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Post-Laramide and Pre-Basin and Range Tectonophysics 471 (2009) 136–152 Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto Post-Laramide and pre-Basin and Range deformation and implications for Paleogene (55–25 Ma) volcanism in central Mexico: A geological basis for a volcano-tectonic stress model Margarito Tristán-González a,b,1, Gerardo J. Aguirre-Díaz b,⁎, Guillermo Labarthe-Hernández a, José Ramón Torres-Hernández a, Hervé Bellon c a Instituto de Geología/DES Ingeniería, Universidad Autónoma de San Luis Potosí, Av. Dr. Manuel Nava 5, Zona Universitaria, 78240, San Luis Potosí, Mexico b Centro de Geociencias, Universidad Nacional Autónoma de México, Campus UNAM-Juriquilla, Querétaro, Querétaro, 76230, Mexico c UMR 6538, Domaines Océaniques, IUEM, Université de Bretagne Occidentale, 6, Av. Le Gorgeu, C.S. 93837, F-29238 Brest Cedex 3, France article info abstract Article history: At central-eastern Mexico, in the Mesa Central province, there are several ranges that were formed after the Received 3 May 2008 K/T Laramide compression but before the Basin and Range peak extensional episodes at middle–late Accepted 23 December 2008 Oligocene. Two important volcano-tectonic events happened during this time interval, 1) uplift of crustal Available online 13 January 2009 blocks exhuming the Triassic–Jurassic metamorphic sequence and formation of basins that were filled with red beds and volcanic sequences, and 2) normal faulting and tilting to the NE of these blocks and Keywords: fanglomerate filling of graben and half-graben structures. The first event, from late Paleocene to early Eocene, Volcano-tectonics – Paleocene–Oligocene was related to NNE and NNW oriented dextral strike-slip faults. These faults were combined with NW SE en Basin and Range extension echelon faulting in these blocks through which plutonism and volcanism occurred. The second event lasted Sierra Madre Occidental volcanism from early Oligocene to early Miocene and coincided with Basin and Range extension. Intense volcanic Mexico activity occurred synchronously with the newly-formed or reactivated old fault systems, producing thick sequences of silicic pyroclastic rocks and large domes. Volcano-tectonic peaks occurred in three main episodes during the middle–late Oligocene in this part of Mexico, at about 32–30 Ma, 30–28 Ma, and 26– 25 Ma. The objectives of this work is to summarize the volcano-tectonic events that occurred after the end of the Laramide orogeny and before the peak episodes of Basin and Range faulting and Sierra Madre Occidental Oligocene volcanism, and to discuss the influence of these events on the following Oligocene–Miocene volcano-tectonic peak episodes that formed the voluminous silicic volcanism in the Mesa Central, and hence, in the Sierra Madre Occidental. A model based upon geological observations summarizes the volcanic- tectonic evolution of this part of Mexico from the late Paleocene to the Early Miocene. © 2009 Elsevier B.V. All rights reserved. 1. Introduction McDowell, 1991; Ferarri et al., 2005). According to Aguirre-Díaz and Labarthe-Hernández (2003) these two geologic provinces overlap in An elevated plateau in central Mexico, with an average elevation of space and time throughout their extent across Mexico, including Mesa about 2000 m above sea level (Fig. 1), includes some of the best Central. The eastern border of Mesa Central is marked by the Sierra mapped Tertiary volcanic areas of Mexico. It is known as Mesa Central, Madre Oriental folded belt (Fig. 2), which is composed of Mesozoic which is described as part of the southern Basin and Range marine sediments deformed during the Laramide orogeny at late extensional province (Henry and Aranda-Gómez, 1992; Stewart, Cretaceous–early Paleocene (De Cserna, 1956; Tardy et al., 1975; 1998; Nieto-Samaniego et al., 1999; Aranda-Gómez et al., 2000; Padilla, 1985; Chávez-Cabello et al., 2004 –Fig. 2). Other ranges, fault- Nieto-Samaniego et al., 2005) and the Sierra Madre Occidental bounded and with Triassic metamorphosed basement cores, can be volcanic province (McDowell and Clabaugh, 1979; Aguirre-Díaz and observed near this eastern margin and towards the interior of the Mesa Central (Fig. 2). These ranges have been interpreted also as caused by the Laramide orogeny (Martínez-Pérez, 1972; Aguillón- Robles- Tristán-González, 1981; Labarthe-Hernández et al., 1982a,b; ⁎ Corresponding author. Gallo-Padilla et al., 1993; Gómez-Luna et al., 1998), but our data E-mail addresses: [email protected] (M. Tristán-González), [email protected] (G.J. Aguirre-Díaz). presented here indicates that they were apparently formed after 1 Tel.: +52 444 8171039. Laramide orogeny. 