The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners.
As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
i
Oxygen and hydrogen isotopic evidence that Kamaʻehuakanaloa (Lōʻihi) Seamount hydrothermal systems are recharged by deep Pacific seawater
-
2023
-
-
Source: Deep Sea Research Part I: Oceanographic Research Papers, 197, 104049
[PDF-2.44 MB]
Details:
-
Journal Title:Deep Sea Research Part I: Oceanographic Research Papers
-
Personal Author:
-
NOAA Program & Office:
-
Description:We observed negative and positive δ18O and δ2H deviations from fluids collected at Kamaʻehuakanaloa (previously known as Lōʻihi) seamount relative to Pacific seawater from the same depth. Hydrothermal vents on the crater floor of Pele's Pit at Kamaʻehuakanaloa, at a depth of 1320 m, had δ18O and δ2H values as low as −0.19‰ and −0.3‰, respectively. Seawater collected within the caldera, within a zone 45 m above the crater floor, had δ18O and δ2H values as high as 1.15‰ and 6.5‰, respectively. In comparison, Pacific seawater at 1200 m and 1400 m at nearby station ALOHA exhibit intermediate δ18O and δ2H values of 0.2‰ and 0.34‰. The high δ18O and δ2H values observed in the caldera water-column may be explained by isotopic modification processes, including water-rock reactions. However, we did not observe a vent source with similar isotopic composition; this suggests that substantial hydrothermal flow is entering the caldera through unidentified sources, potentially individually small but collectively important. Further, the low δ18O and δ2H values of the crater floor vents cannot be readily explained by isotopic modification processes alone. We conclude the crater floor vents predominantly reflect the isotopic composition of the Pacific seawater entrained into the hydrothermal system. Our observations suggest recharging seawater is entrained from below >4500 m, in the zone of Pacific Bottom Water. These findings illustrate the heterogeneity of hydrothermal transport processes at a volcanic seamount and how seamount hydrothermal convection can provide a mechanism that may contribute to vertical ocean mixing by transporting deep bottom waters to intermediate ocean depths.
-
Source:Deep Sea Research Part I: Oceanographic Research Papers, 197, 104049
-
DOI:
-
ISSN:0967-0637
-
Format:
-
Publisher:
-
Document Type:
-
Funding:
-
License:
-
Rights Information:CC BY-NC-ND
-
Compliance:Library
-
Main Document Checksum:
-
Download URL:
-
File Type:
