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Marine Mollusca of oxygen isotope stages of the last 2 million years in New Zealand. Part 2. Biostratigraphically useful and new Pliocene to recent bivalves A. G. Beua a GNS Science, Lower Hutt, New Zealand Online publication date: 30 March 2010

To cite this Article Beu, A. G.(2006) 'Marine Mollusca of oxygen isotope stages of the last 2 million years in New Zealand.

Part 2. Biostratigraphically useful and new Pliocene to recent bivalves', Journal of the Royal Society of New Zealand, 36: 4, 151 — 338 To link to this Article: DOI: 10.1080/03014223.2006.9517808 URL: http://dx.doi.org/10.1080/03014223.2006.9517808

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151 Journal of the Royal Society of New Zealand Volume 36, Number 4, December, 2006, pp 151-338

Marine Mollusca of oxygen isotope stages of the last 2 million years in New Zealand. Part 2. Biostratigraphically useful and new Pliocene to Recent bivalves

Downloaded By: [Gns Science] At: 23:12 16 January 2011

A. G. Beu1

Abstract New Zealand Plio-Pleistocene bivalves revised: Limopsis, oysters, Pecten, Mactra (Maorimactra), Oxyperas, Lutraria, Austrovenus, Barnea, Myadora. Recent Indo-West Pacific Lutraria species are reviewed; the Red Sea-East African species L. (Lutraria) turneri Jousseaume resembles L. grandis (Hutton) (adopted in place of the junior homonym L. solida Hutton). Six new species proposed: Saccella maxwelli (Nukumaruan-Recent; known previously as S. bellula (A. Adams)); Limopsis turnbulli (Castlecliffian, OIS 15-20, SW Fiordland); Mactra (Maorimactra) marwicki (late Nukumaruan); M. (Maorimactra) carteri (early Castlecliffian, OIS 45?-19); Paphies delta (early Castlecliffian, OIS 31?-17); Myadora fortecosta (Kapitean-Opoitian). Further Indo-West Pacific warm-water migrants to New Zealand: Chama ruderalis Lamarck (Kapitean-Nukumaruan; = C. huttoni Hector, = C. pittensis Marwick); Lutraria (Psammophila) vellai (Beu) (late Nukumaruan); probably the two New Zealand late Neogene Ctenoides species. Further temperate migrant from the Atlantic: Lutraria (Lutraria) grandis. New synonymy: Xenostrobus Wilson = Limnoperna Rochebrune; Pecten novaezelandiae (Reeve) = all other New Zealand Pecten names; Serratina eugonia (Suter) = S. charlottae (E. A. Smith); Oxyperas komakoensis (Carter) = O. elongata (Quoy & Gaimard); Austrovenus stutchburyi (Wood) varies clinally over New Zealand, = A. aucklandica Powell, = A. crassitesta Finlay; Dosinia (Austrodosinia) horrida Marwick = D. anus (Philippi) (Nukumaruan-Recent); Panopea wanganuica Powell = P. smithae Powell (Nukumaruan-Recent); Myadora stephaniae Carter = M. waitotarana Powell (Waipipian-Nukumaruan). Distinctive bivalves extinct at the end of Nukumaruan time: Glycymeris shrimptoni Marwick, Patro undatus (Hutton), Lutraria (Lutraria) grandis, L. (Psammophila) vellai, Paphies crassiformis (Marshall & Murdoch), Eumarcia plana Marwick, Dosinia (Raina) nukumaruensis Marwick, Myadora waitotarana. Ennucula Iredale is used for Cenozoic and Recent Nuculominae; the application of Leionucula Quenstedt is unclear. Saccostrea glomerata (Gould) is used in place of S. circumsuta (Gould). Protothaca crassicosta (Deshayes) (formerly Haweran-Recent) is recorded from Opoitian rocks. Pecten novaezelandiae appeared below Potaka Tephra (1.0 Ma) during OIS 29 or earlier in eastern New Zealand, but just above the Brunhes-Matuyama transition (0.78 Ma, early OIS 19) in Wanganui Basin. Oxyperas elongata and Barnea similis (Gray) changed anagenetically through late Miocene-Pleistocene time; earlier forms are conspecific with Recent ones. Tawera Marwick is restored as a genus. Purpurocardia Maxwell is compared with Glans Megerle von Muhlfeld and Glyptoactis Stewart, and all are retained. Limnoperna huttoni (Suter) became extinct during OIS 13, Barytellina crassidens Marwick during OIS 9 or younger. Pholadidea tridens (Gray) (OIS 23 & 5a) and Ostreola virescens (Angas, 1868) are recorded fossil. 1

