Geology of the Kaikoura Area - GNS Science

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290PermianCarboniferous354Late Devonian370391417EarlyCretaceousJurassicTriassicMiddleDevonianEarlyDevonianRahu Suite*Kirwans Dolerite*Topfer Formation*Karamea SuiteReefton Group*TUHUA TERRANEParapara Group*Riwaka Complex*Terrane amalgamationBaton Group*Separation PointSuiteTasmanIntrusivesGlenroyComplexRotoroaComplexMEDIANBATHOLITHPepin Group*KARAMEA SUITEMURIHIKUTERRANERichmond GroupBrook StreetVolcanicsGroupBROOKSTREETTERRANEMaitaiGroupLivingstoneVolcanics GroupDun MountainUltramafics GroupDUNMOUNTAIN-MAITAITERRANEBROOK STTERRANECaplesGroupCAPLESTERRANEMURIHIKUTERRANETORLESSECOMPOSITETERRANEungroupedRAKAIATERRANEEskHeadBeltDUN MOUNTAIN-MAITAI TERRANE CAPLES TERRANEungroupedPAHAUTERRANE443SilurianNOrdovician490Golden BayGroup*Greenland GroupEllis Group*Mount ArthurGroupm e505LateCambrianMiddleCambrianBULLERTERRANEDevilRiverVolcanicsGroup*l a n g e e v e n tHaupiriGroupMEDIANBATHOLITHESKHEADBELTPAHAUTERRANEine ( rau) ltFauAlp WaiTAKAKATERRANEWesternProvinceBULLERTERRANERAKAIATERRANEEasternProvinceTAKAKATERRANEESKHEADBELTPAHAUTERRANEAwatere Fault20 kmFigure 14 Tectonostratigraphic relationships within and between basement terranes. Stratigraphic units not appearing on the Kaikoura map are marked with an asterisk.12
STRATIGRAPHYCambrian to Cretaceous basement rocks, includingvolcanic, metasedimentary, granitic and ultramafic rocks,outcrop over 70% of the Kaikoura map area. The basementrocks are overlain by remnants of Late Cretaceous andCenozoic, terrestrial and marine, sedimentary and igneousrocks, preserved in basins around Murchison andthroughout eastern Marlborough and northern Canterbury.In the east these younger rocks contain local volcanicsequences. Quaternary fluvioglacial and alluvial depositsare widespread but Quaternary marine rocks occur onlylocally.CAMBRIAN TO CRETACEOUSThe basement rocks of the Kaikoura map area, ofGondwanaland origin, have been divided into the largelyearly Paleozoic Western Province and the late Paleozoic toMesozoic Eastern Province (Landis & Coombs 1967). Thevolcano-sedimentary and mafic intrusive rocks are mappedin tectonostratigraphic terranes (Figs 4, 14; Coombs &others 1976; Bishop & others 1985; Bradshaw 1993;Mortimer 2004) within which traditional lithostratigraphicformations and groups are recognised. The WesternProvince contains the Buller and Takaka terranes (Cooper1989) that amalgamated in the mid-Devonian (collectivelytermed the Tuhua composite terrane). The Eastern Provincein the Kaikoura map area comprises the Brook Street, DunMountain-Maitai, Murihiku, and Caples terranes west ofthe Alpine Fault and the Rakaia and Pahau terranes(collectively the Torlesse composite terrane) east of thefault (Coombs & others 1976; Mortimer 2004). Many of theplutonic rocks occur within the originally contiguousMedian and Karamea batholiths (Tulloch 1988; Mortimer& others 1999).Buller terraneEarly Ordovician sedimentary rocksThe Buller terrane, comprising the Greenland Group (|g)within the Kaikoura map area, occupies a few squarekilometres near Maruia Saddle. The group consists of welltopoorly bedded, greenish-grey quartzose sandstone andmudstone (Stewart 1974). The rocks are intruded by LateDevonian-Carboniferous Karamea Suite granite in thenorthwest and faulted against Miocene conglomerate tothe southeast. Greenland Group sandstone typicallycontains abundant detrital quartz, minor sodic plagioclaseand subordinate volcanic and sedimentary rock fragments(Nathan 1976; Roser & others 1996). The group has beeninterpreted as a turbidite succession within a submarinefan deposit (Laird 1972; Laird & Shelley 1974). Graptolitesfrom near Reefton, 30 km west of the Kaikoura map area,are early Ordovician (Cooper 1974). K-Ar and Rb-Sr agesfrom Greenland Group beyond the map area indicate awidespread Late Ordovician to Early Silurian greenschistfacies (chlorite zone) metamorphic event (Adams & others1975; Adams 2004). Adjacent to the granite, the group hasbeen thermally metamorphosed to biotite hornfels (Stewart1974). Metamorphism probably accompanied deformationthat resulted in generally steep bedding dips, tight uprightfolds and a penetrative cleavage (Rattenbury & Stewart2000).Takaka terraneA small area of the Takaka terrane outcrops in the Kaikouramap area along the Alpine Fault, near Lake