Stress Modeling of the Nazca Plate: Advances in Modeling Ridge-Push and Slab-Pull Forces
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Kinematic Reconstruction of the Caribbean Region Since the Early Jurassic
Earth-Science Reviews 138 (2014) 102–136 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev Kinematic reconstruction of the Caribbean region since the Early Jurassic Lydian M. Boschman a,⁎, Douwe J.J. van Hinsbergen a, Trond H. Torsvik b,c,d, Wim Spakman a,b, James L. Pindell e,f a Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands b Center for Earth Evolution and Dynamics (CEED), University of Oslo, Sem Sælands vei 24, NO-0316 Oslo, Norway c Center for Geodynamics, Geological Survey of Norway (NGU), Leiv Eirikssons vei 39, 7491 Trondheim, Norway d School of Geosciences, University of the Witwatersrand, WITS 2050 Johannesburg, South Africa e Tectonic Analysis Ltd., Chestnut House, Duncton, West Sussex, GU28 OLH, England, UK f School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff CF10 3YE, UK article info abstract Article history: The Caribbean oceanic crust was formed west of the North and South American continents, probably from Late Received 4 December 2013 Jurassic through Early Cretaceous time. Its subsequent evolution has resulted from a complex tectonic history Accepted 9 August 2014 governed by the interplay of the North American, South American and (Paleo-)Pacific plates. During its entire Available online 23 August 2014 tectonic evolution, the Caribbean plate was largely surrounded by subduction and transform boundaries, and the oceanic crust has been overlain by the Caribbean Large Igneous Province (CLIP) since ~90 Ma. The consequent Keywords: absence of passive margins and measurable marine magnetic anomalies hampers a quantitative integration into GPlates Apparent Polar Wander Path the global circuit of plate motions. -
Shape of the Subducted Rivera and Cocos Plates in Southern Mexico
JOURNALOF GEOPHYSICAL RESEARCH, VOL. 100, NO. B7, PAGES 12,357-12,373, JULY 10, 1995 Shapeof the subductedRivera and Cocosplates in southern Mexico: Seismic and tectonicimplications Mario Pardo and Germdo Sufirez Insfitutode Geoffsica,Universidad Nacional Aut6noma de M6xico Abstract.The geometry of thesubducted Rivera and Cocos plates beneath the North American platein southernMexico was determined based on the accurately located hypocenters oflocal and te!eseismicearthquakes. The hypocenters ofthe teleseisms were relocated, and the focal depths of 21 eventswere constrainedusing a bodywave inversion scheme. The suductionin southern Mexicomay be approximated asa subhorizontalslabbounded atthe edges by the steep subduction geometryof theCocos plate beneath the Caribbean plate to the east and of theRivera plate beneath NorthAmerica to thewest. The dip of theinterplate contact geometry is constantto a depthof 30 kin,and lateral changes in thedip of thesubducted plate are only observed once it isdecoupled fromthe overriding plate. On thebasis of theseismicity, the focal mechanisms, and the geometry ofthe downgoing slab, southern Mexico may be segmented into four regions ß(1) theJalisco regionto thewest, where the Rivera plate subducts at a steepangle that resembles the geometry of theCocos plate beneath the Caribbean plate in CentralAmerica; (2) theMichoacan region, where thedip angleof theCocos plate decreases gradually toward the southeast, (3) theGuerrero-Oaxac.a region,bounded approximately by theonshore projection of theOrozco and O'Gorman -
Interplate Coupling Along the Nazca Subduction Zone on the Pacific Coast of Colombia Deduced from Geored GPS Observation Data