GNS Science, PO Box 30368, Lower Hutt 5040, New Zealand. [email protected] R06008 Received 23 June 2006; accepted 31 October 2006; Online publication date 14 November 2006

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Journal of the Royal Society of New Zealand, Volume 36, 2006


Keywords biostratigraphy; Bivalvia; Castlecliffian; dispersal; evolution; Haweran; Holocene; Mollusca; new species; New Zealand; Nukumaruan; oxygen isotope stages; Pleistocene; Pliocene; taxonomy; time scale; Wanganui Basin

INTRODUCTION This paper is the second part of a revision of the taxonomy and biostratigraphy of New Zealand fossil Mollusca of the last 2 million years, based largely on fossils recorded in the seminal work on Wanganui Basin by Charles Fleming (1947, 1953, 1957). The first part (Beu 2004) reconsidered the generic positions or species identifications of some New Zealand late Neogene to Recent molluscs. This included most of the recognised migrants from eastern Australia and the tropical Pacific that appeared briefly in New Zealand during interglacial periods, and one cool-water migrant from the northeastern Atlantic. The present report is based on a catalogue of all the Mollusca recorded as occurring in New Zealand within the last 2 million years, with detailed time ranges recorded in oxygen isotope stages (OIS). The catalogue was compiled initially from the detailed faunal lists provided for the formations of Wanganui Basin by Fleming (1953), assigned to individual oxygen isotope stages from correlation diagrams of cycles in Wanganui Basin with oxygen isotope stages (Naish et al. 1998; Carter & Naish 1999). The catalogue has been amplified extensively by my own collecting, and by collecting by my colleagues (listed in the Acknowledgments) who have determined the sequence stratigraphy, magnetic polarity stratigraphy, and tephrostratigraphy of Wanganui Basin (see particularly Naish 2005). Amplification of the earlier ranges of several taxa in Matemateaonga Formation (Tongaporutuan-Opoitian) in Wanganui Basin has also been provided by Austin Hendy (University of Cincinnati pers. comm.) based on his unpublished thesis research. This locality data is particularly valuable because the stratigraphy is mapped in 41 000-year sequences, allowing fossil localities to be dated unusually precisely. A few taxa included in the present paper (Chama ruderalis Lamarck, 1819, Lutraria vellai (Beu, 1966), Ctenoides species) are further warm-water migrants recognised since the previous paper was written, and Lutraria grandis (Hutton, 1873) is a further temperate-water migrant from the Atlantic via South Africa. The ranges and biostratigraphy recorded here are as much concerned with debunking apparent biostratigraphic guide species accepted in the past, but actually based on inaccurate time ranges or taxonomy, or on unreliable, strongly facies-controlled taxa, as they are on establishing new, reliable biostratigraphic criteria. The same topics will be covered for Gastropoda in the following part of this series, and for chitons (Polyplacophora) in the fourth part. The faunas included in this overview, their ages, and their oxygen isotope stage correlations were summarised by Beu (2004), and are not repeated here. Correlations and ages adopted by Beu (2004) have been confirmed and, in some cases, amplified by Proust & Chanier (2004; Cape Kidnappers section, Hawke's Bay) and, more importantly, in the major overview of Wanganui Basin tephrostratigraphy by Pillans et al. (2005). These slightly revised ages and OIS correlations have been adopted throughout. The correlation of Nukumaruan strata in Wanganui Basin suggested by Beu (2004) also has been completely revised, based on a new sequence stratigraphic interpretation (Abbott et al. 2005). A detailed survey of the small molluscs (under 10 mm, and particularly those under 5 mm in maximum dimension) in the Wanganui Basin succession obviously is desirable in the future for a full knowledge of both the fauna and the environmental changes demonstrated by the Mollusca of these beds. However, it would need to be based on the systematic collection of many large bulk samples from the entire section, in the way that Foraminifera have been studied systematically throughout New Zealand over the last 70 years, and is far beyond the scope of the present project. This type of research was begun by Laws (1940) on the Mangapani Shellbed and the Nukumaru Beach succession, and was carried on by Fleming (1953) on the more obvious shellbeds in the Castlecliff section. The previously unpublished drawings of

