Late Cretaceous-Tertiary stratigraphy, structure, and tectonic history of the area between Whareama and Ngahape, eastern Wairarapa, New Zealand

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1 New Zealand Jurnal f Gelgy and Gephysics ISSN: (Print) (Online) Jurnal hmepage: Late Cretaceus-Tertiary stratigraphy, structure, and tectnic histry f the area between Whareama and Ngahape, eastern Wairarapa, New Zealand P. R. Mre T cite this article: P. R. Mre (1980) Late Cretaceus-Tertiary stratigraphy, structure, and tectnic histry f the area between Whareama and Ngahape, eastern Wairarapa, New Zealand, New Zealand Jurnal f Gelgy and Gephysics, 23:2, , DOI: / T link t this article: Published nline: 02 Feb Submit yur article t this jurnal Article views: 306 Citing articles: 6 View citing articles Full Terms & Cnditins f access and use can be fund at

2 N.Z. Jumal j Gelgy and Gephysics Vl. 23, N.2 (1980): Late Cretaceus:-Tertiary stratigraphy, structure, and tectnic histry f the area between Whareama and Ngahape, eastern Wairarapa, New Zealand P. R. MOORE New Zealand Gelgical Survey, DSIR, Lwer Hull ABSTRACT A NNE-striking belt f Late Cretaceus-Early Tertiary sediments in the area between Whareama and Ngahape cnsists f a sequence, frm base t tp, f: sandstne, cnglmerate, and minr siltstne (Glenburn Frmatin); thin-bedded sandstne and mudstne (Te Mai Frmatin); siltstne (Whangai Frmatin); black siltstne (Waipawa Frmatin); and glaucnitic sandstne (Huatkitki Frmatin). The belt is faulted against indurated, strngly defrmed Early Cretaceus sandstne and siltstne (Pahaa Grup) in the west, and verlain uncnfrmably by Late Tertiary (Micene) sediments in the east. Shallw intrusins f dlrite and basalt, and submarine basalt flws, cmprising the Ngahape Vlcanic Cmplex (new), ccur mstly in the upper part f the sequence. Vlcanic activity was prbably restricted t late Maastrichtian-early Palecene (Haumurian-Teurian) time. The Late Cretaceus-Early Tertiary frmatins are cnsidered t have been depsited in inner shelf r marine delta (Glenburn), tidal strait (Te Mai), and shallw restricted basin (Whangai and Waipawa) envirnments. Majr faults, including the new Mtuwaireka Fault, in the aa mstly trend NNE. Significant discveries with respect t faults are: repeated mvement (late Cretaceus, Plicene, and Recent?) n Adams Fault, frming the western bundary f the belt; a reverse cmpnent f mvement n the lw-angle ( ) west-dipping Pukerr Fault; and strike-slip (dextral) mvement n the ENE-trending Kaumingi Fault. Faulting and flding tk place during depsitin f Late Cretaceus-Early Tertiary sediments, resulting in penecntempraneus ersin and slumping. Majr tectnic upheaval ccurred in pst-late Palecene time, prbably in the early Ecene. KEYWORDS Cretaceus, Tertiary, stratigraphy, structure, igneus rcks, Wairarapa INTRODUCTION Cretaceus and early Cenzic sediments in eastern Wairarapa frm part f the East Cast fld and fault belt (Katz 1976). In recent years parts f this belt have been mapped by students f Victria University f Wellingtn in an effrt t unravel the cmplex stratigraphy and structure. The present study links mapping t the nrth by Jhnstn (1975; in press) with that t the suth by P. Wellman (1970), van den Heuvel (1960), and Eade (1966), and as a result enables a greater understanding f the tectnic histry f the fld and fault belt in Wairarapa. The area between Whareama and Ngahape cnstitutes part f the Ngaumu State Frest, and is mstly planted in extic species f pine. Access t the frest is either via Strnvar (frm Mastertn) r frm Hmewd Rad. The mapped area (Fig. 1) is cvered by NZMS 1 tpgraphic sheets N158, 162, and 163, and the equivalent NZMS 260 (metric) sheets T26 and T27. All grid references quted are in terms f the metric grid. Fssil lcalities are thse f the metricated N.Z_ Fssil Recrd File and cpies f recrd frms Me held by the Gelgy Department, Victria University f Wellingtn. STRATIGRAPHY Late Cretaceus-Early Tertiary (Raukumara-Dannevirke Series) sediments in the Whareama-Ngahape area frm a NNE-trending belt up t 6 km wide, faulted against Early Cretaceus rcks (Pahaa Grup) n the west, and uncnfrmably verlain by Late Tertiary sediments in the east. The belt cnsists f flded, faulted, steeply dipping, and mstly westward yunging strata. PAHAOA GROUP (Early Cretaceus) Highly defrmed, indurated alternating sandstne and siltstne, thick sandstne, and minr breccia and cnglmerate west f Adams Fault (Fig. 1) has been mapped as Pahaa Grup by Mre & Speden (1979). Tw frmatins are included in the grup by these authrs-mangapkia (new) and Taip Frmatin (Jhnstn 1975). Althugh the tw frmatins are nt differentiated n the map, alternating sandstne and siltstne f Mangapkia Frmatin frms a strip adjacent t Adams Fault in the nrthern and suthern parts f the area, and the sandstne-dminated Taip Frmatin underlies the area between Kaumingi Stream and Strnvar. A wedge f alternating beds als lies alng Kaumingi Fault. Beds f red-brwn and minr green mudstne r argillite up t 1-2 m thick, interpreted as tuffaceus hrizns by Mre & Speden (1979), are cmmn in the narrw strip f Pahaa Grup rcks suth f Strnvar. One bed in the headwaters f Te Maire Stream lies directly alng strike frm a small lens-shaped bdy f basalt (Kpi Bninite). Received 9 March 1979, revised 3 Octber 1979

