Document Type
Article
Publication Date
3-20-2016
Keywords
Hydrothermal alteration, Hydrothermal mineralization
Abstract
Kick’em Jenny is a frequently erupting, shallow submarine volcano located 7.5 km off the northern coast of Grenada in the Lesser Antilles subduction zone. Focused and diffuse hydrothermal venting is taking place mainly within a small (~70 3 110 m) depression within the 300 m diameter crater of the volcano at depths of about 265 m. Much of the crater is blanketed with a layer of fine-grained tephra that has undergone hydrothermal alteration. Clear fluids and gas are being discharged near the center of the depression from mound-like vents at a maximum temperature of 180ᵒC. The gas consists of 93–96% CO2 with trace amounts of methane and hydrogen. Gas flux measurements of individual bubble streams range from 10 to 100 kg of CO2 per day. Diffuse venting with temperatures 5–35ᵒC above ambient occurs throughout the depression and over large areas of the main crater. These zones are colonized by reddish-yellow bacteria with the production of Fe-oxyhydroxides as surface coatings, fragile spires up to several meters in height, and elongated mounds up to tens of centimeters thick. A high-resolution photomosaic of the inner crater depression shows fluid flow patterns descending the sides of the depression toward the crater floor. We suggest that the negatively buoyant fluid flow is the result of phase separation of hydrothermal fluids at Kick’em Jenny generating a dense saline component that does not rise despite its elevated temperature.
Publication Title
Geochemistry, Geophysics, Geosystems
Volume
17
First Page
1000
Last Page
1019
Required Publisher's Statement
AGU Publications
DOI: 10.1002/2015GC006060
Link to publisher version: http://onlinelibrary.wiley.com/doi/10.1002/2015GC006060/full
Recommended Citation
Carey, Steven; Olsen, Rene; Bell, Katherine L. C.; Ballard, Robert; Dondin, Frederic; Roman, Chris; Smart, Clara; Lilley, Marvin; Lupton, John; Seibel, Brad; Cornell, Winton; and Moyer, Craig L., "Hydrothermal venting and mineralization in the crater of Kick’em Jenny submarine volcano, Grenada (Lesser Antilles)" (2016). Biology Faculty and Staff Publications. 51.
https://cedar.wwu.edu/biology_facpubs/51
Subjects - Topical (LCSH)
Submarine volcanoes--Antilles, Lesser; Island arcs--Antilles, Lesser; Hydrothermal vents--Antilles, Lesser; Biomineralization
Geographic Coverage
Antilles, Lesser
Genre/Form
articles
Type
Text
Language
English
Format
application/pdf
Comments
AGU allows final articles to be placed in an institutional repository 6 months after publication.