First active hydrothermal vents on an ultraslow-spreading center: Southwest Indian Ridge

Abstract

First active hydrothermal vents on an ultraslow-spreading center: Southwest Email alerting services articles cite this article to receive free e-mail alerts when new www.gsapubs.org/cgi/alerts click Subscribe to subscribe to Geology www.gsapubs.org/subscriptions/ click Permission request to contact GSA http://www.geosociety.org/pubs/copyrt.htm#gsa click official positions of the Society. citizenship, gender, religion, or political viewpoint. Opinions presented in this publication do not reflect presentation of diverse opinions and positions by scientists worldwide, regardless of their race, includes a reference to the article's full citation. GSA provides this and other forums for the the abstracts only of their articles on their own or their organization's Web site providing the posting to further education and science. This file may not be posted to any Web site, but authors may post works and to make unlimited copies of items in GSA's journals for noncommercial use in classrooms requests to GSA, to use a single figure, a single table, and/or a brief paragraph of text in subsequent their employment. Individual scientists are hereby granted permission, without fees or further

230Th/238U dating of hydrothermal sulfides from Duanqiao hydrothermal field, Southwest Indian Ridge

“…Duanqiao hydrothermal field (50°28 0 E) was detected by deep-tow video imaging and measurements of weak Eh, pH, and H 2 S anomalies, and it is *200 m 9 125 m in extent, similar to the S zone at Dragon Flag hydrothermal field (Tao et al 2012) (Fig. 1b).…”

“…Hydrothermal activity in Dragon Flag Field is located next to the detachment fault termination. The detachment fault system provides a pathway for hydrothermal convection (Sauter et al 2009;Tao et al 2012;Zhao et al 2013). Such style of heat source can contribute to continuous hydrothermal activity for over 1000 years.…”

“…Duanqiao hydrothermal filed is located between the Indomed Fracture Zone (FZ) and Gallieni FZ at the central volcano at 50°28 0 E on the SWIR. It was first discovered by the R/V Dayangyihao cruise in 2008 (Tao et al 2012). Previous studies of Duanqiao hydorhermal field were mainly focused on geophysics and molecule biology.…”

Indian Ocean Hydrothermal Systems: Seafloor Hydrothermal Activities, Physical and Chemical Characteristics of Hydrothermal Fluids, and Vent-Associated Biological Communities

“…Very recently, a new hydrothermal vent site was discovered along the SWIR and was explored by a Chinese scientific team (Tao et al 2012). They found hydrothermal ventendemic fauna, including scaly-foot gastropods at the vent site.…”

“…A number of geological, geochemical, and biological studies have been conducted at MOR hydrothermal vent sites, providing important insight into the effect of MOR hydrothermal activity on ocean chemistry (e.g., Edmond et al 1979Edmond et al , 1982Von Damm et al 1985a, b;Palmer and Edmond 1989;Elderfield and Schultz 1996), the limit, origin, and early evolution of life (e.g., (Jannasch and Mottl 1985;Nealson et al 2005;Takai et al 2006;Takai 2011) as well as the diversity and connections among different biogeographical provinces of hydrothermal vent faunas (e.g., Van Dover et al 2002;Bachraty et al 2009;Vrijenhoek 2010). However, most of the hydrothermal vent sites discovered and investigated thus far are located in the Pacific and Atlantic Oceans (German and Von Damm 2004), whereas only a few hydrothermal fields have been identified in the Indian Ocean Hashimoto et al 2001;Van Dover et al 2001;Tao et al 2012;Nakamura et al 2012). Thus, the geological, geochemical, and biological features of the Indian Ocean hydrothermal system remain poorly understood, and it appears highly uncertain which features are common to global hydrothermal systems and which are unique to the Indian Ocean system.…”