Revista de la Asociación Geológica Argentina 61 (4): 461-479(2006) 461

AN OVERVIEW OF THE MAIN QUATERNARY DEFORMATION OF SOUTH AMERICA

Carlos H. COSTA1, Franck A. AUDEMARD M.2, Francisco H. R. BEZERRA3, Alain LAVENU4, Michael N. MACHETTE5 and Gabriel PARÍS6

¹Departamento de Geología, Universidad Nacional de San Luis, Chacabuco 917, 5700 San Luis, Argentina. Email: [email protected] 2FUNVISIS, Apartado Postal 76.880, Caracas 1070-A, Venezuela. Email: [email protected] 3Departamento de Geologia, Universidade Federal do Rio Grande do Norte, Natal, RN, 59072-970, Brazil. Email: [email protected] 4Institut de Recherche pour le Développement (IRD-LMTG - UR 154 - UMR 5563 - UPS, Toulouse 3), 14 Avenue Edouard Belin, 31400 Toulouse, France. Email: [email protected] 5 Earth Surface Processes Team, United States Geological Survey, MS 980, Box 25046, Denver, CO 80225, USA. Email: [email protected] 6 Departamento de Geografia, Universidad del Valle, Meléndez, Cali, Colombia, Email: [email protected]

RESUMEN: Una perspectiva sobre las principales deformaciones cuaternarias de América del Sur. Las deformaciones que han afectado al sector continental de Sudamérica durante el Cuaternario aparecen vinculadas con los procesos geo- dinámicos dominantes durante el Neógeno. Las mismas están principalmente controladas por las anisotropías heredadas de una prolon- gada y compleja historia evolutiva y por las características cinemáticas y geométricas que caracterizan a la interacción actual de placas. Las principales características de la tectónica cuaternaria en los extremos norte y sur de Sudamérica, derivan en forma directa de las interac- ciones entre bordes de placas, constituyendo muchos de estos rasgos estructurales los límites entre las mismas. A lo largo de la costa Caribe las principales estructuras con actividad durante el cuaternario exhiben principalmente una orientación E-O y régimen transcurrente. Entre los Andes venezolanos y el golfo de Guayaquil predominan estructuras con orientación NE y una cinemá- tica variable entre regimenes transcurrentes, transpresivos y compresivos. En los Andes Centrales (4ºS-46º30'S) la mayoría de las deformaciones cuaternarias resulta de una compleja distribución y partición de esfuerzos en el interior de la placa Sudamericana, reactivando discontinuidades preexistentes. La expresión superficial de este tipo de defor- maciones está mejor representada en la pendiente oriental andina y sectores adyacentes del antepaís. Aquí, la geometría actual de la sub- ducción de la placa de Nazca representa el principal control respecto a la distribución y características de las deformaciones cuaternarias. La principal estructura con actividad cuaternaria en el sector andino austral, está representada por un borde transformante con compo- nente sinestral en Tierra del Fuego, resultante de la interacción entre las placas de Sudamerica y de Scotia.

Palabras clave: América del Sur, deformaciones cuaternarias, neotectónica.

ABSTRACT Deformation affecting continental South America during Quaternary is related to the Neogene geodynamic processes. These structures are mainly controlled by anisotropies inherited after a long and complex history as well as by the kinematic and geometric features of the ongoing plate interaction. Main Quaternary structures at both ends of South America are directly linked to plate interaction and some of them are considered to be plate boundaries. The main structures with Quaternary activity along the Caribbean coast have an E-W trend and a strike-slip regime. Between the Venezuelan Andes and the Gulf of Guayaquil, NE trending structures are dominant, with a kinematic regime ranging from strike-slip to transpressive and compressive. At the Central Andes (4ºS-46º30'S) most Quaternary deformation results from a complex stress distribution and stress-partitioning at the inte- rior of the South American plate, reactivating preexisting discontinuities. The present geometry of the subducted Nazca plate is here the main control with respect to the distribution and characteristics of Quaternary deformation, being them better exposed at the Andean eastern slope and foreland regions. The main structure with Quaternary activity at the southernmost Andes is represented at Tierra del Fuego by a left-lateral transform boun- dary, resulting from the South American and Scotia plate interaction.

Keywords: South America, Quaternary deformation, Neotectonics.

INTRODUCTION ce of recent deformation for seismic-ha- bution by geological sciences to these criti- zard analysis and other applications has cal issues. Seismicity has traditionally been During the last two decades the significan- often been highlighted as a relevant contri- used to characterize some potentially hazar-

0004-4822/02 $00.00 + $00.50 C 2006 Revista de la Asociación Geológica Argentina 462 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

dous faults, especially along active plate ma- cesses that have occurred since Miocene- pondence with morphotectonic features. In rgin settings. However, faulting events rela- Pliocene times (perhaps as much as 25 areas where structures portray long recu- ted to recent earthquakes have shown that Myr). In order to provide a more specific rrence intervals and very slow slip rates, much of the deformation away from active time frame to "neotectonics" and despite faults with the shortest elapsed time since plate margins occurs along faults with no the problems outlined above, this article the last rupture (those considered most significant level of modern seismicity and will focus on the Quaternary tectonics of "active"), might not be the most hazard- that only a fraction of Quaternary faults are South America. This time interval is more ous in terms of seismogenic capability characterized by ongoing seismicity. Most suitably considered to include 1). features (Machette 2000, Costa 2004). Thus, the well of the seismic hazard in continental South resulting from the active (modern) stress engrained term "active fault" is not consi- America (inboard from the subduction zo- field; 2) structures related to recent/ dered suitable and could even be misleading ne) is related to shallow intraplate crustal ongoing topographic changes or mountain in terms of objective and homogeneous seismicity. Thus, developing information on building and 3) structures that have produ- mapping legends and accurate outreach. Quaternary faulting should help extend the ced earthquakes in the past and have the Accordingly, characterizing deformation short time span provided by records of his- capability of producing earthquakes in the based on the time since the last-recorded torical and instrumental seismicity into pre- future, thus posing a threat in terms of seis- fault slip (i.e., faults with late Quaternary, historic time (i.e., the late Quaternary). This mic hazard. Holocene or Historic displacement) is con- longer time span would allow making better Except for a few cases, there are little relia- sidered more suitable than characterization assessments of seismic potential and iden- ble information on slip rates, kinematics as active, capable, potentially active, inactive tifying the likely spatial and temporal distri- and paleoseismic record for South Ame- fault, and so on. This time-based categori- bution of future damaging earthquakes. rican faults. However, three main categories zation allows some flexibility in reporting The state of knowledge of Quaternary de- of slip rates can be established from the among different tectonic settings or coun- formation in South America is neither ho- tectonic setting and some recent results de- tries owing to the differing complexities or mogeneous nor complete. In most cases rived from GPS data (Freymueller et al. levels of investigation and abilities to date the information is of a reconnaissance na- 1993, Kellog and Vega 1995, Norabuena et prehistoric faulting events. ture, largely based in remote- sensing inter- al. 1998, Bevis et al. 2001, Kendrick et al. pretation and general fieldwork. Many 1999, 2001, Weber et al. 2001, Pérez et al. HISTORICAL SCOPE faults have slip rates that are lower than 2001, Brooks et al. 2003): sedimentation and/or erosion rates. Consi- Slip rates higher than 5 mm.yr-1: These occur The development of systematic and regio- dering that neotectonic analysis is com- on faults related to onshore plate-interac- nal neotectonic studies in South America is monly based on geomorphic features that tion, such as the Boconó fault system in quite recent. Except for specific reports may be related to recent deformation, this Venezuela and probably the Magallanes- spurred by earthquakes having surface de- kind of approach may identify more inacti- Fagnano fault zone in Chile-Argentina, or formation and other reconnaissance studies ve features than active ones. Therefore, dis- on subduction zones megathrusts such as for critical facilities, there are few references tinguishing between active control and pas- the type commonly located off the western to mapping Quaternary deformation on a sive control of structures in the landscape coast of South America. regional basis (see for example, Saint is crucial for successfully identifying a fea- Slip rates between 1-5 mm.yr-1: These occur on Amand and Allen 1960, Arabasz 1968, ture with Quaternary activity. faults related to stress-partitioning or to Okada 1971, Soulas 1978, Iriondo and The other issue which hampers a reliable major tectonic-terrane boundaries (i.e, Cor- Suguio 1981, Lavenu 1981, Sébrier et al. and accurate neotectonic analysis is the li- dillera Blanca -Peru-, Atacama -Chile-, El 1982, Lavenu 1986). Venezuela has been mited knowledge of Quaternary chronolo- Tigre-Argentina-, Ibagué -Colombia-, Oca- the leading country in developing regional gies. Regional temporal analyses rely on the Ancón -Venezuela). neotectonic maps starting in the early 1980s recognition of morphostratigraphic units, Slip rates lower than 1 mm.yr-1: These occur on (Schubert 1979, 1980a, 1980b, 1982, 1984, which are commonly vaguely referred to as most intraplate faults within the interior of Soulas 1986). At the same time, internatio- Quaternary, such as piedmont deposits or South America. nal projects such as IGCP 202 and IGCP landforms, alluvial deposits, basin fill sedi- There is no general agreement about when 206 promoted studies of many Quaternary ment, etc. a fault should be considered "active" and faults of South America. The term ¨neotectonics¨ has a floating time most definitions put forth are based on the Also in the mid-1980s the Preliminary frame, even in the specific literature tectonic setting, type of study and type of Neotectonic Map of South America was (Mercier 1976, Fairbridge 1981, Vita Finzi data available, and/or the author´s percep- compiled under the framework of the 1987, Hancock 1988, Pavlides 1989, tion of the problem. Moreover, geologic SISRA Project (González-Ferrán 1985), Mörner, 1994), as well for different inter- scenarios of Quaternary deformation vary being the first contribution of this type. pretations in South America. For some it is from very active plate boundaries to vir- This map depicted Quaternary faults, al- synonymous to "Quaternary Tectonics", tually stable cratonic areas, where instru- though with a strong bias toward seismo- whereas for others it refers to tectonic pro- mental seismicity generally has little corres- logy. An overview of the main quaternary deformation of South America 463

The launching of the International Lithos- with the aim of achieving homogeneous sent plate tectonic setting, cause a wide phere Program II-2 (World Map of Major mapping. A considerable part of the com- variety of neotectonic deformation in Active faults) during the 1990s (Trifonov pilation presented in this article is based on terms of both styles and geographical oc- and Machette 1993), provided a more ambi- information resulting from that decade- currences. tious effort to develop digital country or long effort. At a continental scale, South American neo- regional maps and inventories of Quater- tectonics is characterized by a dominance nary faults for the Andean countries and GENERAL TECTONIC SETTING of E-W trending strike-slip faulting at the Brazil (Audemard et al. 2000, Costa et al. northernmost and southernmost ends 2000a, Lavenu et al. 2000, París et al. 2000, As a response to complex, contemporary owing to plate interactions. On the other Saadi et al. 2002, Egüez et al. 2003, Macharé geodynamical processes, the distribution of hand, Quaternary deformation is fueled by et al. 2003). When this project was comple- neotectonic strain is not homogeneous in different and variable sources such as strain ted, Costa et al. (2003) undertook further continental South America and accordingly release related to subduction in a large part development of a dynamic, computer data- Quaternary deformation is concentrated of its western border and crustal weaknes- base. The ILP II-2 Project meetings allo- along the more than 8.000 km of the An- ses in intraplate and stable continental wed many researchers with different back- dean orogen (Fig. 1). The patterns and dis- regions. grounds to meet and discuss common ap- continuities of the Andes orogen, which The main areas of recent faulting and fol- proaches for studying active deformation are inherited from a long and complex evo- ding have been ascribed to the Andean re- along a wide variety of tectonic settings, lution and terrane history as well as the pre- gion including adjacent foreland regions and intraplate extra- Andean South Ame- rica. The Andes have traditionally been di- vided into three main sectors, namely the Northern Andes, the Central Andes and the Southern Andes (Auboin et al. 1973, Gansser 1973, Zeil 1979, Ramos 1999 and many others) (Fig. 1). Quaternary fault systems juxtaposing the bounding area between the Northern An- des and continental South America from the Caribbean coast to the Gulf of Gua- yaquil (Fig. 2) show slip rates higher than mm.yr-1 and a clear association with histori- cal seismicity. Along the Central Andes, the main cons- traint for grouping and describing Quater- nary deformation is the subducting geo- metry of the Nazca plate. The western slo- pe and coastal areas are direct manifestation of interplate processes and seismicity at the Benioff zone. Related megathrusts are offs- hore, whereas onshore evidence of Quater- nary tectonics are mostly related to coastal tectonics and a few large structures that are being driven by strain partitioning. At most retroarc areas and at the eastern slope of the Andes, major Quaternary structures are related to crustal weaknesses rather than to interplate processes and crus- tal seismicity does not necessarily image Quaternary deformation. Subduction zone segments with a normal subduction angles show noticeable diffe- rences in Quaternary occurrence and tecto- Figure 1: Main neotectonic settings and geotectonic features of continental South America and surrounding areas. 1. Northern Andes; 2. Central Andes; 2A. Peruvian flat-slab; 2B. Normal nic style than adjacent flat-subduction seg- subduction segment; 2C. Pampean flat-slab. ments. Quaternary deformation is more 464 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

