Iridium profiles and delivery across the Cretaceous/Paleogene boundary
نویسندگان
چکیده
منابع مشابه
a comparative pragmatic analysis of the speech act of “disagreement” across english and persian
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15 صفحه اولd13C depth profiles from paleosols across the Permian-Triassic boundary: Evidence for methane release
Stable carbon isotopic analyses of organic carbon (d13C) in individual paleosol profiles from Permian–Triassic sequences of Antarctica reveal systematic isotopic variations with profile depth. These variations are in many cases analogous to those in modern soils, which are functions of redox conditions, soil development, and degree and type of microbial decay. In modern soils, these isotopic de...
متن کاملTHE PRISTINE CHICXULUB EJECTA SEQUENCE AT ODP Leg 207: A MICRO-CHEMICAL STUDY
Introduction: The discovery of high concentrations of platinum group elements (PGEs) in the uppermost clay-rich sediments of the Cretaceous (K) was the key to link the mass extinction at the CretaceousPaleogene (“K/T”) boundary to the impact of a large extraterrestrial projectile, now known to have formed the Chicxulub crater [1]. The true nature of this “Iridium anomaly” as well as of other st...
متن کاملthe effect of item modality, note-taking and input source on iranian upper-intermediate efl learners listening comprehension across gender
نقش مهم آزمون مهارت شنیداری در آموزش زبان نیازمند آنست که محققان مطالعاتی را در زمینه عوامل موثر بر عملکرد زبان آموزان انجام دهند. به همین منظور، تحقیق حاضر برآن بوده که تاثیر عواملی چون نوع ارائه سوال، نوت برداری و بومی یا غیر بومی بودن گوینده را بر عملکرد زبان آموزان ایرانی مقطع پیشرفته در آزمون مهارت شنیداری بررسی نماید. در همین راستا و برای بررسی هریک از عوامل ذکر شده، یک آزمون شامل 20 سوال...
diversity changes among calcareous nannofossil assemblages across the paleocene – eocene boundary in the zagros (southwest iran)
calcareous nannofossil assemblages of the boundary paleocene-eocene deposits (pabdeh formation) of the zagros, dezful embayment-mansouri oilfield have been studied in detail. it consists of shale and grey marlstone with inter layers of calcareous argillites and marly claystone. we present a study focused on changes in calcareous nannofossils of the pabdeh formation during the paleocene/eocene b...
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ژورنال
عنوان ژورنال: Earth and Planetary Science Letters
سال: 2017
ISSN: 0012-821X
DOI: 10.1016/j.epsl.2016.10.010