CESARE EMILIANI Institute of Marine Science, University of Miami, Miami, Fla.

Paleotemperature Analysis of the

Caribbean Cores A254-BR-C and CP-28

Abstract: Two cores from the central Caribbean been extended to an estimated age of 375,000 years (cores A254-BR-C and CP-28), which include ago, but the extension should not be considered older Pleistocene sediments, have been analyzed generally valid until substantiated by isotopic by the O18/O16 method. Core A254-BR-C has analysis of suitable cores as yet not available. been dated, in part, by C14 and Pa231/Th230 The methods used by Ericson, Ewing, Wollin, measurements. Both apparently contain major and associates, for estimating past temperatures hiatuses, but their stratigraphy has been clarified from the micropaleontology of deep-sea cores, and by correlations among the isotopic temperature the correlations advocated between deep-sea and curves and the curves representing the percentages continental stratigraphies are critically reviewed. of right-coiled specimens of Globorotaha truncatuh- The evidence provided by cores A254-BR-C and noides, together with correlations among the core CP-28 adds to the contention that the repeated levels where Globorotaha menardii flexuosa disap- glaciations of the Pleistocene were triggered by pears and among other levels where Globorotalia summer insolation minima in the high northern truncatulinoides becomes rare. The generalized latitudes. temperature curve, previously constructed, has

CONTENTS Introduction 129 on shells of Globigerinoides sacculifera . 144 Acknowledgments 131 Analysis of cores A254-BR-C and CP-28 .... 131 Figure Review of methods used by Ericson, Ewing, and 1. Geographic locations of Caribbean cores. . . . 131 associates in analyzing and evaluating the 2. Core A254-BR-C 132 stratigraphic record of deep-sea sediments . 136 3. Core CP-28 132 Conclusion 141 4. Correlations among cores A179-4, A172-6, A254- References cited 141 BR-C, and CP-28 133 Appendix 1. Core A254-BR-C. Oxygen isotopic 5. Generalized temperature curve 136 analyses on shells of Globigerinoides sacculifera 144 6. Cores A179-4 and A172-6 138 Appendix 2. Core A254-BR-C. Oxygen isotopic 7. Comparison of generalized climatic zonation of analyses on shells of Globorotalia menardii . 144 deep-sea cores proposed by Emiliani with Appendix 3. Core CP-28. Oxygen isotopic analyses that proposed by Ericson and others . . .140

sea cores from the Atlantic and adjacent seas INTRODUCTION revealed the temperature oscillations very The geochemical study of deep-sea cores clearly (Emiliani, 1955a; 1955b; 1958; Rosholt (Arrhenius, 1952; Emiliani, 1955a; 1955b; and others, 1961; 1962). The background 1958; 1961; Rosholt and others, 1961; 1962; noise of the temperature curves of the various and references therein) has cast considerable cores, caused by the imperfect mixing of the light on the major events of the Pleistocene. sediment by bottom animals, the sampling Because of the nearly instantaneous heat ex- statistics, the analytical error, etc. (cf. Emiliani, change between ice caps and ocean water, the 1961) was filtered out by cross-correlation of oscillations of the continental ice caused the various cores, and a generalized tempera- synchronous oscillations in the temperature ture curve was constructed (Emiliani, 1955a; of the ocean water. The Atlantic and adjacent 1958; 1961). This curve was divided into high seas underwent especially strong temperature temperature stages (identified by odd integers oscillations because of the nearness of the increasing with age) and low temperature major northern ice sheets. Oxygen isotopic stages (identified by even integers increasing analysis of fossil pelagic Foraminifera in deep- with age). Most maxima and minima reach Geological Society of America Bulletin, v. 75, p. 129-144, 7 figs., February 1964 129

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equivalent values, but some (stages 3, 8, and and because of the local pattern of vertical 12) do not. circulation of the sea water (Emiliani, 1955a). The climatic history of the more recent Considering that Globorotalia menardii tumida portion of the Pleistocene has been considera- and Globorotalia menardii menardii appear to bly clarified by the oxygen isotopic analysis and deposit their shell material at about the same the absolute dating of the deep-sea cores previ- depth (Emiliani, 1954, Table 2), a comparison ously published, but the climatic history of of the isotopic temperatures given by G. the earlier Pleistocene is still largely obscure. menardii tumida in core 58 with those given Very few continuous sections of marine or by G. menardii menardii in the Caribbean core continental deposits representing appreciable A179-4 (Emiliani, 1955a, Figs. 2 and 11) sug- portions of the earlier Pleistocene time have gests that the temperature variations at the been described in adequate detail. The long surface of the eastern equatorial Pacific were deep-sea cores nos. 58 and 62 from the eastern about twice as large as those mentioned. Thus, equatorial Pacific (Arrhenius, 1952) penetrate, the temperature decrease shown by the lower probably with sedimentary continuity, sedi- half of core 58 would be about 6°C for the ment layers belonging to the older Pleistocene surface water, and the temperature fluctuations or the Pliocene. The carbonate percentage shown by its upper half would be about 4°C oscillates markedly throughout these cores, (as compared to about 9°C in the equatorial suggesting appreciable climatic variations. Atlantic and the Caribbean). These values are Paleotemperature analysis of core 58 showed an not corrected for the isotopic effect of the appreciable temperature decrease (about 3°C) sea water (cf. Emiliani, 1955a). from the bottom to the middle of the core, Oxygen isotopic analysis of the continuous and temperature oscillations of about 2°C in Plio-Pleistocene section of marine sediments the rest (Emiliani, 1955a, Fig. 11). These at Le Castella, Calabria, southern Italy, re- oscillations, however, do not offer a clear vealed marked temperature fluctuations even picture of climatic changes because of the in the Pliocene. These increase in amplitude relatively small value of the secular temperature in the earliest Pleistocene without, however, change in the equatorial Pacific, because of the attaining the amplitude characteristic of the deeper habitat (with respect to shell deposition) later Pleistocene (Emiliani and others, 1961). of the foraminiferal species available for iso- A progressive decrease of the secular tempera- topic analysis (Globorotalia menardii tumida)1, ture maxima and minima was also observed, but no sudden, large temperature decrease was * Oxygen isotopic analysis showed that Globorotalia noticed across the sharply defined paleonto- deposits its shell material at average depths greater than logical boundary. Pollen analysis of relatively Globigerinoides and other genera of pelagic Foraminifera long sections of continental sediments in (Emiliani, 1954; 1955a; 1958). This was later substanti- northern Italy, Poland, and the Netherlands ated by the observation that Globorotalia shells from deeper plankton tows are thicker than those from shal- of a pelagic foraminiferal species is deposited at some lower tows (Be, 1960; Ericson and others, 1961; Ericson depth below the surface, "... the reliability of the and Wollin, 1962). Be (1960) states that the measured chemistry of the shell as an indicator of conditions in the differences in isotopic temperatures among different euphotic zone is seriously impared." This statement is species of pelagic Foraminifera from the same deep-sea incorrect. Since the information contained in a bio- core samples can be interpreted in terms of seasonal dif- chemical system refers only to the specific environment ferences rather than in terms of different depth habitats where the system was formed, the O18/O16 ratios in shells of shell deposition as proposed by the writer (Emiliani, of pelagic foraminiferal species refer to the depth (and 1954; 1955a). Be's interpretation cannot be accepted season, if seasonal variations occur) at which the average for most of the cores, which were raised in areas where no shell deposition takes place. Since different species of appreciable seasonal temperature variations exist (Carib- pelagic Foraminifera deposit their shell material at dif- bean; equatorial Atlantic; equatorial Pacific: see ferent average depths (Emiliani, 1954), a way is provided Emiliani, 1954; 1955a; this paper). As a result, the to evaluate not only the surface temperature but also measured temperature differences can only be due to that at the various depths through the euphotic zone different depth habitats of average shell deposition, (See Emiliani, 1955a, Fig. 2). Therefore, far from pro- because the low temperatures observed occur only at ducing an impairment, the depth spectrum of shell depth and not at the surface at any time of the year. deposition of pelagic Foraminifera provides us with very Where seasonal temperature variations are appreciable, valuable additional information. A statistical analysis the seasonal effect was discussed in detail and properly showing that this spectrum has changed little during the considered (Emiliani, 1955b, 1958). Pleistocene (Emiliani, 1955a) stresses the reliability of Ericson and others (1961) state that if part of the shell the information as far as fossil assemblages are concerned.

