Vertical Flux of Sedimentary Radiolaria PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Vertical Flux of Sedimentary Radiolaria PDF full book. Access full book title Vertical Flux of Sedimentary Radiolaria by Kozo Takahashi. Download full books in PDF and EPUB format.
Author: Kozo Takahashi
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 111
Get Book Here
Book Description
Author: Kozo Takahashi
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 111
Get Book Here
Book Description
Author: Kozo Takahashi
Publisher:
ISBN:
Category : Marine sediments
Languages : en
Pages : 562
Get Book Here
Book Description
Radiolarians which settle through the oceanic water column were recovered from three stations (western Tropical Atlantic-Station E, central Tropical Pacific-P1 and Panama Basin-PB) using PARFLUX sediment traps in moored arrays at several depths. The taxonomic diversities of the radiolarian assemblages in the sediment traps were very high. A total of 420 taxa, including 23 newly identified taxa, were found at the three stations; of these, 208 taxa were found at station E. The polycystine radiolarians generally reach the sea floor with little change in abundance or species composition, although slight skeletal dissolution occurs throughout their descent. The phaeodarian radiolarians, on the other hand, are largely dissolved within the water column; only a few species reach the sea-floor and these dissolve rapidly at the sediment-water interface. Most radiolarian skeletons sink as individuals through deep water columns without being incorporated into large biogenic aggregates. Because significant numbers of nassellarian and phaeodarian species are deep-water dwelling forms the diversity index of radiolarians increases with increasing depth in the mesopelagic zone. The vertical flux of the total radiolarians arriving at the trap depths (in x 103 individuals/m2/day) ranged from 16-24 (E), 0.6-17 (Pl), and 29-53 (PB). Of these on the average 25 % and 69 % of the total radiolarian flux is transported by Spumellaria and Nassellaria, respectively, while 5 % is carried by Phaeodaria. The measured SiO2 content of the skeletons averaged 91, 98 and 71 % of measured weight for Spumellaria, Nassellaria and Phaeodaria, respectively. The supply of radiolarian silica (mg SiO 2 /m 2/day) to each trap depth ranged from 2.5-4.0 (E), 0.9-3.2 (P), and 5.7-10.4 (PB). The Radiolaria appear to be a significantly large portion of the SiO2 flux in>63 pm size fraction and thus play an important role in the silica cycle. When the radiolarian fluxes at the three Stations are compared with Holocene radiolarian accumulation rates in the same areas it became apparent that several percent or less of the fluxes are preserved in the sediments in all cases and the rest is dissolved on the sea-floor. Estimated excess Si which is derived from SiO2 dissolution on the sea-floor is fairly small relative to advective Si in the western North Atlantic and thus it appears to be insignificant to show any deviation in a simple mixing curve of deep water masses. Weight, length, width, projected area and volume of 58 radiolarian taxa were measured. The density contrast of radiolarians, relative to seawater, generally falls between 0.01 and 0.5 g/cm33. The sinking speed of 55 radiolarian taxa, measured in the laboratory at 3*C, ranged from 13 to 416 m/day. Despite the wide variety of morphology between the species, sinking speeds were best correlated with weight/shell among all the possible combinations of the examined variables. The estimated residence times of these taxa in the 5 km pelagic water column ranged from 2 weeks to 14 months. Large phaeodarians reached the water-sediment interface relatively quickly and ultimately dissolved on the sea floor. Small-sized taxa dissolved en route during sinking. The standing stock of 26 examined abundant taxa is on the order of 1 to 100 shells/m3 . Total radiolarian standing stock ranges from about 450 shells/m3 at Stations P1 and E to 1200 shells/m 3 at Station PB. The rate of production of total Radiolaria is calculated to be 77 to 225 shells/m 3 /day. The turnover time for these species ranges from several days to one month depending on the species and the assumption of the depth interval used for the estimation.
Author: P. De Wever
Publisher: CRC Press
ISBN: 9789056993368
Category : Science
Languages : en
Pages : 700
Get Book Here
Book Description
Radiolarians in the Sedimentary Record presents the current state of knowledge on fossil radiolarians. The author discusses the record, as well as new integrated taxonomic systems at the family level. The book provides comprehensive coverage of the fossil record of these unicellular organisms. It also discusses their important role in the history of the Earth and their development of the biosphere. This text will prove indispensable for graduate students and researchers in geology, oceanography and earth sciences.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
This thesis work has been supported by the National Science Foundation, Submarine Geology and Geophysics Program, Grant OCE80-l9386 and the Woods Hole Oceanographic Institution Education Office.
