Deep ventilation in the Okinawa Trough induced by Kerama Gap overflow

Herein, the temporal variability of the deep overflow through the Kerama Gap between the East China Sea and the Philippine Sea is investigated based on observational data combined with reanalysis data obtained during 2004–2011. The observations and model results show a strong bottom-intensified flow intruding into the deep Okinawa Trough. The observed deep overflow shows intraseasonal variations that are enhanced from August to November. The variability in the deep overflow via the Kerama Gap is well-correlated with the density changes near its sill depth in the Philippine Sea. Additionally, some portion of the dense water originates from a region east of Miyakojima, which can be related to the northeastward-flowing Ryukyu Current at intermediate depths. In contrast, three extreme deep overflow events indicate that the arriving mesoscale eddies propagated from the east resulted in an increase in the density near the Kerama Gap sill than that on the Okinawa Trough side. The density difference associated with the baroclinic pressure gradient across the Kerama Gap forced the deep overflow into the Okinawa Trough. The volume transport of the deep overflow computed by integrating the cross-sectional velocity and through hydraulic theory are 0.14 and 0.11 Sv (1 Sv = 106 m3/s), respectively.

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Characteristics of hydrocarbons in hydrothermal products of the Clam hydrothermal field from the Okinawa trough

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2021.112277 ◽

2021 ◽

Vol 167 ◽

pp. 112277

Author(s):

Xin Huang ◽

Chao Huang ◽

Yali Qi ◽

Xiaoyuan Wang ◽

Hansheng Cao

Keyword(s):

Okinawa Trough ◽

Hydrothermal Field ◽

The Okinawa Trough

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Element enrichment and U-series isotopic characteristics of the hydrothermal sulfides at Jade site in the Okinawa Trough

Science in China Series D Earth Sciences ◽

10.1007/s11430-009-0107-y ◽

2009 ◽

Vol 52 (7) ◽

pp. 913-924 ◽

Cited By ~ 8

Author(s):

ZhiGang Zeng ◽

ShaoXiong Yu ◽

XueBo Yin ◽

XiaoYuan Wang ◽

GuoLiang Zhang ◽

...

Keyword(s):

Okinawa Trough ◽

The Okinawa Trough ◽

Element Enrichment ◽

Hydrothermal Sulfides

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EXPRESS: A Piecewise Model for In Situ Raman Measurement of the Chlorinity of Deep-Sea High-Temperature Hydrothermal Fluids

Applied Spectroscopy ◽

10.1177/0003702821999114 ◽

2021 ◽

pp. 000370282199911

Author(s):

meng ge ◽

Lianfu Li ◽

Xin Zhang ◽

Zhendong Luan ◽

Zengfeng Du ◽

...

Keyword(s):

High Temperature ◽

Deep Sea ◽

Okinawa Trough ◽

Peak Position ◽

Hydrothermal Fluids ◽

Calibration Model ◽

The Okinawa Trough ◽

Temperature Ranges ◽

Piecewise Model ◽

C 50

The chlorinity of deep-sea hydrothermal fluids, representing one of the crucial deep-sea hydrothermal indicators, indicates the degree of deep phase separation of hydrothermal fluids and water/rock reactions. However, accurately measuring the chlorinity of high-temperature hydrothermal fluids is still a significant challenge. In this paper, a piecewise chlorinity model to measure the chlorinity of high-temperature hydrothermal fluids was developed based on the OH stretching band of water, exhibiting an accuracy of 96.20%. The peak position, peak area ratio and F value were selected to establish the chlorinity piecewise calibration model within the temperature ranges of 0-50Â°C, 50-200Â°C and 200-300Â°C. Compared with that of the chlorinity calibration model built based on a single parameter, the accuracy of this piecewise model increased by approximately 4.83-12.33%. This chlorinity calibration model was applied to determine the concentrations of Cl for high-temperature hydrothermal fluids in the Okinawa Trough hydrothermal field.

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