کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8906912 1634664 2018 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A 20-15 ka high-resolution paleomagnetic secular variation record from Black Sea sediments - no evidence for the 'Hilina Pali excursion'?
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
پیش نمایش صفحه اول مقاله
A 20-15 ka high-resolution paleomagnetic secular variation record from Black Sea sediments - no evidence for the 'Hilina Pali excursion'?
چکیده انگلیسی
A comprehensive magnetostratigraphic investigation on sixteen sediment cores from the southeastern Black Sea yielded a very detailed high-quality paleosecular variation (PSV) record spanning from 20 to 15 ka. The age models are based on radiocarbon dating, stratigraphic correlation, and tephrochronology. Further age constraints were obtained by correlating four meltwater events, described from the western Black Sea, ranging in age from about 17 to 15 ka, with maxima in K/Ti ratios, obtained from X-ray fluorescence (XRF) scanning, and minima in S-ratios, reflecting increased hematite content, in the studied cores. Since the sedimentation rates in the investigated time window are up to 50 cm ka−1, the obtained PSVs records enabled a stacking using 50-yr bins. A directional anomaly at 18.5 ka, associated with pronounced swings in inclination and declination, as well as a low in relative paleointensity (rPI), is probably contemporaneous with the Hilina Pali excursion, originally reported from Hawaiian lava flows. However, virtual geomagnetic poles (VGPs) calculated from Black Sea sediments are not located at latitudes lower than 60°N, which denotes normal, though pronounced secular variations. During the postulated Hilina Pali excursion, the VGPs calculated from Black Sea data migrated clockwise only along the coasts of the Arctic Ocean from NE Canada (20.0 ka), via Alaska (18.6 ka) and NE Siberia (18.0 ka) to Svalbard (17.0 ka), then looping clockwise through the Eastern Arctic Ocean.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Earth and Planetary Science Letters - Volume 492, 15 June 2018, Pages 174-185
نویسندگان
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