philippine Sea. [ABSTRACT FROM AUTHOR]

The Sr and Nd isotopic compositions of siliciclastic sediments and the Nd isotopic compositions of planktonic foraminifera are investigated in sediment trap samples collected in 2015 at water depths of 500 and 2,800 m to (1) track the seasonal changes in the sources and transport patterns of siliciclastic sediments to Benham Rise, (2) constrain the Nd isotopic compositions of the planktonic foraminifera throughout the water column, and (3) assess the influences of lithogenic inputs on the Nd isotopic compositions of the water masses. We demonstrate that volcanic matter and eolian dust are derived primarily from Luzon Island and the Ordos Desert, respectively. In addition, we show that reduced precipitation over Luzon Island and the weakened East Asian winter monsoon intensity result in mass fluxes from Luzon Island and the eastern Asian deserts to the sea, respectively, that are weaker in the winter than in the spring. Furthermore, the εNd values of the foraminifera collected at a water depth of 500 m change slightly in 2015, suggesting negligible impacts of lithogenic Nd inputs characterized by significant seasonal flux variations. In contrast, the εNd values of the planktonic foraminifera collected at a water depth of 2,800 m are systematically more radiogenic and appear to display seasonal variability. Such results suggest the rapid modification of εNd values during the settling of planktonic foraminifera by the precipitation of Mn coatings derived from water masses at deposition depths, with greater contributions of colder water masses originating from the volcanic Luzon Island margin during the winter. Plain Language Summary: Based on the first report of Sr‐Nd isotopic compositions of siliciclastic sediments and Nd isotopic compositions of planktonic foraminifera in sediment trap samples collected from the western Philippine Sea in 2015 at water depths of 500 and 2,800 m together with the relevant current information, we try to recover the potential linkages between the East Asian winter monsoon strength, the East Asian summer monsoon (precipitation) intensity, and the siliciclastic sediment source‐to‐sink processes as well as the influences of lithogenic inputs on the Nd isotopic compositions of the water masses at the northern margin of the western Pacific Warm Pool in different seasons of 2015. On the one hand, we quantitatively estimate the eolian dust sources to the study area. On the other hand, we find the rapid changes in planktonic foraminiferal εNd values during settling in the western Philippine Sea. Such results are critical for effectively interpreting the siliciclastic sediment source‐to‐sink processes and marine circulation as well as the behind controlling mechanisms at low latitudes during the geological past. Key Points: The eolian dust sources to the western Philippine Sea are determined and quantifiedThe impacts of the East Asian monsoon on the siliciclastic fluxes to the Benham Rise are characterizedRapid changes in planktonic foraminiferal εNd values occur during settling in the ocean [ABSTRACT FROM AUTHOR]

Abstract: C37 unsaturated alkenones were analyzed on a core retrieved from the middle Okinawa Trough. The calculated U37 K′ displays a trend generally parallel with those of the oxygen isotopic compositions of two planktonic foraminiferal species, Neogloboquadrina dutertrei and Globigerinoides sacculifer, suggesting that in this region, SST has varied in phase with global ice volume change since the last glacial–interglacial cycle. The U37 K′-derived SST ranged from ca. 24.0 to 27.5 °C, with the highest value 27.5 °C occurring in marine isotope stage 5 and the lowest ∼24.0 °C in marine isotope stage 2. This trend is consistent with the continental records from the East Asian monsoon domain and the marine records from the Equatorial Pacific. The deglacial increase of the U37 K′-derived SST is ∼2.4 °C from the Last Glacial Maximum to the Holocene. [Copyright &y& Elsevier]