Keiji Horikawa
 
Ongoing Researches
 
Reconstruction of alkenone-derived sea-surface temperature and nitrogen isotope in the eastern equatorial Pacific over the past 800 kys
 
High-resolution reconstruction of paleoproductivity and nitrogen isotope in the northwestern North Pacific over the past 100 kyrs
 
Areas of Specialization
 
Earth system history, Stable isotope geochemistry, Organic geochemistry, Sedimentology, Paleoclimate and oceanography
 
Education
 
2003-2006; Ph.D. (Earth Science), Hokkaido University, 2006, (M. Minagawa, advisor), Doctoral thesis entitled “Response of nitrogen cycling to climate-related oceanographic changes during the last glacial-interglacial cycle: a contrastive study between the eastern and western equatorial Pacific”
1999-2003; M.Sc (Geology), Chiba University, 2001
1995-1999; B.Sc. (Geology), Chiba University, 1999
 
Employment Records
 
July 2006- Present; Researcher (Center for Advanced Marine Core Research, Kochi University)
Sep 2003-Mar 2006; JSPS Research Fellowships for Young Scientists
Apr 2003-Aug 2003; COE research assistant (Hokkaido University)
 
Publication List
 
(1) Horikawa K, Takano S, Ito M., and Nakano T, 2001, Glacio-eustatic sea-level changes and paleocenographic changes recorded in shelf-deep sea sediments of the Kazusa Group, Quaternary Research of Japan, v. 40, p. 283-290. (in Japanese)
(2) Ito, M. and Horikawa, K., 2001, Millennial- to decadal-scale fluctuation in the paleo-Kuroshio Current documented in the Middle Pleistocene shelf succession on the Boso Peninsula, Japan. Sedimentary Geology, v. 137, p. 1-8.
(3) Horikawa, K. and Ito, M., 2004, Long-term ENSO-like events documented in the Middle Pleistocene shelf successions, Boso Peninsula, Japan. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 203, p. 239-251.
(4) Takano, S. M. Ito, T. Nakano, K. Horikawa, Y. Nakamura, and T. Saito, 2004, Sequence-stratigraphic signatures of hemipelagic siltstones in deep-water successions: the Lower Pleistocene Kiwada and Otadai Formations, Boso Peninsula, Japan, Sedimentary Geology, v. 170, p. 189-206.
(5) Horikawa, K, Minagawa, M., Kato, Y., Murayama, M, and Nagao, S, 2006, N2 fixation variability in the oligotrophic Sulu Sea, western equatorial Pacific region over the past 83 kyr, Journal of Oceanography, v. 62, p. 427–439.
(6) Horikawa, K., Minagawa, M., Murayama, M., Kato, Y, and Asahi, H., 2006, Spatial and temporal sea-surface temperatures in the eastern equatorial Pacific over the past 150 kyr, Geophysical Research Letters, Vol. 33, L13605, doi:10.1029/2006GL025948.
(7) Horikawa, K.,Shigemitsu, M. and Minagawa, M., Paleoceanographic analyses using nitrogen isotopic compositions, 2007, Journal of Oceanography of Japan, 16(5), 375-399. review paper in Japanese.
 
Submitted Papers
 
Horikawa K, Minagawa, M. Kato, Y. Murayama, M., Productivity evolution forced by precessional cycles in the North Equatorial Countercurrent in the eastern equatorial Pacific over the last 150 kyr (submitted to Quaternary Science Reviews)
 
Center for Advanced Marine Core Research,
Kochi University,
B200 Monobe, Nankoku, Kochi, 783-8502 JAPAN