Figure 2: Sketch of main Quaternary deformation along the Northern Andes displaying the follo- wing fault and fold systems: 1. Boconó; 2. Oca-Ancón; 3. San Sebastián; 4. El Pilar; 5. Los Bajos-El Soldado; 6. Tacagua- El Avila; 7. San Simón; 8. La Victoria; 9. Eastern Cordillera frontal fault; 10. Santa Marta- Bucaramanga; 11. Ibagué; 12. Algeciras; 13. Romeral; 14. San Isidro-El Angel- Otavalo; 15. Chingual; 16. Payamino-Sumaco- Pusuno-Arajuno; 17. Quito-Nagische- Latacunga-Yanayacu; 18. Pallatanga; 19. Naranjal-Ponce Enríquez; 20. Trench constrained to the Andean orogen in the Andes is dominated by a complex interac- by the rapid convergence of the South former and more efficiently transmitted to tion between the South American, Caribbe- American and Nazca plates (Fig. 2). the foreland region in the latter (see for an, and Nazca plates. Quaternary deforma- Eastward motion of the Caribbean plate example, Jordan et al. 1983a, 1983b, tion is largely concentrated along mountain relative to South America drives Quater- Gutscher et al. 2000). chains with the dominating structures being nary tectonics along northern Venezuela In contrast, little is known about the Qua- reverse and strike slip-faults (Pérez and (from Colombia to Trinidad) and determi- ternary tectonics of the Southern Andes. Aggarwal 1981, Schubert 1982, 1984, nes the dominant strike-slip complex regi- The main tectonic settings are here related Lavenu et al. 1995, Singer and Audemard me of the Oca-Ancón fault system. Ho- to oceanic-ridge subduction and a trans- 1997, Audemard et al. 2000, Taboada et al. wever a significant part of this dextral slip form interaction between the South Ame- 2000, Audemard and Audemard, 2002, seems to be currently distributed along the rica and Scotia plates. Audemard et al., this volume, Lavenu, this 1200 km-long fault system comprised of In extra-Andean South America, structures volume) the Boconó, San Sebastián, El Pilar, Los with Quaternary activity are generally loca- The NE and E-trending megafaults such as Bajos, and El Soldado faults and their sou- ted on pre-existing shear zones or weaknes- the Boconó-San Sebastián-El Pilar fault thern connections through the Gulf of ses. They typically have very long recurren- system in Venezuela (Schubert 1979, 1980a Guayaquil (Pérez and Aggarwal 1981, ce intervals, although recent studies have and 1980b), the Eastern Cordillera frontal Schubert 1980a,b, 1982, Stephan 1982, highlighted their capability of producing fault zone in Colombia (Pennington, 1981) Aggarwal 1983, Schubert 1984, Soulas surface ruptures as well as liquefaction (Be- and the Dolores-Guayaquil megashear 1986, Beltrán and Giraldo 1989, Singer and zerra et al. 1998, Riccomini and Assumpção (Campbell, 1974) (Fig. 2) are considered to Audemard 1997, Audemard et al. 2000, 1999, Bezerra and Vita Finzi 2000). comprise the long boundary that detaches Audemard and Audemard 2002, Audemard the Northern Andean Block from the et al. 2005, Audemard et al., this volume) QUATERNARY DEFORMA- remainder of South America. In fact, the (Fig. 2). This major strike-slip fault system TION ALONG THE ANDES Nor-thern Andes block is bounded by an concentrates the highest slip rates (around AND ADJACENT AREAS active right-lateral fault system and dextral 10 mm/yr) along northern South America, motion along these regional faults transla- as such; many authors have proposed that QUATERNARY DEFORMATION AT ted into compressional motion where the this fault system constitutes the current THE NORTHERN ANDES faults have a N-S trend; they all accommo- plate boundary between the South America The geology and tectonics of the Northern date E-W compressional stresses produced and Caribbean plates. This would imply that An overview of the main quaternary deformation of South America 465

most part of the Northern Andes is struc- The continued eastward subduction of the Andean region of the upper Amazon basin. turally detached from the South American Nazca plate beneath Colombia induces The first order onshore Quaternary tecto- plate (Hess and Maxwell 1953, Schubert most of the deep seismicity along the Wa- nic features in the Northern Andes of E- 1979, Aggarwal 1983, Soulas 1986 and dati-Benioff zone (Case et al. 1971, cuador are related to the geometry of the many others). However, this major issue is Londsdale and Klitford 1978, Pennington subduction zone and kinematics involved in still a matter of debate (Audemard et al., 1981, Gutscher et al. 2000, Taboada et al. plate interactions. Both the morphostructu- this volume). 2000). Therefore, southeastward and flat- ral regions and Quaternary faults appear to In particular, the right-lateral Boconó fault slab subducting geometry of the Caribbean be controlled by conspicuous NNE-SSW has a sinuous trace that traverses the Mérida plate (Kellogg et al. 1983) beneath the nor- trending Quaternary fault systems that are Andes in Venezuela (Fig. 2), and is flanked thern margin of Colombia defines the so- acting partially along ancient regional sutu- on both sides by a series of low-angle called Bucaramanga flat-slab with low asso- re zones. This part of the Andes represents thrusts (Audemard 1999). This configura- ciated seismicity (Ramos 1999). Southward a region where the subducting Nazca Plate tion attests to active strain or stress par- of 3°N, the main Quaternary deformation dips at 35°E. Nevertheless, detailed E-W titioning in this chain (Audemard and and related landforms of the Eastern Cor- cross-sectional profiles of seismicity show a Audemard 2002). Some second-order faults dillera frontal fault system are translated more complex behavior of the slab that are diverging or oblique to this major into a dominant strike-slip regime through (Gutscher et al. 1999). southern Caribbean fault system are inter- the Algeciras fault system (Velandia et al. The tectonic regime of the coastal region preted as synthetic Riedel shears, such as 2005), which extends across the Gulf of shows deep imprints of the subduction of the Tacagua-El Avila, Tácata and La Guayaquil. the Carnegie Ridge and the oblique conver- Victoria (Audemard et al. 2000, 2005, this The interaction of the Nazca, Caribbean gence of the Nazca Plate (Gutscher et al. volume). and South American plates causes striking 1999). Thus, normal and reverse faults The right-lateral motion related to the regional differences in the patterns and bound small blocks to the east of the Car- Boconó fault system is transferred south- style of Quaternary faulting. For example, negie Ridge, whereas a transpressional fault ward as a complex thrust and strike-slip the principal compressive-stresses in Co- system (Naranjal and Ponce Enríquez system into the different strands of the lombia are NW oriented in the northern faults) (Fig. 2) borders the northern coastal Eastern Cordillera frontal fault system Andean region and oriented E to NE in the ranges and the uplifted Western Cordillera, (Paris et al. 2000, Audemard and Audemard southern Andean region. By acting on defining an active fore-arc basin (Egüez et 2002). This foreland fold-and-thrust belt faults that trend N-S (i.e., major faults), al. 2003). overrides the ancient Llanos shield and has these stresses induce left-lateral movement The eastern structural limit of the Western shallow, but moderate-to-high levels of on the faults located to the north and right- Cordillera oceanic terrain in Ecuador ex- seismicity (Aggarwal 1983, Paris and Sarria lateral movement on faults located to the tends along the western border of the 1986, Robertson 1989, Sarria 1990, AIS south in both the Western and Eastern Inter-Andean Valley via the San Isidro, El 1996, Audemard 1999, Paris et al. 2000). Andean regions. In addition, reverse and Ángel and Otavalo faults (Egüez et al. There is a general agreement that the normal displacement takes place as a result 2003). Soulas et al. (1991) have interpreted Caribbean plate movement (Jordan 1975, of oblique compression (Paris and Romero this fault system as the southern extension Sykes et al. 1978, Duncan and Hargraves 1994, Paris et al. 2000). of the Romeral fault system. 1984) and the southeastward accretion of The Romeral fault system (McCourt et al. Field observations suggest that the main the Panama-Choco block (Duque-Caro 1983, Hutchings et al. 1981) extends along Quaternary fault systems are oblique to the 1980) are the main driving processes of the western slope of the Central Cordillera Ecuadorian Andes, starting at the Gulf of the contemporary tectonics in Colombia in Colombia (Fig. 2). It separates accreted Guayaquil (Pallatanga fault) and cutting (Kellogg and Vega 1995, Paris et al. 2000, oceanic rocks to the west from a domain of northeastward across the ranges toward the Audemard and Audemard 2002). In this continental rocks with associated crustal eastern border of the Real Cordillera sense, Taboada et al. (2000) have proposed seismicity to the east. Audemard et al. (Chingual fault) in northern Ecuador that a continental wedge with eastward in- (2005) have proposed that the change of (Soulas et al. 1991, Ego et al. 1995, Ego and dentation bounded by the Santa Marta- slip along strike of this major N-S-trending Sébrier 1996, Ego et al. 1996). These two Bucaramanga fault to the NE and by the fault partly results from strain partitioning main NE-trending faults show significant Itsmina-Ibagué faults to the south cause along a curved subduction front. strike-slip morphology and right-lateral ongoing thrusting at the Eastern Cordillera North of the Gulf of Guayaquil, the Ecua- kinematic indicators, and correspond to the front as well as transpressive deformation dorian Andes comprise five main morphos- southern extension of the Eastern Cordi- at the Santander Massif in Colombia. Wi- tructural regions from west to east: 1) the llera frontal fault system in Colombia. They thin this framework, the Santa Marta-Bu- Coastal Plain, 2) Western Cordillera, 3) are probably responsible for the main crus- caramanga fault displays Quaternary mor- Interandean Valley (also called the Inter- tal earthquakes recorded historically in photectonic features (Paris and Sarria 1986) Andean Tectonic Depression), 4) Real Ecuador (Fig. 2). related to sinistral movement (Fig. 2). Cordillera and, 5) Andean foothills or sub- Between the Pallatanga and Chingual faults, 466 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

the slip motion is accommodated by minor NE-SW-trending oblique faults and by N-S fault zones along the Inter-Andean Valley, where folds, flexures, and related reverse faults (including the Quito fault and asso- ciated Nagsiche, Latacunga and Yanayacu anticlines) have been mapped (Lavenu et al. 1995, Egüez et al. 2003, Lavenu, this volu- me). The sub-Andean zone (Napo and Cutucu foothills) lies at the eastern margin of the Andean Range and western border of the upper-Amazon basin. This zone includes folded Mesozoic sedimentary rock boun- ded by thrust systems with significant Neo- gene and Quaternary displacement, such as the Payamino, Sumaco, Pusuno and Ara- juno faults (Iglesias et al. 1991, Egüez et al. 2003).

QUATERNARY DEFORMATION AT THE CENTRAL ANDES (4ºS-46º30'S)

The Central Andes are considered to be a typical Andean-type orogen, where moun- tain building has been driven primarily by subduction processes through the collision of the Nazca and the South American pla- tes (Ramos 1999). The Central Andes re- present more than 4000 km of the Andean chain, encompassing a wide variety of Quaternary tectonic styles and settings. Figure 3: Sketch of main Quaternary deformation along the Central Andes, including the They are commonly divided into the Peruvian flat-slab segment (4°-14°S) and the normal subduction segment (14°-27°S). The fold and fault systems referred in the text are: 1. Shitari; 2. Chaquilbamba; 3. Quiches; 4. Cordillera Northern, Central, and Southern sectors Blanca; 5. Huaytapallana; 6. Cuzco; 7. Incapuquio; 8. Escoma-Achacachi-Peñas-Kenko; 9. Beni; (Ramos 1999). 10. Mande-Yapecua; 11. Lomas de Olmedo; 12. Atacama; 13.Trench. In a diverse array of tectonic styles and set- tings, the main controllers of the distribu- The description of Quaternary tectonic been described onshore, which highlight tion and style of Quaternary deformation features in the Central Andes are grouped the vertical component of subduction rela- appear to be the current subduction regime and described as follows: ted processes and crustal elastic respon- and the inherited geological history. The Peruvian flat-slab (4°S - 14°S) se along the Peruvian flat-slab sector characteristics and occurrence of Quater- Normal subduction segment (14°S - 27°S) (Macharé and Ortlieb 1992). nary deformation follow in a broad sense Pampean flat-slab (27°S-33°S) The resulting overthickening of the crust this general division, having a strong corre- Central Andes south of 33°S gave rise to the Cordillera Blanca uplift, lation between the distribution and charac- which has some of the highest elevations in teristics of the deformation and the geo- THE PERUVIAN FLAT-SLAB the Andes and where Quaternary normal metry of the subducting Nazca plate. (4°S - 14°S) faults are associated with recent surface Although the western piedmont of the faulting (Bonnot 1984, Bonnot et al. 1988, Andes and coastal regions are closest to the This sector exhibits a temporal migration of Schwartz 1988, Macharé et al. 2003) (Fig. 3). epicenters of large subduction-related deformation toward the foreland (to the Also, it is important to note that shallow earthquakes, there are just few examples of east) as a result of flat-slab subduction geo- seismicity characterizes the Eastern Cor- Quaternary faulting onshore, with their oc- metry during the past 5 Ma (Sébrier and dillera and the sub-Andean zone (Suárez et currence much better developed and docu- Soler 1991, Sébrier et al. 1988, Gutscher et al. 1983, Dorbath et al. 1991) where active mented at the morphostructural units loca- al. 2000). Uplifted marine terraces are a- deformation is dominated by fault-related ted eastward. mong the few deformed features that have folds such as the Shitari fault system and An overview of the main quaternary deformation of South America 467

