ANDEAN REACTIVATION OF THE CRETACEOUS SALTA RIFT, NORTHWESTERN ARGENTINA

被引:146
作者
GRIER, ME [1 ]
SALFITY, JA [1 ]
ALLMENDINGER, RW [1 ]
机构
[1] UNIV NACL SALTA,FAC CIENCIAS NAT,RA-4400 SALTA,ARGENTINA
关键词
D O I
10.1016/0895-9811(91)90007-8
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
Throughout the Andes, foreland geometries are correlated with the orientation of the subducting Nazca Plate: fold-and-thrust belts with steep subduction and basement uplifts with flat. The geometries observed in the southern Cordillera Oriental and northern Sierras Pampeanas do not fit this pattern. Instead, inversion of the Cretaceous Salta Rift Basin and mechanical differences between rift and non-rift domains are proposed as the primary controls on both the timing of late Tertiary uplift and deformation, and foreland geometries. The influence of the rift basin is documented through field observations of structures and lithologies, kinematic analysis of minor fault data, and published data on local stratigraphy. The southern Cordillera Oriental developed within the southwestern subbasin of the Salta rift and is a basement-involved fold-and-thrust belt. The Sierras Pampeanas developed to the south of the rift and are basement uplifts. Dominant structures in both regions are N/S-trending reverse or thrust faults. They are cut by oblique strike-slip faults. Older deformation is Mio-Pliocene in age and is characterized by thrust kinematics with E-W to NW-SE shortening. Younger deformation is Plio-Quaternary in age and is characterized by strike-slip kinematics with NE-SW shortening, except along the boundary between the Cordillera Oriental and the Sierras Pampeanas where thrust kinematics with N-S shortening prevail. The similar kinematics but different geometries in the two provinces during Mio-Pliocene deformation and the anomalous thrust kinematics observed during Plio-Quaternary deformation suggest that the Salta rift is the main control on structural geometries. A rift inversion model is developed and applied to the southern Cordillera Oriental.
引用
收藏
页码:351 / 372
页数:22
相关论文
共 61 条
[1]  
Acenolaza, El Paleozoico inferior de Argentina según sus trazas fósiles, Ameghiana, 15, pp. 15-64, (1979)
[2]  
Allmendinger, Jordan, Palma, Ramos, Perfil estructural en la Puna Catamarqueña (25-17°S), Argentina, Actas, V Congreso Latinoamericano Geológico, Buenos Aires, 1, pp. 499-518, (1982)
[3]  
Allmendinger, Ramos, Jordan, Palma, Isacks, Paleogeography and Andean structural geometry, northwest Argentina, Tectonics, 2, pp. 1-16, (1983)
[4]  
Anderson, The Dynamics of Faulting and Dyke Formation with Applications to Britain, (1951)
[5]  
Bahlburg, Ordovician clastic and volcanic rocks in the northern Puna of Chile and Argentina: Evidence of back-arc basin development west of the Faja Eruptiva de la Puna Oriental, XXVIII Symposium, International Geologic Congress, Washington DC, 1, (1989)
[6]  
Barazangi, Isacks, Spatial distribution of earthquakes and subduction of the Nazca Plate beneath South America, Geology, 4, pp. 686-692, (1976)
[7]  
Bercowski, Colada basáltica en la Formación Yacoraite (Cretácico Superior), pozoCaimancito, Norte Argentina, Resúmenes, III Simposio, Proyecto 242, PICG-UNESCO, pp. 36-41, (1987)
[8]  
Bevis, Isacks, Hypocentral trend surface analysis: Probing the geometry of Benioff Zones, Journal of Geophysical Research, 89, pp. 6153-6170, (1984)
[9]  
Bianucci, Acevedo, Cerdan, Evolución tectosedimentaria del Grupo Salta en la subcuenca Lomas de Olmedo (Provincias de Salta y Formosa), Actas, VIII Congreso Geológico Argentino, San Luis, 3, pp. 159-172, (1981)
[10]  
Bianucci, Homovc, Tectogénesis de un sector de la cuenca del Subgrupo Pirgua, Noroeste Argentina, Actas, V Congreso Latinoamericano Geológico, Buenos Aires, 5, pp. 539-546, (1982)