Uplift analysis on a pericratonic region: An example in the Sierras de Córdoba (29°–34°S), Argentina
Introduction
The Sierras de Córdoba, between 29° and 34°S (Fig. 1A–B), is an intraplate basement-involved thrust belt located in the easternmost part of the Sierras Pampeanas geological province of central Argentina (Caminos, 1972; Gordillo and Lencinas, 1979). This is part of the Central Andean broken foreland (cf. Jordan and Allmendinger, 1986) or pericratonic foreland (cf. Dávila et al., 2010), where Miocene to recent Andean tectonics has been modest to negligible. Nevertheless, its modern relief is near 3000 m, which is particularly remarkable considering the Sierras de Cordoba is located >800 km from the Perú-Chile trench (Fig. 1A). Foreland deformation and uplift in the Sierras de Córdoba have been associated with the slab flattening of the oceanic Nazca plate developed at these latitudes since the latest Miocene (Fig. 1A; Kay and Mpodozis, 2002; Ramos et al., 2002; Dávila and Lithgow-Bertelloni, 2015 and references therein), contemporaneously with retroarc volcanism in the region (“Pocho field”, Kay and Gordillo, 1994). But, even though this belt is one of the most referenced world examples for intraplate mountain building (DeCelles et al., 2014), its driving mechanisms and main controls on topography are poorly understood. In fact, there are still strong controversies and debate about the timing and magnitude of changes in Sierras de Córdoba topographic relief evolution. Some works suggest that topography has persisted through time since the Middle Jurassic to Paleogene, with relief controlled by weathering and/or pedimentation processes (Rabassa et al., 2010, and references therein). Others, in contrast, propose that modern relief is a product of a unique and significant phase of tectonic forcing during the Miocene to recent times (Jordan and Allmendinger, 1986; Kay and Gordillo, 1994; Ramos et al., 2002), overlapped by dynamic mantle processes forcing epeirogenic uplift (Dávila and Lithgow-Bertelloni, 2015). While the scarce and poorly constrained stratigraphic cross-cutting relationships (e.g., Casa Grande Fm., see Astini et al., 2014 and references therein) suggest basement thrusting and Andean uplift during the Neogene, low-temperature thermochronology (e.g., Löbens et al., 2011; Bense et al., 2013; Dávila and Carter, 2013; Richardson et al., 2013) and paleosurface analysis (Rabassa et al., 2010), in contrast, evidence pre-Andean activity, between Middle Jurassic and Paleogene (Fig. 1B).
Given that the landscape in a mountain system is the result of a complex interaction between surface processes (erosion and climate) and crustal processes (tectonics), DEM-based geomorphometry at drainage-basin scale (Snyder et al., 2000; Kirby and Whipple, 2001) might assist us in unraveling the main controls on the long- and short-term uplift history in the Sierras de Córdoba. Particularly, it will assist us in detecting the most recent uplift activity, from the beginning of Andean deformation to present, because rivers are very sensitive recorders of vertical motion over time scales of 102–106 yrs (e.g., Seeber and Gornitz, 1983; Merritts et al., 1994; Whipple and Tucker, 1999; Allen, 2008; Roberts and White, 2010). In this contribution, we analyze longitudinal stream profiles to determine uplift patterns (e.g., Kirby and Whipple, 2001, Kirby and Whipple, 2012; Wobus et al., 2006) in the Sierras de Córdoba. Our study will allow us to define semi-quantitatively areas affected by different uplift rates within hundreds to millions of years to understand the main controls on the landscape evolution. We compare our topographic analyses (elevation and local relief) and morphometric indexes (ksn and θ), calculated at the scale of individual drainage basins, with geological and mean annual precipitation data to address the controversies described above on the contribution of Andean uplift to the relief of Sierras de Córdoba. Our analysis will allow us not only to understand the along-strike variations and likely controls but also to design new strategies to study the uplift and landscape evolution of distal foreland elevations, where thermo- and geo-chronology is frequently poor or lacks resolution.
Section snippets
Geological and tectonic setting
The Sierras de Córdoba (located 63°30′–65°30′ W and 29°–34° S, Fig. 1B) is the most distal part of the Andean foreland, between the main Andean belts and the Chaco-Pampean Plain. This means that the Sierras de Córdoba can be considered as a large (~550 km, measured along strike) and isolated topographical anomaly. It has a regional base level near 300 m a.s.l. on both flanks and maximum elevations near 3000 m a.s.l. (the highest peak is the “Cerro Champaquí”, ca. 2884 m a.s.l.).