other unnamed structures (Macharé et al. thick-skinned basement-cored uplifts of the on the nearly 800-km-long Atacama fault 2003). Cordillera Oriental, and low angle thrusts (Fig. 3). This fault probably represents the The most significant Quaternary deforma- and fault-related folds at the sub-Andean most significant geomorphic imprint of tion reported so far in Peru is located along thin-skinned fold-and-thrust belt. Quaternary deformation at the fore arc. Its this flat-slab sector where historic surface Geomorphic evidence of recent tectonic varying kinematic signatures have inspired ruptures have occured along the Chaquil- activity with different geometries and kine- different interpretations including right- bamba and Quiches faults (Silgado 1951, matics have been reported between the lateral (Saint Amand and Allen 1960, Doser 1987, Bellier et al. 1989, 1991, Coastal Cordillera and the western pied- Arabasz 1968, Okada 1973, Dewey and Macharé et al. 2003), whereas seismicity is mont of the Western Cordillera, north and Lamb 1992), left-lateral (Armijo and Thiele ongoing along the Huaytapallana fault zone south of the Arica elbow in Perú and Chile 1990), and normal faulting (Delouis et al. (Macharé et al. 2003). There is outstanding (Muñoz and Charrier 1996, Jacay et al. 2002, 1998, Lavenu et al. 2000, Lavenu this volu- morphogenetic expression of the Cordi- González et al. 2003, Audin et al. 2003, this me). llera Blanca fault (Bonnot 1984, Schwartz et volume, Allmendinger et al. 2005). Quaternary deformation and related state al. 1984, Bonnot et al. 1988, Schwartz 1988) The NNW-trending Incapuquio fault sys- of stress of the Transversal Cordillera (bet- as well as good geomorphic expression of tem (Jacay et al. 2002, Audin et al., this volu- ween 18°S and 22°S) is still poorly docu- both normal and reverse faults in southern me) located at the western piedmont of the mented. Peru along the Cuzco and other fault sys- Western Cordillera has reactivated old tec- The uplift of the Altiplano-Puna plateau tems (Sébrier et al. 1985, Macharé et al. tonic structures and is associated with has been thermally induced (Froidevaux 2003) (Fig. 3). thrust-related folds, strike-slip faults and nor- and Isacks 1984). It has a mean elevation of One of the most distinctive tectonic ex- mal faults that extend about 200 km over 3800 m, but lies below the Western and pressions of flat-lying subduction at the the Western Cordillera piedmont (Fig. 3). Eastern Cordillera. The Central Altiplano, Pampean segment of the Central Andes, is The coastal ranges in Peru exhibit normal which was the more subsiding region in the the development of broken foreland uplifts faults trending perpendicular to the coast, Cenozoic, is characterized by important between 27° S and 33° S (the Sierras Pam- whereas in northern Chile reverse or nor- continental sedimentation. Faults and folds peanas in Argentina) (Jordan et al. 1983a,b). mal faults trend obliquely to the coast resulting from Neogene compressive An- However, no similar features with associa- (González et al. 2003, Allmendinger et al. dean tectonics affect this entire region ted Quaternary activity have been described 2005). (Lavenu and Mercier 1991, Mercier et al. so far in the Peruvian flat-slab. In the northern part of the Chilean Andean 1992). In addition, during the Quaternary, fore arc, the Pampa de Tamarugal repre- the Altiplano has been affected by N-S ex- THE NORMAL SUBDUCTION sents a young tectonic depression (also tensional tectonics that can be related to the SEGMENT OF THE CENTRAL known as the Northern Central Depression effect of high topography (Sébrier et al. ANDES (14°S - 27°S) or Longitudinal Valley) which morphologi- 1985). A side effect of this process has cally separates the Coastal Range from the been basinal collapse and associated lands- This segment is underlain by normal sub- Precordillera. Extensional tectonics does liding along these and other piedmont duction with a sharp change in subduction not seem to have played a role in the forma- faults (Lavenu et al. 2000). This deforma- angle at its northern end and a smooth tran- tion of the Central Depression (Reutter et tion is responsible for important normal sition to a flat-slab sector to the south al. 1988) in contrast to coastal marine terra- faults with a cumulative displacement of (Barazangi and Isacks 1976, Chinn and ces that are affected by E-W extensional more than 400 m near the city of La Paz Isacks 1983). The Central Andes at these deformation. (Lavenu et al. 2000). latitudes, particularly between 14°S and Andean subduction in Chile is characteri- The Eastern Altiplano, which forms the 20°S are the widest part of the Andean zed by a general oblique convergence vec- western piedmont of the Eastern Cordi- chain (as much as 600 km). From west to tor with respect to the plate boundary. The llera, is bounded on the east by a major fault east, the main morphostructural Andean different ways this oblique convergence is zone (Escoma, Achacachi, Peñas and units in Peru, Bolivia, Chile and Argentina accommodated and their links with resul- Kenko fault zones in Fig. 3) that forms the are composed of the Pacific Coast (which ting Quaternary features is still not well escarpment of this Cordillera (Lavenu includes the offshore Perú-Chile trench, the understood (Lavenu et al. 2002). Onshore 1981, Lavenu and Mercier 1991, Lavenu et Coastal Cordillera and the Central Valley), uplift is demonstrated by elevated Quater- al. 2000). The tectonic basin occupied by the Western Cordillera, the Altiplano-Puna nary marine terraces suggesting Quaternary Lake Titicaca is controlled by these normal plateau, the Eastern Cordillera and the sub- uplift rates from 0.2 to 0.6 mm.yr-1 (Ortlieb faults and is one of the consequences of N- Andean zone. et al. 1996, Marquardt et al. 2004, 2005, S Quaternary extension (Lavenu 1992). Quaternary deformation is represented by Lavenu this volume). In those coastal areas Quaternary deformation affecting Quater- high-angle normal faults in internally drai- (23ºS-27ºS) about 100 km to the east of the nary bajadas and other alluvial surfaces and ned plateaus such as the Puna and Alti- trench, the stress regime during the late resulting from different stress regimes has plano, high-angle reverse faults along the Pleistocene is reflected by E-W extension been reported from the Altiplano south to 468 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

the end of the Puna plateau (Palma and pected that important Quaternary deforma- suggested that the Beni River is currently Vujovich 1987, Cortés et al. 1987, tion and seismic potential must be related being deflected northward by the north- Allmendinger et al. 1989, Allmendnger and to thrust faults and growing anticlines trending Beni fault (Fig. 3). Gubbels 1996, Lavenu et al. 2000). (Stein and Yeats, 1989) along the sub-An- The Eastern Cordillera has been an area of dean region (here including the Sierras THE PAMPEAN FLAT-SLAB uplift during the entire Cenozoic (Sebrier et Subandinas and Santa Bárbara ranges). One (27°S-33°S) al. 1988, Mon 1993). Neogene deformation of the most important historic Argentinean of the Cochabamba and Tarija basins and earthquakes (Talavera de Esteco, 1692) Quaternary deformation above the Pam- other places in Bolivia has been reported occurred in this region (Salta province); pean (Chilean) flat-slab is better exposed at (Lavenu et al. 2000). In Argentina, base- Castano and Zamarbide (1978) calculated a the eastern Andean slope. This latitudinal ment-related deformation gave rise to faults magnitude of 7.3 for this historic event. section concentrates more than 90 percent and folds in Neogene strata and sometimes The forest cover has hampered recognition of the Quaternary deformation currently Quaternary sediment, but without strong of all but the most prominent morphoge- documented in Argentina (Costa et al. geomorphic evidence of Quaternary acti- nic Quaternary structures, although Ramos 2000a) which is particularly prominent at its vity (Mon 1976). et al. (2003, this volume) reported signifi- southern half (30°S-33°S). Quaternary de- The sub-Andean lowlands fold-and-thrust cant evidence of this style of Quaternary formation includes historic surface ruptu- belt constitutes an Andean orogenic front deformation at the Lomas de Olmedo fault ring on La Laja fault during the 1944 Mw that has been dominated by contraction system (Fig. 3). 7.0 San Juan (Castellanos 1944, Groeber since the Neogene (Baby et al. 1989, 1992, To the north, the Beni foreland basin is 1944, Harrington 1944) the 1977 Mw 7.4 Dumont 1996). Pleistocene deposits are located northeast and east of the Bolivian Caucete earthquakes on the Ampacama- thrusted along the Mandeyapecuá fault Andean chain in front of the sub-Andean Niquizanga fault (Volponi et al, 1978, (Moretti et al. 1996) (Fig. 3), and thus could fold-and-thrust belt. As with other foreland Bastías 1985) (Fig. 4), as well as the more confirm recent deformation along the oro- basins, the Beni basin is a flexural basin that significant historical and instrumental seis- genic front. In Argentina, it has been sus- is presently subsiding. Dumont (1996) has mic events. The reported concentration of Quaternary structures on the flat-slab sub- duction segment matches the observation that seismic energy released in the upper plate is on average 3 to 5 times greater than in sectors with normal subduction angles (Jordan et al. 1983a,b, Smalley et al. 1993, Gutscher et al. 2000, Ramos et al. 2002). As a result of the eastward migration of the Andean orogenic front during the Neogene, orogenic activity during Pliocene- Pleistocene is evidenced by the rise of the Precordillera fold-and-thrust belt (Ramos 1988). The active Andean front and main Quaternary structures are currently located between its eastern foothills and the wes- ternmost Sierras Pampeanas (Fig. 4) (Bastías et al. 1984, 1990, 1993, Cortés et al. 1999, Costa et al. 2000a, 2000b). The Quaternary structures have overprinted previous structures in both the Precordille- ra and Sierras Pampeanas. The Western and Central Precordillera north of 32°S behave as a thin-skinned thrust belt with east-verging (Andean-type) thrusts. The Eastern Precordillera exhibits basement-cored, west-verging (Pampean- type) thrusts, and has been defined as a Figure 4: Sketch of the main Quaternary fault and fold systems developed on the Pampean flat- slab. 1. El Tigre; 2. Villicum-Zonda-Pedernal; 3. La Laja-Marquezado-La Rinconada-Cerro thick-skinned triangle zone by Zapata and Salinas; 4. Ampacama-Niquizanga; 5. Las Peñas-Las Higueras. Morphostructural expression of Allmendinger (1996). If one considers the Precordillera within dashed lines. mainly tectonic heritage, the styles of Qua- An overview of the main quaternary deformation of South America 469

