Geology of the Nelson Area
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GEOLOGY OF THE NELSON AREA M.S. RATTENBURY R.A. COOPER M.R.JOHNSTON (COM PI LERS) ....., ,..., - - .. M' • - -- Ii - -- M - - $ I e .. • • • ~ - - 1 ,.... ! • .- - - - f - - • I .. B - - - - • 'M • - I- - -- -n J ~ :; - - - " - , - " • ~ I • " - - -- ...- •" - -- ,u h ... " - ... ," I ~ - II I • ... " -~ k ". -- ,- • j " • • - - ~ I• .. u -- .. .... I. - ! - ,. I'" 3ii:: - I_ M wiI ~ .0 ~ - ~ • ~ ~ •• I ---, - - .. 0 - • • 1~!1 - , - eo - - ~ J - M - I - .... • - .. -~ -- • ,- - .. - M , • • I .. - eo -- ~ .1 - ~ - ui J -~ ~ •• , - i - - ~ • c--,- 1.10 ___ - ) ~ - .... - ~ - - 1 - -- ~ - '" - ~ ~ .. •• ~ - M - I Ito--...., •• ..-. - II - - - M ~ - I - • - 11, - • • ,- ~ - - ,e - ~ , • - ~ __- [iij.... i _ ... • ~ ~ - - ~ • "-' .. -- h ~ 1 I ~ ~ - - ~ - - • Interim New Zealand ,- 0.- ~ ~ , M ~ - geological time scale from ~ - Crampton & others (1995), " .... - ~ "I ~ •• , I - with geochronology after - , Gradslein & O9g (1996) - -- and Imbrie & others (1984). GEOLOGY OF THE NELSON AREA Scale 1:250 000 M.S. RATTENBURY R.A. COOPER M.R. J OHNSTON (COMPILERS) Institute of Geologica l & N uclear Sciences 1:250000 geological map 9 Institute of Geological & Nuclear Sciences Limited Lower Hutt, New Zealand 1998 BIB LIOG RAPHIC REFEREN CE Ra ttcnbury, M.S., Cooper. R,A .• Johnston. M.R. (co mpilers) 1998. Geology of the Nelson area. Ins titute of Geological & Nuclear Sciences 1:250000 geological map 9. 1sheet + 67 p. Lower HUll, New Zealand : Instit ute ofOeological & Nuclear Sciences Li mited. Includes mapping, compilation, and a contribution to the text by S. Nathan. GIS operations by D.W. Heron, M.S. Ranenbury, and l .A. Lyall. Ediled, designed, and prepared fo r publication by A. M. Sherwood, D.W. Heron and S. Nepe Printed by Graphic Press & Packaging LId, Levin ISBN 0-478-09623-2 © Copyright Institute of Geological & uclear Sciences Limited 1998 FRONTCQVER Nelson City lies in the foothills between the Permian to Cretaceous basement terranes ofthe Bryant Range (lerl) and the thick Pliocene 10 Quatemary sediments that have been down-faulted to form the Moulere Depression (right). The city area also contains remnants of a successionofEocene to Miocene sedimentary rocks. Widespread Mesozoic and Cenozoic faulting , including presently active fau lts of the Wai mca·Flaxmore Fault Syste m. have disrupted the older rocks :md locally influenced the deposition of youn ger sedi ments. The Boulder Bank (right) forms a na tural barrier to Nelson Have n and is one of several promi ne nt barrier spits within the Tas man Bay are<! . Plloto CN32833: D.L HOllier CONTENTS ABSTRACT Permian to Triassic schistose rocks 34 Key words rfrianic melange 36 Torlesse terrane 36 INTRO DUCTION _._.__ ____.. 1 Triassic schistose rocks 37 Late Jurassic to Early Cretaceous sedimentary THE QMAP SERIES 1 rocks 38 The QMAP geographic infonnation system 1 DoHa sources I CRETACEOUS TO EARLY PLEISTOCENE 38 Reliability I Late Cretaceous to Paleocene sediments 39 Paleocene to Eocene sediments 40 REG10NALSElTING 4 Oligocene to earl iest Miocene sediments 41 Early to Middle Miocene sediments 42 GEOMORPHOLOGy....... 5 Late Miocene to Pliocene sedimen ts . 44 Moutere Depression . 5 Late Pliocene to early Pleistocene sedi ments 44 Tasman Moun tains 5 Structure 45 Wairau valley 5 Richmond Range 5 QUATERNARY 46 Farewell Spil 5 Al lu vial terrace and flood plain deposits 46 Boulder Bank 5 Alluvial fan deposits 47 Lakes 5 Marine deposits 47 Sea bed morphology 5 Sand dunes and marine sand deposits 47 Peat and swamp deposits 47 STRA TIGRAPHY _..•• ~ ~•••••••••••..... __.. 8 Landslide deposits 48 Deposits of human origin 48 CAMBRIAN TO DEVONIAN 8 Structure 48 Buller terrane 8 Late Cambrian to Early Ordovician OFFSHORE GEOLOGy 48 sedimentary rocks 8 Early to Lale Ordovician sedimentary rocks 8 GEOLOG ICAL RFSOURCFS •••.....•••••_ __ 51 Structure and metamorphism 9 Takaka terrane I I Gold 51 Middle 10 Late Cambrian sedimenlary 3nd Other metal lic minerals 51 igneous rocks ... 14 Coal 52 L3te C3mbri 3n melange 3nd mct3morphi c roc ks 16 Other non·metallic minerals and rocks .. 54 L3tcsl Cambri3 n to Early Devoni3n sedi mentary Oil and gas .. 55 rocks ... ................ 17 Ground water 55 Struc ture 3nd metamorph ism 17 ENGINEERING GEOL.OGY 56 Tecto/lie Ilistory 21 Late Devoni3n inlrusive rocks 22 Paleozoic to Mesozoic rocks 56 Tertiary sedimentary rocks 56 CARBONIFEROUS TO EARLY Quaternary sediments 56 CRETACEOUS 24 Lale Pennian to Early Triassie sedimentary rocks .. 