3 168 N.Z. JOURNAL OF GEOLOGY AND GEOPHYSICS, VOL. 23, 1980 Other minr lithlgies include thick sandstne with lenses f cal; fine (nglmerate; and cnglmeratebreccia r "pebbly mudstne". Cncretins are rare. A few sandstne beds shw parallel and crss-laminatin, but grading was nt bserved. Pahaa Grup rcks in the area are discussed mre fully by Mre & Spe<ien (in prep.). Fssils and Age Fragments f Incerd1JlUS sp. indet. are generally the nly fssils fund. Hwever, a mre diverse fauna (T26/fI2) f Inceramus sp., Rtularia sp., a belemnite, and pssible barnacle plate was cllected frm siltstne within the crush zne alng Adams Fault at T26/ Diagnstic fssils cllected at ther lcalities, namely Inceramus d. warakius (T26/f23) and Aucellina euglypha Wds (T27/f6891), indicate a Mtuan age in part. The grup is cnsidered t range frm Urutawan t Mtuan by Mre & Speden (1979). The thin sliver f Ngaterian beds adjacent t Adams Fa ul t shwn n P. Wellman's (1970) ma"p was based n flat specimens f Inceramus?hakarius (T27/f6900). In a re-examinatin f Victria University cllectins frm this lcality Dr I. G. Speden (pers. cmm.) identified specimens f Inceramus sp. indet. and I. pe!ius Wellman. The latter came frm a lithlgically different sandstne bulder cllected by P. WelIman in The "Ngaterian" rcks mapped by P. Wellman (1970) are, therefre, f uncertain age, but n lithlgic and structmal criteria are cnsidered part f Pahaa Grup. Thickness Minimum thickness is prbably abut 1500 m. LATE CRETACEOUS-EARLY TERTIARY SEQUENCE The belt f late Cretaceus-Early Tertiary sediments east f Adams Fault cnsists f five frmatins (Fig. I)-Glenburn, Te Mai, Whangai, Waipawa, and Huatkitki-ranging in age frm Mangatanean (Raukumara Series) t Teurian (Dannevirke Series). The base f the sequence is faulted, and the tp either faulted r verlain uncnfrmably by late Tertiary sediments. Igneus sills, dikes, and flws (Ngahape Cmplex-see later) ccur in the three ldest frmatins (flws nly in the upper tw). GLENBURN Piripauan) FORMATION (Mangatanean-earIy Glenburn Frmatin was prpsed by Eade (1966) fr a thick sequence f graded-bedded carbnaceus sandstne and siltstne, thick siltstne, and cnglmerate in the Glenburn area. Cnglmerate was cnsidered characteristic. Jhnstn (1975) has since applied the name t a predminantly graded-bedded sequence, lacking cnglmerate, in the Tinui area. As redefined by Jhnstn, the frmatin includes the lngbush and part f the Tutu Frmatins f Eade (1966). In the Whareama-Ngahape area, a thick highly cnglmeratic unit underlying Te Mai Frmatin (f Jhnstn 1975) is equated with Glenburn Frmatin as riginally defined by Eade (1966). Althugh graded beds cnstitute nly a minr part f the sequence, it is cnvenient t use a pre-existing name at this stage, rather than erect a new frmatin. Glenburn Frmatin in the mapped area cnsists f thick-bedded, parallel and crss-laminated carbnaceus sandstne, cnglmerate and breccia-cnglmerate, thinbedded sandstne, and dark grey siltstne. Thick-bedded FIG. 2-Glenburn Frmatin: a 2-m-thick zne f thin-bedded sandstne and minr siltstne (graded beds) within thick, parallellaminated carbnaceus sandstne (bttm left and upper right), Kaiwhata Stream, T27/ Thin-bedded zne cntains scattered, thin-shelled Inceramus (1. petius?) and a few sideritic cncretins. Beds dip 60 NW and face west (t right f pht).

4 50\ '-- 5;l 14 wtw".ataiq n"""''''', imi*-... u"'_ IlUi1,T(Il(ilOl(llWflJ. 6rty,'I''IItIII[am: _ WAJPAWA III H:: }I } I DM.-.I_"' wiih-a- i -. 0> j v.- witti,,",bn&.""',..... _.. ::::.m.*'.:l::':ia- liiiii.... ciiifi. iwlr'm.,.. - P"",. 'l'rb-. I I Unctlflfnnity pm+p PIInI. IIICI'(hict.. AMln _ 18.. Inu::iII"Md.. ". PlV. tiidnm«... fial ililllbous bidder fauh..shwang SIIrlSB _ crush""" - f mwn.m and clip tji] J s; 0 f1oj/..p ;,,' 23 r.w I }=! -< R 22 c: 20;.,. ( I.sedifl'lllltBrylXlntBc1 :sadimjlbry b!lllx:ill FtiklIXIIS: +-i- --.noeli... ts/iomng P""'GO) +- ''''''''' Ish ng u'v'l 'f""," ---;r- minr upfld. with pllli'lg8 ---E-- minr dllvltlfnld. wi1h plljniii8 14 -IJ 1 Dip IIInd Slrib: 12 {.f<dfinci"_ :r - 10' ",..meal '",.. ttrrn.i, pho :!O f 126 ;11 r26.'u \80 _,Icldy.,"'" IN., dmxjd b by '26...", _, bunii<v. ind '27_ sa"" GfJ5Q6 J l O'i!'" 08 - IrIdc mv SlllltlM'! 07..! ''"" +,/ I NY'-minld i / 7./ Ia Jt A I... " f.. uu / / I Kilme'res % 1 Milts Map c- rdinallfls Iffl fr the thusand - melre grid 01 the 1 : lpovraphicl1 map slritls (NZMS 280) BUill map : jlrl'liinat I : sheets '260 and 7278 /:;?.i / I / $" / PIO 1.- Gelgical map r the area between Wharcama and Ngahape. Fr detailed gelgy f inset see Fig. 4. Crss-seclins A- A' nd 8-8 are shwn in Fig. 5 1 :;: bn!a:i. - cnglmerat! A ---taz ctcs:s- :llflctioil 16 '"nc: 2H j:l I '.. 1M en ("T1 i -- ""0 ::r:, I! ::..T--:-J ;;:t: '1,, ''''" " '1T{'- -II," :. 8a :: 6ll 59 58

5 MOORE - STRATIGRAPHY & STRUCTURE, E. WAIRARAPA 169 sandstne is mre cmmn m the upper (Piripauan) part f the frmatin, and siltstne with lensid cncretins, alternating sandstne and siltstne, and thinbedded sandstne (Fig. 2) in the lwer (Mangatanean Teratan) part. Cnglmerate appears t increase t the suth. Cnglmerates cntaining a high prprtin f redweathering pebbles are a distinctive feature f the frmatin. X-ray diffractin analysis indicates that the pebbles cnsist f siderite, rhdchrsite, and quartz (J. Olivecrna pers. cmm.). The mineral assemblage is identical t that f thin (1-5 cm) sideritic beds and cncretins fund, in particular, in thin-bedded sandstne and siltstne phases. Other features f the frmatin include intrafrmatinal slump znes, cyclic sequences (Fig. 3), and thin «1 em) cal seams. Sills f albite dlerite and livine dlerite, and thin dikes f basalt and dlerite, intrude the sedimentary sequence. 