Bulk compositional controls on the preservation of age domains within metamorphic monazite: A case study from quartzite and garnet–cordierite–gedrite gneiss of Thor-Odin dome, Monashee complex, Canadian Cordillera

2007 ◽  
Vol 240 (1-2) ◽  
pp. 85-102 ◽  
Author(s):  
Alana M. Hinchey ◽  
Sharon D. Carr ◽  
Nicole Rayner
Keyword(s):  
Canadian Cordillera ◽  
Monashee Complex

Northeastward extrusion and extensional exhumation of crystalline rocks of the Monashee complex, southeastern Canadian Cordillera

2000 ◽  
Vol 22 (5) ◽  
pp. 603-625 ◽  
Author(s):  
Dennis H. Johnston ◽  
Paul F. Williams ◽  
Richard L. Brown ◽  
James L. Crowley ◽  
Sharon D. Carr
Keyword(s):  
Crystalline Rocks ◽  
Canadian Cordillera ◽  
Monashee Complex

scholarly journals Assessing Inheritance of Zircon and Monazite in Granitic Rocks from the Monashee Complex, Canadian Cordillera

2008 ◽  
Vol 49 (11) ◽  
pp. 1915-1929 ◽  
Author(s):  
J. L. Crowley ◽  
R. L. Brown ◽  
F. Gervais ◽  
H. D. Gibson
Keyword(s):  
Granitic Rocks ◽  
Canadian Cordillera ◽  
Monashee Complex

U–Pb geochronologic constraints on the cover sequence of the Monashee complex, Canadian Cordillera: Paleoproterozoic deposition on basement

1997 ◽  
Vol 34 (7) ◽  
pp. 1008-1022 ◽  
Author(s):  
James L. Crowley
Keyword(s):  
Hanging Wall ◽  
Crystalline Basement ◽  
Detrital Zircons ◽  
Canadian Cordillera ◽  
Metasedimentary Rocks ◽  
Monashee Complex ◽  
Minimum Age ◽  
Age Constraints ◽  
Unconformable Contact ◽  
Different Parts

The cover sequence in the Monashee complex is a platformal metasedimentary succession that occupies a nearly unique position in the Canadian Cordillera due to its unconformable contact with exposed crystalline basement. Zircon U–Pb data and field observations show that the lower part of the sequence contains Paleoproterozoic rocks, the oldest known metasedimentary rocks in the Cordilleran miogeocline, and the upper part of the sequence is Mesoproterozoic or younger. Maximum age constraints on the lower part are provided by 1.99 Ga detrital zircons from the basal unit and a 1862 ± 1 Ma orthogneiss upon which it was presumably deposited. Minimum age constraints are provided by rocks that intruded into the lower part: 1852 ± 4 Ma pegmatite, 1762 ± 6 Ma leucogranite, and 724 ± 5 Ma syenitic gneiss. The upper part of the sequence must be considerably younger than the lower part because it contains a detrital zircon dated at ~1.21 Ga. Other detrital zircons, dated at Neoarchean (2.95–2.86 Ga) and Paleoproterozoic (1.85–1.81, 1.75 Ga), suggest a source in the western Canadian Shield. These ages constrain the thickness of Mesoproterozoic and Neoproterozoic metasedimentary rocks in the cover sequence to be < 2 km. Combining these ages with previously interpreted Paleozoic deposition ages for the middle and upper parts of the sequence constrains the thickness to be <0.2 km, considerably less than that of coeval rocks above the Monashee complex in the hanging wall of the Monashee décollement. Such a contrast suggests that deposition above and below the décollement occurred in different parts of the Cordilleran miogeocline.

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