[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

Sediment distribution pattern of the South Caspian Sea: possible hydroclimatic implications

اعتبار موردنیاز: 1
تعداد صفحات: 16 صفحه (637-653)
زبان: en
منتشر شده در: Canadian Journal of Earth Sciences
دوره: 56
شماره:6
سال انتشار: 2019
نوع این مطلب: journal-article
سازمان ناشر: Canadian Science Publishing
کد DOI مقاله: 10.1139/cjes-2017-0239
لینک اطلاعات کامل مقاله: http://dx.doi.org/10.1139/cjes-2017-0239
نویسندگان مقاله: H.A.K. Lahijani , H. Abbasian , A. Naderi Beni , S.A.G. Leroy , S. Haghani , P. Habibi , M. Hosseindust , S. Shahkarami , S. Yeganeh , Z. Zandinasab , V. Tavakoli , F. Vahabi-Asil , J. Azizpour , M. Sayed-Valizadeh , M. Pourkerman , M. Shah-Hosseini
توجه: قبل از اقدام به دریافت مقالات ISI، حتما از تعداد صفحات و نوع مطلب اطمینان حاصل نمایید. با استفاده از لینک اطلاعات فوق، می توانید به صفحه اطلاعات این مقاله در سایت ناشر مراجعه نمایید و تعداد صفحات و... را به دقت کنترل فرمایید. پس از اطمینان به این صفحه بازگشته و مراحل خرید و دریافت فایل مقاله را انجام دهید.
برخی از مقالات رایگان می باشند و بدون خرید از سیویلیکا با کلیک بر روی لینک فوق، از طریق سایت ناشر قابل دریافت می باشند.

چکیده:

The south Caspian subbasin extends from the foot of the Alborz Mountains to the deepest part of Caspian Sea. The lithological background and tectonic setting of the study area primarily control the deposition of thick sedimentary sequences of the basin, while hydroclimatic processes exert secondary impacts on the sediment distribution pattern. To evaluate past hydroclimatic changes, short sediment cores were retrieved from the continental shelf and upper slope of the south Caspian Sea and were treated for basic sedimentological properties and mineralogy. The results show that the sediments are composed of terrigenous, biogenic, and chemical components. The chemical component has a significant signature in the internal structure of the sediment, which reflects degradation of organic material due to a succession of aerobic and anaerobic conditions. Aerobic conditions reflect the extreme climatic conditions that lead to formation of well-oxygenated deep water in lowstands and extremely cold winters, when dense oxygenated water is allowed to touch the bottom sediments. The sediment distribution pattern demonstrates three distinctive areas in the southern continental margin with different organic matter and carbonate content. Fluvial inputs and wave hydrodynamics control the sediment properties and their distribution pattern in the upper shelf, while in deeper parts, the dynamics of water stratification and its temporal and long-term variations, relating to climate and water level changes, determine sediment composition. Overall, the sedimentary distribution pattern is a result of their sources in the catchment basin and the hydroclimate of the Caspian Sea.