The Sierras de
Geomorphometric analysis
Topographic features in intraplate settings are the result of the interaction between sublithospheric, crustal and climatic processes (e.g., Ascione et al., 2008; Karlstrom et al., 2012). In this sense, as a first approach, the identification of topographic anomalies might be used as proxies to understand the influence of tectonic and erosional processes acting on the landscape. Given that fluvial networks react and leave markers during such processes, stream longitudinal profiles could later
General topographic characterization and local relief distribution
The Sierras de Córdoba shows a physiography with strong topographic variabilities along strike (N-S) for ~550 km (Fig. 3A). The present-day topography is defined by general asymmetric elevation profiles, with steep western slopes and gentle eastern slopes, bounded by elongated intermontane valleys (Carignano et al., 2014, and reference therein). However, some symmetric topographic profiles are associated with structural particularities (e.g., double-verging fault systems, Martino et al., 2014
Stream longitudinal profiles: equilibrium vs. transient landscape conditions
On the basis of the stream evolution of Gilbert (1877), under constant climate and uniform erosion, the mathematical approaches used in this study (Howard, 1994, Howard et al., 1994, see Section 3.2) allow predicting equilibrium conditions, when smooth and concave-up stream longitudinal profiles (graded profiles) develop. On the other hand, knickpoints separating different stream segments evidence transient profiles and disequilibrium conditions (Snyder et al., 2000; Wobus et al., 2006).
The
Conclusions
Our DEM-based geomorphometric analysis complemented with 242 stream longitudinal profiles throughout the Sierras de Córdoba (and their northward extension), based on a combined analysis of geological maps, geophysical and annual mean rainfall data, enabled us to evaluate the role of lithology, tectonics and climate within the most distal Andean foreland elevations. We found complex relationships among these controls along strike. Our study suggests that the Sierras de Córdoba topography is in a
Acknowledgements
We thank two anonymous reviewers for their comments on a draft of this paper. Also, we appreciate the support from the FonCyT, Argentina and SECyT, UNC, Argentina as well as PUE 2016 CICTERRA CONICET, Argentina for funding our studies. H. Canelo appreciates the support from the Universidad Nacional de Córdoba during his graduate studies in geology. Also, thanks to Dr. Federico Esteban for the support in GMT-mapping software of Wessel and Smith (1998).
References (118)
- et al.
The Plio-Quaternary uplift of the Apennine chain: new data from the analysis of topography and river valleys in Central Italy
Geomorphology
(2008) - et al.
Is the exhumation of the Sierras Pampeanas only related to Neogene flat-slab subduction? Implications from a multi-thermochronological approach
J. S. Am. Earth Sci.
(2013) - et al.
Response of a landscape to tectonics using channel steepness indices (ksn) and OSL: a case of study from the Jalisco Block, Western Mexico
Geomorphology
(2014) - et al.
Holocene activity and seismogenic capability of intraplate thrusts: insights from the Pampean Ranges, Argentina
Tectonophysics
(2018) - et al.
Distinguishing between tectonic and lithologic controls on bedrock channel longitudinal profiles using cosmogenic 10Be erosion rates and channel steepness index
Geomorphology
(2014) - et al.
Dynamic uplift during slab flattening
Earth Planet. Sci. Lett.
(2015) - et al.
Tectonic and dynamic controls on the topography and subsidence of the Argentine Pampas: the role of the flat slab
Earth Planet. Sci. Lett.
(2010) - et al.
The Achala Batholith (Córdoba, Argentina): a composite intrusion made of five independent magmatic suites. Magmatic evolution and deuteric alteration
J. S. Am. Earth Sci.
(1996) - et al.
Present-day South American climate
Palaeogeogr. Palaeoclimatol. Palaeoecol.
(2009) Andean subduction styles and their effect on thermal structure and interplate coupling
J. S. Am. Earth Sci.
(2002)
Links between topography, erosion, rheological heterogeneity, and deformation in contractional settings: insights from the central Andes
Tectonophysics
Quaternary deformation, river steepening, and heavy precipitation at the front of the Higher Himalayan ranges
Earth Planet. Sci. Lett.
Thermochronometric data on the development of the basement peneplain in the Sierras Pampeanas, Argentina
J. S. Am. Earth Sci.
Expression of active tectonics in erosional landscapes
J. Struct. Geol.
The relief of the Swiss Alps and adjacent areas and its relation to lithology and structure: topographic analysis from a 250-m DEM
Geomorphology
Early Cretaceous alkaline volcanism of the Sierra Chica de Córdoba Argentina: mineralogy, geochemistry and petrogenesis
J. S. Am. Earth Sci.
Calc-alkaline arc granitoid activity in the Sierra Norte-Ambargasta Ranges, central Argentina
J. S. Am. Earth Sci.
Cambrian to Devonian geologic evolution of the Sierra de Comechingones, Eastern Sierras Pampeanas, Argentina: evidence for the development and exhumation of continental crust on the proto-Pacific margin of Gondwana
Gondwana Res.