ternary deformation of the Precordillera Precordillera (Zapata and Allmendinger coseismic vertical slip larger than 1m (Costa along the Andean front and seismic belt can 1996) seems to vanish south of Las Peñas and Vita Finzi 1996, Costa et al. 2001). be divided in two sections-north and south River (32°30' S), instead blind thrusts and Thus, the seismic capability of these faults of 32°S. growing anticlines that have evolved from seems to be much more relevant than sug- North of 32°S, evidence of Quaternary inverted Triassic basins are recognized both gested by the seismic catalog. tectonics is concentrated mainly along the at surface and at depth to the southern end Pliocene-Pleistocene-uplifted Eastern Pre- of the Precordillera (33°S) (Triep 1987, THE CENTRAL ANDES SOUTH OF Cordillera. This morphostructure exhibits a Brooks et al. 2000, Chiaramonte et al. 2000) 33°S main west-bounding thrust fault (Villicum- and as far south as 34°S (Polanski 1963, Zonda-Pedernal thrust), although the most Kozlowsky et al. 1993, García et al. 2005). South of 33°S the subudction of the Nazca impressive Quaternary deformation is at The striking change in style and concentra- plate is characterized by a normal subduc- the eastern backslope of this range. The tion of Quaternary deformation marks the tion angle and a narrow Andean orogenic deformation is represented by rectilinear hinge area between the flat-lying and nor- belt. The transition with the Quaternary and parallel fault traces that are coincident mal-subduction segments. Epicentres of deformation located north of 33°S is cha- with bedding planes in pre-Quaternary historic earthquakes as well as northward racterized by blind thrusting and different rocks as backlimb tightening-type structu- deviation of the Mendoza River at 33°S types Quaternary faults at the Frontal Cor- res. This deformational pattern has been (Ortiz and Salfity 1989) may suggest that dillera and southernmost Precordillera foo- interpreted as resulting from a distributed ongoing deformation at this latitude has thills (Polanski 1963, Regairaz and Videla flexural-slip faulting type, rather than the shifted eastwards to the foreland from the Leaniz 1968, Bastías et al. 1993, Tello 1994, expression of primary rupture surfaces main outcropping thrusts and is now being Cortés and Sruoga 1998, Chiaramonte et al. (Costa et al. 1999, Krugh and Meigs 2001, expressed through a west-verging Pam- 2000, Koslowsky et al. 1993, Cortés et al. Meigs et al., this volume). The La Laja, pean-type blind thrust in its initial stage of 1999, Brooks et al. 2000, García et al. 2005). Marquezado, La Rinconada, Los Berros and development and landscape imposition During the Quaternary, deformation has Cerro Salinas faults (Bastías et al. 1987, (Costa et al. 2006). been partitioned into two states of stress 1990, Martos 1987) are the most significant The Sierras Pampeanas of Argentina are south of 32°S (Lavenu and Cembrano structures showing this style of deforma- generally regarded as the broken foreland 1999, Lavenu et al. 2000). In the fore-arc sli- tion (Fig. 4). adjacent to the Andean orogen and as a ver (Costal Cordillera, Central Depression, The rectilinear trace and Holocene mor- main morphotectonic expression of flat- and part of the Main Cordillera), compres- phology of El Tigre strike-slip fault is cle- slab subduction (Jordan et al. 1983a,b). sive deformation along N-S trends, is recor- arly seen along at least 200 km of the wes- They may well be modern equivalents of ded by reverse faults (San José de Maipo, tern slope of the Precordillera fold-and- the Laramide-age Rocky Mountain foreland Esperanza, and Victoria faults east from thrust belt (Bastías et al. 1984, 1987, 1990, uplifts in the Western United States (Jordan Santiago and southeast from Concepción) Bastías 1985, Bastías and Bastías 1987, and Allmendinger 1986). These basement (Lavenu et al. 2000, 2002, this volume). Bastías and Uliarte 1987, Siame et al. 1997a, blocks have been uplifted and tilted during At the intra-arc, the Liquiñe-Ofqui fault 1997b, 1998, 2002, 2005) (Fig. 4). As a con- the past 8-5 Myr (Ramos et al. 2002) and system (Hervé 1976, Hervé and Thiele sequence of stress partitioning at this latitu- theirs morphostructural evolution has been 1987, Cembrano et al. 1996) is at the sou- de, this fault is the main Quaternary struc- linked with the development of the Pam- thern Central Andes a prominent neotecto- ture that releases the longitudinal (N-S) pean flat-slab and with the Andean building nic feature that suggests Quaternary stress component of continental plate motion. ever since, thus involving Quaternary de- partitioning (Fig. 5). Trans-pressive NE-SW Although this is a striking and major fault, formation more than 600 km away from the deformation occurred during the Pleisto- its slip rates are likely below 1 mm.yr-1 trench. These blocks commonly are boun- cene along this fault system (Lavenu and (Siame et al. 1997). ded by west-verging reverse faults that dip Cembrano 1999, Lavenu, this volume). South of 32°S at the southern Precordillera 30°-55°E. Such marginal faults are usually Local changes from transpresive to trans- in Mendoza province, major Quaternary located along the western hillslopes and tensive regimes along its trace have been deformation is transferred to emerging or constitute the Neogene uplifted front of reported on the basis of the trend of reac- blind east-verging thrusts (Las Peñas and the ranges. Quaternary deformation has tivated faults (Lavenu, this volume). The Las Higueras thrusts (Fig. 4), Cortés and been reported along many of them northern growth of this fault system into Costa 1996, Cortés et al. 1999, Costa et al. (Massabie 1987, Costa 1999, Costa et al. the eastern Andean slope in Argentina has 2000b, Costa et al. 2006), many of which 2000a, and many others). been proposed by Folguera et al. (2004), evolved from inverted normal faults of a It is commonly understood that these typi- thus constituting the modern orogenic Triassic rift (Ramos and Kay 1991, Dellape cal intraplate faults have long recurrence front between 36°S and 38°S (the Antiñir- and Hegedus, 1995). The thick-skinned intervals. However, recent studies have sug- Copahue fault zone of the Guañacos fold- triangular zone that characterizes the inter- gested that prehistoric earthquakes have and-thrust belt) (Fig. 5). action between the Eastern and Central ruptured to the surface, probably with This part of the Andes generate the largest 470 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

instrumentally recorded earthquake in the In the Fueguian Andes at the southern tip world (the Mw 9.5, 1960 Chilean Earth- of South America, a striking change in the quake); although with an offshore epicenter pattern of Quaternary deformation is cau- this event determined uplift and subsidence sed by the interaction of the South Ameri- along large parts of south-central Chile can and Scotia plates, giving rise to a domi- (Saint-Amand 1963, Plafker and Savage nance of strike-slip faulting on Tierra del 1970, Atwater et al. 1992, Cifuentes 1989, Fuego Island (Winslow 1982, Winslow and and many others). Even forty years after Prieto 1991, Klepeis 1994, Lodolo et al. this event, GPS measurements indicate that 2003, Smalley et al. 2003). Two Ms 7.8 the crust is still adjusting to this sudden earthquakes that occurred on December strain release (Kendrick et al. 1999). 17th, 1949, caused surface ruptures along This and other ancient mega-thrust earth- the Fagnano-Magallanes fault (Fig. 6), quakes have left their imprints in coastal which is considered to be the onshore terraces rather than as noticeable onshore expression of this plate-transform boun- ruptures. However, the role of uplifted te- dary. rraces in illuminating the record of pre- Geologic investigations (Schwartz et al. vious earthquakes has proved to be elusive. 2001, 2002, Costa et al. this volume) near The complications related to differential Fagnano Lake have documented 1-2 m of preservation of evidences and temporary normal coseismic slip with an undetermi- reversals in the sense of movement have ned (submetric) amount of left-lateral been addressed by Atwater et al. (1992) and movement. The secondary strike-slip com- Vita Finzi (1996). ponent fits the interpretation that Lago Rock-avalanches and landslides seem to be Fagnano is in a transtensive section of this the remaining evidence of secondary and major fault system (Lodolo et al. 2003). off-fault effects of large prehistoric earth- Figure 5: Main trace of Liquiñe-Ofqui Fault Zone quakes that were not necessarily associated EXTRA ANDEAN SOUTH (LOFZ) and the Antiñir-Copahue Fault System with surface ruptures in the Andes between AMERICA (ACFS). Both right-lateral strike-slip systems are 36°S and 38°S (González Díaz et al. 2006, partitioning the deformation at these latitudes Hermanns et al. 2003, Costa and González Except for some areas in Brazil, Quaternary (modified from Folguera et al 2004). Díaz, in press). deformation along this intraplate region nally continuous linear features in cratonic (which is larger than the entire Andean and pericratonic areas may result from the QUATERNARY DEFORMATION AT Cordillera) is poorly studied and not well passive imposition of long-lived structures THE SOUTHERN ANDES (46° 30'S- documented. Neogene structures, particu- commonly enhanced by fluvial systems. 55°S) larly those with Quaternary activity or the Conversely, subtle linear features and anoma- capacity for future movement, have long lies in river patterns in Quaternary basins The southern Andes extend south of the recurrence intervals (5 kyr to 100 kyr or might evolve from the ongoing propagation Triple Junction that links the subduction of more). This is because they do not reflect of brittle subsurface structures with slip rates the Chile rise with the interaction of the direct plate interaction, but instead reflect much lower than the sedimentation rate. The South America, Nazca, and Antarctica pla- low-strain rate reactivation of previous ani- interpretation as to whether or not these fea- tes (Figs. 1 and 6). Little is known about the sotropies and structures (sometimes very tures have Quater-nary activity is often a mat- Quaternary tectonics between the Gulf of old) under the present stress regime after a ter of controversy due to the lack of diagnos- Penas (46°30' S) and the Tierra del Fuego. long cycle of stress loading. tic data (Peulvast et al. IN PRESS) datable The rugged terrain and dense forest cover As demonstrated in other "stable" continental materials, or natural exposures. on the western slope have so far prevented regions, surface deformation can occur at For continental extra-Andean South Ame- paleoseismic research other than image unexpected locations, even those without rica, Riccomini and Assumpção (1999) have interpretation and general reconnaissance noticeable seismicity and/or late Quaternary divided it into the Brazilian and Patagonian surveys. Neogene deformation is partitio- faulting (Crone et al. 1997, 2003). In these platforms, the former being composed of ned through strike-slip structures at the regions, Quaternary rates of deformation are Archean to Proterozoic cratons, Neopro- forearc and a fold-and-thrust belt along the considerably lower (and probably well below terozoic orogenic belts, and Phanerozoic eastern foothills of continental South A- 0.1 mm/yr) than prevailing erosion or depo- sedimentary basins. The latter includes ex- merica, where Neogene deformation has sition rates, thus resulting structures have only tra-Andean Patagonia as well as the Pam- been documented (Ramos 1989, Kraemer a slight chance of imposing their geomorphic pean and surrounding regions cored by the 1993) but no Quaternary structures have signatures into the landscape assemblages as a Pampia craton. been specifically studied. result of faulting. Macroscale and even regio- In the Brazilian platform, several examples An overview of the main quaternary deformation of South America 471

tion features and geodetic anomalies. Structures affecting Quaternary deposits often correspond to reactivated fault planes with a long history of both reactivation phases and stress regimes. The contempo- rary continental stresses result in E-W to WNW-ESE shortening along the Atlantic coast, although several changes in stress regimes have been documented during the Quaternary (Riccomini and Assumpção 1999, Saadi et al. 2002). Also, recent apatite fission-track dating suggests a significant rate of crustal uplift since the Miocene (Nóbrega et al. 2005). A record of Quaternary deformation is Figure 6: Location of the Jundiaí present in several craton-related basins, and Boa Cica faults, which affect such as the Amazonas, Pantanal and Paraná Neogene sedimentary units; (C) basins (Iriondo and Suguío 1981, Riccomini epicenters that illuminate the Samambaia fault. and Assumpção 1999, Saadi et al. 2002, 2005). However, the two areas where Qua- ternary deformation has been well docu- mented are the Borborema region in nor- theastern Brazil and along the Serra do Mar rift system (Sao Paulo and Rio de Janeiro States). In the state of Rio Grande do Norte in northeastern Brazil, raised marine terraces record coastal uplift and submer- gence during the Quaternary. Tectonic dif- ferential coastal uplift and subsidence, in excess of that predicted by glacioisostaic models, have been suggested (Barreto et al. 2002) because part of the data can not be explained by eustatic variations alone. Liquefaction features in Quaternary alluvial gravel and gravelly sediment have been des- cribed at the Potiguar basin area. These fea- tures are linked to historical earthquakes as well as to paleoseismicity, accounting for paleomagnitudes of about M 6.8 (Bezerra and Vita-Finzi 2000, Bezerra et al. 2005, this volume). Among the most significant faults in terms of Quaternary deformation, the Jundiaí and Boa Cica faults (Fig. 7) record Holocene displacements, the former having a cumulated vertical slip of approximately 260 m on Miocene deposits (Barreiras Formation) (Bezerra and VitaFinzi, 2000, Figure 7: Map of NE Brazil and location of faults discussed in text: a) Map of the west part of Bezerra et al. 2001, this volume). The trace the Potiguar basin and main faults; b) location of the Jundiaí and Boa Cica faults, which affect of the NE-trending Samambaia fault (Fig. Neogene sedimentary units; c) epicenters that illuminate the Samambaia fault. 7) shows prominent seismicity near the of Quaternary tectonics have been repor- this volume, Saadi et al. 2002, 2005, Bezerra village of João Câmara (Takeya et al. 1989, ted, particularly in the past two decades and Vita-Finzi 2000, and many others). Bezerra et al., this volume), illustrating one (Riccomini et al. 1989, Assumpção 1992, These cases include not only surface ruptu- of the few cases where a fault is imaged by Saadi 1993, Bezerra et al. 1998, 2001, 2005, res but also for development of liquefac- seismicity in intraplate areas. 472 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