10m 5 F. (-s FIG. 3-Cyclic sequence in Glenburn Frmatin, Sea View Rad, T27/ Sequence cnsists f thick, light-grey fine t medium sandstne alternating with dark grey centimetre-bedded fine sandstne and thin (2-5 cm) sideritic bed(s). Sideritic beds generally ccur at the base f each dark sandstne interval. Light-grey sandstne beds shw parallel laminatin and rare current-ripple laminatin (mstly nly near the tp). F=fault. Sequence is verlain by 10 m f thin-bedded sandstne (beds generally 5-30 cm). Cnglmerates Beds f cnglmerate and breccia-cnglmerate are cha,racteristic f the frmatin. They range in thickness frm 5 cm up t 20 m, althugh mst are 1-3 m thick. Beds 8-10 m thick are nt unusual. Mst cnglmerates are prly bedded and prly srted, and cntain subt well-runded clasts ranging frm 1 cm t cm lng. Large angular blcks (sme> 1-2 m) f Glenburntype sandstne, and indurated sandstne prbably derived frm Pahaa Grup, ccur in sme beds. The smalle.r clasts are cmpsed predminantly f indurated fine sandstne, siderite, and cncretins. Subrdinate lithlgies include dark grey greywacke, siltstne, spilite, rhylite, and rare quartz and cnglmerate. Sme cnglmerates cntain pieces f petrified wd and rewrked belemnite guards. A significant prprtin f the indurated fine sandstne and sideritic pebbles are angular t subangular and were mst likely lcally derived. The sandstne appears t be largely derived frm Pahaa Grup, but sme culd als cme frm yunger Clarence rcks. Cnsiderable ersin f earlier frmatins, and/r rewrking f lder parts f Glenburn Frmatin, is indicated by the high percentage f sideritic pebbles and the ccurrence f bulders cntaining Megatrignia glyptica (Ngaterian-Arwhanan) in cnglmerates f Mangatanean-Teratan age. FOSJils and Age The mst cmmn fssils in the frmatin are Inceramus, which ccur in a range f lithlgies and include the key species (Wellman 1959) Inceramu.r bicl'rugatus Marwick, I. pe/ius, I. nukeus, I. pacificus, and I. australis Wellman. Inceramus australis ccurs in the uppermst part f the frmatin, apparently abve the highest I. pacificus. At ne lcality (T27/f26011) 1. australis ccurs with I. pacificus. Other fssils cllected, in place, include "Terebellina" (T26j9534), a spatangid echinid (T26/f9528, f9523), and a?gaudryceratid ammnid. The Ngaterian Arwhanan bivalve Megatrignia glyptica is knwn nly frm flat bulders, all f which are prbably rewrked frm cnglmerates in the upper part f the

6 170 N.z. JOURNAL OF GEOLOGY AND GEOPHYSICS, VOL. 23, 1980 frmatin. Cnglmerate beds als cntain Inceramus fragments and wrn guards f Dimetbelus sp. (T27/ f25). Fssil resin was cllected frm ne sandstne bed. The fssils indicate a Mangatanean-Piripauan age fr the frmatin. Thickne.rs Minimum thickness ranges frm abut 900 t 1000 m. TE MAl FORMATION (Late Piripauan-early Haumurian) Jhnstn (1975) intrduced the name Te Mai Frmatin fr a sequence f well-bedded, cmmnly crssbedded, alternating sandstne and siltstne with thick interbedded grit and carser cnglmerate crpping ut in the Tinui-Awatiti district. In the Whareama Ngahape area a unit f predminantly thin bedded sandstne and minr mudstne verlying the highly cnglmeratic Glenburn Frmatin is equated with Te Mai Frmatin. Apart frm having fewer thick sandstne beds the unit in the mapped area clsely resembles the type sectin. Thick cnglmerate beds, up t 1-2 m, are extremely rare, in cntrast t the underlying Glenburn Frmatin. The base f Te Mai Frmatin, therefre, is placed at the tp f the uppermst thick, carse cnglmerate in Glenburn Frmatin. Althugh the bundary is smewhat arbitrarily fixed in places, in the suthern part f the area it can be fixed reasnably well. In general, the' bundary mre-r-less cincides with the upper limit f thicker sandstne beds. Te Mai Frmatin cnsists predminantly f thinbedded (beds 2-5 cm), carbnaceus, fine t very fine andstne and thin interbedded dark grey mudstne. Sandstne beds are cmmnly graded and generally shw parallel and current ripple laminatin. Wavy bedding is widespread. Biturbatin, particularly f finer sediments, is ubiquitus, and beds als cntain a few marcasite ndules, calcareus cncretins, and bands f grit and breccia. Thicker sandstne beds are generally carser grained, cmmnly cnglmeratic r gritty at the base, parallel laminated, and in places shw channelling and lad casts A few glaucnitic sandstne dikes ccur in the uppermst part f the frmatin. In the upper,reaches f Mtuwaireka Stream a 20-mwide zne cnsisting f large angular blcks f sandstne (Glenburn Frmatin) up t 1 m acrss, cncretins, and well-runded sandstne pebbles in a sheared, gritty siltstne matrix, is interpreted as a slump breccia. Disturbed beds verlie the breccia. The breccia is als expsed n Rewa Ridge Rad where it cntains huge blcks (up t 10 m lng) f Pahaa Grup (?) sandstne assciated with mixed Mata lithlgies. Cntinuatin f the breccia t the nrth is indicated by the presence f bulders f indurated Pahaa Grup sandstne in the headwaters f Waihra Stream. Similar, but less extensive, breccia units are present in the suthern part f the area (e.g., in the upper reaches f Kpi Stream) (Fig. 4). Te Mai F-rmatin is interbedded with, and intruded by, a variety f igneus rcks (Ngahape Cmplex), including sills and dikes f basalt and dlerite, pillw la va, and breccia. Fssils and Age Fssils are rare in Te Mai Frmatin, and samples cllected fr micrfauna have mstly prved barren. Pllen and spres are sparse and generally nndiagnstic. "Terebellina" is abundant lcally (T27 / 32). In the nrthern part f the area, in branches f Waihra Stream, lcalities inferred t be clse t the base f the frmatin yielded Inceramus pacificus Wds, Ostrea lapillicla Marwick, and I. cf. mattrus. In the suthern part f the area Inceramus matlrus Wellman was cllected frm a breccia-cnglmerate near the middle f the frmatin (T27 /f34), and a large flat Inceramus (pssibly I. mattrus) frm near the base (T27/f26). Over the years a number f fssils, including ammnids, have been cllected frm lse bulders in