Mantle Tectonics Beneath New Zealand Inferred from SKS Splitting and Petrophysics
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Using Campaign GPS Data to Model Slip Rates on the Alpine Fault
New Zealand Journal of Geology and Geophysics ISSN: 0028-8306 (Print) 1175-8791 (Online) Journal homepage: http://www.tandfonline.com/loi/tnzg20 A geodetic study of the Alpine Fault through South Westland: using campaign GPS data to model slip rates on the Alpine Fault Chris J. Page, Paul H. Denys & Chris F. Pearson To cite this article: Chris J. Page, Paul H. Denys & Chris F. Pearson (2018): A geodetic study of the Alpine Fault through South Westland: using campaign GPS data to model slip rates on the Alpine Fault, New Zealand Journal of Geology and Geophysics, DOI: 10.1080/00288306.2018.1494006 To link to this article: https://doi.org/10.1080/00288306.2018.1494006 View supplementary material Published online: 09 Aug 2018. Submit your article to this journal View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=tnzg20 NEW ZEALAND JOURNAL OF GEOLOGY AND GEOPHYSICS https://doi.org/10.1080/00288306.2018.1494006 RESEARCH ARTICLE A geodetic study of the Alpine Fault through South Westland: using campaign GPS data to model slip rates on the Alpine Fault Chris J. Page, Paul H. Denys and Chris F. Pearson School of Surveying, University of Otago, Dunedin, New Zealand ABSTRACT ARTICLE HISTORY Although the Alpine Fault has been studied extensively, there have been few geodetic studies Received 11 December 2017 in South Westland. We include a series of new geodetic measurements from sites across the Accepted 25 June 2018 Haast Pass and preliminary results from a recently established network, the Cascade array KEYWORDS that extends from the Arawhata River to Lake McKerrow, a region that previously had few Alpine Fault; slip rates; South geodetic measurements. -
Tectonic Setting Seismic Hazard Epicentral Region
U.S. DEPARTMENT OF THE INTERIOR EARTHQUAKE SUMMARY MAP U.S. GEOLOGICAL SURVEY Prepared in cooperation with the M8.0 Samoa Islands Region Earthquake of 29 September 2009 Global Seismographic Network M a r s Epicentral Region h a M A R S H A L L l I S TL A eN DcS tonic Setting l 174° 176° 178° 180° 178° 176° 174° 172° 170° 168° 166° C e n t r a l 160° 170° I 180° 170° 160° 150° s l a P a c i f i c K M e l a n e s i a n n L NORTH a d B a s i n i p B a s i n s n Chris tmas Island i H e BISMARCK n C g I R N s PLATE a l B R I TA i G E I s E W N T R 0° m a 0° N E R N e i n P A C I F I C 10° 10° C a H l T d b r s a e r C P L A T E n t E g I D n e i s A o Z l M e a t u r SOUTH n R r a c d E K I R I B A T I s F s K g o BISMARCK l a p a PLATE P A C I F I C G a Solomon Islands P L A T E S O L O M O N T U V A L U V I T Y I S L A N D S A Z TR FUTUNA PLATE 12° 12° S EN O U C BALMORAL C 10° T H H o 10° S O REEF o WOODLARK L Santa k O M Cruz PLATE I PLATE O N T RE N C H Sam sl Is lands oa I NIUAFO'OU a N s n C o r a l S e a S A M O A lan d SOLOMON SEA O ds PLATE s T U B a s i n R A M E R I C A N (N A PLATE T M H . -
Mylonitization Temperatures and Geothermal Gradient from Ti-In
Solid Earth Discuss., https://doi.org/10.5194/se-2018-12 Manuscript under review for journal Solid Earth Discussion started: 7 March 2018 c Author(s) 2018. CC BY 4.0 License. Constraints on Alpine Fault (New Zealand) Mylonitization Temperatures and Geothermal Gradient from Ti-in-quartz Thermobarometry Steven Kidder1, Virginia Toy2, Dave Prior2, Tim Little3, Colin MacRae 4 5 1Department of Earth and Atmospheric Science, City College New York, New York, 10031, USA 2Department of Geology, University of Otago, Dunedin, New Zealand 3School of Geography, Environment and Earth Sciences, Victoria University of Wellington, Wellington, New Zealand 4CSIRO Mineral Resources, Microbeam Laboratory, Private Bag 10, 3169 Clayton South, Victoria, Australia Correspondence to: Steven B. Kidder ([email protected]) 10 Abstract. We constrain the thermal state of the central Alpine Fault using approximately 750 Ti-in-quartz SIMS analyses from a suite of variably deformed mylonites. Ti-in-quartz concentrations span more than an order of magnitude from 0.24 to ~5 ppm, suggesting recrystallization of quartz over a 300° range in temperature. Most Ti-in-quartz concentrations in mylonites, protomylonites, and the Alpine Schist protolith are between 2 and 4 ppm and do not vary as a function of grain size or bulk rock composition. Analyses of 30 large, inferred-remnant quartz grains (>250 µm), as well as late, cross-cutting, chlorite-bearing 15 quartz veins also reveal restricted Ti concentrations of 2-4 ppm. These results indicate that the vast majority of Alpine Fault mylonitization occurred within a restricted zone of pressure-temperature conditions where 2-4 ppm Ti-in-quartz concentrations are stable. -