Crustal structure of the Eastern Sierras Pampeanas of Argentina using high frequency local receiver functions
Tectonophysics
The Pampean flat-slab of the Central Andes
J. S. Am. Earth Sci.
Stable isotope composition of middle Miocene carbonates of the Frontal Cordillera and Sierras Pampeanas: Did the Paranaense seaway flood western and central Argentina?
Palaeogeogr. Palaeoclimatol. Palaeoecol.
River profiles along the Himalayan arc as indicators of active tectonics
Tectonophysics
TecDEM: a MATLAB based toolbox for tectonic geomorphology, part 1: drainage network preprocessing and stream profile analysis
Comput. Geosci.
TecDEM: a MATLAB based toolbox for tectonic geomorphology, part 2: surface dynamics and basin analysis
Comput. Geosci.
Time scales of tectonic landscapes and their sediment routing systems
Geol. Soc. Lond., Spec. Publ.
Geomorphology of paleosurfaces in the Sierras de Comechingones, Central Pampean Ranges, Argentina
Cubierta sedimentaria paleozoica superior
Cubierta sedimentaria cenozoica (Paleógeno – Neógeno)
Spatial distribution of earthquakes and subduction of the Nazca plate beneath South America
Geology
Atlas climático digital de la República Argentina
Las precipitaciones en el Noroeste Argentino
Recursos Uraníferos
Orographic barriers, high-resolution TRMM rainfall, and relief variations along the eastern Andes
Geophys. Res. Lett.
Rise and fall of the southern Santa Cruz Mountains, California, from fission tracks, geomorphology, and geodesy
J. Geophys. Res. Solid Earth
Sierras Pampeanas de Catamarca, Tucumán, La Rioja y San Juan
Geomorfología de la Sierra Norte Ambargasta, provincias de Córdoba y Santiago del Estero, Argentina
Landscape antiquity of the Central Eastern Sierras Pampeanas Argentina: geomorphological evolution since Gondwanic times
Z. Geomorphol. Suppl.
Geomorfología
Tectónica Cuaternaria en las Sierras Pampeanas
Late Holocene faulting in the southeast Sierras Pampeanas of Argentina
Geology
Morfo neotectónica del frente de levantamiento andino de la sierra de Comechingones
Quaternary intraplate deformation in the southeastern Sierras Pampeanas, Argentina
J. Seismol.
Neotectónica
Quantifying rock uplift rates using channel steepness and cosmogenic nuclide–determined erosion rates: examples from northern and southern Italy
Lithosphere
Exhumation history of the Andean broken foreland revisited
Geology
Miocene forebulge development previous to broken foreland partitioning in the southern Central Andes, west central Argentina
Tectonics
Foreland basin systems
Basin Res.
Cyclical orogenic processes in the Cenozoic central Andes
Geol. Soc. Am. Mem.
Tectonic and lithologic controls on bedrock channel profiles and processes in coastal California
J. Geophys. Res. Earth Surf.
Shuttle Radar Topography Mission produces a wealth of data
EOS Trans. Am. Geophys. Union
Cited by (6)
Crustal focal mechanisms in the NW sierras de cordoba, and connections with mio-pliocene basement thrusting of the easternmost Sierras Pampeanas, south-Central Andes
2022, Journal of South American Earth SciencesCitation Excerpt :The footwall of the Pocho Sierra thrust sheet, along the Chancaní Valley (Fig. 4), is represented by a large, W-vergent, asymmetric synformal fold (drag fold) formed by Upper Paleozoic sedimentary rocks (Martino et al., 2016). The main fault scarp of the Sierra de Pocho thrust is affected by triangular facet, retrogradation by erosion, showing different knickpoints (Canelo et al., 2019), that together with alluvial and colluvial deposits bounding fault traces suggest neotectonic or Quaternary activity (Castaldi et al., 2021) (Fig. 3). This suggests an Active Deformation Front (ADF) and can be considered as the Main Morphogenic Fault (MPF, defined by Costa, 1999; García and Davis, 2004; see Fig. 4).
Triassic-Jurassic thermal evolution and exhumation of the western Gondwana foreland: Thermochronology and basalt thermobarometry from the Argentine Sierras Pampeanas
2021, Journal of South American Earth SciencesIn-service 80-year-old arch-gravity dam (Córdoba, Argentina): state of concrete conservation and potential development of the alkali-silica reaction
2024, Journal of Building Pathology and RehabilitationQuaternary activity associated with the Santa Catalina fault between the eastern piedemont and plain of the Comechingones mountain range, Sierras Pampeanas of Córdoba, Argentina.
2022, Revista de la Asociacion Geologica Argentina