Volume 4 Quaternary Chapter 15 Neogene https://doi.org/10.32685/pub.esp.38.2019.15 Interplate Coupling along the Nazca Subduction Published online 28 May 2020 Zone on the Pacific Coast of Colombia Deduced from GeoRED GPS Observation Data Paleogene Takeshi SAGIYA1 and Héctor MORA–PÁEZ2* 1 [email protected] Nagoya University Disaster Mitigation Research Center Nagoya, Japan Abstract The Nazca Plate subducts beneath Colombia and Ecuador along the Pacific Cretaceous coast where large megathrust events repeatedly occur. Distribution of interplate 2 [email protected] Servicio Geológico Colombiano coupling on the subducting plate interface based on precise geodetic data is im- Dirección de Geoamenazas portant to evaluate future seismic potential of the megathrust. We analyze recent Space Geodesy Research Group Diagonal 53 n.° 34–53 continuous GPS data in Colombia and Ecuador to estimate interplate coupling in the Bogotá, Colombia Jurassic Nazca subduction zone. To calculate the interplate coupling ratio, in addition to the * Corresponding author MORVEL plate velocities, three different Euler poles for the North Andean Block are tested but just two of them yielded similar results and are considered appropriate for discussing the Pacific coastal area. The estimated coupling distribution shows four main locked patches. The middle two locked patches correspond to recent large Triassic earthquakes in this area in 1942, 1958, and 2016. The southernmost locked patch may be related to slow slip events. The northern locked patch has a smaller coupling ra- tio of less than 0.5, which may be related to the large earthquake in 1979. However, because of the sparsity of the GPS network, detailed interpretation is not possible. -
Back-Arc Opening and the Mode of Subduction
VOL.84, NO. B3 JOURNALOF GEOPHYSICALRESEARCH MARCH10, 1979 Back-ArcOpening and the Mode of Subduction SEIYA UYEDA EarthquakeResearch Institute, University of Tokyo,Tokyo, Japan HIROO K ANAMORI SeismologicalLaboratory, California Institute of Technology,Pasadena, California 91125 Trench-arcsystems (subduction zones) can be classified into two types depending onwhether or not activelyopening back-arc basins are associated with them. This suggests that subduction of an oceanic plateis not a sufficientcondition for back-arc opening, though it may be necessary one. Mechanisms that causethe distinction between the two types have been investigated. Earthquake studies suggest that there isa significantdifference inthe mode of plate motion at interplate boundaries between the two types of trench-arcsystems. Extreme cases are Chile, where plate motion is seismic, and the M arianas arc, where it is aseismic.This difference seems to indicatethat the stress state in theback-arc area differs between the twotypes: compression in the Chilean type and tension in theMarianas type. This difference in thestress stateis alsomanifested in other tectonic features, such as topography, gravity, volcanic activity, and crustalmovement. Two possible mechanisms forthe difference between the two types are suggested: (1) Thenature of thecontact zone between upper and lower plates chahges from tight coupling (Chile) to decoupling(the Marianas) through the evolutionary process ofsubduction. The decoupling results inan oceanwardretreat of the trench and back-arc opening. (2) The downgoing slab is anchored tothe mantle, sothat the position of a trenchis also fixed with respect to themantle. Since the motion in themantle is slowcompared tothat of surface plates, it is the motion of the landward plate which controls the opening and nonopeningof back-arcs. -
Chapter 4 Tectonic Reconstructions of the Southernmost Andes and the Scotia Sea During the Opening of the Drake Passage
123 Chapter 4 Tectonic reconstructions of the Southernmost Andes and the Scotia Sea during the opening of the Drake Passage Graeme Eagles Alfred Wegener Institute, Helmholtz Centre for Marine and Polar Research, Bre- merhaven, Germany e-mail: [email protected] Abstract Study of the tectonic development of the Scotia Sea region started with basic lithological and structural studies of outcrop geology in Tierra del Fuego and the Antarctic Peninsula. To 19th and early 20th cen- tury geologists, the results of these studies suggested the presence of a submerged orocline running around the margins of the Scotia Sea. Subse- quent increases in detailed knowledge about the fragmentary outcrop ge- ology from islands distributed around the margins of the Scotia Sea, and later their interpretation in light of the plate tectonic paradigm, led to large modifications in the hypothesis such that by the present day the concept of oroclinal bending in the region persists only in vestigial form. Of the early comparative lithostratigraphic work in the region, only the likenesses be- tween Jurassic—Cretaceous basin floor and fill sequences in South Geor- gia and Tierra del Fuego are regarded as strong enough to be useful in plate kinematic reconstruction by permitting the interpretation of those re- gions’ contiguity in mid-Mesozoic times. Marine and satellite geophysical data sets reveal features of the remaining, submerged, 98% of the Scotia 124 Sea region between the outcrops. These data enable a more detailed and quantitative approach to the region’s plate kinematics. In contrast to long- used interpretations of the outcrop geology, these data do not prescribe the proximity of South Georgia to Tierra del Fuego in any past period. -