streams. It is likely that mst, if nt all, f the calcarelus bulders are derived frm beds adjacent t pillw lavas (e.g., at T27/582088). Bulders in Ttara Stream have yielded a particularly gd fauna, including Thyasira sp. and a heterdnt bivalve (T26/f30), Trignia sp. (T26/f6880), and se,-eral ammnites (T26/f6981; listed in P. Wellman 1970). In Kpi Stream a blck f cncretinary sandstne cntained Scaphites sp. and abundant?lxnema sp. Other lse ammnites, including Pseudxybelceras n.sp., have been cllected further suth (T27/f6804, f6983, 33). All f the fssils supprt a Piripauan-Haumurian age fr the frmatin. Thickness Thickness ranges frm abut 200 m 111 the suthwest t ver 1000 m in the nrth. WHANGAI FORMATION (Late Haumurian-Teurian; Lillie 1953, after Quennel & Brwn 1937) Whangai Frmatin in the mapped area cnsists f hard, prly bedded, dark grey (light grey weathering) siltstne, with a few thin fine sandstne beds, particularly near the base. Glaucnitic sandstne dikes up t several metres thick, which are prbably largely derived frm thick glaucnitic sandstne lenses at r near the base (e.g., Fernglen Rad), ccur thrughut the frmatin. Siltstne in the upper part f the frmatin appears mre sandy, weathers a distinctly blue-grey clur n freshly expsed surfaces, and cntains sparse cncretins and infaunal bivalves. A yellw efflrescence (jarsite?) is develped n sheltered utcrps, particularly in the lwer parts f the unit. N angular discrdance between Whangai Frmatin and the underlying Te Mai Frmatin has been bserved, and at mst lcalities there is a gradatin frm sandstne t siltstne ver a I-2-m-thick zne. In the nrth, at Whareama Rad (T26/634I72) and' Kintail Rad (T26/590145), a thick biturbated sandstne unit cntaining numerus cncretins ccurs at the tp f Te Mai Frmatin. The cntact at the latter lcality is

7 MOORE- STRATIGRAPHY & STRUCTURE, E WAIRARAPA 06 t N I 500, I 1000m I pm+pl B 05 NGAHAPE aw "- C).. '6!:l' B' "> j Ngahape Vlcanic Cmplex Basalt sills. flws. dikes. and breccia G fl9 Fssil lcality ; Stage bundary Albite dlerite sills 66 6 Sedimentary breccia Breccia- cnglmerate FIG. 4- Detailed gelgy f the Ngahape area shwing fssillcalites and stage bundaries alng the imprtant Kaiwhata Stream sectin. Fr extended legend see Fig. 1

8 MOORE - STRATIGRAPHY & STRUCTURE, E. WAIRARAPA 171 marked by a 5-cm-thick lens f fine (basal) cnglmerate cnsisting f highly weathered igneus clasts. In the suth the cntact appears much sharper and is cmmnly verlain by a thin pebbly hrizn (e.g., Central Rad). In a branch f Kpi Stream (T27/ ) the cntact is well-expsed, and at the base f the Whangai siltstne is a cm, carse cnglmerate cnsisting f runded hard fin sandstne and angular t subangular cbbles f highly weathered vesiculalf lava up t 30 cm diameter. The cntact must be regarded, therefre, as lcally discnfrmable. In the Ngahape area, a band f pillw lava and breccia lies alng the cntact between the Whangai and Te Mai Frmatins, and further nrth, n Fernglen Rad (T27/574077), highly weathered lava ccurs within Whangai Frmatin. The latter ccurrence culd be a large slumped blck, but it seems likely, judging frm the presence f flat bulders in Makahaka Stream and a prly expsed utcrp near Ngahape Schl (Fig. 4), that igneus rcks intrude the frmatin. Fssils and Age Apart frm the spradic ccurrence f "T erebellina" tubes (e.g., T26/f8) and small bivalves, mainly Nucula sp. (e.g., T26/f18), fssils are extremely sparse. Single taxa cllected include Neil sp. (T26/f9535), an echinid spine, and?dentalium sp. (T26/f9536). Samples cllected fr micrfauna have mstly prved barren, but ne lcality (T26/f4), apprximately m abve the base, yielded framinifera which indicate a Haumurian age. In the Whareama area, micrfaunas frm tw lcalities clse t the base f the frmatin (T26/f7611, f7620) give Haumurian and Teurian ages respectively. One ther sample (T26/f8996), f uncertain lcatin, but prbably cllected frm Whareama Rad, als yielded Teurian framinifera. The age f Whangai Frmatin, therefre, ranges frm late Haumurian t Teurian, the base pssibly being diachrnus. Thickness Maximum thickness is prbably abut 500 m. WAIPAWA FORMATION (Teurian; Jhnstn 1975, after Finlay 1940) In the mapped area the frmatin cnsists f at least m f dark brwn t black sandy siltstne and fine sandstne with widespread glaucnitic sandstne laminae, beds and lenses, and scattered glaucnitic dikes. The unit is cmmnly very micaceus and intensely biturbated lcally. Large cncretins cntaining "T erebellina" ccur in an utcrp beside Whareama Rad. Much f the frmatin is strngly flded and faulted. The cntact with the underlying Whangai Frmatin is rarely well-expsed, but at several lcalities it appears gradatinal. In a branch f Kaiwhata Stream (T27/ ), fr example, thin-bedded brwn-grey siltstne and quartzse fine sandstne with glaucnitic sandstne lenses passes rapidly dwnwards int hard siltstne f Whangai Frmatin. The Waipawa sediments shw cnsiderable sft-sediment defrmatin, intense biturbatin, and yellw efflrescence n sheltered utcrps. A gradatinal cntact is als expsed in a rad cutting at T27/586053, and n Blairlgie Rad (T27/642234) where a cmplete transitin frm Whangai siltstne thrugh Waipawa Frmatin t Huatkitki siltstne and sandstne can be bserved. Fssils and Age Apat4t frm flattened tubes f "Terebellini", which are lcally abundant (e.g., T275f20), macrfssils are rare. In Kaiwhata Stream, glaucnitic sandstne at T27/ 20 cntains a shell bed f prly preserved bivalves. A bulder cllected further upstream cntaining "Wangalan" macrfssils (T27/f6728; Hrnibrk & Harringtn 1957) is mst likely derived frm the frmatin. Of numerus samples previusly cllected fr micrfauna