eltanin sedimentary cores and dredged rocksan examination of the eltanin-dredged rocks from the...

Acknowledgement. These investigations have beensupported by the National Science Foundation undergrant GA-4001 to Dr. H. G. Goodell.

ReferencesCohen, C. L. D. 1964. Coccolithophorids from two Carib-

bean deep-sea cores. Micropaleontology, 10(2) : 231-250.Geitzenauer, K. R. 1969. Coccoliths as Late Quaternary

paleoclimatic indicators in the subantarctic Pacific Ocean.Nature, 223: 170-172.

Hay, W. W., H. P. Mohler, P. H. Roth, R. R. Schmidt, andJ . E. Boudreaux. 1967. Calcareous nannoplankton zona-tion of the Cenozoic of the Gulf Coast and Caribbean-Antillean area and transoceanic correlation. Gulf CoastAssociation of Geological Societies. Transactions, 17:428-480.

Hays, J. E. 1967. Quaternary sediments of the AntarcticOcean. Progress in Oceanography, 4: 117-131.

Kennett, J. P. In press. Pleistocene paleoclimates andforaminiferal biostratigraphy in subantarctic deep-seacores. Deep-Sea Research.

McIntyre, A. 1967. Coccoliths as paleoclimatic indicatorsof Pleistocene glaciation. Science, 158: 1314-1317.

Continuing Studies of EltaninSedimentary Cores and Dredged Rocks

N. D. WATKINS

Department of GeologyThe Florida State University

In a previous report (Watkins, 1960), mention wasmade of paleomagnetic observations of some Eltaninsedimentary cores indicating hitherto undiscoveredshort-period reversals of the earth's magnetic field 0.82and 1.07 million years ago. Subsequent detailed exam-ination of cores taken during Cruises 27 through 35have confirmed this earlier suggestion. Fig. 1 showsthe results of studies made on one of these cores. Thedata are to be presented at a meeting of the Interna-tional Association of Geoinagnetisrn and Aeronomy inMadrid in September, 1969.

During 1969, the paleoniagnetic investigations havebecome integrated with the micropaleontologicalstudies of Dr. J . Kennett. It appears probable that thepaleo-oceanographic history of the area south of Aus-tralia and New Zealand will become clearer throughthe current application of these two disciplines to thesediment cores taken during Eltanin Cruises 16, 26,27, 34, and 35.

The distribution of the dredged rocks recoveredduring Eltanin Cruises 5-9, 12, and 22 in the ScotiaSea has been examined. It has been shown that theAntarctic Continent south of the Weddell Sea and theeast coast of the Antarctic Peninsula are probably themajor sources of the recovered materials (Watkinsand Self, 1969). Since an earlier regional survey ofthe Eltanin dredges from the Pacific (Watkins

CORE32-47TREATMENT 150 CE.

INCLINATION, DECREES

mom000

Figure 1. Inclination of remanent magnetism in specimens ofcore E32-47, following demagnetization at 150 oersteds. Polaritylog at right; black is normal polarity (negative or upward mag-netic inclination), clear is reversed (positive or downward mag-netic inclination). Specimen interval 10 cm. The known polaritytime scale is to the right. Added to this are the two short polarityevents initially detected by examination of cores from earlierEltanin cruise (Watkins, 1968). Correlation lines are included.

et at., 1968) indicated that rocks recovered duringCruises 16, 26, and 27 over the Macquarie Rise in-cluded some in situ materials, chemical, petrological,and magnetic analyses have been made of several ofthe samples, in conjunction with Dr. B. M. Gunn,University of Montreal. This research has revealedthe occurrence of hartzburgites, of high intensity ofmagnetization, which may be relevant to the genesisof the Rise. Further analyses are intended before thedata are published.

References

Watkins, N. D. 1968. Short period geomagnetic polarityevents in deep-sea sedimentary cores. Earth and Plane-tary Science Letters, 4: 341-349.

Watkins, N. D. and R. Self. 1969. An examination of theEltanin-dredged rocks from the Scotia Sea. Submittedto Antarctic Research Series.

Watkins, N. D., R. Self, N. Mark, and H. G. Goodell. 1968.A description of the Eltanin-dredged submarine rocksfrom the South Pacific and Scotia Seas. American Geo-physical Union. Transactions, 49: 214.