0040-1951/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.tecto.2008.12.021 M. Tristán-González et al. / Tectonophysics 471 (2009) 136–152 137 Fig. 1. Index map of the Sierra Madre Occidental and Mesa Central provinces indicating the location of the study area. Most of the studies in this area have focused either on the Laramide observations, which can be used as a case study to test experimental or compression-related structures and Mesozoic stratigraphy or on the mathematical volcano-tectonic stress models of continental crust that Basin and Range extension-related structures and Oligocene Sierra was first submitted to an intense compressive stress regime (Laramide Madre Occidental volcanism. In contrast, little is known on the fault- orogeny), then to a crustal relaxation and trans-tension stress period, bounded structures with Triassic and Jurassic cores mentioned above and finally to an intense extensional regime (Basin and Range ex- because the available works have been published in local internal tension); all of these occurring at the final stages of a long-lasting geological reports (e.g., Labarthe-Hernández et al., 1982a,b, 1995; continental-margin subduction regime (Aguirre-Díaz and McDowell, Tristán-González and Torres-Hernández, 1992; Tristán-González et al., 1991). Similar situations have been reported in other places and dif- 1995). From these reports, it can be inferred that important volcano- ferent geologic times with the result of an intense period of rhyolitic– tectonic events occurred between the late Paleocene and the late andesitic volcanism in the form of domes and/or stratovolcanoes and Oligocene that developed these fault-bounded ranges and some fault- ignimbrites; for instance, at the Catalan Pyrenees, where Permian– bounded basins as well, synchronously with plutonism and volcanism. Carboniferous ignimbrites are apparently related to calderas influ- The main purpose of this study is to summarize the volcano- enced by the strike-slip tectonics (Martí, 1991), or at the Taupo tectonic events that occurred between the end of the Laramide Volcanic Zone, where silicic caldera volcanism and andesitic strato- orogeny and the initiation of Basin and Range faulting and Sierra volcanoes can be associated with rift-extension and trans-tension Madre Occidental Oligocene volcanism. We discuss the influence of respectively (Spinks et al., 2004). Using the particular case of the Sierra these events on the following Oligocene–Miocene volcano-tectonic Madre Occidental, Aguirre-Díaz et al. (2007, 2008) have coined the peak episodes that formed the voluminous silicic volcanism in the term of graben calderas for these types of volcano-tectonic caldera Mesa Central, and hence, in the Sierra Madre Occidental. In order to structures. achieve these goals, the stratigraphy, geochronology and structure of three representative areas of the Mesa Central are briefly described, 1) 2. Tectonic framework La Ballena-Peñón Blanco range, 2) Las Minas range and 3), Ahualulco basin (Fig. 2). The first and second cases represent fault-bounded The northern, northeastern and eastern limits of the Mesa Central ranges with Triassic and Lower Cretaceous basement cores, respec- are formed by the ranges of the Sierra Madre Oriental folded belt tively, and the third one, a listric-fault basin that initiated as a pull- (Fig. 3). Several studies have been undertaken in this belt to apart basin filled with a volcano-clastic sequence. understand the tectonic shortening at this area during the Upper This work provides a volcano-tectonic evolution model of a large Cretaceous–Early Tertiary, and in particular, on the portion where the area in central Mexico (Figs. 1, 2), based upon rigorous geological belt makes a turn to the west at the Monterrey salient or “Curvatura de 138 M. Tristán-González et al. / Tectonophysics 471 (2009) 136–152 Fig. 2. Digital elevation model showing the main tectonic structures in the eastern and southeastern part of Mesa Central. 1—Sierra de Catorce, 2—Sierra de Coronado, 3—Sierra de Charcas, 4—Sierra Santa Catarina, 5—Sierra de Guanamé, 6—Sierra Las Minas, 7—Sierra La Ballena-Peñón Blanco, 8—Sierra de Zacatecas; A—Ahualulco Basin, B—Coronado Basin; C— Matehuala-El Huizache Basin; D—Villa de Arista Basin; E—Peotillos Basin; F—Aguascalientes Graben; G—Villa de Reyes Graben; SLPVF—San Luis Potosí Volcanic Field; MC—Monterrey Curvature. Monterrey” (Fig. 3, De Cserna, 1956; Tardy et al., 1975; Padilla, 1985; southward from the Monterrey salient and forms the eastern limit of Chávez-Cabello et al., 2004). This deformation is characterized by the Mesa Central. From this eastern boundary and towards the inner folding and thrusting of the upper crust with an ENE transport parts of the Mesa Central the folded belt changes to fault-bounded direction, as well as by transcurrent faulting associated
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