Beu—Pleistocene-late Pliocene bivalves

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many small molluscs from Wanganui (McEwen 2005b, end-papers) demonstrate that Fleming intended to publish a taxonomic treatment, sadly never completed, of the new taxa listed by Fleming (1953), along the lines of his paper on small Fiordland molluscs (Fleming 1948). However, a systematic examination is still needed of bulk samples for the Castlecliffian part of the section, in particular. Cooper et al. (2006) showed that small molluscs are not present in many collections because of collection bias, dissolution, or strong facies control in many faunas. In the best-preserved New Zealand Cenozoic molluscan faunas, only 43% of the total preservable fauna is retained, because of the combined small body size loss (36% of the fauna) and non-size-related loss (21 %), but the loss of small taxa can be reduced by nearly half through exhaustive collection and preparation. The rich Wanganui shellbed faunas therefore deserve attention. Fleming's (1953) survey of small molluscs in most of the Wanganui succession demonstrated that these taxa are highly diverse, well preserved, and easily extracted from mid-Pliocene to Pleistocene shellbeds, and this remains an enormous field of research for the future. In a little-known paper, Powell ( 1940) recommended using data from present-day ecology to improve rigour in paleoecology. He described the determination of grain-size by sieving, listed some of the common molluscs in his Recent Auckland and Manukau Harbour samples (Powell 1937a) limited to particular grain-sizes, and commented on their relevance for the study of "local fossil faunules" (Powell 1940, p. 610) (that is, those at Wanganui). He pointed out (Powell 1940, p. 610) that "…. many faunal changes consistent with oscillation in depth are indicated by animal communities identical with Recent ones that occur in the Upper Pliocene (Castlecliffian) of Wanganui…much useful data concerning the conditions of deposition can be worked out by analogy with Recent conditions…. Best results are obtained by reconstructing the fossil animal communities rather than by placing too much importance on evidence afforded by a few individual species". This anticipates the interpretation of Wanganui Basin fossil molluscan communities by Abbott & Carter (1997), Hendy & Kamp (2004), and Abbott et al. (2005). It is, therefore, of interest for the history of the study that Powell (1940, pl. 8-10) went on to illustrate the taxa present in four Auckland and Manukau Harbour Recent communities (from Powell 1937a), as well as those in five fossil communities at Wanganui. The five at Wanganui are (1) "deep-water open sea (unnamed community)" (Powell 1940, pl. 9, fig. 1), with Limaria orientalis (A. Adams & Reeve, 1850), Coluzea, Iredalula, and common small Turridae (sensu lato), probably collected from Pinnacle Sand, that is, deposited in no more than c. 30-50 m of water; (2) Tawera + [Tucetona laticostata (Quoy & Gaimard, 1835)] community (Powell 1940, pl. 9, fig. 2), with Purpurocardia and several specimens of Murexsul octogonus (Quoy & Gaimard, 1833), so collected from the basal shellbed of Shakespeare Cliff Sand, the only horizon where M. octogonus consistently can be collected at Wanganui; (3) [Fellaster] community (Powell 1940, pl. 9, fig. 3), dominated by Zethalia, Amalda, Paphies donacina (Spengler, 1793), and My adora striata (Quoy & Gaimard, 1835), with Austrovenus stutchburyi (Wood, 1828), so collected from the main unit of Shakespeare Cliff Sand; (4) "unnamed association of Echinocardium" community (Powell 1940, pl. 9, fig. 4), dominated by thin-shelled specimens of Neilo, Talochlamys gemmulata (Reeve, 1853), Pratulum, Stiracolpus, Pelicaria, and Poirieria, so probably collected from Omapu Shellbed; and (5) [Fellaster] community "typical of Nukumaru" (Powell 1940, pl. 10), dominated by Fellaster, Zethalia, Lutraria grandis, and Alicthoe, collected from Nukumaru Brown Sand. This paper has not been mentioned in any recent descriptions of Wanganui stratigraphy, but shows clearly how dependent Fleming (1953) was on Powell's (1937a) description of Auckland communities in his interpretation of Wanganui paleoecology, and that even the concept of "oscillations in depth" (Powell 1940, p. 610) at Wanganui was familiar before Fleming began his research. The foundation of Fleming's (1953) brilliant research was his grounding