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revealed marked climatic fluctuations, some A. Rusnak and C. Fleming for directing the of which have been correlated with the Giinz coring operations; and to G. Wollin for the glaciation and others which have been assigned valid opinion that the bottom sections of cores to earlier (Donau) cold stages (Lona, 1950; A254-BR-C and CP-28 consist of sediments Venzo, 1953; Lona and Follieri, 1957; Szafer, disturbed by coring. Financial support was 1954; Zagwijn, 1959; 1960). given by the National Science Foundation The preceding evidence indicates that tem- and the Office of Naval Research. perature fluctuations of reduced amplitude were already occurring before the beginning ANALYSIS OF CORES of the Pleistocene; that these fluctuations con- A254-BR-C AND CP-28 tinued, with increasing amplitude, during the Oxygen isotopic analysis of suitable long Calabrian; and that about 300,000 years ago, cores from the Atlantic and/or adjacent basins,

VL._EZ?=-~—4 1-

Figure 1. Geographic locations of Caribbean cores

the temperature fluctuations had already penetrating sediments older than 300,000 years, reached a maximum amplitude which has provides a clearer understanding of the cli- remained essentially constant since. The latter matic history of the earlier Pleistocene. Two are believed to represent the major glacial and such cores, both from the Caribbean, have interglacial ages of the Pleistocene. been analyzed recently, and one has been dated, in part, using both the C14 and Pa231/ ACKNOWLEDGMENTS Th230 methods. Core A254-BR-C (15°17'N., The author is grateful to J. Zeigler and W. 72°53.5'W., 2968 m of depth, 1033 cm long) Athearn of the Woods Hole Oceanographic was raised by the Woods Hole R/V ATLANTIS; Institution for collecting core A254-BR-C; to core CP-28 (16°47.7'N., 74°26.4'W., 3036 m R. Revelle for making available to the Institute of depth, 1406 cm long) was raised by Scripps' of Marine Science, University of Miami, the R/V SPENCER BAIRD on loan to the Institute R/V SPENCER F. BAIRD for a 30-day expedition of Marine Science, University of Miami. to the Caribbean during which core CP-28 Figure 1 shows the locations of these two and other deep-sea cores were raised; to G. cores and other Caribbean cores to be dis-

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cussed later. Figures 2 and 3 show the paleo- deposition (See footnote 1). The Pa231/Th230 temperature records of cores A254-BR-C and ages of core A254-BR-C and part of its paleo- CP-28 together with the weight percentages temperature record were published by Rosholt of the sediment fractions larger than 62 n (See and others (1962); the C14 ages have been pub- also Appendixes 1-3). Available C14 and lished by Rusnak and others (1963).

DEPTH BELOW TOP [cm) Figure 4. Correlations among cores A179-4, A172-6, A254-BR-C, and CP-28. Isotopic tempera- ture curves based on the pelagic foraminiferal species Globigerinoides sacculifera. Numbers identify core stages; letters identify core sections; downward arrows indicate last (most recent) occurrence of Globorotalia menardii flexuosa; upward arrows identify core levels in which Globorotalia truncatulinoides becomes rare. Absolute ages by C14 and Pa231/Th230 measurements

Pa231/Th230 ages are also shown. Globigerinoides Both the oxygen isotopic temperatures and sacculifera has been used for the isotopic the weight percentages of the sediment fraction analyses. In the lower portion of core A254- larger than 62 /LI show marked fluctuations BR-C, where Globigerinoides sacculifera is rare, through most of the two cores. Neither core Globorotalia menardii has been used. As usual, represents a continuous stratigraphic section: this species gives isotopic temperatures several one important hiatus occurs in core A254- degrees centigrade lower than Globigerinoides BR-C (at 610 cm) and two in core CP-28 (at sacculifera (Emiliani, 1954; 1955a, Fig. 2), 400 and 520 cm). Hiatuses in deep-sea cores indicating a greater depth habitat for shell are viewed with mixed feelings by the writer:

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they make correlations among cores much more menardii flexuosa is continuously abundant. difficult, and yet they may bring older sedi- This subspecies, absent between 210 and 190 ments within sampling reach. cm, is again abundant between 180 and 150 Generally, the shape of the isotopic tempera- cm, an anomalous occurrence indicating that ture curve within given high or low temperature core A172-6 is somewhat disturbed between stages is not sufficiently characteristic to allow 150 and 250 cm (See also Kemp and Eger, in identification of these stages from the shape press). The disturbance may explain the absence of the curve alone. One exception is stage 5, of an expected peak of left-coiled specimens of where the isotopic temperature curve is charac- G. truncatulinoides in the neighborhood of 220 teristically asymmetric and, in general, easily cm, and the fact that the isotopic temperature recognizable (cf. Emiliani, 1961, Fig. 7). curve of stage 5 does not exhibit the character- Proper identification of deep-sea core stages istic asymmetrical shape. below a hiatus of unknown magnitude may be Except for the relatively minor disturbance made by absolute dating (if possible), or in core A172-6 mentioned, cores A179-4 and through the identification of given layers by A172-6 appear to represent nearly continuous the uniqueness of suitable parameters. In the and undisturbed sections of Globigerina-ooTR present case, the first (topmost) hiatus in either sediments. Core CP-28 appears essentially free core is near the limit of Pa231/Th230 dating, so of major disturbances from the top to 400 that all layers below it are expected to give cm, and core A254-BR-C from the top to infinite ages. Parameters which are, at least in 610 cm. At and below these levels, important part, temperature dependent (as the relative hiatuses occur. By carefully and jointly evalu- abundances of different species of pelagic ating the information provided by the paleo- Foraminifera or their ratios) are of no greater temperature curves and the curves representing use than the temperature curves alone. Param- the percentages of the right-coiled specimens eters which are largely or totally temperature- of Globorotalia truncatulinoides, and by noticing independent are potentially much more useful. the occurrence of a stratigraphic level where These include the first or last appearance of this otherwise common species becomes rare foraminiferal species; the presence or absence, (490-500 cm in core A179-4; 580 cm in core within a restricted stratigraphic interval, of A172-6; and 410-420 cm in core CP-28), it has species which are, respectively, absent or been possible to establish the correlations shown abundant through the rest of the cores; in Figure 4. For convenience, the cores have temperature-independent changes in the mor- been divided into sections A to M. Sections phology of the foraminiferal shells; and temper- F and I are missing in core CP-28, and Section ature-independent geochemical parameters. H is greatly reduced. In core A254-BR-C, A convenient parameter is the coiling Sections G, H, and I are missing. Section J direction of the shells of Globorotalia truncatuli- is the lowest section of core A172-6, and in- noides. Although these shells are predominantly cludes an early cold stage (No. 14) tentatively right-coiled, left-coiled specimens are common correlated with the Giinz glaciation (Emiliani, in certain core layers. Ericson and others 1955a). The coiling direction of G. truncatuli- (1954) and Ericson and Wollin (1956a) used noides indicates that this stage is represented this characteristic to correlate deep-sea cores. by the temperature minima at 530-540 cm in Curves representing both the isotopic tempera- core CP-28 and at 630-670 cm in core A254- tures and the percentages of right-coiled BR-C. In both cores an earlier temperature specimens of G. truncatulinoides are shown in minimum is present (690 cm in core CP-28 and Figure 4 for cores CP-28, A254-BR-C and the 760-780 cm in core A254-BR-C), possibly two Lament cores A172-6 and A179-4 (data, representing an Early Giinz stage, the Ebu- for the latter, from Ericson and Wollin, 1956a, ronian of Zagwijn (1959; 1960), and the Tables 4, 5). All available C14 and Pa231/Th230 Mizerna I and I/II of Szafer (1954). Hiatuses dates are also shown. The last (topmost) occur- of unknown magnitude may exist in the lower rence of Globorotalia menardii flexuosa is indi- portions of Section L in core CP-28, a problem cated by downward arrows on the temperature which may be resolved only by cross-correlation curves of the various cores. For core A172-6, with suitable, long cores as yet unavailable. The the downward arrow does not actually repre- bottom sections of the two cores (Sections M) sent the last occurrence, but, rather, the top yielded temperature curves showing reduced of a long core section throughout which G. variations. These were believed to represent a

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portion of the Pleistocene preceding the Giinz, signed to the close temporal relationship be- but G. Wollin showed the writer, quite con- tween stage 16, with the usual delay of a few clusively, that the sediments of the two sections thousand years, and the marked insolation have been disturbed during coring. The shape minimum of the Milankovitch curve at 321,000 of the temperature curve of Section M of core years ago (Emiliani, 1955a, Fig. 14). CP-28 indicates that some information has The generalized temperature curve previ- been preserved, but the uncertainty introduced ously constructed (Emiliani, 1955a; 1961; by the disturbance is too great to warrant any Rosholt and others, 1961) is reproduced in speculation. Sections M of the two cores, there- Figure 5 with an extension toward the earlier fore, should be disregarded. time based on the paleotemperature records of All C14 and Pa231/Th230 ages (Figs. 2 and 4) cores A254-BR-C and CP-28. Since this ex- are internally consistent, including the Pa231 tension is based on only two cores, it should /Th230 date at 31-40 cm in core A254-BR-C not be considered generally valid until sub- (which has an error of +4000 years; Rosholt stantiated by isotopic analysis of other suitable and others, 1962). cores as yet unavailable. The time scale from It was shown (Rosholt and others, 1961; see the present to about 150,000 years ago is based also Rusnak, 1963; Rosholt and others, 1963) on C14 and Pa23l/Th230 measurements on that the rates of sedimentation of carbonate selected core samples (Rubin and Suess, 1955; fraction larger than 62 jt, the carbonate fraction 1956; Rosholt and others, 1961; 1962). The smaller than 62 fj., and the noncarbonate ages of earlier temperature fluctuations have fraction do not change markedly in the two been estimated by extrapolation (Emiliani, Caribbean cores A240-M1 and A179-4 when 1955a), and as shown above. This time scale averaged over intervals of tens of thousands of is probably correct to within 10 per cent from years. A similar conclusion holds for the bulk the present to about 150,000 years ago, and to sediment which consists of the three factions within 20 per cent from 150,000 to 375,000 combined.2 From the Pa23I/Th230 age of the years ago. temperature minimum of stage 6 (about In earlier papers (Emiliani, 1955a; 1958; 110,000 years; see Rosholt and others, 1961; 1961) stage 14 was tentatively correlated with 1962) and its stratigraphic position in the cores the Giinz glaciation. This and the other corre- illustrated in Figure 4, average rates of sedi- lations for the younger stages were based on mentation for each core section including stages the simple argument that since the present time 1 to 6 may be calculated. (stage 1) is a full interglacial, earlier stages with Applying the pertinent rates, thus calculated, similarly high temperature should represent to the lower portions of cores A254-BR-C and major interglacials; and since the low-tempera- CP-28, and assuming that stage 14 has been ture stage 2 represents a full glaciation (the properly identified in the two cores, an age of Main Wiirm), earlier stages with similarly low about 315,000 years may be estimated for temperatures should represent major glacia- stage 16. Although this age is obviously un- tions. certain, some significance may perhaps be as- The preceding evidence indicates that, analo- gously to the Wiirm, the Giinz glaciation con- 2 It is understandable that rates of sedimentation of sisted of two major phases, for which the names undisturbed deep-sea sediments, when averaged over of Early Giinz (stage 16) and Main Giinz cine or more glacial/interglacial cycles, should remain (stage 14) may be used. Thus, stages 16 and 14 approximately constant for much of the Pleistocene. In may correlate, respectively, with the Giinz I fact, because of the unique character of deep-sea sedi- and Giinz III of Venzo (1953) and Lona and mentation, a change in the average would require major Follieri (1957); with the Eburonian and the alterations in the physiography of the Earth, or in the Menapian of Zagwijn (1959, 1960); and with biological balance of the high seas. Thus, it is not surpris- the Mizerna I and I/II and the Mizerna II/III ing that the time scale previously estimated (Emiliani, of Szafer (1954). A close similarity, in fact, 1955a) by extrapolating rates of sedimentation calculated across a glacial/interglacial cycle (Main Wiirm to the may be noticed between the generalized present) was closely confirmed by Pa231/Th230 age temperature curve (Fig. 5, stages 14 and earlier) measurements (Rosholt and others, 1961; 1962). As- and the paleoclimatic curves obtained by pollen sumptions of constancy of rates of sedimentation outside analysis of the Giinz and pre-Giinz sections at of the deep-sea (cf. Eardley and Gvosdetsky, 1960) are Leffe (cf. Venzo, 1953, Figs. 5,6; Lona and subject to question. Follieri, 1957, Figs. 3-5) and in Holland (cf.