and flra, mst have prved barren. Three lcalities, hwever, have yielded sparse framinifera indicating a Teurian age-t27/ 6989, T26/f27 (pssibly Dt), and T26/f7031. Minute calcareus species, including sme planktnics, were identified (N. de B. Hrnibrk pers cmm.) in a recllectin frm the latter lcality. Thickness Maximum thickness is difficult t estimate, but is prbably clse t 50 m. HUATOKITOKI FORMATION (Teurian-Waipawan) Van den Heuve1 (1960) intrduced the name Huatkitki Bentnite fr a sequence f bentnitic siltstnes and interbedded glaucnitic sandstne verlying Kaiwhata Limestne in the Flat Pint area. The frmatin was cnsidered t range frm Mangarapan t Brtnian, but Eade (1966) and Jhnstn (1975) have since included sediments f Waipawan age in the unit. In the Whareama-Ngahape area, nly the basal m f the frmatin is preserved. It cnsists predminantly f thin-bedded glaucnitic, micaceus fine sandstne with lenses and dikes f mre glaucnitic sandstne, and rare breccia. Sme beds cntain laminae f quartzse sandstne, and sideritic ndules. Althugh Jhnstn (1975) recgnised an uncnfrmity at the base f the frmatin in the Tinui area, n angular discrdance is evident in the Whareama-Ngahape area. Uplift nearby, hwever, is suggested by the ccurrence f slump structures, and f breccia cntaining large angular clasts f Waipawa siltstne and lithlgies frm lder units. In Kaiwhata Stream (T27/563039), fr example, large blcks f Waipawa-like sandstne ccur within flded beds, and an islated cbble f vesicular lava, prbably derived frm the Ngahape Cmplex, was fund in similar beds nearby at T27/ In Mtuwaireka Stream (T26/634108) a carse brecciacnglmerate cntains large blcks f Glenburn-type sandstne, cmmn clasts f grey-black sandy siltstne (Waipawa?), and pebbles f sandstne, greywacke, and igneus lithlgies. Fssils and Age Framinifera cllected frm the Kaiwhata Stream sectin (T27/f6991, f6985) indicate a TeUl'ian and yunger age fr the frmatin. Macrfssils are very rare, but at ne lcality (T27/f19) include Nucula sp. and ther small bivalves. 3'

9 A SECTION A-A' A' -J '"""' N 500 m Whareama Syncline m West West Kaiwhata / Sill (.il SECTION 8-8' 5 2km true scale I I I I I -500 '" / / / / / /. 41., /,/ /././ / / It. ", / / / / ::: East Nrth west Suth east 5 1 km true scale I I I N FIG. 5-Crss-sectins: sectin A-A' based n Fig. 1 and sectin B-B' n Fig. 4. Nte the difference in scale. Sequence east f Pukerr Fault yungs t the west.,:; 8' z N '-< c::: Z :» t"" "1 GJ trl t"" Q :» Z CI C'l trl "C n Y' r' 00

10 MOORE - STRATIGRAPHY & STRUCTURE, E. W AIRARAPA 173 The surce f the flat bulder cntaining Brtnian macrfssils (TZ7/f6733; P. Wellman 1970) is unknwn. Hwever, since n sediments f this age have been mapped in the area, it is inferred that a sliver f Brtnian sediments is preserved alng Pukerr Fault. In the mapped area the frmatin prbably ranges frm Teurian t Waipawan in age. Thickness In the Kaiwhata Stream sectin thickness IS abut 250 m. WHAKATAKI FORMATION (Altnian-Lillburnian; Jhnstn 1975) Alternating sandstne and siltstne and siltstne, with lenses f algal limestne, cnglmerate and breccia, crpping ut alng the eastern margin f the Late Cretaceus-Early Tertiary belt, is mapped as Whakataki Frmatin. Sft grey sandstne, siltstne, and minr cnglmerate suth f Ngahape are als tentatively included in the frmatin. The unit rests uncnfrmably n lder rcks. In the east, graded beds frm the dminant lithtype. The beds generally range frm 5-Z0 em thick and shw cmmn parallel, cnvlute, and crss-laminatin. Grit and brken shell material ccur at the base f sme thicker beds. Tw small lenses f extremely hard, dense algal limestne cntaining glaucnitic sandstne pebbles, Os/rea, and brachipds crp ut near the muth f Waihra Stream. Other minr lithlgies include pebbly siltstne, and cnglmerate and slump breccia (TZ7/ ). The sediments near Ngahape cntain pebbly beds with subrunded, weathered vesicular lava pebbles and cbbles up t 15 cm diameter, subangular fine sandstne, and blcks f Pahaa Grup lithlgies. The vlcanic pebbles were almst certainly derived frm the Ngahape Cmplex. Fssils and Age Whakataki sediments n the west limb f Whareama Syncline (Fig. 5) cntain scattered macrfssils, a few shellbeds, and a micrfauna indicating an Altnian t Lillburnian age (T26/f951l, TZ7/f7505). The age is the same as that f Takiritini Frmatin (Jhnstn 1975), and lateral equivalence is als supprted by the algal limestne lenses. The sediments near Ngahape are prbably entirely Altnian in age (P. Wellman 1970). Thickness In Whareama Syncline the frmatin is abut 1000 m thick. IGNEOUS ROCKS Igneus rcks in the Ngahape area have received a great deal f attentin since Crawfrd (1861) reprted the ccurrence f "trachytes" in Brcken Range. A brief accunt by Brwn (1943) was fllwed by a detailed petrlgical study f the Ngahape sills and Red Hill teschenite by Huttn (1943). Gardiner (1965) and Grapes (1970) have described the mineralgy and petrlgy f the Kaiwhata sills in sme detail. Pahaa Grup Igneus rcks and tuffaceus "red beds" in Pahaa Grup are described elsewhere (Mre & Speden in prep.). Tw ccurrences f interest, hwever, are Kpi Bninite, a quenched livine basalt cntaining lng, needle-like crystals f clinpyrxene (c. P. Wd pers. cmm.) and an 8-m-thick zned sill f spilite adjacent t Adams Fault. Kpi Bninite shws pillw structure in ne utcrp, indicating prbable extrusin directly n t the sea flr. Relatinships f the igneus rcks t thse f the Ngahape Vlcanic Cmplex are unknwn, but field bservatins elsewhere suggest that mst f the intrusins/extrusins within Pahaa Grup are cntempraneus with, r immediately pst-date, sedimentatin (i.e., mstly Mtuan). Grapes (1970) included