Large Intermediate-Depth Earthquakes and the Subduction Process
80 Physics ofthe Earth and Planetary Interiors, 53 (1988) 80—166 Elsevier Science Publishers By., Amsterdam — Printed in The Netherlands Large intermediate-depth earthquakes and the subduction process Luciana Astiz ~, Thorne Lay 2 and Hiroo Kanamori ~ ‘Seismological Laboratory, California Institute of Technology, Pasadena, CA (U.S.A.) 2 Department of Geological Sciences, University ofMichigan, Ann Arbor, MI (USA.) (Received September 22, 1987; accepted October 21, 1987) Astiz, L., Lay, T. and Kanamori, H., 1988. Large intermediate-depth earthquakes and the subduction process. Phys. Earth Planet. Inter., 53: 80—166. This study provides an overview of intermediate-depth earthquake phenomena, placing emphasis on the larger, tectonically significant events, and exploring the relation of intermediate-depth earthquakes to shallower seismicity. Especially, we examine whether intermediate-depth events reflect the state of interplate coupling at subduction zones. and whether this activity exhibits temporal changes associated with the occurrence of large underthrusting earthquakes. Historic record of large intraplate earthquakes (m B 7.0) in this century shows that the New Hebrides and Tonga subduction zones have the largest number of large intraplate events. Regions associated with bends in the subducted lithosphere also have many large events (e.g. Altiplano and New Ireland). We compiled a catalog of focal mechanisms for events that occurred between 1960 and 1984 with M> 6 and depth between 40 and 200 km. The final catalog includes 335 events with 47 new focal mechanisms, and is probably complete for earthquakes with mB 6.5. For events with M 6.5, nearly 48% of the events had no aftershocks and only 15% of the events had more than five aftershocks within one week of the mainshock. -
How Does the Nazca Ridge Subduction Influence the Modern Amazonian Foreland Basin?
Downloaded from geology.gsapubs.org on November 26, 2015 How does the Nazca Ridge subduction infl uence the modern Amazonian foreland basin? N. Espurt* LMTG, Université de Toulouse, CNRS, IRD, OMP, 14 Avenue Edouard Belin, F-31400 Toulouse, France, and P. Baby* IRD, Convenio IRD-PERUPETRO, Calle Teruel 357, Mirafl ores, Lima 18, Peru S. Brusset* LMTG, Université de Toulouse, CNRS, IRD, OMP, 14 Avenue Edouard Belin, F-31400 Toulouse, France M. Roddaz* W. Hermoza* PERUPETRO, Convenio IRD-PERUPETRO, Avenida Luis Aldana 320, San Boja, Lima 41, Peru V. Regard* LMTG, Université de Toulouse, CNRS, IRD, OMP, 14 Avenue Edouard Belin, F-31400 Toulouse, France P.-O. Antoine* R. Salas-Gismondi* Museo de Historia Natural—UNMSM, Departamento de Paleontología de Vertebrados, Avenida Arenales 1256, Lima 14, Peru R. Bolaños* PERUPETRO, Convenio IRD-PERUPETRO, Avenida Luis Aldana 320, San Boja, Lima 41, Peru ABSTRACT Fitzcarrald arch is incised by these rivers, and the The subduction of an aseismic ridge has important consequences on the dynamics of the oldest outcropping sediments are Neogene in age. overriding upper plate. In the central Andes, the Nazca Ridge subduction imprint can be Recent studies of both sides of the arch (Fig. 2A) tracked on the eastern side of the Andes. The Fitzcarrald arch is the long-wavelength topog- show Late Miocene tidal deposits (Räsänen et al., raphy response of the Nazca Ridge fl at subduction, 750 km inboard of the trench. This uplift 1995; Hovikoski et al., 2005; Gingras et al., 2002; is responsible for the atypical three-dimensional shape of the Amazonian foreland basin. -
19. Analysis and Correlation of Volcanic