At the Serra do Mar, several Quaternary Chingual and Pallatanga faults in Ecuador), transform boundary between the South structures have been described as affecting transpressive, and even compressive types America and Scotia plates. It constitutes a the Cenozoic basins related to the conti- of movements (the Eastern Cordillera well expressed linear feature on a regional nental rift (Riccomini 1989, and many frontal fault system in Colombia). scale, with left-lateral motion predicted others cited in Riccomini and Assumpção Along the Central Andes, the traces and from modern plate kinematics and docu- 1999). These structures mainly represent distribution of structures with Quaternary mented by GPS studies. the reactivation of previously active struc- activity are less continuous and less well For extra-Andean South America, much tures having a general NE-SW trend. They organized. The Pacific coastal region and progress in neotectonics has been made record different stress regimes acting du- the western Andean piedmont are the clo- during the last two decades, particularly at ring the Quaternary in that region. The few sest areas to large offshore subduction the coastal regions in Brazil. Here, Quater- reports on Quaternary deformation on the earthquakes. However, Quaternary defor- nary activity has been documented on faults Pampean plains and in extra-Andean Pata- mation is not represented by prominent that have reactivated previous discontinui- gonian regions have commonly noted local fault zones (except for the Atacama fault in ties or fault zones, as well as the discovery features having only secondary evidence or Chile), but raher through emerging or sub- of secondary phenomena related to Qua- tectonic origins (Quattrocchio et al. 1994, siding areas instead. ternary faulting. Structures in these type of Sagripanti et al. 1999, Brunetto 2005, 2006, The style and characteristics of Quaternary stable continental settings commonly have Mon et al. 2005, and Rosello et al. 2005). tectonics at the surface are mainly the con- short traces compared with Andean struc- sequences of different geometries of the tures and are commonly linked to Mesozoic CONCLUDING REMARKS subducting angle of the Nazca plate. rift zones or even older crustal weaknesses. Therefore, along the Central Andes, parti- Except for the primary Quaternary faults in Quaternary deformation in South America cularly north of 33°S, the subducting plate the Northern Andes of Venezuela and Co- is concentrated along the Andean Cordi- can be grouped into different segments. At lombia, most Quaternary structures in con- llera and adjacent regions, whereas defor- the Peruvian flat-slab segment (4°S-14°S) tinental South America are developed mation has been sparsely documented in both normal and reverse faulting have been within an intraplate domain. Here, inherited the extra-Andean regions. The inherited documented, some of them as short traces discontinuities and their relations with the structural discontinuities and ongoing plate with associated historical ruptures and o- present stress regime seem to influence the interactions are the main controls on the thers as main bounding structures of high time span of their seismic cycles much distribution, geometry, and kinematics of mountain ranges such as the Cordillera more than do distant interplate interactions. Quaternary deformation. At both ends of Blanca fault. Due to the long recurrence intervals inhe- continental South America, major Quater- At the normal subduction segment of the rent in the seismic cycles of intraplate nary structures have formed principally Andes between 14°S and 27°S Quaternary structures (103-105 years), they may not be from plate interactions with strike-slip regi- faulting has been described along the imaged by seismicity, but still have proven mes, whereas Quaternary deformation Peruvian and Chilean coastal areas, where seismogenic capability. The recent devasta- along the Central Andes (4°S-46°30'S) is the Atacama fault system stands out. Qua- ting earthquake in Gujaratj, India (almost basically compressional and related to sub- ternary deformation is represented across 20,000 deaths), the 1812 New Madrid duction of the Nazca plate. The influence the Andes by high-angle normal faults at earthquakes in the USA, and lesser but illus- the style and distribution of structures with the Puna and Altiplano plateaus; high-angle trative surface-faulting earthquakes in Aus- Quaternary activity is strongly influenced reverse faults along the Cordillera Oriental, tralia (Crone et al. 2003) show that many by the subduction angle and the resulting and thin-skinned thrusts at the sub-Andean stable continental interior regions are not interaction with the overriding South A- zone. so stable. Thus, information on Quater- merican plate. The Pampean flat-slab segment of the Cen- nary faulting and surface deformation Quaternary structures along the Northern tral Andes (27°S-33°S) concentrates Qua- would add significant data for expanding Andes are the most continuous and of con- ternary deformation along the orogenic the record of historical and instrumental tinental scale. Most of these faults have slip front at the eastern foothills of the Precor- seismicity and for developing more realistic rates higher than 1 mm.yr-1 and are com- dillera. This deformation is also distributed assessments of the seismic capability posed monly associated with shallow crustal seis- across the Andean foreland through block by a structure. This in turn, would help to a micity. Through a complex geometric and uplifts of the Sierras Pampeanas where better understanding on the likely spatial kinematic framework, these structures ac- most of their bounding reverse faults have and temporal distribution of future dama- commodate and transfer ongoing stresses undergone activity during the Quaternary. ging earthquakes. resulting from the interaction of the Carib- Except for a few structures, the Quaternary bean and South America plates. These deformation south of 33°S is poorly docu- ACKNOWLEDGEMENTS structures have strike-slip movement (i.e. mented. In southernmost South America at Oca-Ancón, San Sebastián, Los Bajos El Tierra del Fuego island, the Magallanes- We thank all the colleagues that collabora- Soldado and Boconó fault in Venezuela, Fagnano fault is an onshore E-W-trending ted with the ILP Project "World Map of An overview of the main quaternary deformation of South America 473

Major Active faults". We are also indebted Audemard, F. A. 1999. Morpho-structural ex- Yee, M, Paiva, R. and Munita, C. 2002. Late to V. Ramos and M. Sébrier for constructi- pression of active thrust fault systems in the Pleistocene marine terrace deposits in nor- ve reviews. O. Pedersen, H. Cisneros and E. humid tropical foothills of Colombia and theastern Brazil: sea- level change and tecto- Ahumada helped with the graphics. Venezuela. Zeitschrift für Geomorphologie nic implications. Palaeogeography, Palaeocli- 118: 1-18. matology, Palaeoecology179 (1-2): 57-69. WORKS CITED IN THE TEXT Audemard, F. E. and Audemard, F. A. 2002. Bastías, H. 1985. Fallamiento Cuaternario en la Structure of the Mérida Andes, Venezuela: región sismotectónica de Precordillera. PhD Aggarwal, Y. 1983. Neotectonics of the relations with the South America-Caribbean Thesis, Universidad Nacional de San Juan Southern Caribbean: Recent Data, new ideas. geodynamic interaction. Tectonophysics 345: (inédita) 147 p., San Juan. Acta Científica Venezolana 34(1):17. 299-327. Bastías, H. 1990. Discontinuidades tectónicas a Allmendinger, R., Strecker, M., Eremchuk, J.E. Audemard, F. Machette, M., Cox, J., Dart, R. and la latitud de 32° sur y su importancia en las and Francis, P. 1989. Neotectonic deforma- Haller, K. 2000. Map and Database of hipótesis de evolución de Precordillera. 11° tion of the southern Puna Plateau northwes- Quaternary Faults in Venezuela and its Congreso Geológico Argentino, Actas 2: tern Argentina. Journal of South American Offshore Regions. U.S. Geological Survey 407-411. Earth Sciences 2 (2): 111-130. Open-File Report 00-018, 82 p. Bastías, H. and Bastías, J. 1987. Análisis de des- Allmendinger, R.W. and Gubbels, T. 1996. Pure Audemard, F. A., Romero, G. Rendon, H. and plazamientos y velocidades en el Area and simple shear plateau uplift, Altiplano-Pu- Cano, V. 2005. Quaternary fault kinematics Diferencial Precordillera. Revista Asociación na, Argentina and Bolivia. Tectonophysics and stress tensors along the southern Geológica Argentina 42: 261-266. 259: 1-13. Caribbean from microtectonic data and focal Bastías, H. and Uliarte, E. 1987. Morfología de la Allmendinger, R. W., Gonzalez G., Yu J., Hoke mechanism solutions. Earth-Science Reviews falla rumbo-deslizante El Tigre entre los ríos G. and Isacks B. 2005. Trench-parallel shorte- 69 (3-4): 181-233. Jachal y San Juan. 10° Congreso Geológico ning in the Northern Chilean Forearc: Audemard, F., Singer, A and Soulas, J-P. 2006. Argentino, Actas 1: 251-254. Tectonic and climatic implications. Geologi- Quaternary Faults and Stress Regime of Bastías, H., Weidmann, N. and Pérez, M. 1984. cal Society of America, Bulletin 117: 89-104. Venezuela, Revista Asociación Geológica Dos zonas de fallamiento Pliocuaternario en Arabasz, W.J. 1968. Geologic structure of the Argentina (this volume). la Precordillera de San Juan. 9° Congreso Tal-tal area, northern Chile, in relation to the Audin, L., Hérail, G,. Riquelme, R., Darrozes, J., Geológico Argentino, Actas 2: 329-341. earthquake of December 28, 1966. Bulletin Martinod, J. and Font, E. 2003. Geomor- Bastias, H., Uliarte, E., Paredes, J., Sanchez, A., of the Seismological Society of America 58: phological markers of faulting and neotecto- Bastias, J., Ruzicki, L. and Perucca, L. 1990. 835-842. nic activity along the western Andean margin, Neotectónica de la provincia de San Juan. 11° Armijo, R., and Thiele, R. 1990. Active faulting northern Chile. Journal of Quaternary Congreso Geologico Argentino, Relatorio: in Northern Chile-Ramp stacking and lateral Science 18(8): 681-694. 228-244. decoupling along a subduction plate boun- Audin, L., David, C., Hall, S., Farber, D. and Bastias, H., Tello, G., Perucca, L., and Paredes, J. dary? Earth and Planetary Science Letters 98: Hérail, G. 2006. Geomorphic evidences of 1993, Peligro sísmico y neotectónica, En 40-61. recent tectonic activity in the forearc, Ramos V. (ed.) Geología de la provincia de Asociación Colombiana de Ingeniería Sísmica Southern Peru, Revista Asociación Geológica Mendoza. 12° Congreso Geológico Argen- (AIS) 1996. INGEOMINAS-Uniandes, Es- Argentina (this volume). tino, Relatorio: 645-658. tudio general de la amenaza sísmica en Baby, P., Hérail, G., López, J.M., López, O., Oller, Bellier, O., Macharé, J. and Sébrier, M. 1989. Colombia: INGEOMINAS, Bogotá, 254 p. J., Pareja, J., Sempéré, T. and Tufiño, D. 1989. Extensión Actual Del Nor Perú: Estudio de Assumpção, M., 1992. The regional intraplate Structure de la Zone subandine de Bolivie : la Falla Activa de Chaquilbamba (Norte del stress field in South America. Journal of Influence de la géométrie des séries sédimen- Departamento de la Libertad, Perú. Boletín Geophysical Reseach 97: 11,889-11,903. taires antéorogéniques sur la propagation des Sociedad Geológica Perú 80:1-12. Atwater, B. F., Nuñez, H. J. and Vita-Finzi, C. chevauchements. Comptes Rendu Academie Bellier, O., Dumont, J.-F., Sébrier, M. and 1992. Net Late Holocene emergence despite des Sciences, Série 2, 309: 1717-1722. Mercier, J.-L. 1991. Geological constraints on earthquake-induced submergence, south- Baby, P., Hérail, G., Salinas, R. and Sempéré, T. the kinematics and fault-plane solutions of central Chile. Quaternary International 15/ 1992, Geometry and kinematic evolution of the Quiches fault zone reactivated during the 16: 77-85. passive roof duplexes deduced from cross 10 November 1946 Ancash earthquake, nor- Aubouin, J., Audebaud, E., Debelmas, J., Dollfus, section balancing-Example from the foreland thern Peru. Bulletin Seismological Associa- O., Dresh, J., Faucher, B., Mattauer, M., thrust system of the Southern Bolivian tion of America 81(2): 468-490. Mégard, F., Paredes, J., Savoyat, E., Thiele, R. Subandean Zone: Tectonics 11(3): 23-536. Beltrán, C. and Giraldo, C. 1989. Aspectos neo- and Vicente, J. C. 1973. De quelques problè- Barazangi, M. and Isacks, B. 1976. Spatial distri- tectónicos de la región nororiental de mes géologiques et géomorphologiques de la bution of earthquakes and subduction of the Venezuela. 7° Congreso Geológico Venezo- Cordillère des Andes. Revue de Géographie Nazca plate beneath South America. lano, Proceedings 3: 1000-1021. Physique et de Géologie Dynamique 2-15(1- Geology 4: 686-692. Bevis, M., Kendrick, E. Smalley Jr., R. Brooks, B. 2): 207-216. Barreto, A., Bezerra, F., Suguio, K, Tatumi, S., A. Allmendinger, R.W. and Isacks, B.L. 2001. 474 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