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Zagwijn, 1959, Table 1; 1960, Fig. 8). If these Ericson and Wollin (1956a; 1956b), Ewing correlations are correct, the Giinz would range and others (1958), and Ericson and others between 325,000 and 265,000 years ago.3 (1961) have published paleoclimatic and strati- The more common definitions of the Plio- graphic interpretations of deep-sea cores which Pleistocene boundary are (1) the beginning are markedly at variance with those obtained of the first major glaciation (i.e. Giinz); (2) the by the writer. Insofar as the discrepancy ap- first appearance of Elephas, Equus, and pears to arise not from the data published by Leptobos; and (3) the first appearance of these authors, but from the interpretations Cyprina islandica and Anomalina baltica in the given, a critical review is necessary. Late Cenozoic sections of Italy (the "official" definition). These events are most likely not REVIEW OF METHODS USED BY synchronous. Their ages are unknown, but ERICSON, EWING, AND ASSOCIATES ages as early as 3.2 X 106 years have been ob- IN ANALYZING AND EVALUATING tained for Villafranchian assemblages (Evern- THE STRATIGRAPHIC RECORD OF den and others, 1964). Also, an early glaciation DEEP-SEA SEDIMENTS of the Sierra Nevada, California, was K/Ar Ericson and Wollin (1956a; 1956b), Ewing dated at 960,000 years B.P. (Evernden and and others (1958), and Ericson and others

350 x 1000 YEARS B.P. Figure 5. Generalized temperature curve

others, 1963).4 Along, pre-Giinzian Pleistocene (1961) estimated visually the relative abun- time is thus indicated. dances of different species of pelagic Forami- nifera in deep-sea cores from the Atlantic, the 3 This age is close to the K/Ar age of about 350,000 years (or less, because of possible inherited argon) deter- Caribbean, and the Gulf of Mexico. Select- mined by Evernden and others (1957) and by H. J. ing, then, the polytypic species Globorotalia Lippolt (Ph.D. thesis, Ruprecht-Karl-Universitat, Heid- menardii as an especially reliable temperature elberg, 1961) for volcanic-ash minerals belonging to indicator, and disregarding such species as falls that occurred while sediments of the Jiingere Sphaeroidinella dehiscens and Pulleniadna ob- Hauptterrasse of the Lower Rhine were being deposited. liquiloculata, which are typically warm-water These terrace deposits were assigned to the "Mindel II" species (Bradshaw, 1959; Phleger, 1960, Fig. by Soergel (1939) but are now assigned to the Giinz by 68), they reconstructed the climatic variations Woldstcdt (1958). The age of about 300,000 years through the cores. In estimating foraminiferal originally estimated by the writer for the Giinz (Emili- am, 1955a) prompted some authors (e.g. Eardlcy and abundances, they introduced an artificial Gvosdetsky, 1960) to state that the writer proposed a boundary condition by classifying as "very duration of 300,000 years for the whole Pleistocene. abundant" species represented by "more than This is incorrect. In the same paper in which age of 100 specimens per tray spread" (Ericson and about 300,000 years was first suggested for the Giinz Wollin, 1956a), so that no distinction was made (Emiliani, 1955a), an age of about 600,000 years was among numbers greater than 100. Some species estimated for a "Plio-Pleistocene boundary" in the are rare or absent throughout the cores, others eastern equatorial Pacific core 58, with the cautionary are abundant, or very abundant. The data remark that correspondence with the officially adopted definition of Plio-Pleistocene boundary was hypothetical published for species having abundance ranges (Emiliani, 1955a, p. 562). between 0 and 100 per tray spread in the ^ Although, of course, it may be just a coincidence, Caribbean cores A179-4 and A172-6 (Ericson the fact is that this K/Ar date is close to the age (970,000 and Wollin, 1956a, Tables 4, 5) were published years B.P.) of a major insolation minimum of the Milan- as graphs by Emiliani (1957). The graphs of kovitch curve (See Emiliani, 1955a, Fig. 14). Sphaeroidinella dehiscens and Pulleniatina

