A5071446332- Geology and Paleoclimatology Research
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
- Paleontology and Stratigraphy of Fossils
- Isotope Analysis in Ecology
- Geological and Geophysical Studies
- Geological formations and processes
- Marine and environmental studies
- Cephalopods and Marine Biology
- Hydrocarbon exploration and reservoir analysis
- earthquake and tectonic studies
- Evolution and Paleontology Studies
- Marine animal studies overview
- Geological and Geochemical Analysis
- Ichthyology and Marine Biology
- Ocular Surface and Contact Lens
- Morphological variations and asymmetry
- Geological Studies and Exploration
- Geochemistry and Geologic Mapping
- Marine and coastal ecosystems
- Geomagnetism and Paleomagnetism Studies
- Electron and X-Ray Spectroscopy Techniques
- Pleistocene-Era Hominins and Archaeology
- Marine and coastal plant biology
- Ocean Acidification Effects and Responses
Kōchi University
2013-2023
National Museum of Nature and Science
2019-2023
Marine Advanced Technology Education
2016-2018
Topcon (Japan)
2012
Japan Society for the Promotion of Science
2010-2012
Scripps Institution of Oceanography
2009-2012
University of California, San Diego
2009-2012
Kanazawa University
2002-2010
Cambrian Innovation (United States)
2010
Western University
2010
An impact with a dash of volcanism Around the time end-Cretaceous mass extinction that wiped out dinosaurs, there was both bolide and large amount volcanism. Hull et al. ran several temperature simulations based on different volcanic outgassing scenarios compared them records across event. The best model fits to data required most occur before impact. When combined other lines evidence, these models support an impact-driven extinction. However, gases may have played role in shaping rise...
Continental-scale expansion of the East Antarctic Ice Sheet during Eocene-Oligocene Transition (EOT) is one largest non-linear events in Earth's climate history. Declining atmospheric carbon dioxide concentrations and orbital variability triggered glacial strong feedbacks system. Prominent among these was repartitioning biogeochemical cycles between continental shelves deep ocean with falling sea level. Here we present multiple proxies from a shallow shelf location that identify marked...
Abstract Deep-sea benthic ostracod assemblages covering the last 2 Myr were investigated in Integrated Ocean Drilling Program Site U1426 (at 903 m water depth) southern Sea of Japan. Results show that (1) orbital-scale faunal variability has been influenced by eustatic sea-level fluctuations and oxygen (2) secular-scale transitions are likely associated with mid-Brunhes event (MBE, ~0.43 Ma) onset Tsushima Warm Current (TWC, ~1.7 Ma). Krithe , Robertsonites Acanthocythereis three most...
Research Article| May 01, 2015 No place to retreat: Heavy extinction and delayed recovery on a Pacific guyot during the Paleocene–Eocene Thermal Maximum Tatsuhiko Yamaguchi; Yamaguchi 1Center for Advanced Marine Core, Kochi University, B200 Monobe, Nankoku, Kochi, 783-8205, Japan Search other works by this author on: GSW Google Scholar Richard D. Norris 2Scripps Institution of Oceanography, University California–San Diego, 300C Ritter Hall, MS-0244, La Jolla Shore Drive, Jolla, California...
Eocene ostracodes are described from the Japanese Islands for first time. These ostracodes, Iojima Group in southwestern Japan, represented by cosmopolitan and low- to midlatitudinal paleobiogeographic groups as well an endemic group. Based on distributions of selected genera, ostracode fauna has tropical subtropical affinities, affirming links with Tethys Sea. Six species new: Cytheropteron liue, Eopaijenborchella kamiyai, okinoshimaensis, Ambtonia? matsubarai, Paracypris? kuritai,...
The genus Palmoconcha in the family Loxoconchidae of Ostracoda is found Cenozoic sediments from North Pacific. Pacific divided into two morphological groups: One P. parapontica characterized by having a prominent murus along posterodorsal margin. Another laevimarginata group nonprominent murus. Both and groups contain six species including new species, respectively. distributed only northwestern Pacific, whereas occurs both western eastern sides assemblages occupied group, together with...
At least thirty-three ostracode species are reported for the first time from Oligocene Itanoura Formation, Nishisonogi Group. This is also report of ostracodes Japanese Islands. Fifteen samples bearing fossil were grouped into three biofacies (A to C). Three have characteristics as follows: Biofacies A dominated by Acanthocythereis volubilis (Liu) and Eopaijenborchella sinensis (Liu); B Krithe sp. associated with Palmoconcha oujiangensis A. volubilis; C dominantly includes P. oujiangensis....
The ostracode fauna from the middle–upper Eocene Iwaya Formation on Awajishima Island, Hyogo Prefecture, southwestern Japan was studied to reveal a band of faunal spectrum in middle latitudes northwestern Pacific. Based lithofacies and previously reported calcareous nannofossils, molluscs, benthic foraminifers, ostracodes were found have inhabited inner shelf environments. entirely differ Eocene–earliest Oligocene faunas Kyushu, East China Sea, both generic specific composition. difference...
During the Eocene, Hahajima Island of Ogasawara (Bonin) Islands Izu-Mariana Arc in North Pacific was located near present-day position western Micronesia. We identified 17 Eocene ostracode species from island, which are new and likely endemic to this island or West Pacific. These systematically described herein include: Costa matsumarui n. sp., Cytherelloidea ogasawaraensis Havanardia ujiiei Jugosocythereis nishii Neonesidea boninensis Schizocythere antiquimicronesiana Uroleberis...
Abstract Sexual dimorphism is thought to have evolved via selection on both sexes. Ostracodes display sexual shape in adult valves; however, no previous studies addressed temporal changes evolutionary timescales or examined the relationships between and pressure juvenile shape. Temporal sexually dimorphic traits result from responses of these pressure. Using Gaussian mixture model for height/length ratio, a valve-shape parameter, we identified differences valve Krithe dolichodeira s.l....
Abstract Upper Devonian carbonates of the Toc Tat Formation in Si Phai Pass area Dong Van District, northern Vietnam were deposited carbonate platform, slope, and basin environments. These yield abundant conodonts indicative Palmatolepis nasuta , Pa. linguiformis triangularis zones, Frasnian–Famennian stage boundary being identified by first occurrence . Two positive carbon isotope excursions are recognized, lower excursion peaking interval to middle Zone, whilst upper peaks just above local...