On the strength of interplate coupling and Cabrera, J, Sébrier, M. and Mercier, J-L. 1987. M., 1999. Tectónica Cuaternaria en la región the rate of back arc convergence in the cen- Active normal faulting in high plateaus of andina del nuevo Cuyo. En. R. Caminos tral Andes: An analysis of the interseismic central Andes: the Cuzco region (Peru). An- (Ed.). Geología Argentina. SEGEMAR Ana- velocity field. Geochemestry, Geophysics, nales Tectonicae 1-2: 116-138. les 29: 760-778. Geosystems 2, 10.129/2001GC000198. Campbell, C.J. 1974. Ecuadorian Andes in Me- Costa, C. 1999. Tectónica Cuaternaria en las Bezerra, F.H.R. and Vita-Finzi, C. 2000. How sozoic-Cenozoic orogenic belt, data for oro- Sierras Pampeanas. En Caminos, R. (ed.) active is a passive margin? Paleo-seismicity in genic studies. Geological Society of London Geología Argentina, SEGEMAR, Anales 29: northeastern Brazil. Geology 28: 591-594. Special Publication 4: 725-732. 779-784. Bezerra, F.H.R., Lima-Filho, F.P., Amaral, R.F., Case, J. E., Duran, L. G., Lopez, A. and Moore, Costa, C. 2004. Microtectónica en el Cuater- Caldas, L.H.O. and Costa-Neto, L.X. 1998. W. R. 1971. Tectonic investigations in Wes- nario? Métodos y aplicaciones de la Paleosis- Holocene Coastal tectonics in NE Brazil. In: tern Colombia and Eastern Panama. Geo- mología. Revista Asociación Geológica Ar- Stewart, I. and Vita-Finzi, C. (eds.): Coastal logical Society of America Bulletin 82: gentina, Publicación Especial 7: 9-19. Tectonics. Geological Society of London, 2685-2712. Costa, C. and Vita-Finzi, C. 1996. Late Holocene Special Publication 146: 279-293. Castano, J., and Zamarbide, J. 1978. Determina- intraplate faulting in the SE Sierras Pampea- Bezerra, F.H.R., Amaro, V.E., Vita-Finzi, C. and ción de coeficientes sísmicos zonales para la nas, Argentina. Geology 24: 1127-1130. Saadi, A. 2001. Pliocene-Quaternary fault República Argentina. Publicación Técnica 6, Costa, C. and González Díaz, E.F. 2006. Age control of sedimentation and coastal plain INPRES, 23 p., San Juan. constrains and paleoseismic implication of morphology in NE Brazil. Journal of South Castellanos, A. 1944. El terremoto de San Juan. rock-avalanches in the Northern Patagonian American Earth Sciences 14: 61-75. En Cuatro lecciones sobre terremotos, Andes, Argentina. Journal of South Ame- Bezerra, F.H.R., Amaral, R.F., Vita-Finzi, C., Asociación Cultural de Conferencias de rican Earth Sciences, in press. Lima-Filho, F.P. and Saadi, A. 2005. Lique- Rosario, p. 79-242, Rosario. Costa, C., Rockwell, T., Paredes, J. and Gardini, faction-induced structures in Quater-nary Cembrano, J., Hervé, F. and Lavenu, A. 1996. C. 1999. Quaternary deformations and seis- alluvial gravels and gravelly sediments, NE The Liquiñe Ofqui fault zone: a long-lived mic hazard at the Andean orogenic front Brazil. Engineering Geology 76: 191-208. intra-arc fault system in southern Chile. (31º-33º, Argentina): A paleoseismological Bezerra, F. H., Ferreira, J. and Souza, M., 2006. Tectonophysics 259: 55-66. perspective. 4º International Symposium on Review of seismicity and Neogene tectonics Chiaramonte, L., Ramos, V., and Araujo, M. Andean Geodynamics, Proceedings: 187-191. in northeastern Brazil. Revista Asociación 2000. Estructura y sismotectónica del anticli- Costa, C., Machette, M., Dart, R., Bastías, H., Geológica Argentina (this volume). nal Barrancas, cuenca Cuyana, provincia de Paredes, J., Perucca, L., Tello, G. and Haller, Bonnot, D. 1984. Néotectonique et Tectonique Mendoza. Revista Asociación Geológica Ar- K. 2000a. Map and Database of Quaternary Active de la Cordillére Blanche et du Callejón gentina 55: 309-336. Faults and Folds in Argentina. U. S. Geologi- de Huaylas, Andes Nord Peruviennes, PhD Chinn, D.S., and Isacks, B.L. 1983. Accurate cal Survey Open-File Report 00-0108, 75 p. Thesis Université d'Orsay, París. source depths and focal mechanisms of sha- Costa, C., Gardini, C. Diederix, H, and Cortés, J. Bonnot, D., Sébrier, M. and Mercier, J-L. 1988. llow earthquakes in western South America 2000b. The Andean thrust front at Sierra de Evolution geodynamique plio-quaternaire du and in the News Hebrides islands arc. Las Peñas, Mendoza, Argentina. Journal of basin intracordillerain du Callejón de Huaylas Tectonics 2: 529-563. South American Earth Sciences, 13: 287-292. et de la region de la Cordillére Blanche, An- Cifuentes, I. 1989. The 1960 Chilean earthquake. Costa, C., Murillo, V., Sagripanti, G. and Gardini, des Nord Peruviennes. Geodynamique 3: Journal of Geophysical Research 94(B1): C. 2001. Quaternary intraplate deformation 57-83. 665-680. in the southeastern Sierras Pampeanas, Ar- Brooks, B. A., Sandvol, E. and Ross, A. 2000. Cortés, J., and Costa, C. 1996. Tectónica Cuater- gentina. Journal of Seismology 5: 399-409. Fold style inversion: Placing probabilistic naria en la desembocadura del Río de las Pe- Costa, C., Cisneros, H., Machette, M. and Dart, constraints on the predicted shape of blind ñas, Borde oriental de la Precordillera de R. 2003. A new database of Quaternary thrust faults. Journal of Geophysical Re- Mendoza. 13° Congreso Geológico Argen- faults and folds in South America. ILP Task search 105: 13,281-13,302. tino, Actas 2: 225-238. Group II-2 (western Hemisphere). American Brooks, B.A., Bevis, M., Smalley, R.Jr., Kendrick, Cortés, J., and Sruoga, P. 1998. Zonas de fractu- Geophysical Union, Fall Meeting, San Fran- E., Manceda, R., Lauría, E., Maturana, R. and ra cuaternarias y volcanismo asociado en el cisco. Araujo, M. 2003. Crustal motion in the sou- piedemonte de la Cordillera Frontal (34°30' Costa, C., Gardini, C., Diederix, H., Cisneros, H. thern Andes (26°-36°S): do the Andes beha- LS), Argentina. 10° Congreso Latinoameri- and Ahumada, E. 2006. The active Andean ve like a microplate? Geochemestry, Geo- cano de Geología, Actas 2:116-121. orogenic front at the Souhternmost Pampean physics, Geosystems 4: 1-14. Cortés, J., Franchi, M., and Nullo, F. 1987. flat-slab. Backbone of the Americas. Abstract Brunetto, E. 2005. Mapa de Lineamientos Evidencias de neotectónica en las sierras de with Programs 15-1. Morfológicos de la cuenca inferior del Río Aguilar y del Tanque, Cordillera Oriental y Costa, C., Smalley Jr, R., Schwartz, D., Stenner, Dulce, Laguna Mar Chiquita y Bloque San Puna Jujeñas, Argentina, 10° Congreso Geo- H., Ellis, M. and Velasco, S. 2006. Paleoseis- Guillermo. 16° Congreso Geológico Argen- logico Argentino, Actas 1: 239-242. mic observations on an onshore transform tino, Actas 4: 545-552, La Plata. Cortés, J., Vinciguerra, P., Yamín, M. and Pasini, boundary: The Magallanes-Fagnano fault, An overview of the main quaternary deformation of South America 475

Tierra del Fuego, Argentina. Revista Asocia- since late Miocene time. Annales Tectonicae de su inducción por un mecanismo sísmico. ción Geológica Argentina (this volume). 10 (1-2): 31-59. Revista de la Asociación Geológica Argentina Crone, A.J., Machette, M.N. and Bowmam, J.R. Ego F., Sébrier M., Carey-Gailhardis E. and 61(2): 197-217. 1997. Episodic nature of earthquake activity Beate B. 1996. Do the Billecocha normal González Ferrán, O. 1985 Mapa Neotectónico in stable continental regions revealed by faults (Ecuador) reveal extension due to preliminar para América del Sur. SISRA Pro- palaeosiesmicity studies of Australia and lithospheric body forces in the Northern ject vol. 11 Series with Map, 110 p. North America Quaternary fault. Australian Andes? Tectonophysics 265 (3-4): 255-273. Groeber, P. 1944. Movimientos tectónicos con- Journal of Earth Sciences 44: 203-214. Ego F., Sébrier M. and Yepes H. 1995. Is the temporáneos. Universidad Nacional de La Crone, A. J., De Martini, P.M., Machette, M.N., Cauca-Patia and Romeral fault system left - Plata, Notas del Museo de La Plata, Geología and Okumura, K. 2003. Paleoseismicity of or right-lateral? Geophysical Research 9: 263-375. aseismic Quaternary faults in Australia- Letters 22. Gutscher, M.A., Malavieille, J., Lallemand, S., and Implications for fault behavior in stable con- Egüez, A., Alvarado, A., Yepes, H. Machette, M., Collot, J.Y. 1999. Tectonic segmentations of tinental regions. Bulletin of the Seismological Costa, C. and Dart, R. 2003. Database and the North Andean margin-An impact of the Society of America 93(5): 1913-1934. Map of Quaternary Faults and Folds in Carnegie Ridge collision. Earth and Planetary Dellapé, D., and Hegedus, A. 1995, Structural Ecuador and its Offshore Region. U.S. Geo- Science Letters 168: 255-270. inversion and oil occurrence in the Cuyo logical Survey Open-File Report 03-289, 77 p. Gutscher, M.-A., Spakman, W., Bijwaard, H. and basin of Argentina. In Tankard, A., Suárez Fairbridge, R. 1981. The concept of neotecto- Engdahl, E. R. 2000. Geodynamics of flat R., and Welsink, H. (eds.) Petroleoum basins nics: An introduction. Zeitschrift Geomor- subduction; seismicity and tomographic of South America, American Association of phologischen Beilband 40: 7-12. constraints from the Andean margin. Tec- Petroleum Geologists, Memoir 62: 359-367. Folguera, A., Ramos, V, Hermanns, R. and tonics 19(5): 814-833. Delouis B., Philip H., Dorbath L., and Cisternas Naranjo, J. 2004. Neotectonics in the foo- Hancock, P. 1988. Neotectonics. Geology Today A. 1998. Recent crustal deformation in the thills of the sothernmost central Andes (37°- 4: 57-61. Antofagasta region (Northern Chile) and the 38°S): Evidence of strike-slip displacement Harrington, H. 1944. Volcanes y terremotos. Ed. subduction process. Geophysical Journal along the Antiñir-Copahue fault zone. Tec- Pleamar, 251 p. International 132: 302-338. tonics 23, TC 5008, 23. Hermanns, R.L., González Díaz, E.F., Folguera, Dewey, J., and Lamb, S. 1992. Active tectonics of Freymueller, J.T., Kellogg, J.N. and Vega, V. 1993. Andrés and Mardones, M. 2003. Large massi- the Andes. Tectonophysics 205: 79-95. Plate motions in the north Andean region. ve rock slope failures dams, related valley Dorbath, L., Dorbath, C., Jiménez, E. and Ri- Journal of Geophysical Research 98: 21853- evolution and their association with the tec- vera, L. 1991. Seismicity and tectonic defor- 21863. tonic setting in the Argentine and Chilean mation in the eastern Cordillera and Sub Froidevaux, C., and Isacks, B. 1984. The mecha- Andes between 36° and 38°S. 10° Congreso Andean zone of Central Perú. Journal of nical state of the lithosphere in the Altiplano- Geológico Chileno (Concepción), CD: 1-5. South American Earth Sciences 4: 13-24. Puna segment of the Andes. Earth and Hervé, M. 1976. Estudio geológico de la Falla Doser, D.I. 1987 The Ancash Peru earthquake of Planetary Science Letters 71: 305-314. Liquiñe-Reloncavi en el area de Liquiñe; ante- November 19, 1946-Evidence for low-angle Gansser, A. 1973. Facts and theories on the cedentes de un movimiento transcurrente normal faulting in the high Andes of nor- Andes. Journal of the Geological Society of (Provincia de Valdivia). 1° Congreso Geo- thern Peru. Journal of Geophysical Research London 129 (1): 93-131. lógico Chileno, B39-B56. 91: 57-71. García, V.H., Cristallini, E.O., Cortés, J.M., and Hervé, F. and Thiele, R. 1987. Estado de conoci- Dumont, J.F. 1996. Neotectonics of the Rodriguez, C. 2005. Structure and neitecto- miento de las megafallas en Chile y su signifi- Subandes-Brazilian craton boundary using nics of the Jaboncillo and Del Peral anticli- cado tectónico. Comunicaciones 38: 7-91. geomorphological data-The Marañon and nes: New evidences of Pleistocene to ¿Ho- Hess, H. and Maxwell, J. 1953. Caribbean Beni basins. Tectonophysics 257: 137-151. locene deformation in the Andean Piedmont. Research Project. Bulletin of the Geological Duncan, R.A. and Hargraves, R.B. 1984. Plate 6° International Symposium on Andean Society of America 64 (1): 1-6. tectonic evolution of the Caribbean regions Geodynamics, Extended Abstracts: 301-304, Hutchings, L., Turcotte, T. and McBride, J. 1981. in the mantle reference frame. In Bonnini, Barcelona. Microseismicity along the Dolores shear R.B., Hardgraves, R.B. and Shagan, R. (eds.) González, G., Cembrano, J., Carrizo, D., Macci, zone in Antioquia, Colombia. Seismological The Caribbean-SouthAmerican plate boun- A. and Schneider, H. 2003. The link between Society of America, 76th annual meeting, dary and regional tectonics, Geological forearc tectonics and Pliocene-Quaternary Earthquake Notes 52(1): 68-69. Society of America, Memoir 162: 81-84. deformation of the Coastal Cordillera, nor- Iglesias R., Eguez A. and Pérez V.H. 1991. Mapa Duque-Caro, H. 1980. Geotectónica y evolución thern Chile. Journal of South American Sismotectónico del Ecuador: Quito, Ecua- de la región noroccidental de Colombia. Bo- Earth Sciences 16: 321-342. dor, Dirección Nacional de Defensa Civil, letin Geológico INGEOMINAS 23(3): 4-37. González Diaz, E., Folguera, A., Costa, C., Memoria técnica 177 p. Ego F. and Sébrier M. 1996. The Ecuadorian Wright, E. and Ellisondo, M. 2006. Los gran- Iriondo, M.H., and Suguio, K. 1981, Neotec- inter-Andean valley; a major and complex des deslizamientos de la region septentrional tonics of the Amazon Plain: Bulletin of restraining bend and compressive graben neuquina entre los 36°-38°S: una propuesta INQUA, Neotectonic Commission 4: 72-78. 476 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