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obliquiloculata, and of the temperate species The relative abundances of the components Globigerina inflata, are reproduced in Figures of a system (in this case, pelagic Foraminifera 6A and 6B, curves E, F, and G. The abundance in deep-sea core samples) form a closed statisti- curve of Globorotalia menardii is also repro- cal system in which the quantities involved are duced (curves H) showing, in the very broad, mutually dependent. The restrictions obtaining flat peaks, the effect of the artificial boundary for such a system are removed by taking the condition mentioned above. ratios of the relative abundances of two (or Close inspection of curves E, F, G, and H more) components. Curves C and D in Figures in Figures 6A and 6B shows that the correlation 6A and 6B show the ratios of Sphaeroidinella of the foraminiferal abundances of the species dehiscens and Pulleniatina obliquiloculata to considered to each other and to the isotopic Globigerina inflata (a temperate species). As temperature (curves A) may be direct or in- may be seen, these two curves correlate with verse, may change from direct to inverse and each other and with the isotopic temperatures vice versa through the cores, or may vanish far better than the other micropaleontological altogether. In general, however, the abun- curves. It is apparent, therefore, that the rela- dances of Sphaeroidinella dehiscens and Pul- tive abundance ratios of warm-water species to leniatina obliquiloculata would seem better temperate species (or to cold-water species, if related to each other and to the isotopic available) provide a sounder basis for paleo- temperatures (although it may not be so in climatic reconstructions than the relative specific core sections) than to the abundance of abundances alone, as one would expect on Globorotalia menardii. The abundance of G. theoretical grounds. The apparent superiority menardii is directly proportional to the abun- of the abundance ratios is further substantiated dance of Sphaeroidinella dehiscens and Pul- by the mathematical analysis of Kemp and leniatina obliquiloculata, and to the isotopic Eger (in press). temperatures, in the upper portions of the The weight percentage of the sediment cores; it is independent of these parameters fraction larger than 62 ju (or 74 /*) in undis- in the mid-portions of the cores (probably turbed Globigerina-oo7.z cores from the Atlantic because of the artificial boundary condition and adjacent seas is often directly proportional mentioned above); and, in the lower portions to temperature (sometimes showing an amaz- of the cores, it is either directly or inversely ingly high correlation; see Emiliani, 1955a, proportional, depending on the core. Thus, G. Fig. 8). This relationship was first recognized mencrdii is generally "common" or "abundant" by the writer (Emiliani, 1955a); it was then in the bottom meter of core A179-4 from the extensively applied by Ericson and Wollin Caribbean, whereas it is absent in the equiva- (1956a, 1956b), Ewing'and others (1958), and lent section of core A172-6 from the same Ericson and others (1961); it was investigated region. The artificial boundary condition was by Broecker and others (1958), and discussed later removed by computing the number of in some detail by Emiliani and Mayeda (1961) specimens of G. menardii per milligram of the and Rosholt and others (1961). For suitable sediment fraction larger than 74 ju, with the cores, the weight percentage of the sediment result that a better correlation with the isotopic fraction larger than 62 n (or 74 /i) provides a temperature and the other species mentioned conveniently rapid method for preliminary above was found in the mid-portions of the stratigraphic investigations. A marked disagree- cores (Ericson and Wollin, 1956b, Fig. 4; ment between this parameter and the evidence Ericson and others, 1961, Fig. 41; see Figs. 6A provided by Globorotalia menardii in the lower and 6B, curves I). However, disagreement portions of the cores as interpreted by Ericson remains about the lower portions of the cores and Wollin (1956a; 1956b) and Ericson and where G. menardii is less abundant or absent. others (1961) may be noticed (See Fig. 6A, Obviously, factors other than temperature, curve B), while a marked agreement exists both ecologic and nonecologic, play a role with the other parameters (curves A, C, D, in determining the relative abundances of E, and F).5 pelagic foraminiferal shells in deep-sea sedi- 0 ments. This should have been suspected from Considerable postdepositional solution of carbonate phase (especially at about 550, 700 and 800 cm below the observation that the warm-water species top) is evident in core A172—6, which was raised from Sphaeroidinella dehiscens and Pulleniatina ob- the depth of 4160 m. As a result, the percentage of the liquiloculata remain generally abundant in the sediment fraction larger than 74 p generally shows a poor lower portions of the cores where G. menardii correlation with the other temperature-dependent may be entirely absent. parameters (See Fig. 6B).

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/75/2/129/3427567/i0016-7606-75-2-129.pdf by guest on 01 October 2021 CM BELOW TOP A Figures 6. A, core A179-4, and B, core A172-6. Curve A, Isotopic temperatures, based on the pelagic foraminiferal species Globigerinoides sacculifera; B, weight percentages of sediment fraction larger than 74 ju; C, log of relative abundance ratio Sphaeroidinella dehiscens / Globigerina inflata; D, log of relative abundance ratio Pulleniatina obliquiloculata/Globigerina inflata; relative abundances of E, Sphaeroidinella dehiscens, F, Pulleniatina obliquiloculata, G, Globigerina

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/75/2/129/3427567/i0016-7606-75-2-129.pdf by guest on 01 October 2021 inflata, and H, Globorotalia menardii, expressed by abundance symbols V = very abundant, A = abundant, C = common, F = frequent, R = rare, and X = absent (from Ericson and Wollin, 1956a); I, number of Globoortalia menardii shells per milligram of sediment fraction larger than 74 M (From Ericson and Wollin, 1956b); J, paleoclimatological and stratigraphic interpretation by Ericson and others (1961)

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Since the isotopic temperatures, the weight generalized climatic zonation of the cores con- percentage of the sediment fraction larger sisting of six zones identified by the letters u than 62 /* (or 74 n), and significant micro- to z in order of decreasing age (cf. Figs. 6A and paleontological parameters show stages 11 and 6B, curves J). Zones z, x, and v are considered 13 to be warm, the question may be asked as "warm," and zones y, w, and u are considered to why Globorotalia menardii is less abundant "cold." (core A179-4) or absent (core A172-6) in these If more accurate micropaleontological meth- two stages while it is generally abundant in ods are used, such as the abundance ratios the other warm stages. There are, of course, mentioned, a markedly different climatic zona- many ecologic factors other than temperature tion is obtained for the middle and lower which may affect adversely a given species. portions of the cores. This zonation, which is

WARM

100 150 200 250 300 x 1000 YEARS B.P Figure 7. Comparison of generalized climatic zonation of deep-sea cores proposed by Emiliani (1955a; 1958; 1961) and that proposed by Ericson and others (1961). Curve B (Emiliani, 1961, Fig. 9) is based on O18/O16 measurements and is supported by foraminiferal ratios discussed in text and by weight percentages of sediment fraction larger than 62 or 74 fj.. Curve A (Ericson and others, 1961, Fig. 24) is based on relative abundances of Globorotalia menardii under assumption that these abun- dances are proportional to temperature throughout cores. Curve A is not supported by other micropaleontological, geochcmical, or sedimentological parameters in its earlier portion, indicating that the assumption is incorrect.