24 G EOL.OCICAL. I-IA ZARDS 57 Late Jurassic to Early Cretaceous intrusive rocks 24 Median T«tonic Zone 26 Landsliding 57 Carboniferous 10 Early Cretaceous intrusive Seismotec:tonic hazard 57 and sedimentary rocks 27 Coastal erosion 58 Brool: Slreet urrane 28 Tsunami 58 Permian volcanic and sedimentary rocks 28 AVAI L.AB IL.lTY OF QMA PDATA 59 Murihiku terrane 29 Triassie sedimentary rocks 29 ACKNOWL.EDGMENTS ~ 59 Dun Moulltain·Maitai terrane 30 Permian ultramafic and mafic igneous roc ks 30 REFERENCFS 60 E3 r1 y Permian to Triassic sedimentary rocks 32 Caples terrane . 34 APPENDIX Permian to Triassic sedimentary roc ks 34 Cambrian stra tigraphy of the T3kaka terrane 67 ABSTRACT , The Nelson 1:250 (XX) geok>gical map CQver.; 11550kin of Ultramafics Group, the Permian mafi c igneous the grealer Nelson land atta and part of Marlborough in Livingstone Volcantcs Group. and the d3StK: sedimentary the northwest ofthc South Island. New Zealand. The area and carbonate rocks of the Middle Permi3n to Early comprises rugged. rea:ntly deglaciated Tasm3n Mountains Triassic Maitai Group. The Patuki Melange marks the in the west and the lower Richmond Range and other tectonic boundary between the Maitai Group and the ranges in tbe east separated by the down-faulted low Caples Group of the Caples terrane. The Caples Group lying Moutere Depression. In the southeast. the Wairau is dominated by Permo-Triassic volcaniclastic valley separates the Richmond Ra nge from the southern sedimentary rock which becomes increasingly schistose Marl borough mountain ranges. The offshore pan of the to the southeast. The Marl borough Schist Zone Nelson QMAP area is characteri sed by relatively shall ow incorporates the sut ure between the Caples terrane and water depths. the quanzofeldspathic schist ofthe Torlesse terrane. The schi stose component of the Torl esse terrane in The Paleozoic Buller and Takaka terranes, separated by Marlborough is part of the 'rrri assic Rakaia subterrane. the Amlloki Faull, and plutonic intrusi ve rocks form the separated by th e Alpine Fault from the low grade Early geological basement in the wes tern halfof the map area. Cretaceous Pahau subterrane sandstone and mudstone. The Buller terrane conta ins Ordovician Greenla nd Group and Golden Bay Group me tasedimentary turbidites. A regional unconformity separates Late Cretaceous and extensively intruded by the Late Devonian-Carboni ferous younger rocks from the indu rated basement . Late Karamea Suite granitoids and to a lesser extent, the Early Cretaceous to early Eocene sedimentary basins in which Cretaceous Separation Point Suite granitoids.To the east. the thick Pakawau and Kapuni groups were deposited the lower sequence of the Takaka terrane comprises a developed in the northwest in response to rifting along lower sequence ofCambrian volcanic and volcaniclastic north-trending faults . The late Eocene saw widespread arc·related sedimentary rocks (Devil River Volcanics deposition of the generally thinner terrestrial Brunner Group and Haupiri Group). their metamorphosed Coal Measures and shallow water Kaiata Formation, equivalents (Waingaro Schist). and a prominent melange followed by limestone and calcareous sediments of the unit (Balloon Melange). The overlying upper sequence Nile Group in the Oligocene. Renewed tectonism in the is a Late Cambrian to Early Devonian passive margin Miocene resulled incompressional revenal ofCretaceous succession of clastic and carbonate sedimentary rocks fa ults and inversion of some of the older basins (Mount Patriarch Group. Mount Arthu r Group, Ellis accompanied by widespread deposition of terrigenous Group, and Baton Group). The Takaka terrane has been muddy sediments of the Lower Blue BOllom Group. intruded by the Late Devonian maficJultramafic Riwaka Muc h of the area was emergent during the late Miocene Complex and Separation Point Suite granitoids. The and Pliocene with depositionconfined to localised basins. Takaka terrane is struct ura ll y complex, compri si ng a Rapid upl ift ofthe Southern Alps and Spenser Mountains num ber of fault slices exhibiting varying amounts of in the Plio-Pleistocene resulted in substantial vo lu mes layer-parallel thrust im brica tio n. subsequent fo ldi ng. and of gravels being deposited. incl udi ng the volu minous strike-slip fa ulling. The Buller and Takaka terranes were Moutere Gravel no w preserved in the Moutere amalgamated to form the Tuhua terrane in the Early Depression. Middle Devonian. Numerous outwash gravels and marine incursions The eastern basement comprises the Median Tectonic occurred between and during the Pleistocene glaciations Zone and the Brook Street, Murihiku, Dun Mountain followed by extensive postglacial alluvial and marine Maitai, Caples. and Torlesse terranes. The Median deposition in the Holocene. Continuing tectonism from Tectonic Zone. which underlies much of the Moutere the Pacific-Australia plate convergence has resulted in Depression. is dominated by Jurassic to Cretaceous the mountainous topography. Active faults include the igneous suites including Ihe ROioroo