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Title: Data report: 87Sr/86Sr in pore fluids from IODP Expeditions 372 and 375, Hikurangi margin
We report on the Sr isotopic compositions of pore fluids recovered during International Ocean Discovery Program (IODP) Expeditions 372 and 375. Pore fluid samples were acidified and loaded directly onto columns containing EICHROM Sr spec resin, followed by analyses using a NU multicollector inductively coupled plasma–mass spectrometer (MC-ICP-MS). The strontium systematics in this margin point to a series of processes that include carbonate diagenesis, ash alteration, and diffusive exchange with the underlying oceanic crust. The role of ash alteration is evidenced at all drilled sites by a decrease in the 87Sr/86Sr ratio in the upper 130 m of the sediment column to values as low as 0.70846. In the calcareous early Paleocene to late Miocene sediment from Site U1520, the pore fluid strontium concentration shows a marked increase to 1280 µM at 647.3 meters below seafloor (mbsf), but the corresponding 87Sr/86Sr ratios do not show a significant change is this unit. In the early Late Cretaceous sediment at this site, there is an increase in dissolved strontium concentration with a corresponding decrease in 87Sr/86Sr ratios to 0.706312 at the bottom of the cored section.  more » « less
Award ID(s):
1326927
PAR ID:
10229044
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the International Ocean Discovery Program
Volume:
372B/375
ISSN:
2377-3189
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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