TAILIEUCHUNG - Pre-Cenozoic tectonic deformation phases in the Muong Xen area, Nghe An province

In this research, pre-Cenozoic deformation characteristics will be presented for the Ca River fault zone based on field observations and geological mapping conducted in the Muong Xen area, Nghe An, northwest of the Ca River fault zone. | Vietnam Journal of Earth Sciences, 38(2), 166-177, DOI: Vietnam Academy of Science and Technology (VAST) Vietnam Journal of Earth Sciences Pre-Cenozoic tectonic deformation Muong Xen area, Nghe An province phases in the Nguyen Ba Minh*1, Nguyen Van Vuong2 1 2 General Department of Geology and Minerals of Vietnam University of Science, Vietnam National University, Hanoi Received 6 April 2016. Accepted 23 May 2016 ABSTRACT The Ca River fault zone, located in the North-Central Vietnam, is one of the most complicated deformation zones with very low grade metamorphism but high intense folding. Investigations of deformation conducted in the Muong Xen area, northwest of the Ca River fault zone, show that, the Ca River fault zone had undergone at least three deformation phases before the Cenozoics. The first (oldest) deformation phase is characterized by recumbent, reverse folds and overthrust faults in NW-SE direction. The second deformation phase is characterized by large scale Zshaped folds that deformed oder structures. Those structures are covered by a pre-Late Triassic angular unconformity. The third deformation phase refolds previously formed structures and shows similar characteristics of folding as the first phase. These structures were subsequently deformed by Cenozoic tectonics. Keywords: Ca River fault zone; Pre-Cenozoic defomation; Recumbent folds; Z-shaped folds; Pre-Late Triassic angular unconformity. ©2016 Vietnam Academy of Science and Technology 1. Introduction The Ca River fault zone is located in Nghe An, Ha Tinh provinces, and partly in northern Quang Binh province. Geologically, the fault zone is limited by route 48 faults in the north and Rao Nay fault to the south. Up to date, a number of studies on structural tectonics in this area have been conducted (Nguyen, 1987; Phan, 1995; Bui et al., 1996; 2001; 2002; 2005; 2008; Lepvrier et al., 1997; 2003; 2008; Cao et al., 1998; .

• Địa Lý
• Vietnam Journal of Earth Sciences
• Pre Cenozoic tectonic deformation phases
• The Muong Xen area
• Nghe An province
• The Ca River fault zone
• Z shaped folds
• Pre Late Triassic angular unconformity
• General characteristics of rare earth
• Radioactive elements in Dong Pao deposit
• The natural tap and thermal waters
• Liquid scintillation counter
• Probabilistic seismic hazard assessment for the South Central Vietnam
• Probabilistic seismic hazard assessment
• The South Central Vietnam
• Recent seismotectonic and geodynamic
• Prediction of maximum earthquake magnitude for northern Vietnam region
• The gev distribution
• Maximum earthquake magnitude
• Generalized extreme value distribution
• The earthquake catalog of Northern Vietnam
• Continuous GPS network in Vietnam
• The total electron
• The South East Asian region
• The continuous GPS network
• The South East Asian equatorial ionization anomaly
• Upper Permian lower Triassic volcanic sequences
• The Hoa Binh area
• northwest Vietnam
• Insignificant cumulative displacement
• Oriented core samples
• An analysis of forest biomass changes
• Geospatial tools and ground survey data
• Yok Don national park
• Central Highlands of Vietnam
• SPOT HRV satellite
• The autumn precipitation
• Tropical cyclone activity
• Central Vietnam and its East Sea
• Sea surface temperature
• Adaptation plans anticipated
• Construction of initial national quasi geoid model VIGAC2017
• First step to national spatial reference system in Vietnam
• Coordinate transformation parameters
• The WGS 84 ellipsoid
• Abnormal features of oceanographic characteristics
• Upwelling Vietnam waters under impact of El Niño events
• Deeper water layers during
• El Niño phase
• The relation between fault movement potential
• Seismic activity of major faults in Northwestern Vietnam
• Fault Movement Potential
• The nearly horizontal trend
• U Pb detrital zircon geochronology
• Sedimentary rocks in NE Vietnam
• Implication for Early and Middle Devoni an Palaeogeography
• LA SF ICP MS techniques
• The western Himalaya
• Preliminary study on phytogeography
• Dipterocarpaceae Blume family in Vietnam
• Dipterocarpaceae Blume family
• Tropical and or slightly passing
• The Mekong River deltas
• Impacts of climate change on erosion and water flow
• The soil and water assessment tool and gis
• Cau river basin in Vietnam
• oil and Water Assessment Tool
• Errors in determination of main parameters of earthquake hypocenter
• The national seismic network of Vietnam
• Main parameters of earthquake hypocenter
• The seismic stations
• The previous studies
• Sea level rise and resilience in Vietnam
• Sea level rise and resilience in the AsiaPacific
• Sea level rise and resilience
• Climate change induced sea level rise
• Spatial distribution of hot days in north central region
• Vietnam in the period of 1980 2013
• Hot days in north central region
• North Center Region
• Debris flow hazard in relation
• Geological environment changes in mountainous regions
• Geological environment changes
• Debris flows in Vietnam
• High arsenic concentration in groundwater related to sedimentary facies
• The Mekong River Delta
• High arsenic concentration
• AOAC laboratory Vietnamese standard
• Assessment of geomorphic processes and active tectonics
• Con Voi mountain range area
• The hypsometric curve analysis method
• The hypsometric curve
• Uptake capacity of metals by Vetiveria zizanioides
• Uptake capacity of metals
• Dong Xam metal production trade village
• Thai Binh province
• Metal production trade village
• Coralline Ba Ca ratios
• Luminescent line records
• Con Dao island
• Mekong river runoff
• Bright luminescent lines
• Simulation of long term variations
• The F2 layercritical frequency f0F2
• The northern tropical crest of ionization at Phu Thuy
• The thermosphere ionosphere electrodynamicsgeneral circulation model
• Long term variations
• Methodology of determining effective porosity
• Longitudinal dispersivity of aquifer
• The application to field tracer injection test in Southern Hanoi
• The groundwater flow
• New discovery of late early ordovician graptolites
• Discussion on stratigraphic sequence of paleozoic sediments
• The Dinh Ca Trang Xa section
• Vo Nhai disctrict
• A digital shoreline analysis system
• Mangrove shoreline changes along
• The Giao Thuy coastal area
• Mangrove shoreline changes and mangrove zoning