these Early Cretaceus rcks in his "East Wairarapa Igneus Cmplex". Ngahape Vlcanic Cmplex (new) Althugh the sills and flws in the Ngahape area have been extensively studied, bth chemically and petrgraphically (Huttn 1943; Grapes 1970), they have nt previusly been mapped in detail. Frestry rads in the area have prvided better expsure, particularly in the upper reaches f Kaiwhata Stream, and a fuller descriptin f the igneus rcks can nw be presented. Basalt flws, pillw lava, vlcanic breccia, and dlerite sills and dikes within the Late Cretaceus-Early Tertiary sedimentary sequence (Glenburn-Whangai Frmatins) east f Adams Fault are here included in ne unit-the Ngahape Vlcanic Cmplex. In the mapped area extrusive rcks predminate. The Red Hill teschenite (Huttn 1943; Cles 1968; Simpsn 1969) is, based n its chemical and petrgraphic affinities with the Ngahape igneus rcks; designated a separate member (Red Hill Teschenite) f the cmplex. Further subdivisin f the igneus rcks near Ngahape is nt attempted at this stage. The cmplex is, in part, equivalent t the East Wairarapa Igneus Cmplex f Grapes (1970). Glenburn Frmatin is intruded by sills f albite dlerite, livine dlerite and spilite, and rare dikes f basalt (Figs 4, 5). The well-knwn "Kaiwhata sill" cnsists, cntrary t the pinin f thers (Brwn 1943; H. Wellman 1955; Grapes 1970), f tw distinctly separate sills f different cmpsitin (Fig. 4). These are named the East and West Kaiwhata Sills. The eastern sill, which bifurcates nrth f Kaiwhata Stream, is up t 40 m thick and cnsists f albite dlerite. The western sill, which can be fllwed discntinuusly fr several kilmetres t the nrth and suth f Kaiwhata Stream, cnsists f livine dlerite. Accrding t H. Wellman (1955) the western sill is verlain, in Kwhai Stream, by a cnglmerate cntaining basalt pebbles, but n definite vlcanic clasts were bserved by the writer.. Basalt flws, including pillw lava, "pillw breccia", and minr sills and dikes f basalt and dlerite, ccur in Te Mai Frmatin. The largest cmplex is in the 3"

11 174 N.Z. JOURNAL OF GEOLOGY AND GEOPHYSICS, VOL. 23, 1980 Ttara Stream area, where vlcanic piles, perhaps 50 m r mre thick, crp ut n the ridges nrth and suth f the stream. Other flws ccur west f Kpi Stream and adjacent t Adams Fault (Fig. 4). Pillw basalt (Fig. 6) and breccia frming a knll (knwn lcally as "Red Hill") at the end f Ttara Track cntains numerus vugs and veins f calcite and zelite minerals (Ansin 1970). Pillw basalt crpping ut in Ttara Stream yielded nickel values f up t 230 ppm, and a flat sample cllected dwnstream cntained 1'5% Ni (Amil n.d.). Age f Intrusin/Extrusin The East and West Kaiwhata Sills are carse grained and are inferred t have cled relatively slwly under a minimum f m f sediment. The stratigraphically higher vlcanic rcks are entirely basaltic and cnsist f pillw lava, pillw breccia, and fine-grained sills mst likely extruded directly n t the sea flr. A lens f basalt pebbles in Te Mai Frmatin, crpping ut clse t a pillw lava in Ttara Stream, indicates that sme lava was briefly expsed during sedimentatin. The highest well-defined vlcanic bands lie clse t the Te Mai-Whangai bundary, althugh an expsure f extremely weathered lava n Fernglen Rad (T27/ ), a prly expsed utcrp near the ld Ngahape Schl (Fig. 4), and flat bulders in Makahaka Stream, suggest that the igneus rcks als intrude Whangai Frmatin. If the sills and flws are assumed t be cntempraneus, vlcanic activity was restricted t Haumurian-Teurian (Maastrichtian-Palecene) time. ENVIRONMENT OF DEPOSITION The abundance f carse, prly srted cnglmerate and thick, parallel-laminated carbnaceus sandstne in Glenburn Frmatin implies a shallw-water, shelf r marine delta envirnment. Cnglmerates shw n clear imbricatin f pebbles, and many were prbably emplaced by mass flw. Indicatins f paleslpe are few, but evidence such as asymmetric, prbably intrafrmatinal, flds and small-scale step faults suggests a westerly inclined slpe. Such indicatrs, hwever, culd merely reflect lcal uplift within the basin. Cnglmerate appears t increase in abundance t the suth. Te Mai Frmatin is characterised by thin, cmmnly wavy, bedding and abundant ripple crss-laminatin. Current directins in bth the Te Mai and Glenburn Frmatins, based n ripple-laminatin, are predminantly t the nrth and suth. Wavy bedding, which tgether with lenticular and flaser bedding is cnsidered typical f tidal situatins (Reineck & Singh 1973), and indicatins f ppsing currents, suggests that Te Mai Frmatin culd have been depsited in a narrw, tidal strait. The presence f interbedded highly vesicular pillw lava als favurs shallw-water cnditins. There is n clear indicatin f the envirnment f depsitin f Whangai Frmatin, althugh the cmmn glaucnite perhaps favurs shelf cnditins. Relatively shallw-water depsitin is suggested by the nature f immediately underlying and verlying sediments. The fine grain size f the frmatin indicates restricted supply f carse detritus, due t a much-reduced landmass and/r islatin f the basin f depsitin (see als Lillie 1953, p. 78). The highly carbnaceus and glaucnitic nature f Waipawa Frmatin, tgether with a very sparse macrfauna, suggests depsitin in a very restricted basin, perhaps clse inshre. Framinifera suggest very shallw water cnditins (N. de B. Hrnibrk pers. cmm.). The verlying Huatkitki sandstne is similarly highly glaucnitic and sparsely fssiliferus, but was prbably depsited in mre pen shelf cnditins. FIG. 6-Outcrp f pillw lava at the end f Ttara Track, T27/584085_ Lava frms part f a large vlcanic pile withitl Te Mai Frmatin. Pillws have prminent cherty selvedges and face twards the tp right f pht.