Geophysical Structure of the Southern Alps Orogen, South Island, New Zealand
Regional Geophysics chapter 15/04/2007 1 GEOPHYSICAL STRUCTURE OF THE SOUTHERN ALPS OROGEN, SOUTH ISLAND, NEW ZEALAND. F J Davey1, D Eberhart-Phillips2, M D Kohler3, S Bannister1, G Caldwell1, S Henrys1, M Scherwath4, T Stern5, and H van Avendonk6 1GNS Science, Gracefield, Lower Hutt, New Zealand, [email protected] 2GNS Science, Dunedin, New Zealand 3Center for Embedded Networked Sensing, University of California, Los Angeles, California, USA 4Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Kiel, Germany 5School of Earth Sciences, Victoria University of Wellington, Wellington, New Zealand 6Institute of Geophysics, University of Texas, Austin, Texas, USA ABSTRACT The central part of the South Island of New Zealand is a product of the transpressive continental collision of the Pacific and Australian plates during the past 5 million years, prior to which the plate boundary was largely transcurrent for over 10 My. Subduction occurs at the north (west dipping) and south (east dipping) of South Island. The deformation is largely accommodated by the ramping up of the Pacific plate over the Australian plate and near-symmetric mantle shortening. The initial asymmetric crustal deformation may be the result of an initial difference in lithospheric strength or an inherited suture resulting from earlier plate motions. Delamination of the Pacific plate occurs resulting in the uplift and exposure of mid- crustal rocks at the plate boundary fault (Alpine fault) to form a foreland mountain chain. In addition, an asymmetric crustal root (additional 8 - 17 km) is formed, with an underlying mantle downwarp. The crustal root, which thickens southwards, comprises the delaminated lower crust and a thickened overlying middle crust. -
Circulation and Mixing in Greater Cook Strait, New Zealand
OCEANOLOGICA ACTA 1983- VOL. 6- N" 4 ~ -----!~- Cook Strait Circulation and mixing Upwelling Tidal mixing Circulation in greater Cook S.trait, Plume Détroit de Cook Upwelling .New Zealand Mélange Circulation Panache Malcolm J. Bowrnan a, Alick C. Kibblewhite b, Richard A. Murtagh a, Stephen M. Chiswell a, Brian G. Sanderson c a Marine Sciences Research Center, State University of New York, Stony Brook, NY 11794, USA. b Physics Department, University of Auckland, Auckland, New Zealand. c Department of Oceanography, University of British Columbia, Vancouver, B.C., Canada. Received 9/8/82, in revised form 2/5/83, accepted 6/5/83. ABSTRACT The shelf seas of Central New Zealand are strongly influenced by both wind and tidally driven circulation and mixing. The region is characterized by sudden and large variations in bathymetry; winds are highly variable and often intense. Cook Strait canyon is a mixing basin for waters of both subtropical and subantarctic origins. During weak winds, patterns of summer stratification and the loci of tidal mixing fronts correlate weil with the h/u3 stratification index. Under increasing wind stress, these prevailing patterns are easily upset, particularly for winds b1owing to the southeasterly quarter. Under such conditions, slope currents develop along the North Island west coast which eject warm, nutrient depleted subtropical water into the surface layers of the Strait. Coastal upwelling occurs on the flanks of Cook Strait canyon in the southeastern approaches. Under storm force winds to the south and southeast, intensifying transport through the Strait leads to increased upwelling of subsurface water occupying Cook Strait canyon at depth. -
Review of Tsunamigenic Sources of the Bay of Plenty Region, GNS Science Consultancy Report 2011/224