Jacay, J., Semperé, T., Husson, L. and Pino, A. 235-256. 367-370. 2002. Structural characteristics of the Inca- Kraemer, P.E. 1993. Perfil estructural de la Lodolo, E., Menichetti, M., Bartole, R., Ben- puquio Fault System, southern Peru. Ext- Cordillera Patagónica Austral a los 50° LS, Avraham, Z., Tassone, A., Lippai, H. 2003. ended Abstract, 5° International Symposium Santa Cruz. 12° Congreso Geológico Argen- Magallanes-Fagnano continental transform on Andean Geodynamics: 319-321. tino and 2° Congreso Exploración de Hidro- fault (Tierra del Fuego, southernmost South Jordan, T.H. 1975. The present-day motions of carburos, Actas 3: 119-125, Buenos Aires. America). Tectonics 22(6): 15.1-26. the Caribbean Plate. Journal of Geophysical Krugh, W.C., and Meigs, A. 2001. Secondary Lonsdale, P. and Klitford, K.D. 1978. Structure Research 80: 4433-4449. deformation associated with active base- and tectonic history of the eastern Panama Jordan, T., Isacks, B., Allmendinger, R., Brewer, ment-involved folding; Late Quaternary fle- Basin. Geological Society of America Bulle- J., Ramos, V., and Ando, C. 1983a. Andean xural-slip faulting and kink-band migration, tin 89: 981-999. tectonics related to geometry of subducted Sierra de Villicum, San Juan, Argentina. Macharé, J. and Ortlieb, L. 1992. Plio-Quater- Nazca plate. Geological Society of America Geological Society of America Abstracts nary vertical motions and the subductión of Bulletin 94: 341 361. with Programs 33: 393. the Nazca Ridge, central coast of Peru. Jordan, T.E., Isacks, B., Ramos, V.A. and Lavenu, A. 1981. Origine et évolution néotecto- Tectonophysics 205: 97-108. Allmendinger, R.W. 1983b. Mountain buil- nique du lac Titicaca. Revue Hydrobiologie Macharé, J., Fenton, C., Machette, M. Lavenu. A., ding in the Central Andes. Episodes 1983(3): Tropicale 14(4): 289-297. Costa, C. and Dart, R. 2003. Database and 20 26, Ottawa. Lavenu, A. 1986. Etude tectonique et néotecto- Map of Quaternary Faults and Folds in Perú Jordan, T., and Allmendinger, R. 1986. The nique de l'Altiplano et de la Cordillère orien- and its Offshore Region. U.S. Geological Sierras Pampeanas of Argentina-A modern tale des Andes boliviennes. ORSTOM, Tra- Survey Open-File Report 03-451, 55 p. analogue of Rocky Mountains foreland de- vaux et Documents microfichés, 28, 420 p., Machette, M. 2000. Active, Capable and Poten- formation. American Journal of Science 286: Paris. tially Active Faults- A paleoseismic perspecti- 737-764. Lavenu, A. 1992. Formation and geological evo- ve. Journal of Geodynamics 29: 387-392. Kellogg, J., Godley, V., Ropain, C., and lution. In Dejoux C. and Iltis A. (eds.) Lake Marquardt, C., Lavenu, A., Ortlieb, L., Godoy, Bermúdez, A. 1983. Gravity anomalies and Titicaca, Kluwer Academic Publisher: 1-13. E., and Comte, D. 2004. Coastal Neotecto- tectonic evolution of northwestern South Lavenu, A. 2006. Neotectónica de los Andes nics in Southern Central Andes: Uplift and America. 10th Caribbean Geological Con- entre 1°N y 47°S (Ecuador, Bolivia y Chile): deformation of marine terraces in Northern ference, Memoir: 18-31. una revisión. Revista Asociación Geológica Chile (27ºS). Tectonophysics 394(3-4): 193- Kellogg, J. and Vega, V. 1995. Tectonic develop- Argentina 61(4):, Buenos Aires. 219. ment of Panama, Costa Rica, and the Co- Lavenu, A. and Mercier, J.L. 1991. Evolution du Marquardt, C., Fornari, M., Lavenu, A., Vargas, lombian Andes: Constraints from Global régime tectonique de l'Altiplano et de la G., Ortlieb, L., Ritz, J. F., Philip, H. and Positioning System geodetic studies and gra- Cordillère Orientale des Andes de Bolivie du Marinovic, N. 2005. Volcanic ash dating from vity. Special Paper Geological Society of Miocène supérieur à l'Actuel. Géodynamique the Mejillones Peninsula (23°S). Implications America 295: 75-90. 6(1): 21-55. for the Neogene outer fore-arc stratigraphy, Kendrick, E., Bevis, M., Smalley, R.F. Jr., Lavenu, A. and Cembrano, J. 1999 Estados de tectonics and volcanic relationships. 6° In- Cifuentes, O. and Galbán, F. 1999. Current esfuerzo compresivo plioceno y compresivo- ternational Symposium on Andean Geody- rates of convergence across the Central transpresivo pleistoceno, Andes del sur, Chile namics, Proceedings: 477-480. Andes; estimates from continuous GPS (38- y 42°30' S). Revista Geológica de Chile Martos, L. 1987. Evidencias de movimientos observations. Geophysical Research Letters 26(1): 67-87. neotectónicos en una terraza de edad Ho- 26(5): 541-544. Lavenu, A., Winter, T. and Dávila, F. 1995. A locena, La Rinconada, San Juan. 10° Con- Kendrick, E., Bevis, M., Smalley Jr., R. and Pliocene-Quaternary compressional basin in greso Geológico Argentino, Actas 1: 263- Brooks, B. 2001. An integrated crustal velo- the Interandean Depression. Central 265. city field for the central Andes. Geochemistry Ecuador. Geophysical Journal International Massabie, A. 1987. Neotectónica y sismicidad en Geophysics Geosystems 2, 10.1029/ 121: 279-300. la región de Sierras Pampeanas Orientales, 2001GC000191. Lavenu, A., Thiele, R., Machette, M., Dart, R., sierras de Córdoba, Argentina. 10° Congreso Klepeis, K.A. 1994. The Magallanes and Bradley, L. and Haller, K. 2000. Maps and Geológico Argentino, Actas 1:271-274. Deseado fault zones: Major segments of the Database of Quaternary Faults in Bolivia and McCourt, W.J., Aspden, J.A. and Brook, M. 1984. South American-Scotia transform plate Chile, U.S. Geological Survey Open-File New geological and geochronological data boundary in southernmost South America, Report 00-283, 50 p. from the Colombian Andes; continental Tierra del Fuego. Journal of Geophysical Lavenu, A., Cembrano, J. and Costa, C. 2002. growth by multiple accretion. Journal of the Research 99:22,001-22,014. Margin-parallel v/s margin-orthogonal com- Geological Society of London 141(5): 831- Kozlowski, E., Manceda, R. and Ramos, V. 1993. presión along a convergent margin: The 845. Estructura. In Ramos, V. (ed.) Geología y Andes of Central-Southern Chile and Meigs, A., Krugh, W., Schiffman, C., Vergés, J. Recursos Naturales de Mendoza, 12° Western Argentina. 5º International Sympo- and Ramos, V. 2006. Refolding of thin-skin- Congreso Geológico Argentino, Relatorio: sium on Andean Geodynamics, Proceedings: ned thrust sheets by active basement-invol- An overview of the main quaternary deformation of South America 477

ved thrust faults in the eastern Precordillera Ortiz, A. and Zambrano, J. 1989. Estructuración de la Asociación Geológica Argentina 17: of western Argentina. Revista Asociación geológica profunda y expresión superficial: 127-349. Geológica Argentina (this volume). Ejemplos argentinos. 1° Congreso Nacional Quattrocchio, M., Kostadinoff, J., Martinez, G., Mercier, J. 1976. La néotectonique: Ses méthodes de Exploración de Hidrocarburos, Actas 2: and Prieto, A. 1994. Evidencias de neotectó- et ses buts. Revue Geographie Physique et 885-899. nica en el Río Sauce Chico, Provincia de Geologie Dynámique 18(2):323-346. Ortlieb, L., Zazo, C., Goy, J., Dabrio, C. and Buenos Aires. Revista de la Asociacion Geo- Mercier, J.L., Sébrier, M., Lavenu, A., Cabrera J., Macharé, J. 1996. Pampa del Palo: an anoma- lógica Argentina 49: 297-305. Bellier, O., Dumont, J.F., and Macharé, J. lous composite marine terrace on the upri- Ramos, V. 1988. The tectonics of the Central 1992. Changes in the tectonic regime above a sing coast of southern Peru. Journal South Andes; 30° to 33°S latitude. In Clark, S. and subduction zone of Andean type-The Andes American Earth Sciences 9(5-6): 367-379. Burchfiel, C. (eds.) Processes in Continental of Peru and Bolivia during the Pliocene- Palma, M. and Vujovich, G. 1987, Evidencias Lithospheric Deformation, Geological So- Pleistocene. Journal of Geophysical Research neotectónicas en el borde oriental de la Sierra ciety of America, Special Paper 218: 31-54. 97 (B8): 11,945-11,982. de Calalaste, Puna Catamarqueña. 10° Con- Ramos, V.A. 1989. Foothills structure in Mon, R. 1976. La tectónica del borde oriental de greso Geológico Argentino, Actas 1: 243-249. Northern Magallanes Basin, Argentina. los Andes en las Provincias de Salta, Paris, G. and Sarria, A. 1986. Proyecto geofísico American Association Petroleum Geologists Tucumán y Catamarca, República Argentina. del nordeste Colombiano. Informe INGEO- 73(7): 887-903. Revista de la Asociación Geológica Argentina MINAS-ISA, 59 p., Bogotá. Ramos, V.A. 1999. Plate tectonic setting of the 31: 65-72. Paris, G., and Romero, R. 1994. Fallas Activas en Andean Cordillera. Episodes 22: 183-190. Mon, R. and Gutierrez, A. 2005. The neotecto- Colombia. INGEOMINAS, Boletín Geoló- Ramos, V.A. and Kay, S. 1991. Triassic rifting nic origin of the natural dam of Mar Chi- gico INGEOMINAS 34(2-3): 3-26, Bogotá. and associated basalts in the Cuyo basin, quita, Córdoba, Argentina. ICSU Dark Paris, G., Machette, M., Dart, R., and Haller, K. Central Argentina, in R. Harmon and C. Nature-IGCP 490 Joint Meeting, Abstracts 2000. Map and Database of Quaternary Rapela (eds.), Andean magmatism and its and Field Guide, 33 p. Faults and Folds in Colombia and its offsho- Tectonic Setting. Geological Society of Ame- Moretti, I., Baby, P., Mendez, E., and Zubieta, D. re Regions U.S.Geological Survey Open-File rica, Special Paper 265: 79-91. 1996. Hydrocarbon generation in relation to Report 00-284, 66 p. Ramos, V.A., Cristallini, E.O. and Pérez, D.J. thrusting in the Sub Andean Zone from 18 to Pavlides, S. 1989. Looking for a definition of 2002. The Pampean flat-slab of the Central 22°S - Bolivia. Petroleum Geoscience 2: 17-28. Neotectonics. Terra Nova 1: 233-235. Andes. Journal of South American Earth Mörner, N. 1994. Neotectonics in new perspec- Pennington, W.D. 1981. Subduction of the eas- Sciences 15: 59-78. tives. Bulletin INQUA Neotectonics Com- tern Panama basin and seismotectonics of Ramos, V.A., Alonso, R. and Strecker, M. 2003. mission 18: 63-65. northwestern South America. Journal of Neotectónica cuaternaria en Lomas de Muñoz, N. and Charrier, R. 1996. Uplift of the Geophysical Research 86: 10,753-10,770. Olmedo, provincia de Salta - Argentina. 10° western border of the Altiplano on a west- Pérez, O. and Aggarwal, Y. 1981. Present-day Congreso Geológico Chileno, Actas electró- vergent thrust system, northern Chile. tectonics of southeastern Caribbean and nor- nicas (11 p.). Journal of South American Earth Sciences 9 theastern Venezuela. Journal of Geophysical Ramos, V., Alonso, R. and Strecker, M. 2006. (3/4): 171-181. Research 86:10,791-10,805. Estructura y Neotectónica de las Lomas de Nóbrega, M.A., Sá, J.M., Bezerra, F.H.R., Hadler Pérez, O., Bilham, R., Bendick, R., Hernández, Olmedo, zona de transición entre los siste- Neto, J.C., Lunes, P.J., Oliveira, S.G., Saenz, N., Hoyer, M., Velandia, J., Moncayo, C. and mas Subandino y de Santa Bárbara, provincia C.A.T. and Lima Filho, F.P. 2006. The use of Kozuch, M. 2001. Velocidad relativa entre las de Salta. Revista Asociación Geológica Ar- apatite fission track thermochronology to placas del Caribe y Sudamérica a partir de gentina (this volume). constrain fault movements and sedimentary observaciones dentro del sistema de posicio- Regairaz, A., and Videla Leaniz, J. 1968. basin evolution in northeastern Brazil. namiento global (GPS) en el norte de Fenómenos de la neotectónica y su influencia Radiation Measurements, in press, Amster- Venezuela. Interciencia 26(2): 69-74. sobre la morfología actual del piedemonte dam. Peulvast, J.P., Claudino Sales, V., Bezerra, H., and mendocino. 3° Jornadas Geológicas Argen- Norabuena, E., Leffler, G.L., Mao, A., Dixon, T., Betard, F. 2006. Landforms and neotectonics tinas, Actas 2: 21-34. Stein, S., Sacks, I., and Ellis, M. 1998. Space on a passive margin: the equatorial side of Reutter, K.J., Giese P., Gotze H.J., Scheuber, E., geodetic observations of Nazca-South Ame- northeastern Brazil. Geodinamica Acta, in Schwab, K., Schwarz G., and Wigger, P. 1988. rica convergence across the Central Andes. press. Structures and crustal development of the Science 279(5349): 358-362. Plafker, G.. and Savage, J.C. 1970. Mechanism of Central Andes between 21° and 25° S. In Okada, A. 1971. On the neotectonics of the the Chilean earthquakes of May 21 and 22, Bahlburg, H., Breitkreuz, Ch., and Giese, P. Atacama fault zone region. Preliminary notes 1960: Geological Society of America Bulletin (eds.) The Southern Central Andes. Springer on late Cenozoic faulting and geomorphic 81: 1001-1030. Verlag, Lecture notes in Earth Sciences: 231- developement of Coast Range of northern Polanski, J. 1963. Estratigrafia, neotectónica y 261, Berlin. Chile. Bulletin of the Department of Geo- geomorfología del Pleistoceno pedemontano Riccomini, C. and Assumpção, M. 1999. Qua- graphy, Kyoto University 3: 47-65. entre los Ríos Diamante y Mendoza. Revista ternary tectonics in Brazil. Episodes 22(3): 478 C. H. COSTA, F. A. AUDEMARD M., F. H. R. BEZERRA, A. LAVENU, M. N. MACHETTE AND G. PARÍS

