TY - JOUR
T1 - Sm-Nd and Zircon U-Pb ages from garnet-bearing ecologites, NE Oman : constraints on High-P metamorphism
AU - Gray, D.R.
AU - Hand, M.
AU - Mawby, J.
AU - Armstrong, R.A.
AU - Miller, John
AU - Gregory, R.T.
PY - 2004
Y1 - 2004
N2 - Poly-deformed and poly-metamorphosed glaucophane-eclogite mega-boudins beneath the Samail Ophiolite, Oman record an early subduction-related high-P metamorphism as well as subsequent overprinting deformation and metamorphism related to exhumation. Previously published Rb/Sr ages of 78 Ma and 40Ar/39Ar ages of 82–79 Ma record the major NE-directed shearing event that partially exhumed the eclogites to a shallower crustal level. New Sm/Nd garnet–garnet leachate–whole rock isochron data from garnet-bearing eclogite assemblages in the As Sifah subwindow in NE Oman are 110±9 Ma (DG02-87D); 5-point isochron) and 109±13 Ma (DG02-86E; 3-point isochron). On the basis of microfabric and field structural relationships these ages are interpreted to reflect the timing of prograde, peak high-P metamorphism in the rocks structurally beneath the Samail Ophiolite. This metamorphism clearly predates the age of formation of the obducted Samail oceanic lithosphere (97–94 Ma) as well as the subsequent obduction onto the margin (80–70 Ma). A U–Pb SHRIMP zircon age from small (
AB - Poly-deformed and poly-metamorphosed glaucophane-eclogite mega-boudins beneath the Samail Ophiolite, Oman record an early subduction-related high-P metamorphism as well as subsequent overprinting deformation and metamorphism related to exhumation. Previously published Rb/Sr ages of 78 Ma and 40Ar/39Ar ages of 82–79 Ma record the major NE-directed shearing event that partially exhumed the eclogites to a shallower crustal level. New Sm/Nd garnet–garnet leachate–whole rock isochron data from garnet-bearing eclogite assemblages in the As Sifah subwindow in NE Oman are 110±9 Ma (DG02-87D); 5-point isochron) and 109±13 Ma (DG02-86E; 3-point isochron). On the basis of microfabric and field structural relationships these ages are interpreted to reflect the timing of prograde, peak high-P metamorphism in the rocks structurally beneath the Samail Ophiolite. This metamorphism clearly predates the age of formation of the obducted Samail oceanic lithosphere (97–94 Ma) as well as the subsequent obduction onto the margin (80–70 Ma). A U–Pb SHRIMP zircon age from small (
U2 - 10.1016/j.epsl.2004.03.016
DO - 10.1016/j.epsl.2004.03.016
M3 - Article
SN - 0012-821X
VL - 222
SP - 407
EP - 422
JO - Earth & Planetary Science Letters
JF - Earth & Planetary Science Letters
IS - 2
ER -