DISCLAIMER This report has been prepared by the Institute of Geological and Nuclear Sciences Limited (GNS Science) exclusively for and under contract to Bay of Plenty regional Council. Unless otherwise agreed in writing by GNS Science, GNS Science accepts no responsibility for any use of, or reliance on any contents of this Report by any person other than Bay of Plenty regional Council and shall not be liable to any person other than Bay of Plenty regional Council, on any ground, for any loss, damage or expense arising from such use or reliance. The data presented in this Report are available to GNS Science for other use from June 2012. BIBLIOGRAPHIC REFERENCE Prasetya, G. and Wang, X. 2011. Review of tsunamigenic sources of the Bay of Plenty region, GNS Science Consultancy Report 2011/224. 74 p. Project Number: 410W1369 Confidential 2011 CONTENTS EXECUTIVE SUMMARY ....................................................................................................... VII 1.0 INTRODUCTION .......................................................................................................... 1 2.0 OVERVIEW OF PREVIOUS STUDIES ........................................................................ 1 2.1 Joint Tsunami Research Project of EBOP and EW (Bell et al. 2004) ............................ 1 2.2 Tsunami Source Study (Goff et al. 2006) ....................................................................... 4 2.2.1 Mw 8.5 Scenarios.............................................................................................. 5 2.2.1.1 -
Constraints on Alpine Fault (New Zealand) Mylonitization Temperatures and the Geothermal Gradient from Ti-In-Quartz Thermobarometry
Solid Earth, 9, 1123–1139, 2018 https://doi.org/10.5194/se-9-1123-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. Constraints on Alpine Fault (New Zealand) mylonitization temperatures and the geothermal gradient from Ti-in-quartz thermobarometry Steven B. Kidder1, Virginia G. Toy2, David J. Prior2, Timothy A. Little3, Ashfaq Khan1, and Colin MacRae4 1Department of Earth and Atmospheric Science, City College New York, New York, 10031, USA 2Department of Geology, University of Otago, Dunedin, New Zealand 3School of Geography, Environment and Earth Sciences, Victoria University of Wellington, Wellington, New Zealand 4CSIRO Mineral Resources, Microbeam Laboratory, Private Bag 10, 3169 Clayton South, Victoria, Australia Correspondence: Steven B. Kidder ([email protected]) Received: 22 February 2018 – Discussion started: 7 March 2018 Revised: 28 August 2018 – Accepted: 3 September 2018 – Published: 25 September 2018 Abstract. We constrain the thermal state of the central when more fault-proximal parts of the fault were deforming Alpine Fault using approximately 750 Ti-in-quartz sec- exclusively by brittle processes. ondary ion mass spectrometer (SIMS) analyses from a suite of variably deformed mylonites. Ti-in-quartz concentrations span more than 1 order of magnitude from 0.24 to ∼ 5 ppm, suggesting recrystallization of quartz over a 300 ◦C range in 1 Introduction temperature. Most Ti-in-quartz concentrations in mylonites, protomylonites, and the Alpine Schist protolith are between The Alpine Fault is the major structure of the Pacific– 2 and 4 ppm and do not vary as a function of grain size Australian plate boundary through New Zealand’s South Is- or bulk rock composition. -
GEOTECHNICAL RECONNAISSANCE of the 2011 CHRISTCHURCH, NEW ZEALAND EARTHQUAKE Version 1: 15 August 2011
GEOTECHNICAL RECONNAISSANCE OF THE 2011 CHRISTCHURCH, NEW ZEALAND EARTHQUAKE Version 1: 15 August 2011 (photograph by Gillian Needham) EDITORS Misko Cubrinovski – NZ Lead (University of Canterbury, Christchurch, New Zealand) Russell A. Green – US Lead (Virginia Tech, Blacksburg, VA, USA) Liam Wotherspoon (University of Auckland, Auckland, New Zealand) CONTRIBUTING AUTHORS (alphabetical order) John Allen – (TRI/Environmental, Inc., Austin, TX, USA) Brendon Bradley – (University of Canterbury, Christchurch, New Zealand) Aaron Bradshaw – (University of Rhode Island, Kingston, RI, USA) Jonathan Bray – (UC Berkeley, Berkeley, CA, USA) Misko Cubrinovski – (University of Canterbury, Christchurch, New Zealand) Greg DePascale – (Fugro/WLA, Christchurch, New Zealand) Russell A. Green – (Virginia Tech, Blacksburg, VA, USA) Rolando Orense – (University of Auckland, Auckland, New Zealand) Thomas O’Rourke – (Cornell University, Ithaca, NY, USA) Michael Pender – (University of Auckland, Auckland, New Zealand) Glenn Rix – (Georgia Tech, Atlanta, GA, USA) Donald Wells – (AMEC Geomatrix, Oakland, CA, USA) Clint Wood – (University of Arkansas, Fayetteville, AR, USA) Liam Wotherspoon – (University of Auckland, Auckland, New Zealand) OTHER CONTRIBUTORS (alphabetical order) Brady Cox – (University of Arkansas, Fayetteville, AR, USA) Duncan Henderson – (University of Canterbury, Christchurch, New Zealand) Lucas Hogan – (University of Auckland, Auckland, New Zealand) Patrick Kailey – (University of Canterbury, Christchurch, New Zealand) Sam Lasley – (Virginia Tech, Blacksburg, VA, USA) Kelly Robinson – (University of Canterbury, Christchurch, New Zealand) Merrick Taylor – (University of Canterbury, Christchurch, New Zealand) Anna Winkley – (University of Canterbury, Christchurch, New Zealand) Josh Zupan – (University of California at Berkeley, Berkeley, CA, USA) TABLE OF CONTENTS 1.0 INTRODUCTION 2.0 SEISMOLOGICAL ASPECTS 3.0 GEOLOGICAL ASPECTS 4.0 LIQUEFACTION AND LATERAL SPREADING 5.0 IMPROVED GROUND 6.0 STOPBANKS 7.0 BRIDGES 8.0 LIFELINES 9.0 LANDSLIDES AND ROCKFALLS 1. -
The Age and Origin of Miocene-Pliocene Fault Reactivations in the Upper Plate of an Incipient Subduction Zone, Puysegur Margin
RESEARCH ARTICLE The Age and Origin of Miocene‐Pliocene Fault 10.1029/2019TC005674 Reactivations in the Upper Plate of an Key Points: • Structural analyses and 40Ar/39Ar Incipient Subduction Zone, Puysegur geochronology reveal multiple fault reactivations accompanying Margin, New Zealand subduction initiation at the K. A. Klepeis1 , L. E. Webb1 , H. J. Blatchford1,2 , R. Jongens3 , R. E. Turnbull4 , and Puysegur Margin 5 • The data show how fault motions J. J. Schwartz are linked to events occurring at the 1 2 Puysegur Trench and deep within Department of Geology, University of Vermont, Burlington, VT, USA, Now at Department of Earth Sciences, University continental lithosphere of Minnesota, Minneapolis, MN, USA, 3Anatoki Geoscience Ltd, Dunedin, New Zealand, 4Dunedin Research Centre, GNS • Two episodes of Late Science, Dunedin, New Zealand, 5Department of Geological Sciences, California State University, Northridge, Northridge, Miocene‐Pliocene reverse faulting CA, USA resulted in short pulses of accelerated rock uplift and topographic growth Abstract Structural observations and 40Ar/39Ar geochronology on pseudotachylyte, mylonite, and other Supporting Information: fault zone materials from Fiordland, New Zealand, reveal a multistage history of fault reactivation and • Supporting information S1 uplift above an incipient ocean‐continent subduction zone. The integrated data allow us to distinguish • Table S1 true fault reactivations from cases where different styles of brittle and ductile deformation happen • Figure S1 • Table S2 together. Five stages of faulting record the initiation and evolution of subduction at the Puysegur Trench. Stage 1 normal faults (40–25 Ma) formed during continental rifting prior to subduction. These faults were reactivated as dextral strike‐slip shear zones when subduction began at ~25 Ma. -
Identifying Resource Management Conflicts: Stakeholder Study Regarding Flood Protection in Wairarapa Moana
Identifying Resource Management Conflicts: Stakeholder Study Regarding Flood Protection in Wairarapa Moana Sponsored By: Breanne Happell René Jacques Elizabeth van Zyl Elizabeth Walfield Identifying Resource Management Conflicts: Stakeholder Study Regarding Flood Protection in Wairarapa Moana An Interactive Qualifying Project Submitted to the Faculty of Worcester Polytechnic Institute In partial fulfillment of the requirements for the Degree of Bachelor of Science In cooperation with The Greater Wellington Regional Council Submitted on March 1st, 2016 Submitted By: Breanne Happell René Jacques Elizabeth van Zyl Elizabeth Walfield Project Advisors: Bethel Eddy Robert Kinicki This report represents work of WPI undergraduate students submitted to the faculty as evidence of a degree requirement. WPI routinely publishes these reports on its web site without editorial or peer review. For more information about the projects program at WPI, see http://www.wpi.edu/Academics/Projects i Abstract This project aided the Greater Wellington Regional Council (GWRC) in gathering the opinions of stakeholders in regards to two flood protection methods in the Lower Wairarapa Valley of New Zealand: the Geoffrey Blundell Barrage Gates and the Ruamahanga