Paleomagnetic Data and the Accretion of the Guerrero Terrane, Southern Mexico Continental Margin

2013 ◽  
pp. 73-92 ◽  
Author(s):  
H. Böhnel ◽  
L. Alva-Valdivia ◽  
S. Gonzalez-Huesca ◽  
J. Urrutia-Fucugauchi ◽  
D. J. Moran-Zenteno ◽  
...  
Keyword(s):  
Continental Margin ◽  
Paleomagnetic Data ◽  
Southern Mexico ◽  
Guerrero Terrane

Aeromagnetic anomalies and paleomagnetism in Jalisco and Michoacan, southern Mexico continental margin

1991 ◽  
Vol 192 (1-2) ◽  
pp. 169-190 ◽  
Author(s):  
L.M. Alva-Valdivia ◽  
J. Urrutia-Fucugauchi ◽  
H. Böhnel ◽  
D.J. Morán-Zenteno
Keyword(s):  
Continental Margin ◽  
Southern Mexico ◽  
Aeromagnetic Anomalies

Morphotectonic zones along the coast of the Pacific continental margin, southern Mexico

Geomorphology ◽  
1999 ◽  
Vol 28 (3-4) ◽  
pp. 237-250 ◽  
Author(s):  
Marı́a-Teresa Ramı́rez-Herrera ◽  
Jaime Urrutia-Fucugauchi
Keyword(s):  
Continental Margin ◽  
Southern Mexico ◽  
The Pacific

Mélanges in southern Mexico: geochemistry and metamorphism of Las Ollas complex (Guerrero terrane)

2000 ◽  
Vol 37 (9) ◽  
pp. 1309-1320 ◽  
Author(s):  
Oscar Talavera Mendoza
Keyword(s):  
High Pressure ◽  
Low Temperature ◽  
Early Cretaceous ◽  
Mineral Chemistry ◽  
White Mica ◽  
Island Arc ◽  
Southern Mexico ◽  
Calcic Amphibole ◽  
Guerrero Terrane

Las Ollas complex (LOC) is a subduction complex spatially associated with the early Cretaceous Zihuatanejo-Huetamo subterrane (Guerrero terrane) in southern Mexico. LOC tectonic mélanges compose of a stack of east-dipping, west-vergent tectonic sheets containing blocks of metabasalt, metadolerite, metagabbro, ultramafics, volcaniclastics, quartz-rich sandstone, and chert enveloped in a highly sheared clastic or serpentinitic matrix. Most igneous and igneous-derived metamorphic blocks show geochemical and isotopic features typical of island-arc tholeiitic suites: (i) low TiO2 (0.13 to 0.91%) and Zr (5 to 57 ppm) contents; (ii) high (LFSE/HFSE)N ratios; low LaN/YbN (0.5 to 4) values; and, high εNd(T) (+7.9 to +8.0) ratios. Petrographical and mineral chemistry evidence indicates that blocks underwent early recrystallization under high pressure and low temperature (HP-LT), blueschist facies conditions during subduction. Typical assemblages include blue (sodic through calco-sodic to Na-rich calcic) amphibole + lawsonite ± tremolite ± Mg-chlorite ± white mica ± albite ± quartz. Phase relations and chlorite thermometry suggest temperatures of about 200°-330o C and pressures of 5-7 kbar. It is proposed that sedimentary blocks were generated by in situ remobilization and mixing, whereas igneous blocks most probably derived from the chemically and isotopically identical Zihuatanejo island-arc suite. Our data suggest that LOC represents part of a subduction complex formed by eastward-directed subduction related with the evolution of the early Cretaceous Zihuatanejo island arc.

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