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I. O. Murdmaa G. H. Kazarina L. Beaufort E. V. Ivanova E. M. Emelyanov V. A. Kravtsov G. N. Alekhina V. E. Vasileva 《Lithology and Mineral Resources》2010,45(2):154-171
Core MD02-2508 retrieved from the plateau of the continental slope off Baja California recovered a 40-m-thick section of sapropel
(up to 15% Corg), calcareous clay, and diatom ooze with the age of 120 ka at the core bottom. The section is subdivided into three units:
Unit I (Holocene) consists of the laminated sapropel; Unit II comprising oxygen isotope stages (MIS) 2, 3, and 4 is represented
by homogeneous calcareous clay with interbeds of slightly siliceous sapropelic mud; and Unit III (MIS-5) is composed of laminated
sapropelic diatom ooze. Laminated intervals are characterized by the intercalation of two lamina types: (1) dark-colored organic-rich
laminae containing multi-species “oceanic” diatom assemblages, as well as radiolarians, coccoliths, planktonic and benthic
foraminifera; (2) lighter-colored laminae consisting of diatom ooze with the neritic colonial diatom assemblages commonly
composed of one to three species of a single genera. The dark laminae are assumed to be generated within a high productivity
zone over the slope, whereas light ones likely represent diatom mats produced by short-term boisterous phytoplankton blooms,
possibly in the coastal upwelling. 相似文献