221-225. intervals, and slip rates along the Cordillera (10Be) et quantification de la déformation Riccomini, C., Peloggia, A., Saloni, J., Kohnke, Blanca fault zone, northern Peruvian Andes. active dans les Andes centrales. Ph.D. thesis, M., and Figueira, R. 1989. Neotectonic acti- EOS, Transactions, American Geophysical Université de Paris, Orsay. vity in the Serra do Mar Rift system (SE Union 65(45): 1082. Siame, L., Bourles, D., Sébrier, M., Bellier, O., Brazil). Journal of South American Earth Schwartz, D., Stenner, H., Costa, C., Smalley, R., Castano, J., Araujo, M., Pérez, M., Raisbeck, Sciences 2(2): 191-192. Ellis, M., and Velasco, S. 2001. Paleoseis- G., and Yiou, F. 1997a. Cosmogenic dating Robertson, K. 1989. Actividad neotectónica en mology at the southern end of the world- from 20 to 700ka of a series of alluvial fan el piedemonte de la Cordillera Oriental, sec- Initial observations of the Fagnano fault, Te- surfaces affected by El Tigre fault, Argentina. tor Villavicencio-Tauramena, Colombia. 5° rra del Fuego, Argentina. Seismological Re- Geology 25: 975-978. Congreso Colombiano de Geología, Memo- search Letters 72(2): 265. Siame, L.L., Sébrier, M., Bellier, O., Bourlés, rias 1: 171-192. Schwartz, D., Stenner, H., Costa, C., Smalley, R., D.L., Castano, J. and Araujo, M. 1997b. Rossello, E.A. and Bordarampé, C.P. 2005. Las Ellis, M. y Velasco, S. 2002. Rupturas asocia- Geometry, segmentation and displacement lomadas de Otumpa:Nuevas evidencias car- das a los sismos Ms 7.8 de 1949 en Tierra del rates of the El Tigre fault, San Juan Province tográficas de deformación neotectónica en el Fuego. Investigaciones paleosismológicas ini- (Argentina) from SPOT image analysis and Gran Chaco (Santiago del Estero, Argentina). ciales. 15º Congreso Geológico Argentino, 10Be datings. Annales Tectonicae 1-2: 3-26. 16° Congreso Geológico Argentino, Actas 4: Actas en CD-ROM, Comunicación 149, 3 p. Siame L., Bellier, O., Sébrier, M., Bourlès, D. 479-484. Sébrier, M. and Soler, P. 1991. Tectonics and Leturmy, P., Perez. M. and Araujo, M. 2002. Saadi, A. 1993. Neotectônica da Plataforma magmatism in the Peruvian Andes from Late Seismic hazard reappraisal from combined Brasileira: esboço e interpretação prelimina- Oligocene to the present. In Harmon, R. and structural geology, geomorphology and cos- res. Geonomos 1(1): 1-15. Rapela, C. (eds.) Andean magmatism and its mic ray exposure dating analyses: the Saadi, A., Machette, M.N., Haller, K.M., Dart, tectonic setting, Geological Society of Ame- Eastern Precordillera thrust system (NW R.L., Bradley, L.-A., de Souza, A.M. 2002. rica, Special Paper 265: 259-276. Argentina). Geophysical Journal Internatio- Map and Database of Quaternary Faults and Sébrier, M., Huamán, J., Blanc, J-L., Macharé, J., nal 150: 241-260. Lineaments in Brazil: U.S. Geological Survey Bonnot, D. and Cabrera, J. 1982. Obser- Siame, L., Bellier, O., Sébrier, M. and Araujo, M. Open-File Report 02-230, 58 p. vaciones acerca de la Neotectónica del Perú. 2005. Deformation partitioning in flat sub- Saadi, A., Bezerra, F.H.R., Costa, R.D., Igreja, Informe Proyecto SISRA, 110 p., Lima. duction setting: Case of the Andean foreland H.L.S., and Franzinelli, E. 2005. Neotectôni- Sébrier, M., Mercier, J.L., Mégard, F., Laubacher, of western Argentina (28°S-33°S). Tectonics ca na Plataforma Brasileira. In Souza, C.R.G., G., and Carey-Gailhardis, E. 1985. Quater- 24, TC5003, doi:10.1029/2005TC001787. Suguio, K., Oliveira, A.M.S., Oliveira, P.E. nary normal and reverse faulting and the Singer, A. and Audemard, F.A. 1997. Aportes de (eds.) Quaternário do Brasil, Holos Editora. state of stress in central Andes of Southern Funvisis al desarrollo de la geología de fallas Sagripanti, G.L., Costa, C.H., Giaccardi, A.D., Peru. Tectonics 4(7): 739-780. activas y de la paleosismología para los estu- Aguilera, D., Schiavo, H.F., Campanella, O.R., Sébrier, M., Lavenu, A., Fornari, M. and Soulas, dios de amenaza y riesgo sísmico. Publicación and Dolso, A.C. 1999. Nuevos datos sobre la J. 1988. Tectonics and uplift in Central Andes Especial Academia de las Ciencias Naturales, actividad cuaternaria de la Falla Las Lagunas, (Perú, Bolivia and Northern Chile) from Matemáticas y Físicas 33: 25-38. Departamento de Río Cuarto, Córdoba. 14° Eocene to present. Geodynamique 3: 85-106. Silgado, E. 1951. The Ancash, Peru, earthquake Congreso Geológico Argentino, Actas 1: 42- Schubert, C. 1979. El Pilar fault zone, northeas- of November 10, 1946. Bulletin of the 43, Salta. tern Venezuela: brief review. Tectonophysics Seismological Society of America 41: 83-100. Saint Amand, P. 1963. Oceanographic, geologic, 52: 447-455. Smalley, R. Jr., Pujol, J., Regnier, M., Chiu, J.M., and engineering studies of the Chilean earth- Schubert, C. 1980a. Morfología neotectónica de Chatelain, J.L., Isacks, B.L., Araujo, M. and quakes of May 1960. Bulletin of the una falla rumbo-deslizante e informe prelimi- Puebla, N. 1993. Basement seismicity bene- Seismological Society of America 53(6): nar sobre la falla de Boconó, Andes meride- ath the Andean Precordillera thin-skinned 1123-1436. ños. Acta Científica Venezolana 31: 98-111. thrust belt and implications for crustal and Saint Amand, P. and Allen, C. 1960. Strike-slip Schubert, C. 1980b. Late Cenozoic pull-apart lithospheric behavior. Tectonics 12: 63-76. faulting in northern Chile (abst.). Bulletin of basins, Boconó fault zone, Venezuelan Smalley, R., Jr., Kendrick, E., Bevis, M., Dalziel, the Geological Society of America 71: 19-65. Andes. Journal of Structural Geology 2(4): I., Taylor, F., Lauría, E., Barriga, R., Casassa, Sarria, A. 1990. Ingenieria Sismica. Universidad 463-468. G., Olivero, E. and Piana, F. 2003. Geodetic de los Andes, 610 p., Bogotá. Schubert, C. 1982. Neotectonics of the Boconó determination of relative plate motion and Schwartz, D. 1988. Paleoseismicity and neotecto- fault, western Venezuela. Tectonophysics 85: crustal deformation across the Scotia-South nics of the Cordillera Blanca fault zone, 205-220. America plate boundary in eastern Tierra del Northern Peruvian Andes. Journal of Schubert, C. 1984. Basin formation along Fuego. Geochemistry Geophysics Geosys- Geophysical Research 93: 4712-4730. Boconó-Morón-El Pilar fault system, tems 4(9): 1070, doi:10.1029/2002GC000 Schwartz, D.P., Salazar, H., Felix, O., Santucci, Venezuela. Journal of Geophysical Research 446. H., Arnt, A., La Cruz, J., and Farfan, M. 1984. 89: 5711-5718. Soulas, J.P. 1978. Tectonique cuaternaire: la côte Late Quaternary normal faulting, recurrence Siame, L. 1998. Cosmonucléide produit in-situ pacifique et la chaine andine du Pérou An overview of the main quaternary deformation of South America 479

Central. Revue Geographie Physique et Géo- J., and Rivera, C. 2000. Geodinamics in nor- terremoto de Caucete del 23 de noviembre de logie Dynámique 20(5): 399-414. thern Andes: Subductions and intracontinen- 1977. Publicación Instituto Sismológico Soulas, J-P. 1986. Neotectónica y tectónica activa tal deformations (Colombia). Tectonics 19: Zonda, 81 p. San Juan. en Venezuela y regiones vecinas. 6º Congreso 787-813. Weber J., Dixon, T., DeMets, C., Ambeh, W., Geológico Venezolano, Proceedings 10: Takeya, M., Ferreira, J.M., Pearce, R.G., Jansma, P., Mattioli, G., Saleh, J., Sella, G., 6639-6656. Assumpção, M., Costa, J.M. and Sophia, C.M. Bilham, R. and Pérez, O. 2001. GPS estimate Soulas, J.P., Egüez, A., Yepes, H., and Pérez, V.H. 1989. The 1986-1988 intraplate earthquake of relative motion between the Caribbean 1991, Tectónica activa y riesgo sísmico en sequence near João Câmara, NE Brazil- and South American plates, and geologic Los Andes Ecuatorianos y el extremo sur de Evolution of seismicity. Tectonophysics 167: implications for Trinidad and Venezuela. Colombia. Boletín de Geologia Ecuatoriano 117-131. Geology 29 (1): 75-78. 2(1): 3-11. Tello, G. 1994. Fallamiento Cuaternario y sismi- Winslow, M. 1982. The structural evolution of Stein, R., and Yeats, R. 1989. Hidden earthqua- cidad en el piedemonte Cordillerano de la the Magallanes Basin and Neotectonics of kes. Scientific American 260: 48-57. Provincia de Mendoza, Argentina. 7° Con- the Southernmost Andes. In Craddock, C. Stephan, J-F. 1982. Evolution géodinamique du greso Geológico Chileno, Actas 1: 380-384. (ed.) Antarctic Geoscience, University of domaine Caraïbe, Andes et chaine Caraibe Triep, E. 1987. La falla activada durante el sismo Wisconsin: 143-154. sur la transversale de Barquisimeto (Vene- principal de Mendoza de 1985 e implicancias Winslow, M. and Prieto, X. 1991. Evidence of zuéla). PhD Thesis,Université de Paris, 512 tectónicas. 10º Congreso Geológico Argen- active tectonics along the strait of Magellan, p., Paris. tino, Actas 1: 199-202. Chile. 6° Congreso Geológico Chileno, Resú- Suárez, G., Molnar, P., and Burchfield, C. 1983. Trifonov, V.G., and Machette, M.N. 1993. The menes Expandidos: 654-655. Seismicity, fault plane solutions, depth of World Map of Major Active faults Project, Zapata, T., and Allmendinger, R. 1996. Thrust faulting and active tectonics of the Andes of Annali di Geofisica 36(3-4): 225-236. front zone of the Precordillera, Argentina-A Perú, Ecuador and Southern Colombia. Velandia, F., Acosta, J., Terraza, R. and Villegas, thick-skinned triangle zone. American Asso- Journal of Geophysical Research 89: 10,403- H. 2005. The current tectonic motion of the ciation of Petroleum Geologists, Bulletin 80: 10,428. Northern Andes along the Algeciras fault in 359-381. Sykes, L., McCann, W.R., and Kafka, A.L. 1978. SW Colombia. Tectonophysics 399: 313-329. Zeil, W. 1979. The Andes; a geological review. Motion of the Caribbean plate during last 7 Vita-Finzi, C. 1987. Recent earth movements. Beitraege zúr Regionalen Geologie der Erde millon years and implications for earlier Academic Press, 226 p. 13, 260 p., Berlin. Cenozoic movements. Journal of Geophy- Vita-Finzi, C. 1996. Paleoseismology in coastal sical Research 87: 10656-10676. Chile. Journal of Geophysical Research Taboada, A., Rivera, L. A., Fuenzalida, A., 101(B3): 6109-6114. Recibido: 30 de junio , 2006 Cisternas, A., Philip, H., Bijwaard, H., Olaya, Volponi, F., Quiroga, M. and Robles, A. 1978. El Aceptado: 15 de noviembre, 2006