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in Baden Powell's boys' club for shell collectors, illustrating the long succession of personal relationships in molluscan taxonomy and paleontology in New Zealand. As noted below under My adora kaiiwiensis Powell, 1931, "Master" C. A. Fleming, aged 14, accompanied A. W. B. Powell on his collecting trip to Wanganui during January 1931 (Powell 1931, p. 85; McEwen 2005b, p. 11, photo p. 31) which, along with Fleming's trip to the Chatham Islands with Powell during February 1933 (Powell 1933, p. 182; McEwen 2005b, p. 13), inspired Fleming's interest in Wanganui, and a lifetime of research on New Zealand natural history (Charles Fleming pers. comm.; see also McEwen [Charles' daughter] 2005a,b). Correlation of Pinnacle Sand The one minor change from the correlations of Castlecliffian formations in Wanganui Basin adopted by Beu (2004) is based on the record, below, of Limnoperna huttoni (Suter, 1914) from an estuarine bed immediately underlying Tainui Shellbed on the western side of the Whangaehu-Turakina interfluve, east of Wanganui. An estuarine bed immediately underlyng Tainui Shellbed is significant for sequence stratigraphy, as it implies that the estuarine bed is a Type A shellbed (of Abbott & Carter 1994; a transgressive systems tract, TST) at the base of a cycle, equivalent to the uppermost Pinnacle Sand in the area near the Castlecliff coast, overlain by Tainui Shellbed, the Type B shellbed of oxygen isotope stage (OIS) 13 (condensed section of a high-stand systems tract, HST). This interpretation supports the correlation of Pinnacle Sand with OIS 15, and of the estuarine bed with early OIS 13. A sequence boundary is assumed to underlie the estuarine bed, an interpretation made likely by Woolfe's (1987, p. 26) description of the contact: "The lower contact is a marked disconformity on the locally cross-bedded Pinnacle Sand. The contact is a sharp planar feature which clearly truncates underlying cross-stratified Pinnacle Sand". The estuarine bed is therefore referred to OIS 13. This supports the interpretation by T. R. Naish (GNS pers. comm.; Naish et al. 2005) that, in the Castlecliff coastal section, Pinnacle Sand is the uppermost, regressional unit deposited during OIS 15 and in part early in glacial OIS 14, rather than the lowest deposit of OIS 13, as adopted in the first of this series of papers, following Carter & Naish (1999) and all other previously published Wanganui Basin correlation diagrams. Pinnacle Sand is referred here to OIS 15/14. The resulting interpretation of the Pinnacle Sand-Tainui Shellbed contact in the Castlecliff coastal section as a sequence boundary that did not become exposed subaerially (and therefore need not have the usual Type A TST shellbed overlying it, as it does a little further inland on the present Whangaehu-Turakina interfluve, where it was evidently exposed subaerially) has two further implications. Firstly, the North Atlantic-Mediterranean cool-water mussel Modiolula phaseolina (Philippi, 1844) is recorded in New Zealand only from the uppermost 0.6 m of Pinnacle Sand at "the pinnacles" gully, Castlecliff (Beu 2004, p. 144). The possible interpretation of upper Pinnacle Sand as a regressive systems tract, deposited early in OIS 14, overlying the interglacial deposits of OIS 15, would mean that this cool-water migrant occurred in New Zealand during the early part of a glacial period. It is more likely that such an Atlantic coolwater species would have been transported here via South Africa as planktonic larvae in the Antarctic Circumpolar Current during glacial OIS 14 than during a warm interglacial period. This lends support to the correlation. It further suggests the possibility that other cool-water migrants could have appeared in New Zealand during glacial periods, but are not recorded in the punctuated succession in Wanganui Basin, where apparently no other glacial periods are represented by rock in the late Castlecliffian part of the succession. Secondly, the distinction between the Pecten marwicki (Finlay, 1930) and P. tainui (Finlay, 1930) forms of P. novaezelandiae Reeve, 1852 is interpreted below as entirely ecophenotypic. It occurred at a sharp ecotone, preserved in the Wanganui Basin succession only as


