Determining timescales of natural carbonation of peridotite in the Samail Ophiolite, Sultanate of Oman
Mervine, Evelyn M.
MetadataShow full item record
LocationSultanate of Oman
Determining timescales of the formation and preservation of carbonate alteration products in mantle peridotite is important in order to better understand the role of this potentially important sink in the global carbon cycle and also to evaluate the feasibility of using artificially-enhanced, in situ formation of carbonates in peridotite to mitigate the buildup of anthropogenic CO2 emissions in the atmosphere. Timescales of natural carbonation of peridotite were investigated in the mantle layer of the Samail Ophiolite, Sultanate of Oman. Rates of ongoing, low-temperature CO2 uptake were estimated through 14C and 230Th dating of carbonate alteration products. Approximately 1-3 x 106 kg CO2/yr is sequestered in Ca-rich surface travertines and approximately 107 kg CO2/yr is sequestered in Mg-rich carbonate veins. Rates of CO2 removal were estimated through calculation of maximum erosion rates from cosmogenic 3He measurements in partiallyserpentinized peridotite bedrock associated with carbonate alteration products. Maximum erosion rates for serpentinized peridotite bedrock are ~5 to 180 m/Myr (average: ~40 m/Myr), which removes at most 105-106 kg CO2/yr through erosion of Mg-rich carbonate veins.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2012
Showing items related by title, author, creator and subject.
Lee, Kwok-Lin (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1997-01)This thesis investigates the petrology and geochemistry of an abyssal peridotite dredged from the Atlantis II Fracture Zone in the southwestern Indian Ocean Ridge. Texturally, this sample is a serpentinized peridotite ...
Trace element geochemistry of oceanic peridotites and silicate melt inclusions : implications for mantle melting and ocean ridge magmagenesis Johnson, Kevin T. M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1990-06-15)The mantle melting process is fundamental to basalt genesis and crustal accretion at mid-ocean ridges. It is believed that melts ascend more rapidly than the surrounding mantle, implying a process similar to fractional ...
Geochemical and fluid dynamic investigations into the nature of chemical heterogeneity in the Earth's mantle Hauri, Erik H. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1992-09)Variations in the abundances of elements and radiogenic isotopes in mantle derived peridotites and volcanic rocks are chemical integrals over time, space, and process, which ultimately contain information about the role ...