12 MOORE - STRATIGRAPHY & STRUCTURE, E. WAIRARAPA 175 The flysch-like Whakataki Frmatin was mst likely depsited in a mderately deep basin (bathyl, based n framinifera), with algal mats being frmed clse t the basin margins, r n lcal shallws prduced by flding (Jhnstn 1975). STRUCTURE As in mst parts f eastern Wairarapa, the area between Whareama and Ngahape is dminated by NNE-trending structures (Fig. 1). The nrthern half is essentially a large anticline with tight flanking synclines, and the suthern half a faulted, west-dipping sectin. Flds Majr flds in the area generally trend NNE, althugh sme swing t the nrth-east and east, particularly in the vicinity f Kaumingi Fault. Fld axes appear t be mstly subhrizntal, but tw anticlines t the nrth and suth f Kaumingi Fault have slight plunges away frm the fault. In the west, suth f Kaumingi Stream, the sequence is flded int a tight syncline (Fig. 5), with the fld axis being truncated in places by Adams Fault. The nrthern end f the syncline is reflded abut a subvertical axis, and east f Kpi Stream the eastern limb is lcally verturned (Figs. 1, 4). Small-scale (messcpic) flds are relatively cmmn, particularly in Glenburn Frmatin. Many are asymmetric and are interpreted as intrafrmatinal slump structures, but flds in a fault-bunded blck between the Mtuwaireka and Mangapiuiti Streams are prbably tectnic. These flds increase in number, and amunt f plunge, twards the suth. An east-west-striking syncline further west, in Mangapiuiti Stream, ccurs within a separate fault-bunded blck. Cntrasting fld trends suggest that flding prbably ccurred in respnse t lcal fault mvements. Small, mstly asymmetric flds at the base f Whangai Frmatin alng Strm Ridge Rad plunge t the west at , the same as the eastern limb f the syncline. These flds, therefre, are prbably synchrnus with r predate the majr fld. Faults Fur majr faults transect the area, three f them NNE trending, and ne-kaumingi Fault-ENE trending. The latter fault has nt previusly been recgnised. Adams Fault is a very majr fracture, extending frm Pahaa, 30 km t the suth-west (Eade 1966), as far nrth as the Mangapakeha valley (Jhnstn 1975). (Jhnstn named the nrthern sectin Tinui Fault, but the name "Adams" has precedence.) At the nly pint (T26/588146), where the fault is clearly expsed, there is a crush zne cm wide dipping 80 east. Relatinships t tpgraphy als suggest the fault is near-vertical. In cntrast, Pukerr Fault appears t be a lw-angle reverse fault. Intersectins with tpgraphy suggest that between the Kaiwhata and Kwhai Streams the fault dips between 20 and 40 0 west (Fig. 4). If the pst Whakataki anticlinal axis lies t the east, then restratin f the pre-whakataki ersin surface t hrizntal (by unflding) wuld indicate that the fault had an even shallwer dip riginally. Mtuwaireka Fault (new name) was previusly mapped as an extensin f Tutu Fault by P. Wellman (1970, fig. 4), wh inferred a sinistral strike slip mvement f 50 km frm thickness changes in Kaiwhata limestne (Teurian) acrss the fault. The name Tutu Fault, hwever, is best restricted t that part suth f Kaiwhata River, where the limestne is juxtapsed against lder rcks. There is n evidence fr transcurrent mvement alng Mtuwaireka Fault, and the limestne facies is absent in the Whareama-Ngahape area. The ENE-trending Kaumingi Fault is the nly ne shwing definite evidence f strike-slip mvement, and it is subparallel t, and has the same sense f displacement as, the active Cartertn Fault (Lensen 1968; Jhnstn 1975). Restratin f the ffset Adams Fault t its riginal psitin reveals a cnsiderable difference in the structures nrth and suth f Kaumingi Fault, suggesting that there is als a substantial vertical cmpnent. Alternatively the flds may pst-date the faulting, as discussed later. There is n evidence fr recent mvement n any f the majr faults, althugh Jhnstn (1975) mapped an active trace alng the nrthern prtin f Adams Fault. Timing f Fault Mvements Adams Fault ffsets bth Late Cretaceus and Late Tertiary (Altnian) strata, and has a vertical displacement well in excess f 1000 m. Te Mai Frmatin sandstne adjacent t the fault at T26/ shws penecntempraneus faulting, and is interbedded with sedimentary breccia cnsisting largely f Mata lithlgies. The fault, therefre, was- almst certainly active during depsitin f Te Mai Frmatin. Fault mvement during the Late Cretaceus is als suggested by a carse breccia, cntaining large blcks f Pahaa Grup sandstne, in Te Mai Frmatin further east. Altnian sediments near Ngahape are cut by the fault, but further suth Lillburnian-Tngaprutuan sediments verlie the fault (van den Heuvel 1960; Eade 1966). Lcal vertical mvement, therefre, als tk place during the Clifdenian. In the nrthern part f the mapped area Adams Fault is ffset by Kaumingi Fault, which itself is verlain by Altnian sediments. Since Adams Fault truncates Whangai Frmatin, lateral displacement alng Kaumingi Fault must have taken place between late Teurian and Altnian. Strike-slip mvement alng Kaumingi Fault sn after majr displacement n Adams Fault is suggested by several lines f evidence. Bishp (1968) has shwn that there is a cnsistent gemetric relatinship f certain structural features with strike-slip faults. Fld akes mapped in the vicinity f Kaumingi Fault are cnsistent with trends illustrated by Bishp (1968, fig. 4), and the yungest sediments in the cre f the flds are

13 176 N.Z. JOURNAL OF GEOLOGY AND GEOPHYSICS, VOL. 23, 1980 Teurian in age, which suggests that flding cmmenced sn after depsitin f Waipawa Frmatin (unless stripping f yunger strata is invked). Fld trends d nt match acrss the fault when the ffset Adams Fault is restred t its riginal psitin, indicating that the flds are either synchrnus with r pst-date the faulting. Field relatinships suggest that glaucnitic sandstne dikes in Whangai siltstne adjacent t the fault were intruded while the enclsing sediments were stijl relatively sft, but cmpact enugh t supprt pen fractures. Additinal evidence that culd indicate immediately pst-whangai, r even cntempraneus, mvement n Kaumingi Fault is the ccurrence f pssible slump flds at the base f Whangai Frmatin alng Strm Ridge Rad, and slump structures at the head f Hays Creek (T26/ ). The yungest beds preserved alng the Pukerr and Mtuwaireka Faults are Teurian in age, mstly Waipawa Frmatin. Evidence f cnsiderable instability is present in Huatkitki Frmatin, adjacent t Pukerr Fault, and the fact that yunger Dannevirke and Arnld Series sediments are absent suggests that faulting prbably ccurred in mid t late Dannevirke time (althugh sme Brtnian sediments culd be preserved alng Pukerr Fault). A lng perid f nn-depsitin, r ersin f yunger sediments t leave nly the Waipawa and part f Huatkitki Frmatin intact, seems unlikely. TECTONIC HISTORY 1. Adams Fault was prbably initiated during a majr, reginal intra-mtuan tectnic event, when Pahaa Grup sediments suffered widespread sft-sediment defrmatin (Mre & Speden 1979). 