Jørgensen, B.B., D’Hondt, S.L., and Miller, D.J. (Eds.) Proceedings of the Ocean Drilling Program, Scientific Results Volume 201 19. ANALYSIS AND CORRELATION OF VOLCANIC ASH IN MARINE SEDIMENTS FROM THE PERU MARGIN, OCEAN DRILLING PROGRAM LEG 201: EXPLOSIVE VOLCANIC 1 CYCLES OF THE NORTH-CENTRAL ANDES D. Hart2 and D.J. Miller3 ABSTRACT Although land studies have identified major volcanic centers of his- 1Hart, D., and Miller, D.J., 2006. toric eruptions within the Central Andes, the tephrachronologic record Analysis and correlation of volcanic is disturbed by the high erosion rates in this arid region. Owing to ero- ash in marine sediments from the Peru sion, studies of volcanic cyclicity based on subaerial deposits offer an margin, Ocean Drilling Program Leg incomplete record of the frequency and episodicity of eruptions since 201: explosive volcanic cycles of the north-central Andes. In Jørgensen, the Miocene. However, volcanic material commonly occurs in marine B.B., D’Hondt, S.L., and Miller, D.J. sediment as discrete ash fall layers and/or disseminated ash accumula- (Eds.), Proc. ODP, Sci. Results, 201, 1–43 tions. A detailed investigation of cores from three sites offshore Peru [Online]. Available from World Wide drilled during Ocean Drilling Program (ODP) Leg 201 has been con- Web: <http://www-odp.tamu.edu/ ducted to determine the occurrence of volcanic ash layers and ash accu- publications/201_SR/VOLUME/ CHAPTERS/122.PDF>. [Cited YYYY- mulations within marine sediments along the Peru shelf. These sites MM-DD] were previously occupied during ODP Leg 112, which suffered from 2Department of Geology and poor and/or disturbed core recovery. -
Measurements of Upper Mantle Shear Wave Anisotropy from a Permanent Network in Southern Mexico
GEOFÍSICA INTERNACIONAL (2013) 52-4: 385-402 ORIGINAL PAPER Measurements of upper mantle shear wave anisotropy from a permanent network in southern Mexico Steven A. C. van Benthem, Raúl W. Valenzuela* and Gustavo J. Ponce Received: November 13, 2012; accepted: December 14, 2012; published on line: September 30, 2013 Resumen Abstract Se midió la anisotropía para las ondas de cortante 8SSHU PDQWOH VKHDU ZDYH DQLVRWURS\ XQGHU en el manto superior por debajo de estaciones VWDWLRQVLQVRXWKHUQ0H[LFRZDVPHDVXUHGXVLQJ en el sur de México usando fases SKS. Las records of SKS phases. Fast polarization directions direcciones de polarización rápida donde la placa ZKHUHWKH&RFRVSODWHVXEGXFWVVXEKRUL]RQWDOO\ de Cocos se subduce subhorizontalmente están are oriented in the direction of the relative orientadas aproximadamente paralelas con el PRWLRQEHWZHHQWKH&RFRVDQG1RUWK$PHULFDQ movimiento relativo entre las placas de Cocos y plates, and are trench-perpendicular. This América del Norte y además son perpendiculares SDWWHUQLVLQWHUSUHWHGDVVXEVODEHQWUDLQHGÀRZ DODWULQFKHUD3RUORWDQWRVHLQ¿HUHTXHODSODFD and is similar to that observed at the Cascadia VXEGXFLGD DUUDVWUD HO PDQWR TXH VH HQFXHQWUD subduction zone. Earlier studies have pointed SRUGHEDMR\ORKDFHÀXLU HQWUDLQHGÀRZ 8QD out that both regions have in common the young situación similar existe en la zona de subducción age of the subducting lithosphere. Changes in the GH&DVFDGLD(VWXGLRVSUHYLRVKDQVHxDODGRTXH RULHQWDWLRQRIWKHIDVWD[HVDUHREVHUYHGZKHUH estas dos regiones tienen en común la subducción the subducting -
Structure of the Collision Zone Between the Nazca Ridge and the Peruvian Convergent Margin
RESEARCH ARTICLE Structure of the Collision Zone Between the Nazca Ridge 10.1029/2019TC005637 and the Peruvian Convergent Margin: Geodynamic Key Points: • The Nazca Ridge hosts an and Seismotectonic Implications overthickened lower crust E. Contreras‐Reyes1 , P. Muñoz‐Linford2, V. Cortés‐Rivas1, J. P. Bello‐González3, J. A. Ruiz1, (10–14 km) formed in an on‐ridge 4 setting (hot spot plume near a and A. Krabbenhoeft spreading center) 1 2 • The Nazca Ridge correlates with a Departamento de Geofísica, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile, Centro prominent continental slope scarp I‐MAR, Universidad de los Lagos, Puerto Montt, Chile, 3Grupo Minero Las Cenizas, Taltal, Chile, 4GEOMAR‐Helmholtz bounded by a narrow and uplifted Centre for Ocean Research, Kiel, Germany continental shelf • The Nazca Ridge has behaved as a seismic asperity for moderate earthquakes (e.g., 1996 Mw 7.7 and