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Miocene semidiurnal tidal rhythmites in Madre de Dios, Peru

, : Miocene semidiurnal tidal rhythmites in Madre de Dios, Peru. Geology (Boulder) 33(3): 177-180

New data from upper Miocene deposits in the Madre de Dios region, southern Peru, allow the delineation of tidal regime for the first time in western Amazonia and provide strong evidence of elevated tidal range and brackish-water influence. The results point out the insufficiency of the current depositional models and support the earlier hypothesis that western Amazonia was also connected to the Paranan Sea during the late Miocene. In this paper we present sedimentological, ichnological, and statistical (Fourier transformation) data from two selected outcrops containing rhythmite successions from an area that is traditionally considered as continental. The sediments are interpreted to represent tide-dominated, inner-middle estuarine deposits. The cyclic rhythmites display semidiurnal cyclicity. The results are significant because (1) they contradict recent interpretations of the area's paleoenvironmental history; (2) the evidence for tidal processes is persuasive; and (3) the delineated tidal regime and range provide a unique insight into the depositional dynamics of a system having many important paleogeographic implications.


DOI: 10.1130/g21102.1

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Pennelli, N.; Chieco-Bianchi, L.; Tridente, G.; Fiore-Donati, L., 1968: Virus particles in bone marrow megakaryocytes and susceptibility of mice to virus-induced leukemia. Bone marrow megakaryocytes from mice injected with Graff i or Passage A Gross viruses were studied by electron microscopy in order to establish a possible correlation between the presence of virus particles and the susceptibility of mice to leukem...

Ivanov G.G., 1984: Hemodynamic changes during long term artificial lung ventilation with positive end pressure expiration in terminal patients. Anesteziologiya i Reanimatologiya (2): 49-51

Palencia, Rl, 1977: Potato activities in Venezuela. Reunion Latinoamericana de Coordinacion de Actividadesde Investigacion y Produccion de Papa: d 53-56

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