Journal
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
Volume 490, Issue -, Pages 227-239Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.palaeo.2017.11.002
Keywords
Sediment provenance; Climate change; Northern Okinawa Trough; East China Sea; Elements geochemistry; Clay minerals
Funding
- National Natural Science Foundation of China [41622603, 41576034, U1606401]
- National Program on Global Change and Air-Sea Interaction [GASI-GEOGE-03]
- Innovation Project [2016ASKJ13]
- Aoshan Talents program of Qingdao National Laboratory for Marine Science and Technology [2017ASTCP-ES01]
- CAS Interdisciplinary Innovation Team
Ask authors/readers for more resources
High resolution multi-proxy records, including geochemical and grain-size data from detrital sediments of IODP Site U1429 in the northern Okinawa Trough, provide reliable evidence for constraining sediment source and transport processes. They also allow silicate weathering and erosion controlled by sea-level change and East Asian summer monsoon evolution since 34 ka to be reconstructed. Provenance proxies indicated that sediments in the northern Okinawa Trough were mainly supplied by the Yellow River middle reach at similar to 34-8 ka. The low sea level and proximity of paleo-Yellow River mouth to the northern Okinawa Trough were the causes of the dominant Yellow River input. After 8 ka, a retreated Yellow River mouth coupled with the blocking effect of the Kuroshio Current and its branches, together with strong East Asian summer monsoon precipitation resulted in relatively strong sediment input from Kyushu to the northern Okinawa Trough. Meanwhile, Yellow River upper reach supplied more sediments to the study site than that during the similar to 34-8 ka. On glacial-interglacial scale, silicate weathering proxies indicate that the core sediment was more weathered during the last glacial and deglacial than that in the modern Yellow River. We attribute this to the increased upper reach sediment input, which supplied more weak weathered sediment to the study site during the Holocene. Besides, composite effect of weathering during glacial and deglacial sediment production and additional weathering upon subaerial exposure of shelf deposits during low sea-level stage, as well as older weathered sediments reworking during sea level rise could also account for this weathering regime. On multi-Millennial scale, from similar to 34 to 18.5 ka, silicate weathering was mainly controlled by the East Asian summer monsoon, with a cooling and drying climate associated with weakened summer monsoon activity. This is consistent with the reduced alteration of sediments eroded from the Yellow River basin. From similar to 18.5 to 8 ka, strong reworking of older weathered sediments overwhelmed the East Asian summer monsoon in controlling silicate weathering, which induced a continuous increase in chemical alteration of the sediments during this period.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available