River Cutoff. These methods regulate water levels in Lake Wairarapa. The team conducted 25 interviews with flood protection managers, farmers that live in the valley, and members of Ngāti Kahungunu, a Māori iwi (tribe). Our analysis found that fish passage through the gates, lake water levels, and whether the GWRC incorporated stakeholder opinions fairly were areas of concern to the stakeholder groups. This information will help to facilitate further communication between the stakeholder groups and the GWRC. ii Executive Summary This project evaluated the various views on the management of the Geoffrey Blundell Barrage Gates and the Ruamahanga River Cutoff, two flood protection methods implemented in Wairarapa Moana. -
Marlborough Civil Defence Emergency Management Plan
Marlborough Civil Defence Emergency Management Plan 2018-2023 Seddon Marlborough Civil Defence Emergency Management Group Improving the resilience of the District to all foreseeable emergency events through the active engagement of communities and the effective integration of support agencies. Contents Glossary of Terms ...................................................................................................1 1. Introduction ...................................................................................................4 1.1 Setting the Scene......................................................................................................... 4 1.2 The Marlborough Context ............................................................................................ 5 1.3 National Context .......................................................................................................... 9 1.4 Marlborough CDEM Vision and Goals ....................................................................... 10 2. Marlborough’s Risk Profile ........................................................................ 11 2.1 Introduction ................................................................................................................ 11 2.2 Detailed Risk Analysis ............................................................................................... 12 2.3 Marlborough CDEM Group Environment ................................................................... 18 3. Reducing Marlborough’s Hazard Risks ................................................... -
The Tectonic Evolution of Pegasus Basin and the Hikurangi Trench, Offshore New Zealand
THE TECTONIC EVOLUTION OF PEGASUS BASIN AND THE HIKURANGI TRENCH, OFFSHORE NEW ZEALAND by Sarah E. King A thesis submitted to the Faculty and the Board of Trustees of the Colorado School of Mines in partial fulillment of the requirements for the degree of Master of Science (Geology). Golden, Colorado Date:_________________ Signed:_________________________ Sarah E. King Signed:_________________________ Dr. Bruce Trudgill Thesis Advisor Golden, Colorado Date _________________ Signed:_________________________ Dr. M. Stephen Enders Professor and Interim Department Head Department of Geology and Geological Engineering ii ABSTRACT The Pegasus Basin overlies part of the tectonic transition between oblique southwest subduction of the Paciic Plate below the East Coast of the North Island of New Zealand, and the strike-slip faulting that dominates the majority of the South Island of New Zealand. The transition from this strike-slip zone into the actively subducting Hikurangi Trench requires a signiicant translation of plate motion from margin parallel to margin normal within the Pegasus Basin. The purpose of this research was to understand the distribution of strain along this complex transition, and to identify how shortening is manifested on structures through time. The diferent stress regimes along the coast may correspond to diferent shortening amounts absorbed on a variety of structures that translate strain accommodation through the major tectonic transition from compressional subduction to strike-slip displacement. Interpretations of 2D seismic proiles guided by models of margins with comparable tectonic settings ensure geologically restorable interpretations and reasonable shortening values within this transition zone. Restorations of depth converted seismic cross sections constrain ages of the faults and establish controls on their timing and activation.