The Antarctic Marine Geology ResearchFacility

H. G. GOODELL and DENNIS S. CASSIDY

Departments of Oceanography and GeologyThe Florida State University

Cores obtained during USNS Eltanin cruises arestored in 5,200 ft 2 of refrigerated storage at 2°C.,the temperature of Antarctic Bottom Water, in theAntarctic Marine Geology Research Facility of Flo-rida State University. An additional 400 ft 2 is refrig-erated to —10°C. for storage of core cuts destined for

DEPTH, CH

RM

September—October 1969 177

IiI:I a?r4 a

\

Figure 1. Split piston cores from USNS Eltanin stored at 2 C C. atthe Antarctic Marine Geology Research Facility at Florida State

University.

analysis of organic geochemistry, and 5,000 ft 2 is de-voted to core and sample processing.

The Facility was completed in January 1966, andcores from Cruise 21 of Eltanin were the first to beacco iii riodated directly. At present, 650 Eltanin cores,totaling more than 4.27 km of sediment, are shelvedon about 20 percent of the available storage (Fig. 1).These cores, from Eltanin Cruises 2-36, representsamples froiti about one-third of the geographic areacovered by the southern oceans.

The 3-11 core sections in their plastic core-linertubes are shipped under refrigeration when possible tothe Facility from the Eltanin port of debarkation inNew Zealand or Australia. At the Facility, the linersare cut through and the cores parted (using a nylonfilament, tagged, and described. A 70-mm contin-uous negative is made of each core prior to initialsa1ui)ling. The core halves are stored in their linerssheathed in a plastic sleeve.

Since the inception of the marine geology programon Eltanin, 14,771 samples have been distributed forsect line n to] ogical, mineralogical, geochemical, and pa-leontological investigations. In addition, 30,819 sam-ples have been taken for paleomagnetic determina-

tions. These samples have gone to 43 investigatorsrepresenting 16 institutions in the U.S.A. Other sam-ples have gone to researchers in Great Britain, France,Monaco, New Zealand, and Australia.

The inventory of Eltanin dredge haul samples, ex-clusive of manganese nodules, has been transferred tothe Smithsonian Oceanographic Sorting Center. Priorto this transfer, 525 samples from the collection hadbeen provided to investigators for study.

Acknowledgement. The Antarctic Marine GeologyResearch Facility is supported by the National Sci-ence Foundation under grant GA-4001 and contractC-564.

Foraminiferal Studies ofSouthern Ocean Deep-Sea Cores

JAMES P. KENNETT

Department of GeologyThe Florida State University

The principal objectives of foraminiferal studies ofsouthern ocean deep-sea cores at Florida State Univer-sity are to establish a foraminiferal biostratigraphyand paleoclimatic history of antarctic, subantarctic,and southern subtropical areas for as much timewithin the Cenozoic as the material allows.

Middle and Upper Pleistocene cores from the sub-antarctic region of the South Pacific (Kennett,1969a) can be divided into three faunal zones on thebasis of the upward sequential appearance of plank-tonic Foraminifera. Correlation of this sequence withestablished radiolarian zones and palcomnagnetic stra-tigraphy are supported by radiomnetric dates. Alterna-tions of cold- and warm-water planktonic foraminif-eral faunas delimit 8 intervals of climatic warmingduring the last 1.2-1.3 mn.y. B.P. The relative magni-tudes of climatic warmings were considerably greaterduring the last 0.5 my. than between 0.5 and 1.2-1.3my. B.P., when conditions were generally cooler.Only once were conditions significantly wanner thanthe Recent, i.e., during the interval between 0.4 and0.5 ni.y. B.P. Paleoclimnatic trends for polar areas canbe correlated rather closely with those of tropicalareas (Ericson and Wollin, 1968)

A South Pacific subtropical core (Eltanin 21-5;36 0 41'S. 93 0 38'W.; length 480 cm), which has beenshown by nannofossils to be Upper Pliocene to LowerPleistocene in age, is significant in showing alterna-tions of dominantly keeled and non-keeled populationsof the Globorotalia truncatulinoides—G. tosaensisplexus (Kennett and Geitzenauer, 1969). The lower(425-480 cm) and upper (0-130 cmii) core sectionscontain populations dominated (> 78 %) by keeled

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