Abstract We study the structure and tectonics of the collision zone between the Nazca Ridge (NR) and 2011 Mw 6.9) nucleating at depths the Peruvian margin constrained by seismic, gravimetric, bathymetric, and natural seismological data. >20 km The NR was formed in an on‐ridge setting, and it is characterized by a smooth and broad shallow seafloor (swell) with an estimated buoyancy flux of ~7 Mg/s. The seismic results show that the NR hosts an Supporting Information: – – • Supporting Information S1 oceanic lower crust 10 14 km thick with velocities of 7.2 7.5 km/s suggesting intrusion of magmatic material from the hot spot plume to the oceanic plate. Our results show evidence for subduction erosion in the frontal part of the margin likely enhanced by the collision of the NR. -
Map and Database of Quaternary Faults in Venezuela and Its Offshore Regions
U.S. Department of the Interior U.S. Geological Survey Map and Database of Quaternary Faults in Venezuela and its Offshore Regions By Franck A. Audemard M., Michael N. Machette, Jonathan W. Cox, Richard L. Dart, and Kathleen M. Haller Open-File Report 00-018 (paper edition) This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards nor with the North American Stratigraphic Code. Any use of trade names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey. 2000 Map and Database of Quaternary Faults in Venezuela and its Offshore Regions A project of the International Lithosphere Program Task Group II-2, Major Active Faults of the World Data and map compiled by 1 FRANCK A. AUDEMARD M., 2 MICHAEL N. MACHETTE, 2 JONATHAN W. COX, 2 RICHARD L. DART, AND 2 KATHLEEN M. HALLER 1 Fundación Venezolana de Investigaciones Sismológicas (FUNVISIS) Dpto. Ciencias de la Tierra, Prolongacion Calle Mara, El Llanito Caracas 1070-A, Venezuela 2 U.S. Geological Survey (USGS) Central Geologic Hazards Team MS 966, P.O. Box 25046 Denver, Colorado, USA Regional Coordinator for Central America CARLOS COSTA Universidad Nacional de San Luis Departmento de Geologia Casilla de Correo 320 San Luis, Argentina ILP Task Group II-2 Co-Chairman, Western Hemisphere MICHAEL MACHETTE U.S. Geological Survey (USGS) Central Geologic Hazards Team MS 966, P.O. Box 25046 Denver, Colorado, USA January 2000 version i TABLE OF CONTENTS PAGE INTRODUCTION...............................................................................................................................................................1 -
Geometry and Seismic Properties of the Subducting Cocos Plate in Central Mexico Y
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115, B06310, doi:10.1029/2009JB006942, 2010 Click Here for Full Article Geometry and seismic properties of the subducting Cocos plate in central Mexico Y. Kim,1 R. W. Clayton,1 and J. M. Jackson1 Received 31 August 2009; revised 22 December 2009; accepted 25 January 2010; published 17 June 2010. [1] The geometry and properties of the interface of the Cocos plate beneath central Mexico are determined from the receiver functions (RFs) utilizing data from the Meso America Subduction Experiment (MASE). The RF image shows that the subducting oceanic crust is shallowly dipping to the north at 15° for 80 km from Acapulco and then horizontally underplates the continental crust for approximately 200 km to the Trans‐ Mexican Volcanic Belt (TMVB). The crustal image also shows that there is no continental root associated with the TMVB. The migrated image of the RFs shows that the slab is steeply dipping into the mantle at about 75° beneath the TMVB. Both the continental and oceanic Moho are clearly seen in both images, and modeling of the RF conversion amplitudes and timings of the underplated features reveals a thin low‐velocity zone between the plate and the continental crust that appears to absorb nearly all of the strain between the upper plate and the slab. By inverting RF amplitudes of the converted phases and their time separations, we produce detailed maps of the seismic properties of the upper and lower oceanic crust of the subducting Cocos plate and its thickness. High Poisson’s and Vp/Vs ratios due to anomalously low S wave velocity at the upper oceanic crust in the flat slab region may indicate the presence of water and hydrous minerals or high pore pressure.