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the intermediate specimens identified by Fleming (1957, p. 39) as "Pecten jacobeaus toi” Fleming, 1951 (see below). These intermediate specimens occur only in the uppermost 1 m or so of Pinnacle Sand, that is, only in the deposits correlated with OIS 14. The preservation of specimens intermediate between the two extreme Pecten forms at only this horizon lends further support to the correlation of this horizon with part of the glacial-interglacial cycle otherwise virtually unknown in the Castlecliffian rocks of Wanganui Basin, such as a marine regressive systems tract (RST), deposited early in a glacial period. It also allows the possible interpretation of the intermediate specimens as living well to the south (perhaps hundreds of kilometres to the south) of the commonly preserved extreme phenotypes during interglacial periods, and only appearing in Wanganui Basin when temperatures fell and faunas migrated northwards. Unfortunately, appropriate late Castlecliffian (middle Pleistocene, Brunhes Normal Chron) faunas are not preserved on land anywhere south of Wanganui Basin to be able to confirm or deny this possible faunal migration. Biostratigraphy Figure 1isa time-scale diagram for the last 2 million years in New Zealand, repeated from Beu (2004, fig. 4). Figure 2 shows the time ranges of most of the bivalves discussed in this paper (some taxa with entirely earlier time ranges or no biostratigraphic utility are discussed in the text but not included in Fig. 2). As in Beu (in Cooper 2004), I ignore the subdivisions based on invisible parameters such as magnetic reversals, suggested by Carter (2005a,b, table 1), for reasons given by Beu (2001), Wilson (in Cooper 2004, p. 225) and Turner et al. (2005, p. 216). I adopt the timescale of Cooper (2004) and the definitions of New Zealand local stages discussed by me previously (Beu 2001) and adopted by me (Beu in Cooper 2004): HaweranCastlecliffian boundary at Rangitawa Tephra, 0.34 Ma (in Rangitawa Stream, Rangitikei), Castlecliffian-Nukumaruan boundary at Ototoka Tephra, 1.63 Ma (on the coast east of Ototoka Stream mouth), Nukumaruan-Mangapanian boundary at the base of Hautawa Shellbed (proposed but not formally defined, on Hautawa Road, between Turakina and Murimoto valleys, north of Hunterville; Beu in Cooper 2004, p. 217), and Mangapanian-Waipipian boundary at the base of Mangapani Shellbed (in Mangapunipuni Stream, Waitotara Valley). These stage boundary definitions, and particularly the new Castlecliffian-Nukumaruan boundary defined by me (Beu in Cooper 2004, p. 220), are important for allowing the use of the guide fossils discussed here. A boundary in a different position, as suggested by Carter (2005a,b), would be impractical as it would not be definable by biostratigraphy, just as the Nukumaruan and Castlecliffian substages re-recognised by Carter (2005a,b) are not recognisable by biostratigraphy, and have no practical purpose. Figure 2 is constructed to demonstrate: (a) A group of species, and the genera Glycymeris (sensu stricto), Patro, Pteromyrtea, Lutraria (sensu stricto), L. (Psammophila), Dosinia (Raina), and Eumarcia, which became extinct in New Zealand at the end of Nukumaruan time, and so provide important criteria for identifying the Nukumaruan-Castlecliffian boundary. (b) Some taxa formerly thought to have biostratigraphic utility but now known to range right through this interval (Dosinia (Austrodosinia) anus (Philippi, 1848) (= D. horrida Marwick, 1927), Austrovenus stutchburyi (= A. crassitesta (Finlay, 1924)), Protothaca crassicosta (Deshayes, 1835)). (c) Long-ranging species that became extinct during Castlecliffian-Haweran time (Limnoperna huttoni during OIS 13, Barytellina crassidens Marwick, 1924 probably during OIS 9). (d) The differing time ranges of Pecten novaezelandiae in Wanganui Basin (first occurrence during OIS 19) and the East Coast Basin (first occurrence at least as early as OIS 29).