In the case of pelagic Foraminifera, which are close to that provided by the O18/O16 measure- found alive from the surface down to more ments, obviously gives a more accurate in- than 1000 m (Phleger, 1960, ch. 5, and refer- terpretation of the climatic variations occur- ences therein; Be, 1960; Jones, in press) but ring during the time the sediments of the apparently perform certain functions such as cores were being deposited. The two zonations CaCOg deposition within restricted depth are compared in Figure 7. ranges (See footnote 1; Emiliani, 1954), a Ericson and Wollin (1956a; 1956b) and small, adverse change within a restricted depth Ericson and others (1961) regard the last high- range may result in the temporary (and local) temperature stage (stage 5 or zone x: see Fig. eclipse of a given species. The conclusion that 7) as representing an interstadial of the last a given core section was deposited at low glaciation.6 A similar interpretation is given by temperatures should not be considered unless all warm-water species are rare or absent, not 6 Ericson and others (1961, p. 280) confuse the Wis- only one. Inspection of Figures 6A and 6B consin sensu lato (which includes both Early and Main Wisconsin) with the Main Wisconsin or "classical" shows that the evidence suggesting that stages 14 11 and 13 are warm far outweighs the partial Wisconsin of Flint (1957). As is well known from C data, the latter ranged from about 30,000 to about evidence to the contrary provided by G. 11,000 years ago, whereas the Wisconsin sensu lato menardii. ranged from about 70,000 to about 11,000 years ago Using paleoclimatic estimates based on the (Emiliani, 1955a; Rosholt and others, 1961). There is relative abundances of Globorotalia menardii, no ambiguity on this point in Flint's writings (cf. also Ericson and others (1961, Fig. 24) proposed a Flint and Brandtner, 1961).

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Zeuner (1959). However, all micropaleonto- eastern Mediterranean core 189, Parker (1959) logical parameters discussed above, theO18/O16 considered entire foraminiferal assemblages measurements, and the weight percentages of together with their ecological relationships, the sediment fraction larger than 62 n clearly and obtained temperature estimates which she and consistently indicate that stage 5 was a judged to be in striking agreement with the warm stage with a temperature maximum at isotopic temperatures previously published by least as high as that of the postglacial, and Emiliani (1955b). possibly slightly higher (cf. the occurrence of Globigerinoides rubra rubra in the eastern CONCLUSION Mediterranean core 189: Emiliani, 1955b). A tentative extension of the generalized Thus, stage 5 cannot represent a temperate temperature curve previously published, is episode within a glaciation, but must represent yielded by O18/O16 analysis of cores A254- an interglacial as full as the present one. While BR-C and CP-28 from the Caribbean. An the correlations proposed by Ericson and early temperature minimum, dating from an Wollin (1956a; 1956b), Ericson and others estimated age of 315,000 years ago, is recog- (1961), and Zeuner (1959) are probably in nized. If the estimated age is about correct, error for stage 5 (and earlier stages), the time this minimum would follow a pronounced estimates given by Ericson and others (1961, insolation minimum (321,000 years B.P.) with p. 274 and ff.) are close to those published by the usual delay of a few thousand years. Thus, Emiliani (1955a; 1958) and subsequently veri- the contention that the repeated glaciations fied by Pa231/Th230 dating (Rosholt and others, of the Pleistocene were triggered by insolation 1961; 1962). minima in the high northern latitudes (cf. The preceding discussion clearly indicates Emiliani and Geiss, 1959) receives some addi- that the assumption that the relative abun- tional support. dances of Globorotalia menardii are directly A critical evaluation of the micropaleonto- proportional to temperature is not valid for logical data published by Ericson and Wollin the middle and lower portions of the cores. (1956a; 1956b), Ewing and others (1958), and Consequently, the paleoclimatic reconstruc- Ericson and others (1961), and an analysis of tions based on this assumption (Figs. 6A and these data using more stringent biological and 6B, curves J; Fig. 7, curve A; Ericson and paleonotological criteria, provide a paleo- others, 1961, Fig. 24) are questionable. It is climatological and stratigraphic synopsis which also clear that rather stringent biological, is largely at variance with that proposed by paleontological, and statistical criteria must be the cited authors. This synopsis is supported used to obtain paleoclimatic reconstructions of by the O18/O16 measurements and is in agree- some validity from the complex fossil assem- ment with that proposed by the writer blages contained in the deep-sea cores of (Emiliani, 1955a; 1958; 1961). Globigerina-oo7.e facies. In her study of the

REFERENCES CITED Arrhenius, G., 1952, Sediment cores from the east Pacific: Swedish Deep-Sea Exped. 1947-1948, Repts., v. 5, fasc. 1, 227 p. Be, A. W. H., 1960, Ecology of Recent planktonic Foraminifera; Part 2: Micropaleontologv, v. 6, p. 373-392 Bradshaw, J. S., 1959, Ecology of living planktonic Foraminifera in the North and Equatorial Pacific Ocean: Cushman Found. Foram. Res., Contr., v. 10, p. 25-64 Broecker, W. S., Turekian, K. K., and Heezen, B. C., 1958, The relation of deep-sea sedimentation rates to variations in climate: Am. Jour. Sci., v. 256, p. 503-517 Eardley, A. J., and Gvosdetsky, V., 1960, Analysis of Pleistocene core from Great Salt Lake, Utah- Geol Soc. America Bull., v. 71, p. 1323-1344 Emiliani, C., 1954, Depth habitats of some species of pelagic Foraminifera as indicated by oxygen isotope ratios: Am. Jour. Sci., v. 252, p. 149-158 1955a, Pleistocene temperatures: Jour. Geology, v. 63, p. 538-578 1955b, Pleistocene temperature variations in the Mediterranean: Quaternaria, v. 2, p. 87-98 1957, Temperature and age analysis of deep-sea cores: Science, v. 125, p. 383-387