2. Evidence f tectnic activity during depsitin f Glenburn Frmatin is prvided by the intrafrmatinal flds and the abundance f lcally derived clasts in cnglmerates and breccias. Uplift and ersin f earlier depsited parts f the frmatin, and f lder frmatins, cntinued frm Mangatanean t Piripauan time (mid t late Cretaceus). 3. Adams Fault was almst certainly active during depsitin f Te Mai Frmatin. The extrusin f basaltic lava and intrusin f dlerite sills (Ngahape Cmplex) began abut the same time (Haumurian). 4. Igneus activity ceased shrtly after depsitin f Whangai Frmatin began, but lcal fault mvements prbably cntinued. Kaumingi Fault was mst likely initiated at this time. During the late Cretaceus and very early Tertiary (Haumurian-Teurian) the adjacent landmass was much reduced and/r mre distant. 5. Relatively stable cnditins persisted int early Teurian, but lcal fault mvements increased in intensity in latest Teurian time. Majr flding and faulting began shrtly after depsitin f Waipawa Frmatin and cntinued, perhaps, until Brtnian (Arnld Series; mid Ecene). Strike-slip (Kaumingi Fault) and reverse (Pukerr Fault) fault mvement tk place during this perid, prbably in the mid t late Dannevirke (early Ecene). 6. There is n recrd f Ecene t Oligcene sedimentatin, r f late Ecene t very early Micene tectnic activity. Depsitin began again in the early Micene (Altnian Stage; Suthland Series) in a rapidly subsiding basin. 7/Lcal mvement ccurred n Adams Fault in the Clifdenian (mid Micene). Further mvement prbably tk place in the Plicene, when the area was uplifted and Micene sediments flded int majr syncline and anticline. ACKNOWLEDGMENTS The assistance f Mr J. Rhdes, Central Institute f Technlgy, and Drs C. P. Strng, I. Raine, and I. G. Speden, N.Z. Gelgical Survey during fieldwrk (undertaken between February 1975 and May 1976) is greatly appreciated. I als wish t thank: Messrs B. Haggett and R. Turner, N.Z. Frest Service, fr their assistance, particularly in prviding maps f the area, and arranging accmmdatin; Drs I. G. Speden, P. A. Maxwell, and G. R. Stevens fr examining macrfssil cllectins; Drs C. P. Strng, N. de B. Hrnibrk, and 1. Raine fr examining samples fr micrfssils; and Mr J. Olivecrna fr XRD determinatins. I especially wish t thank Dr C. P. Wd fr his wrk n the igneus rcks. I am particularly grateful t the fllwing lcal peple fr prviding accmmdatin, and fr their hspitality: Mr and Mrs F. 1. Skeet "Khekhe", Mr and Mrs Lamb "Puketiritiri", Mr and Mrs V. W. Carrll "Karri" and Mr C. T. C. Hlmes. The paper benefited cnsiderably frm criticism by Drs M. R. Jhnstn and M. G. Laird, N.z. Gelgical Survey. Typing was undertaken by Mrs M. Feitsma. REFERENCES AMOIL N.z. LTD. (n.d.): Reprt f field wrk cmpleted in the Ngahape district. (Unpublished reprt 273, n pen file, N.z. Gelgical Survey.) ANSON, R : Recent mineral discveries. New Zealand Lapidary 3 (3): BISHOP, D. G. 1968: The gemetric relatinship f structural features assciated with majr strike-slip faults in New Zealand. N.Z. Jurnal f Gelgy and Gephysics 11: BROWN, D. A. 1943: The gelgy f the Brcken Range and the Kaiwhata Valley, East Wellingtn. Transactins f the Ryal Sciety f New Zealand 72: COLES, 1. G. 1968: Magnetic study f the Red HiJl igneus bdy, East Wairarapa. (Unpublished B.Sc.(Hns.) thesis, ldged in the library, Victria University. f Wellingtn.) CRAWFORD, J. C. 1861: Reprt n a gelgical tur in the Wairarapa and East Cast cuntry. New Zealand Gvemment Gazette (Prvince f Wellingtn) 8 (35): EADE, J. V. 1966: Stratigraphy and structure f the Munt Adams area, eastern Wairarapa. Transactins f the Ryal Sciety f New Zealand Gelgy 4:

14 MOORE - STRATIGRAPHY & STRUCTURE, E. WAIRARAPA 177 FINLAY, H. ]. 1940: New Zealand framinifera: key species in stratigraphy 4. Transactins f the Ryal Sciety f New Zealand 69: GARDINER, R. T. 1965: A nte n tw teschenite sills at Ngahape, eastern Wellingtn. (Unpublished B.Sc.(Hns.) thesis, ldged in the library, Victria University f Wellingtn.) GRAPES, R. H. 1970: A petrlgical study f the Kaiwhata Sill, Ngahape, east Wairarapa, New Zealand. Transactins f the Ryal Sciety f New Zealand Earth Sciences 7: VAN DEN HEUVEL, H. B. 1960: The gelgy f the Flat Pint area, eastern Wairarapa. N.z. Jurnal f Gelgy and Gephysics 3: HORNIBROOK, N. DE B.; HARRINGTON, H. J. 1957: The status f the Wangalan Stage. N.z. Jurnal f Science and Technlgy 38B: HUTTON, C. O. 1943: The igneus rcks f the Brcken Range-Ngahape area, east Wellingtn. Transactins f the Ryal Sciety f New Zealand 72: JOHNSTON, M. R. 1975: Sheet N159 and part N158 Tinui-Awatiti (1st ed.) "Gelgical Map f New Zealand 1 :63 360". Department f Scientific and Industrial Research, Wellingtn. --- (in press): Gelgy f the Tinui-Awatiti district. N.z. Gelgical Survey Bulletin 94. KATZ, H. R. 1976: Sedimentary basins and petrleum prspects, nshre and ffshre New Zealand. In "Circum-Pacific. Energy and Mineral Resurcs". American Assciatin f Petrleum Gelgists Memir 25: LENSEN, G. J. 1968: Sheet N158 Mastertn (1st ed.) "Late Quaternary Tectnic Map f New Zealand 1 :63 360". Department f Scientific and Industrial Research, Wellingtn. LILLIE, A. R. 1953: The gelgy f the Dannevirke Subdivisin. N.Z. Gelgical Survey Bulletin 46. MOORE, P. R.; SPEDEN, 1. G. 1979: Stratigraphy, structure, and inferred envirnments f depsitin f the Early Cretaceus sequence, Wairarapa, New Zealand. N.Z. Jurnal f Gelgy and Gephysics 22 (4): (in prep.): A revisin f the Early Cretaceus sequence in Wairarapa. N.z. Gelgical Survey Bulletin. QUENNELL, A. M.; BROWN, D. A. 1937: Dannevirke Subdivisin. N.Z. Gelgical Survey 31st Annual Reprt: 1-6. REINECK, H. E.; SINGH, 1. B. 1973: "Depsitinal Sedimentary Envirnments, with Reference t Terrigenus Clastics" Springer-Verlag Berlin. 429 p. SIMPSON, P. G. 1969: A petrlgical study f the Red Hill teschenite intrusin, east Wairarapa. (Unpublished B.Sc.(Hns.) thesis, ldged in the library, Victria University f Wellingtn.) WELLMAN, H. W. 1955: Gelgy f Ngahape district. (Unpublished reprt, N.Z. Gelgical Survey files.) : Divisins f the New Zealand Cretaceus. Transactins f the Ryal Sciety f New Zealand 87 (J and 2): WELLMAN, P. 1970: Gelgy f the Ngahape area, eastern Wairarapa. Transactins f the Ryal Sciety f New Zealand Earth Sciences 8: