• OLR (1987) 34 (1 I) D. Submarine Geology and Geophysics 959

87:6301 Polyakov, Ye.V., 1986. Calculation of the tidal

evolution of the Earth-Moon system based on a numerical model of tides in the paleoocean, lzv. Atmos. Ocean Phys. (a translation of Fiz. Atmos. Okeana), 22(5):383-388.

Over the Phanerozoic, the value for L, tidal force moment in the paleoocean with an elastic bottom, and -E, the tidal energy dissipation rate, have changed nonmonotonically, and for a long time their values remained several times less than those at present. The variation of -E as a function of astronomical and geodynamic factors has been analyzed by numerical experiments. The important influence of the latter on the evolution of the Earth-Moon system, is explained by a relationship between the configuration of the ocean and its resonant properties. Inst. of Oceanol., Acad. of Sci., USSR.

87:6302 Ran, G.H., M.A. Arthur and W.E. Dean, 1987.

ISN/14N variations in Cretaceous Atlantic sedi- mentary seqnenees: implication for past changes in marine nitrogen biogenehemistry. Earth planet. Sci. Letts, 82(3-4):269-279.

At DSDP sites 367 and 530 Early to Middle Cretaceous organic-carbon-rich 'black shales' were found to have significantly lower 8~5N values than adjacent carbon-poor white limestones or green claystones, other marine sediments, and most con- temporary marine nitrogen pools. In contrast, black, organic-carbon-rich beds at DSDP Site 603 contain terrestrial organic matter with C- and N-isotopic compositions similar to organic matter of modern terrestrial origin. The recurring ~SN depletions in marine-derived Cretaceous sequences prove that the nitrogen is the result of episodic, atypical bioge- ochemistry. Reduced ocean circulation, increased denitrifieation, and, hence, reduced euphotic zone nitrate availability may have led to Cretaceous phytoplankton assemblages periodically dominated by N2-fixing blue-green algae, a possible source of this marine sediment ~SN-depletion. Inst. of Mar. Sci., Univ. of Calif., Santa Cruz, CA 95064, USA.

87:6303 Sahagian, Dork, 1987. Epeirogeny and eustatic sea

level changes as inferred from Cretaceous shore- line deposits. Applications to the central and western United States. J. geophys. Res., 92(B6): 4895-4904.

Sediments deposited at or near sea level provide a worldwide datum against which to measure post- depositional epeirogenic movements. The present

elevations of epicontinental shoreline sediments deposited during past highstands define a warped surface documenting subsequent epeirogeny of continental interiors. When the amplitude of sea level rise during transgression is small relative to observed epeirogenic motions, the diachronous shoreline deposits can be used as a datum, aug- menting available data and areal coverage. If a 'stable' frame of reference can be defined, a eustatic sea level correction can be applied to every conti- nent. The elevation of the upper Cenomanian shoreline gives little evidence of warping or uplift in central cratonic North America but indicates that a large area of the western U.S. has undergone more than 2 km post-Cenomanian epeirogenic uplift. Dept. of the Geophysical Sci., Univ. of Chicago, 5734 S Ellis Ave., Chicago, IL 60637, USA.

87:6304 Scott, D.B., F.S. Medioli and A.A.L. Miller, 1987.

Holocene sea levels, paleoceanography, and late glacial ice configuration near the Northumberland Strait, Maritime Provinces. Can. J. Earth Sci., 24(4):668-675. Centre for Mar. Geol., Dalhousie Univ., Halifax, NS B3H 3J5, Canada.

87:6305 Seslavinskiy, K.B., 1986. Tectonic evolution of the

continents during Early and Middle Paleozoic time. Int. Geol. Rev., 28(7):751-764.

Data compiled from the Atlas of Lithological- Paleogeographic Maps of the World (Ronov et al., 1984) are used to construct a chronology of Early- Middle Paleozoic global changes in sedimentation rates, volcanism, and tectonism. The period of time analyzed is part of the geosynclinal-platformal phase of crustal evolution, which began about 1400 mya for Laurasia and 600 mya for Gondwana. During each of the orogenic cycles for this period-- the Caledonian, Hercynian, and Alpine orogenies-- the overall area of the continents increased an average of 15%. The late Riphean, Late Cambrian- Middle Ordovician, and Early-Late Devonian, which coincide with global tectonic cycles, were intervals of significant destruction. The author finds no evidence for an increase in sedimentation rate between the Vendian and Cenozoic. Vernadskiy Inst. of Geochem. and Analytical Chem., Acad. of Sci., Moscow, USSR. (hbf)

87:6306 Sokolov, S.D., 1987. Exotic bodies of Early Mesozoic

age in the northern part of the circum-Pacific belt. Dokl. Earth Sci. Sect. (a translation of Dokl. Akad. Nauk SSSR), 283(1-6):68-70.