Author: Jonathan Aitchison
Publisher: Springer Science & Business Media
ISBN: 3764383445
Category : Science
Languages : en
Pages : 137
Get Book Here
Book Description
Radiolaria are a very diverse marine siliceous microplankton group that have existed at least snice the Cambrian to the recent. This volume gives a representative view of research topics discussed at the 10th International Meeting of Radiolarian Palaeontologists. The articles of this volume cover mainly radiolarian biochronology and radiolarian fauna changes.
Author: Kozo Takahashi
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 314
Get Book Here
Book Description
Author: Orvil Roger Anderson
Publisher: Springer Science & Business Media
ISBN: 1461255368
Category : Science
Languages : en
Pages : 363
Get Book Here
Book Description
The study of marine plankton has traditionally focused on those or ganisms that appeared to have obvious ecological significance in un derstanding the major patterns of biological productivity, trophic relations, community structure, and the dynamic interaction of living things with the physical environment. Not infrequently, this thrust has centered on the apparently most abundant and/or larger members of the plankton community, including significant primary producers such as the diatoms, nonthecate algae, and flagellates, or the major con sumers--copepods, gelatinous metazoa, and other abundant metazoan invertebrates. Consequently, some of the less well recognized but also abundant microzooplankton have been given less attention. The radio laria, although widely studied as fossils by micropaleontologists, have in modem times. This is la been relatively neglected by biologists mentable given their widespread distribution in the oceans, remarkably complex form, and not infrequently localized abundance. Their diver sity of form, encompassing solitary species of microscopic dimensions and colonial species as large as several centimeters or more, challenges us to explain their evolutionary origins, explore their structural-func tional correlates, and comprehend the ecological basis for their wide spread occurrence in all oceans of the world fromihe greatest depth to the surface of the sea. Their intricate and aesthetically pleasing skeletons of enormous variety and fine-detailed design formed from amorphous silica (opaline glass) offer a unique biomineralized product that defies immediate biological explanation.
Author: Hans M. Bolli
Publisher: CUP Archive
ISBN: 9780521367202
Category : Science
Languages : en
Pages : 460
Get Book Here
Book Description
This comprehensive synthesis of our knowledge of the biostratigraphy of marine plankton is the work of an international team of eighteen authors. It covers all the major fossil groups that can be used to date sediments and rocks in the time interval Late Mesozoic to Holocene. Altogether more than 3200 taxa are considered, almost all of which are illustrated and depicted on range charts, making the book a valuable work of reference in the earth sciences. For ease of reference by specialists interested in either calcareous or non-calcareous microfossils, the original work is now divided into two independent volumes. Volume 2 describes siliceous and other non-calcareous microfossils, covering radiolaria, diatoms, silicoflagellates, dinoflagellates and ichthyoliths.
Author: Vladimir P. Kolotov
Publisher: Springer Nature
ISBN: 3031098838
Category : Science
Languages : en
Pages : 660
Get Book Here
Book Description
This book presents 41 selected articles written by leading researchers from the Vernadsky Institute of Geochemistry and Analytical Chemistry, part of the Russian Academy of Sciences. The articles are grouped by the following topics: (1) Geochemistry, (2) Meteoritics, Cosmochemistry, Lunar and Planetary Sciences, (3) Biogeochemistry and Ecology, and (4) Analytical Chemistry, Radiochemistry, and Radioecology. The articles present recent experimental data, theoretical investigations, critical reviews, the results of computer modeling in the above-mentioned fields. Intended to provide a scientific “snapshot” of the institute, the book also includes content on its history, main scientific achievements and current goals, together with detailed descriptions of its 25 laboratories and three museums so as to promote new international collaborations. Given its scope, the book will be of interest to all scientists and graduate students working in the areas of geochemistry, analytical chemistry and radiochemistry, earth and environmental sciences, biogeosciences, meteoritics and planetary science, and to those seeking new collaboration opportunities in these areas in Russia.
Author:
Publisher: Academic Press
ISBN: 0081029098
Category : Science
Languages : en
Pages : 5634
Get Book Here
Book Description
Encyclopedia of Geology, Second Edition presents in six volumes state-of-the-art reviews on the various aspects of geologic research, all of which have moved on considerably since the writing of the first edition. New areas of discussion include extinctions, origins of life, plate tectonics and its influence on faunal provinces, new types of mineral and hydrocarbon deposits, new methods of dating rocks, and geological processes. Users will find this to be a fundamental resource for teachers and students of geology, as well as researchers and non-geology professionals seeking up-to-date reviews of geologic research. Provides a comprehensive and accessible one-stop shop for information on the subject of geology, explaining methodologies and technical jargon used in the field Highlights connections between geology and other physical and biological sciences, tackling research problems that span multiple fields Fills a critical gap of information in a field that has seen significant progress in past years Presents an ideal reference for a wide range of scientists in earth and environmental areas of study