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(e) The evolving lineage of Mactra (Maorimactra) marwicki n. sp. (late Nukumaruan)—M. carteri n. sp. (OIS 45?-19)—M. ordinaria (E. A. Smith, 1898) (OIS 17-Recent). (f) Short-ranging Castlecliffian species (Mactra carteri; Paphies delta n. sp., OIS 31?-15; My adora kaiiwiensis Powell, 1931, OIS 29-17), including some that evolved or became extinct during the mid-Pleistocene transition. (g) Two cases are also shown of distinctions between closely phylogenetically related species that further help to identify the Nukumaruan-Castlecliffian stage boundary (Mactra marwicki evolved into M. carteri, Myadora waitotarana evolved into M. striata). The biostratigraphically useful taxa in this figure supplement those shown and discussed previously by me (Beu 2004, fig. 5), together providing means of distinguishing Nukumaruan from Castlecliffian faunas, and of subdividing Castlecliffian and Haweran time. MID-PLEISTOCENE TRANSITION: One aim of this series of papers is to recognise evidence for origination and extinction caused by climate change during the last 2 m yr and, in particular, to what degree origination and extinction coincided with the mid-Pleistocene transition (MPT). This is the period when glacial-interglacial cycles gradually changed from a 41 000-yr periodicity to the roughly 100 ka periodicity that has operated for the last 650 ka. An important caveat on the interpretation of the MPT was pointed out by Ruddiman (2003) and Maslin & Ridgwell (2005; see particularly fig. 10), although Maslin & Ridgwell (2005) preferred to label it the mid-Pleistocene revolution (MPR), and considered that it operated over at least 1 Ma-650 ka. Rather than a period when actual 100 ka cycles of Earth's orbital parameters (usually labelled eccentricity cycles) came to dominate glacial-interglacial cycles, these authors pointed out that a 100 ka cyclicity does not match the insolation record; the time between cycle peaks varied between 77.1 and 119.5 ka during the last 850 ka. Each apparent cycle in the familiar saw-tooth pattern of roughly 100 ka cycles is actually a combination of four or five precessional cycles, formed by the combination of orbital frequencies at 12,23,41,95, 125, and 400 ka. The pattern is strongly affected by powerful feedbacks within the Earth, such as rapid and complete deglaciation events and corresponding albedo changes at the cycle peaks. Rather than a period when 100 ka cycles came to dominate glacial-interglacial change, the MPT is better regarded as the time of onset of the non-linear feedbacks that have dominated the climate since 650 ka. Whether this onset should be expected to have caused an unusual number of originations and extinctions is unclear. Empirical demonstration of whether an unusually high frequency of origination and/or extinction events coincides with the MPT then becomes more significant than before; did similar changes occur during this period of feedback onset as were expected when it was interpreted as a period of change to 100 ka climate cycles? Figure 2 demonstrates that the extinction of Myadora kaiiwiensis and Mactra (Maorimactra) carteri, the appearance of Pecten novaezelandiae in Wanganui Basin, and the origination of Mactra ordinaria all occurred within the MPT. Four events seems little different from the expected background frequency. Addition of the events recognised by Beu (2004, fig. 4) reveals a few more within the MPT—although I previously (Beu 2004) focused on the most geologically recent molluscan faunal changes within New Zealand, apparently biasing the record. This figure adds the appearance of Prototyphis angasi (Crosse, 1863) and the reappearance of Limaria orientalis (A. Adams & Angas, 1850) in Wanganui Basin, and the appearance of Crassaostrea gigas (Thunberg, 1793) in the Bay of Plenty within the MPT (the last is poorly dated, but the possible earlier age would locate it more firmly within the MPT than it is now).

Fig. 1 New Zealand latest Pliocene-Holocene time-scale adopted here (slightly modified from Beu 2004, fig. 4). Correlation of oxygen isotope stages with the geomagnetic polarity time-scale adopted from Carter & Naish (1999). (Late Pleistocene is applied only to the Last Glaciation, OIS 2.)


GEOMAGNETIC POLARITY TIME - SCALE AGE, Ma

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OXYGEN ISOTOPE STAGE

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NZ STAGE

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