hydrothermal vents presentation
TRANSCRIPT
Alterations of Earth’s crust and seawater caused by hydrothermal vent activity of black smokers at mid-ocean ridges
Lizzy PennockMARE 461December 1st, 2014
Mid-Ocean Ridge• Formation• Divergence of plates• Heat source• Permeable crust
• Hydrothermal circulation of seawater• Transformation into ‘vent water’
Black Smoker Overview• Hydrothermal vent• 300-400°C• Rich in metals• Create chimneys and massive plumes
Chimney
Purpose
• Explore process of hydrothermal circulation at black smokers
• Chemical changes of seawater and crust
The Recharge Zone
• Water enters crust• Oxidation • At the end of this
phase:• Slightly acidic• Anoxic• Alkali metals• Mg depleted
The Reaction Zone
• Maximum depth • Hottest
• Sulfur leaching• Heavy metals• Final alterations
The Upflow Zone
• Buoyant water• Reactions unknown• Alteration pipe• Mixing
Seawater vs. Vent water
Crust Alterations
Green bars: min. estimates of element fluxes Purple bars: max. estimates
Conclusion
• Chemical alterations• Three phases• Vent water
Questions?
Picture Credit• http://www.whoi.edu/page.do?
pid=10095&tid=3622&cid=2401• http://
jjustinianomarinescience.weebly.com/introduction-to-mid-ocean-ridges.html• http
://www2.newton.k12.ma.us/~brendan_healy/S0998A270.7/Chapter%201%20Sec%201.4.pdf • http://oceanexplorer.noaa.gov/explorations/07fire/logs/
july31/media/brothers_blacksmoker.html • http://www.visions05.washington.edu/science/
investigations/smoker_dev.html