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Emiliani, C., 1958, Paleotemperature analysis of core 280 and Pleistocene correlations: Jour. Geology, v. 66, p. 264-275 1961, Cenozoic climatic changes as indicated by the stratigraphy and chronology of deep-sea cores of Globigerina-ooze facies: New York Acad. Sci., Annals, v. 95, Art. 1, p. 521-536 Emiliani, C., and Geiss, J., 1959, On glaciations and their causes: Geol. Rundschau, v. 46 (1957), p. 576-601 Emiliani, C., and Mayeda, T., 1961, Carbonate and oxygen isotopic analysis of core 241A: Jour. Geology, v. 69, p. 729-732 Emiliani, C., Mayeda, T., and Selli, R., 1961, Paleotemperature analysis of the Plio-Pleistocene section at Le Castella, Calabria, southern Italy: Geol. Soc. America Bull., p. 679-688 Ericson, D. B., and Wollin, G., 1956a, Correlation of six cores from the equatorial Atlantic and Carib- bean: Deep-Sea Research, v. 3, p. 104-125 1956b, Micropaleontological and isotopic determinations of Pleistocene climates: Micropaleontology, v. 2, p. 257-270 1962, Micropaleontology: Scientific American, v. 207, no. 1, p. 96-106 Ericson, D. B., Ewing, M., Wollin, G., and Heezen, B. C., 1961, Atlantic deep-sea sediment cores: Geol. Soc. America Bull., v. 72, p. 193-286 Ericson, D. B., Wollin, G., and Wollin, J., 1954, Coiling direction of Globorotalia truncatulinoides in deep-sea cores: Deep-Sea Res., v. 2, p. 152-158 Evernden, J. F., Curtis, G. H., and Kistler, R., 1957, Potassium-argon dating of Pleistocene volcanics: Quaternana, v. 4, p. 13-17 Evernden, J. F., Savage, D. E., Curtis, G. H., and James, G. T., 1964, Potassium-argon dates and the Cenozoic mammalian chronology of North America: Am. Jour. Sci., v. 262, p. 145-198 Ewing, M., Ericson, D. B., and Heezen, B. C., 1958, Sediments and topography of the Gulf of Mexico, p. 995-1053 in Weeks, L., Editor, Habitat of oil: Am. Assoc. Petroleum Geologists Flint, R. F., 1957, Glacial and Pleistocene geology: New York, John Wiley & Sons, 553 p. Flint, R. F., and Brandtner, F., 1961, Climatic changes since the last interglacial: Am. Jour. Sci., v. 259, p. 321-328 Jones, J. I., in press, The distribution and variation of living pelagic Foraminifera in the Caribbean Sea: Third Caribbean Geol. Conf. Proc. Kemp, W. C., and Eger, D., in press, On the relationships among sequences, with applications to geological data: Jour. Geology Lona, F., 1950, Contributi alia storia della vegetazione e del clima nella Val Padana. Analisi pollinica del giacimento Vallafranchiano di Leffe (Bergamo): Soc. Ital. Sci. Nat., v. 89, p. 123-178 Lona, F., and Follieri, M,, 1957, Successione pollinica della serie superiore (Giinz-Mindel) di Leffe (Bergamo): Viert. Intern. Tagung d. Quartarbotaniker, Verhandl., Geobotan. Inst. Riibel, Zurich, Heft 34, p. 86-98 Parker, F. L., 1959, Eastern Mediterranean Foraminifera: Swedish Deep-Sea Exped. 1947-1948, Repts., v. 8, fasc. 4, p. 217-283 Phleger, F. B, 1960, Ecology and distribution of Recent Foraminifera: Baltimore, The Johns Hopkins Press, 297 p. Rosholt, J. N., Emiliani, C., Geiss, J., Koczy, F. F., and Wangersky, P. J., 1961, Absolute dating of deep-sea cores by the Pa231/Th230 method: Jour. Geology, v. 69, p. 162-185 1962, Pa231/Th230 dating and O18/O16 temperature analysis of core A254-BR-C: Jour.Geophys. Res., v. 67, p. 2907-2911 1963, Absolute dating of deep-sea cores by the Pa231/Th230 method and accumulation rates: a reply: Jour. Geology, v. 71, p. 810 Rubin, M., and Suess, H. E., 1955, U. S. Geological Survey radiocarbon dates II: Science, v. 121, p. 481-488 1956, U. S. Geological Survey radiocarbon dates III: Science, v. 123, p. 442-448 Rusnak, G. A., 1963, Absolute dating of deep-sea cores by the Pa231/Th230 method and accumulation rates: a discussion: Jour. Geology, v. 71, p. 809-810 Rusnak, G. A., Bowman, A. L., and Ostlund, H. G., 1963, Miami natural radiocarbon measurements II: Radiocarbon, v. 5, p. 23-33 Soergel, W., 1939, Das diluviale System: Berlin, Fortschr. Geol. Pal., v. 39, p. 155-292

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Szafer, W., 1954, Plioceriska flora okolic Czorsztyna i jej stosunek do Plejstocenu: Warsaw, Inst. Geol. PubL, v. 11, 238 p. Venzo, S., 1953, Stadi della glaciazione del Donau sotto al Gunz nella serie lacustre di Leffe (Bergamo- Lombardia): Geologica Bavarica, no. 19, p. 74-93 Woldstedt, P., 1958, Das Eiszeitalter, Volume 2: Stuttgart, Ferdinand Enke, 438 p. Zagwijn, W., 1959, Zur stratigraphischen und pollenanalytischen Gliederung der pliozanen Ablagerungen im Roertal-Graben und Venloer Graben der Niederlande: Geol. Rheinld. u. Westf., Fortschr.,v. 4, p. 5-26 1960, Aspects of the Pliocene and early Pleistocene vegetation in the Netherlands: Geol. Stichting, Mededel., ser. C, III-l, No. 5, 78 p. Zeuner, F. E., 1959, The Pleistocene Period: London, Hutchinson, 447 p.

MANUSCRIPT RECEIVED BY THE SOCIETY, MARCH 11, 1963 CONTRIBUTION No. 517 FROM THE INSTITUTE OF MARINE SCIENCE, UNIVERSITY OF MIAMI, MIAMI, FLA.

