https://kyushu-u.elsevierpure.com/en/persons/hiroshi-naraoka
　Reseacher Profiling Tool　Kyushu University Pure

http://www.planetaryorganics.jp/english.html
Laboratory for Planetray Trace Organic Compounds .

http://orge.geo.kyushu-u.ac.jp/HN/English.html
Homepage in English (Research and Teaching) .

Doctor of Science

No

Organic Cosmogeochemistry

0000-0002-2373-8759

01years01months

The Earth environment has changed dynamically since its birth. In particular, biological activities have important roles on the evolution of the Earth's surface environment. In order to understand better the environmental changes and associated biological acitivities, we should study geochemical cycles of elements and molecules that operate in Earth's surface system over different periods of time. Furthermore, origin of life on the Earth is the most challenging issue in science. Past biological activities as well as chemical evolution prior to life should be studied by organic compounds in rocks (chemical fossils known as biomarkers) as well as extraterrestrial materials such as meteorites. My recent research projects include: 1) characterization of organic matter in carbonaceous chondrites; 2) chemical and isotopic studies of sedimentary organic matters from Archean to present to clarify biological activities associated closely with Earth’s surface changes; 3) multi-isotope studies of biomarkers in deep-sea drilling samples as well as hydrothermal environments to investigate bacterial communities with their metabolisms; 4) modern geochemical cycles of organic matter in terrestrial-marine systems including isotopic characterization of bioorganic compounds; 5) laboratory simulation in formation and isotope fractionation of organic compounds; and 6) development of molecular and isotopic analytical techniques for trace amounts of organic matter in natural samples.

Research Interests

• 1. Chemical evolution of organic compounds in extraterrestrial materials
  2. Origins of life on the earth and the evolution of the biosphere
  3. Biogeochemistry of sediments and sedimentary rocks, and biogeochemical cycles on the earth
  4. Stable isotope geochemistry of organic compounds in natural environments
  keyword : Chemical evolution, Meteorite, Origins of life, Organic compound, Biomarker, Lifes in extreme environments, Stable isotopes
  2000.04～2025.03.

Academic Activities
Membership in Academic Society

• The Geochemical Society of Japan
• The Japanese Association of Organic Geochemists
• The Japanese Society for Planetary Sciences
• The Meteoritical Society