960 D. Submarine Geology and Geophysics OLR (1987) 34 (11) "

Triassic deposits, distinguished by the presence of large, exotic limestone blocks formed by subaqueous slumping are described for occurrences in the Koryak Mountains, the Canadian Cordillera, and elsewhere. Analysis of available data shows that the exotic bodies accumulated in basins with an oceanic crust fairly remote from continental source areas. The exotic material must have been derived from inner-basin carbonate rises with a volcanic base- ment. The presence of Paleozoic and Triassic elastic chert beds in these sections shows that tectonic movements were active throughout the region. It is concluded that the formation of the exotic bodies should be attributed to destructive processes of a new type in regions with an oceanic crust. Geolog. Inst., Acad. of Sei., Moscow, USSR.

87:6307 Tiwari, R.K., 1987. Higher-order eccentricity cycles

of the Middle and Late Miocene climatic varia- tions. Nature, Lond., 327(6119):219-221.

Recent spectral analyses of non-glacial climatic records of the Mid-Cretaceous and Early Mesozoic exhibit the dominance of 100- and 400-kyr eccen- tricity cycles and exclude the possibility that the above periodicities originate from the internal variability of ice sheets. Walsh spectrum analyses of 10 Myr oxygen (6z80) and carbonate (813C) isotope variations (Mid and Late Miocene) reveal statis- tically significant periodicities of ca. 2.0 and 1.25 Myr, 800, 400, 115 and 93 kyr and harmonies of the higher-order terms with remarkable resolution. Higher-order periodicities, hitherto unexplained in the spectrum of deep-sea records, match quite well with predicted large eccentricity cycles in the Earth's orbital variations, indicating that eccentricity forcing (induced by orbital variations) exerts a major influence on the Earth's climate. Inst. fur Geophysik, Olshausenstr 40-60, Christian Albrechts Univ., 23 Kiel, FRG.

D I S 0 . P a l e o n t o l o g y (see also E-BIOLOGICAL OCEANOGRAPHY)

87:6308 Amieux, Pascal, 1987. Petrographic description of

Foraminifera by combination of natural light and cathodoluminescent pictures. C. r. Acad. Sci., Paris, (S6r. II)304(13):741-744. (In French, English abstract.)

A new petrographic method is described for the analysis of mierofauna in thin section. Study of natural light and cathodolumineseent pictures of Ophthalmidium sp. shows that the levels of obser-

vation are at different depths of the same thin section. Comparison of these pictures yields data valuable for determination of partially reerystallized microfauna. Univ. de Geneve, Dept. de Geol. et de Paleontol., 13, rue des Maraichers, 1211 Geneva 4, Switzerland.

87:6309 Belford, D.J., 1983. Note on costellate planktonic

Foraminifera, and the generic designation of Late Cretaceous forms from Western Australia. BMR Bull., Australia, 217:1-10.

87:6310 Chaproniere, G.C.H., 1983. Tertiary larger forami-

niferids from the northwestern margin of the Queensland Plateau, Australia. BMR Bull, Aus- tralia, 217:31-57.

Sixteen species of larger foraminiferids (those with complicated internal structures) have been recorded from four localities. The assemblages are from Tertiary a 3 (early Middle Eocene), Tertiary lower e, and Tertiary upper e (Late Oligocene to Early Miocene). This represents the first record of Tertiary a3 from Australia. The Tertiary upper e assemblage is a new one for this region; one species, Sherbornina carteri, is described as new.

87:6311 Cronin, T.M., 1987. Evolution, biogeography, and

systematic, of Pm'/ana: evolution and spociation in Ostracoda, III. Mere. paleont. Soc, 21:71pp.

A study of Puriana specimens from the eastern Pacific, western Atlantic, Gulf of Mexico. and Caribbean, using original measurements, statistical analyses, and scanning electron photomicrographs from an earlier study, demonstrates that distinct evolutionary responses to the introduction of land and deep water barriers and climate change occurred within Neogene and Quaternary species. Although the isolation of large populations by the elevation of the Isthmus of Panama did not result in lineage splitting, the isolation of small populations on Caribbean islands did in many cases lead to the evolution of new species or subspecies. The study provides specific examples of speciation by clado- genesis and supports a model of evolution driven by abiotic factors in the environment. USGS, 970 Natl. Center, Reston, VA 22092, USA. (hbf)

87:6312 Mateu, Guillermo and Magdalena Gaza, 1986.

Foraminifera and coceolithophores associated with Corallium rubmm (L.). Systematics, ecology and paleoceanographie evolution. Boln Inst. esp. Oceanogr., 3(4):13-52. (In Spanish, English ab-