Перегляд за Автор "Mudie, Petra J."

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  • Ескіз
    Документ
    Holocene marine transgression in the Black Sea: New evidence from the northwestern Black Sea shelf
    (Elsevier, 2014) Yanko-Hombach, Valentyna V.; Mudie, Petra J.; Kadurin, Serhii V.; Larchenkov, Yevhenii P.; Янко-Хомбах, Валентина Венедиктовна; Янко-Хомбах, Валентина Венедиктівна; Муди, Петра Дж.; Муді, Петра Дж.; Кадурін, Сергій Володимирович; Кадурин, Сергей Владимирович; Ларченков, Євген Павлович; Ларченков, Евгений Павлович
    For two decades, the timing and rate of Holocene marine transgression and the level of the Black Sea prior to the transgression has been the focus of many geological, palaeoecological and archaeological studies. The potential importance of confirming or rejecting the catastrophic flood hypothesis by refining the chronology of the marine transgression and determining the water level of the early Holocene Black Sea (Neoeuxinian) lake is the aim of many ongoing Black Sea palaeoecological studies. In this report we review previous studies and present new data on the early Holocene marine transgression obtained from multidisciplinary studies of several cores from different parts of the Black Sea. Core 342 from the edge of the Dniester paleovalley on NW shelf is particularly important because it provides wood and leaf material from several peat and muddy peat beds, each up to 10 cm thick, interlayered in a coastal succession with mud, clay, and shell coquina. AMS ages for wood fragments and sedge leaves in the peat layers provide critical new data for calibrating and “re-tuning” of previously published shell and bulk detrital peat ages. Our multi-disciplinary study of geological material recovered from different shelf areas of the Black Sea refines the chronology of the marine transgression and clarifies conflicting interpretations of the water level and salinity of the Neoeuxinian lake prior to the initial Mediterranean inflow (IMI) and transgression of Mediterranean water in the Holocene, We find that: (1) The level of the Late Neoeuxinan lake prior to the early Holocene Mediterranean transgression stood around -40 m bsl but not -100 m or more as suggested by advocates of catastrophic/rapid/prominent flooding of the Black Sea by Mediterranean water. (2) At all times, the Neoeuxinan lake was brackish with salinity not less that 7 psu. (3) By 8.9 ka BP, the Black Sea shelf was already submerged by the Mediterranean transgression. An increase in salinity took place over 3600 years, with rate of the marine water incursion being estimated in the order of 0.05 cme1.7 cm a(-1). (4) The combined data set of sedimentological characteristics and microfossil data establish that the Holocene marine transgression was of a gradual, progressive nature in the early Holocene.
  • Ескіз
    Документ
    Microforaminiferal linings as a proxy for paleodelta nd paleosalinity analysis: Danube delta example
    (2017) Mudie, Petra J.; Yanko-Hombach, Valentyna V.; Янко-Хомбах, Валентина Венедиктовна; Янко-Хомбах, Валентина Венедиктівна; Муди, Петра Дж.; Муді, Петра Дж.
    Microforaminiferal linings are the acid-resistant, chitin-like linings of small (<150 μm) foraminiferal tests that are recovered in organic residues after palynological processing of sediments or acid treatment of rock samples. These palynomorphs are considered reliable indicators of brackish and marine paleoenvironments, and they are a proxy for foraminiferal production when carbonate preservation is reduced (Mathison and Chmura, 1995). Presence or absence of microforaminiferal (abbrev. microforam) linings is an important criterion used in palynofacies models to distinguish the transition from coastal lakes across delta front, prodelta, and shelf sub-environments.
  • Ескіз
    Документ
    New evidence from the Northwestern Shelf for holocene marine transgression of Northwestern Black Sea
    (LTD "Sachino", 2013) Yanko-Hombach, Valentyna V.; Mudie, Petra J.; Kadurin, Serhii V.; Larchenkov, Yevhenii P.; Янко-Хомбах, Валентина Венедиктовна; Янко-Хомбах, Валентина Венедиктівна; Муди, Петра Дж.; Муді, Петра Дж.; Кадурин, Сергей Владимирович; Кадурін, Сергій Володимирович; Ларченков, Евгений Павлович; Ларченков, Євген Павлович
    For two decades, the timing and rate of Holocene marine transgression and the level of the Black Sea prior to the transgression has been the focus of many geological, paleoecological, and archaeological studies. The potential importance of confirming or rejecting the catastrophic flood hypothesis by refining the chronology of the marine transgression and determining the water level of the early Ilolocene Black Sea (Neoeuxinian) lake is the aim of many ongoing Black Sea paleoecological studies. In a new study, we undertook to review a vast array of previous geological and paleoecological studies, including the original sites of Ryan et al. (1997) which were used to hypothesize a catastrophic Holocene flood, and we have obtained new data on the onset and rate of the early Holocene marine transgression using multidisciplinary studies of 19 cores from different parts of the Black Sea.