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/75/2/129/3427567/i0016-7606-75-2-129.pdf by guest on 01 October 2021 APPENDIX 1. Core A254-BR-C. Oxygen isotopic APPENDIX 3. Core CP-28. Oxygen analyses on analyses on shells of Globigerinoides saccidifera (5 per mil shells of Globigerinoides sacculifera (8 per mil with with respect to the Chicago standard PDB-1) respect to the Chicago standard PDB-1) Depth below 5018 Depth below 5018 Depth below 5O18 Depth below SO18 top (cm) (per mil) top (cm) (per mil) top (cm) (per mil) top (cm) (per mil) 0-1 -1.44 710-711 -1.13 0-1 -1.61 450-451 -0.68 10-11 -1.42 720-721 -0.83 10-11 -1.58 460-461 -0.81 20-21 -1.30 730-731 -0.99 20-21 -0.85 470-471 -0.47 30-31 -1.39 740-741 -1.46 30-31 -0.64 480-481 -0.85 40-41 -0.03 750-751 -0.74 40-41 -0.35 490-491 -1.27 50-51 -0.11 760-761 -1.41 50-51 -0.34 500-501 -1.22 60-61 +0.01 770-771 -1.28 60-61 -0.74 510-511 -1.21 70-71 -0.01 780-781 -1.37 70-71 -0.59 520-521 -1.14 80-81 790-791 -1.40 80-81 -0.78 530-531 -1.15 90-91 -0.79 800-801 -1.57 90-91 -0.53 540-541 -1.25 100-101 -0.34 810-811 100-101 -0.39 550-551 -1.22 110-111 -0.29 820-821 -1.34 110-111 -0.73 560-561 -1.24 120-121 -0.39 830-831 -1.41 120-121 -0.88 570-571 -1.27 130-131 -0.25 840-841 -1.19 130-131 -0.89 580-581 -0.59 140-141 -0.45 850-851 -1.61 140-141 -0.85 590-591 -0.78 150-151 -0.15 860-861 -1.59 150-151 -0.87 600-610 -1.28 160-161 -0.34 870-871 - 1 .28 160-161 -0.44 610-611 -1.38 170-171 -0.15 880-881 -0.84 170-171 - .12 620-621 -1.27 180-181 -0.44 890-891 -0.71 180-181 - .20 630-631 -0.28 190-191 -0.37 900-901 -0.58 190-191 - .22 640-641 -0.07 200-201 910-911 -0.64 200-201 - .40 650-651 -0.16 210-211 -0.85 920-921 -0.81 210-211 - .33 660-661 220-221 -0.86 930-931 -0.55 220-221 -1.36 670-671 -0.30 230-231 -0.85 940-941 -0.52 230-231 -1.34 680-681 -0.74 240-241 -0.97 950-951 -0.76 240-241 -1.47 690-691 -1.21 250-251 -1.04 960-961 -0.83 250-251 - .38 700-701 -0.88 260-261 -1.18 970-971 -1.36 260-261 - .24 710-711 -0.84 270-271 -1.01 980-981 -1.22 270-271 - .19 720-721 -1.09 280-281 -0.88 990-991 -0.97 280-281 - .12 730-731 -1.11 290-291 -0.88 1000-1001 -0.85 290-291 - .44 740-741 -1.12 300-301 -0.87 1010-1011 -0.76 300-301 - .27 750-751 -1.37 310-311 -0.74 1020-1021 -0.80 310-311 - .47 760-761 -0.46 320-321 -0.85 1030-1031 -0.76 320-321 - .79 770-771 -0.27 330-331 -1.16 1040-1041 -0.77 330-331 - .49 780-781 -0.51 340-341 -1.65 1050-1051 -1.05 340-341 -0.65 790-791 -1.03 350-351 -1.52 1060-1061 -1.02 350-351 -0.55 800-801 360-361 -0.13 1070-1071 -1.39 360-361 -0.21 810-811 -0.98 370-371 -0,37 1080-1081 -1.51 370-371 -0.04 820-821 -1.21 380-381 -0.47 1090-1091 -1.24 380-381 -0.22 830-831 -0.99 390-391 -0.91 1100-1101 -1.46 390-391 -0.27 840-841 -1.12 400-401 -1.19 1110-1111 -1.15 400-401 -0.72 850-851 -1.07 410-411 - 1 .35 1120-1121 -1.08 410-411 -0.66 860-861 -1.13 420-421 -0.89 1130-1131 -1.10 420-421 -0.37 870-871 -1.08 430-431 -0.38 1140-1141 -1.00 430-431 -0.51 880-881 440-441 +0.19 1150-1151 -0.76 440-441 -0.53 890-891 -1.05 450-451 +0.28 1160-1161 -0.79 460-461 +0.06 1170-1171 — 0 68 470-471 -0.24 1180-1181 -0.91 480-481 -1.27 1190-1191 -1.00 490-491 -1.22 1200-1201 -1.26 500-501 1210-1211 -1.50 510-511 -1.00 1220-1221 -1.31 APPENDIX 2. Core A254-BR-C. Oxygen isotopic 520-521 -1.26 1230-1231 -1.11 analyses on shells of Globorotalia menardii (5 per mil with 530-531 +0.20 1240-1241 -1.43 respect to the Chicago standard PDB-1) 540-541 +0.27 1250-1251 -1.28 18 18 550-551 -1.41 1260-1261 -1.23 Depth below SO Depth below 5O 560-561 -1.06 1270-1271 - 1 .03 top (cm) (per mil) top (cm) (per mil) 570-571 -1.24 1280-1281 -1.34 780-781 +0.17 910-911 -0.24 580-581 -1.15 1290-1291 -1,37 790-791 +0.02 920-921 -0.18 590-591 -1.18 1300-1301 -1.03 800-801 -0.06 930-931 -0.15 600-601 -1.02 1310-1311 -1.06 810-811 +0.04 940-941 -0.24 610-611 -0.70 1320-1321 -1.10 820-821 -0.04 950-951 -0.25 620-621 -0.85 1330-1331 -1.07 830-831 0.00 960-961 -0.37 630-631 -1.08 1340-1341 -0.88 840-841 +0.08 970-971 -0.31 640-641 -0.76 1350-1351 -1.05 850-851 +0.01 980-981 -0.10 650-651 -0.77 1360-1361 -0.97 860-861 -0.03 990-991 -0.15 660-661 -0.90 1370-1371 -1.28 870-871 +0.08 1000-1001 -0.33 670-671 -1.11 1380-1381 -1.14 880-881 -0.24 1010-1011 -0.13 680-681 -0.85 1390-1391 -1.10 890-891 -0.23 1020-1021 -0.13 690-691 -0.07 1400-1401 -1.14 900-901 -0.14 700-701 -1.06

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