Showing papers in "Palaeogeography, Palaeoclimatology, Palaeoecology in 1994"

TL;DR: The early stages of the middle Miocene were marked by major short term variations in global climates, East Antarctic Ice Sheet (EAIS) volume, sea level, and deep ocean circulation, including increased production of Southern Component Water as mentioned in this paper.

TL;DR: In this article, structural carbonate in biogenic apatite in the postmortem environment is modeled as a process of watermineral interaction, and closed-and open-system model calculations suggest that δ 13 C is much more resistant to diagenetic modification than δ 18 O. Application of the model to teeth, and carbonate cement in sediments from the Badlands, South Dakota, illustrates that these values represent varying extents of diagenesis.

TL;DR: Low β15N values of Wurmian cave bear bone collagen indicate a strictly vegetarian diet, and negative δ13C values suggest a forested habitat, suggest an influence of a 15N-enriched milk diet during the synthesis of tooth collagen, which is partly formed before weaning.

TL;DR: New data on the vegetational history and Quaternary geology of Amazonia permit an improved reconstruction of past environments in Amazonia during the last glacial period, showing that, in certain areas, savanna-type vegetation and savanna forest had replaced the rain forest during the late Pleniglacial.

TL;DR: The dominant plants of the Late Carboniferous lowland tropics were taxonomically and structurally distinct from those of any later time periods as discussed by the authors, and each of the major plant groups had distinctive architectures and tissue composition.

TL;DR: In this article, a detailed biostratigraphic framework was proposed for the recognition of dinoflagellate zones previously defined in bio-and magnetostratigraphically well-calibrated pelagic sequences from central Italy.

TL;DR: In this paper, sedimentological and palynological data from the Tertiary sediments in the Upper Amazon River area suggest that these sediments are fluvio-lacustrine deposits of Middle to Late Miocene age.

TL;DR: In this article, a multivariate analysis of leaf physiognomy provides the basis for estimating various climatic parameters for angiosperm leaf assemblages, including mean annual temperature, mean range of temperature, and mean annual range of temperatures.

TL;DR: In this article, the authors synthesize new information on surface and bottom water conditions, CCD, biogenic silica accumulation, and paleogeogogo raphy, and reconstruct changes in paleo-ocean circulation within the sea.

TL;DR: In this article, three major Carboniferous sedimentary systems affected by fire are investigated: clastic sedimentary system, using extensive fusain deposits in mid-lower carboniferous, near-shore sediments in Donegal, Ireland; volcanic systems using late Early Carboniferus, volcaniclastic sequences in the Midland Valley of Scotland; and coal and coal-bearing sequences in Upper Carboniferiferous (Westphalian B) of the Pennine Basin, England.

TL;DR: Oxygen isotopic, elemental, and X-ray data were presented for a suite of 24 fossil horse teeth from Nebraska ranging in age from 18.2 to 8.5 Ma, to test the use of δ18O of enamel phosphate (δ18OP04) as a quantitative record of continental climate as mentioned in this paper.

TL;DR: In this article, carbon isotope data from 50 North American horse teeth spanning Eocene to Pleistocene age indicate that savanna grasslands, presumably dominated by C 4 grasses as they are today, first became widespread much later than do horses with high-crowned teeth.

TL;DR: A recent extension of the record to close to the base of the Quaternary from examination of an offshore core provides a broad regional and temporal context for evaluation of the true significance of late quaternary changes as mentioned in this paper.

TL;DR: A detailed analysis of two cores recovered from a swamp in the Southern Bateke Plateaux (Congo) provides information on the botanical history of this region during the last 24,000 yr B.P.

TL;DR: In this paper, the authors used the P/Tr boundary data to provide strong evidence for the development of a largely stagnant, anoxic, stratified ocean, which presumably began to form in the lower Upper Permian and persisted into the Lower Triassic, and for a brief episode of its temporary massive mixing just at the suspected P/tr boundary.

TL;DR: A sediment core, 23.5 m long, was recovered from a water depth of ca. 110 m in Lake Barombi Mbo, a maar crater of the Cameroon volcanic chain this paper.

TL;DR: The 87Sr/86Sr of marine carbonate from Upper Cretaceous strata deposited in the Western Interior Seaway, USA, provides a Sr-isotope curve for Late Cretaged time (Cenomanian-Early Maastrichtian) and is calibrated against the most refined ammonite zonation known for the interval as discussed by the authors.

TL;DR: The distribution of foraminiferal morphological groups has been analyzed in Upper Aalenian-Lower Bajocian black siltstones and mudstones of the Pieniny Klippen Belt, Polish Carpathians as discussed by the authors.

TL;DR: A 200 m long marine pollen record from ODP Site 658 (21°N, 19°W) reveals cyclic fluctuations in vegetation and continental climate in northwestern Africa from 3.7 to 1.7 Ma as mentioned in this paper.

TL;DR: In this article, two meter-scale cycles from the Kimmeridge Clay Formation (cored near Marton, Yorkshire) were studied to understand the factors responsible for (OM) accumulation.

TL;DR: A reconstruction of the palaeoenvironmental and palaeogeographical history of the Caqueta River area (Amazonas Basin, Colombia) indicates that the area was characterized by palm swamps, riparian vegetation and a rather diverse tropical forest.

TL;DR: In this paper, the authors compared the last 140 ka with global changes, as registered in oceanic or ice cores, and with palaeomonsson models, for the purpose of wide spatial and time scales.

TL;DR: An oxygen stable isotope study of molluscan macrofossils from the Tithonian to the Eocene of the James Ross Island and Alexander Island areas, Antarctica, was carried out in conjunction with careful petrographic, minerological and geochemical analyses to assess the state of fossil preservation as mentioned in this paper.

TL;DR: Paleoenvironmental and sedimentological data from Laguna Lejia (23°30′S, 67°42′W, 4325 m) in the high Altiplano of the Chilean Atacama desert indicate that climatic conditions during late-glacial times were significantly wetter than today as mentioned in this paper.

TL;DR: The pre-Holocene sediments may be found in sinkhole lakers or filled sinkholes in the Florida peninsula as mentioned in this paper, which demonstrates linkage between continental and oceanic climate events.

TL;DR: In this article, a multivariate analysis of foliar physiognomy provides accurate (valid) and precise (repeatable) data for nonmarine climates in Beringia during the mid-Miocene thermal maximum, both summers and especially winters were warmer than now.

TL;DR: In the Pyramid Lake subbasin of the United States, tufa mounds have been found to have a horizontal aspect and a vertical aspect, indicating that the lower part formed in a receding lake.

TL;DR: In this article, the authors used the carbon and oxygen isotopic composition of pedogenic carbonates associated with these paleosols to estimate the proportion of C3 (trees, shrubs, and cool growing season grasses) and C4 (warm growing season Grasses) plants once present on the landscape.

TL;DR: In this article, the second largest Cretaceous extinction event coincided with an oceanic anoxic event at the Cenomanian/Turonian (C/T) boundary.

TL;DR: In this paper, biogenic and terrigenous components have been obtained from the interval corresponding to the last 2.6 m.y. of ODP Sites 643 and 644 in order to reconstruct surface and deep water regimes in the Norwegian Sea.