Daniells. Furthernorth the terrane is concealed by Tertiary rocks in theMurchison Basin (see section C-C’), but is well exposed inNorthwest Nelson, where the type localities of the Haupiriand Mt Arthur groups are located (Rattenbury & others1998). Southwest of the Kaikoura map area, the terraneprogressively narrows and is truncated by the Alpine Fault(Nathan & others 2002).Middle Cambrian to Late Ordovician sedimentary rocksIn the vicinity of Lake Daniells, volcanogenic sedimentaryrocks with conglomerate and minor basaltic flows arecorrelated with the Haupiri Group of Northwest Nelson(Münker & Cooper 1999; Nathan & others 2002). Threeinformal units (Nathan & others 2002) are recognised,comprising dolomitic mudstone and ankeritic sandstonewith minor conglomerate ($hr), polymict pebble to granuleconglomerate ($ha), and grey laminated dolomiticmudstone and sandstone with widespread interlayeredfelsic volcanic rocks ($hh). In Northwest Nelson the grouphas been assigned a Middle-Late Cambrian age (Münker& Cooper 1999).In the Lake Daniells area the Mt Arthur Group overlies theHaupiri Group (Bowen 1964), separated by a detachmentfault (R. A. Cooper in Nathan & others 2002). The SluiceBox Limestone (|ms) consists of recrystallised grey,commonly siliceous, limestone and minor sandstone withmudstone layers. Conodonts, trilobites and disarticulatedbrachiopods indicate a Late Cambrian to Middle Ordovicianage (Cooper 1989). The formation is correlated with theArthur Marble 1 and Summit Limestone formations ofNorthwest Nelson (Rattenbury & others 1998). Theconformably overlying siltstone and minor quartzsandstone of the Alfred Formation (|mw) contains LateOrdovician (Gisbornian) graptolites and is correlated withthe Wangapeka and Baldy formations in Northwest Nelson(Rattenbury & others 1998).Karamea BatholithLate Devonian to Early Carboniferous intrusive rocksThe Karamea Batholith extensively intrudes the Tuhuaterrane in the northwest of the South Island and isdominated by the Karamea Suite of Late Devonian-earlyCarboniferous granites (Tulloch 1988; Muir & others 1994).The suite has S-type geochemistry, commonly containingmuscovite and generally lacking hornblende. Within theKaikoura map area the rocks are only exposed at MtsNewton and Mantell, north and south of Murchisonrespectively, but are inferred to underlie much of thePaleogene-Miocene strata of the Murchison Basin. At MtNewton the suite comprises coarse-grained, inequigranular13
Page 1: 1 : 2 5 0 0 0 0 G e o l o g i c a l
Page 7: ABSTRACTThe Kaikoura 1:250 000 geol
Page 10 and 11: 27 10722181725814362333322621243128
Page 12 and 13: ProvinceSEDIMENTARY AND VOLCANIC RO
Page 14 and 15: Main Divide rangesGEOMORPHOLOGYThe
Page 16 and 17: Figure 9 Basin and range topography
Page 18 and 19: Figure 12 The active Alpine (Wairau
Page 22 and 23: iotite granite, locally with megacr
Page 24: interlayered with the Rotoroa Compl
Page 28 and 29: Figure 19 Maitai Group sedimentary
Page 30 and 31: Torlesse composite terraneThe Torle
Page 32 and 33: Permian to Late Triassic semischist
Page 34: Zones of intra-Pahau mélange, char
Page 37 and 38: CRETACEOUS TO PLIOCENEFollowing ama
Page 39 and 40: Figure 31 Interbedded sandstone and
Page 41 and 42: Figure 34 The Seymour Group include
Page 43 and 44: of feldspar-clinopyroxene-biotite-a
Page 45 and 46: The Amuri Limestone (Pza, Eza) is w
Page 47 and 48: overlies older rocks (Carter & Land
Page 49 and 50: Late Miocene to earliest Late Plioc
Page 51 and 52: QUATERNARYThe tectonic regime initi
Page 53 and 54: Figure 52 Screes on the southern fl
Page 55 and 56: Marine depositsMarine sand and grav
Page 57 and 58: and/or non-deposition (including th
Page 59 and 60: hydrous mica clay are widespread as
Page 61 and 62: Dunite boulders are sporadically co
Page 63 and 64: GEOLOGICAL HAZARDSParts of the Kaik
Page 65 and 66: The Modified Mercalli Intensity sca
Page 67 and 68: Table 2. Mean return periods for ea
Page 69 and 70: REFERENCESAdams, C.J. 2003: K-Ar ge
Page 71 and 72:
Childerhouse, S.J.; Dawson, S.M.; S
Page 73 and 74:
Holdaway, R.N.; Worthy, T.H. 1997:
Page 75 and 76:
McPherson, R.I. 1988: Experimental
Page 77 and 78:
Stewart, R.B. 1974: Geology of Mt M
Page 79:
This map and text illustrate the ge
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Geology of the Kaikoura Area - GNS Science

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