Research Achievements - Original paper -

Mineralogical and geochemical characteristics of the Gudang Handak vein group in the Pongkor Au-Ag deposit, West Java, Indonesia

Syaiful Hilal, Ryohei Takahashi, Jonathan Tandang Macuroy, Andrea Agangi, Pearlyn Manalo, Manuel Nopeia, Hinako Sato, Mega Fatimah Rosana, Abdul Bari, Bayuaji Jokosatriyo, Bronto Sutopo and Aditya Fadlurohman

Resource Geology   76 ( 1 ) e70030   2026.02  [Refereed]

Research paper (journal)   International Co-author

DOI

Trace elements and sulfur isotopes of sulfides at the Leon sediment-hosted gold deposit, Ratatotok district, North Sulawesi, Indonesia: Constraints on the genesis of ore formation

Muhammad Arba Azzaman, Ryohei Takahashi, Pearlyn Manalo, Andrea Agangi, Manuel Nopeia, Hinako Sato, Arifudin Idrus, Doly R. Simbolon, and Renaldi Suhendra

Resource Geology   71 ( 1 ) e70028   2026.02  [Refereed]

Research paper (journal)   International Co-author

DOI

Petrography, geochemistry, and genesis of the Okohongo copper-silver deposit in the Pan-African Kaoko Belt, Opuwo, Kunene, Namibia

Abner Nghoongoloka, Ryohei Takahashi, Pearlyn Manalo, Andrea Agangi, Hinako Sato, Manuel Nopeia, Nigel Blamey, Tavis Enno and Rob Bowell

Journal of African Earth Sciences   237   106069   2026.02  [Refereed]

Research paper (journal)   International Co-author

DOI

Geochemistry and U-Pb zircon geochronology of granite at the Pilok Sn-W deposit, Thailand: Implications for Late Triassic tin metallogenesis

Mallika Intachai, Ryohei Takahashi, Andrea Agangi, Marlina A. Elburg, Punya Charusiri, Pearlyn Manalo, Hinako Sato, Cendi D.P. Dana, and Manuel Nopeia

Resource Geology   76 ( 1 ) e70027   2026.01  [Refereed]

Research paper (journal)   International Co-author

DOI

Replacement of ores recorded by textures and chemical compositions of sphalerite: An example from the Furutobe Kuroko deposit, Akita, Japan

Manuel Nopeia, Ryohei Takahashi, Andrea Agangi, Pearlyn Manalo and Hinako Sato

Geological Journal   Early View   1 - 25   2025.12  [Refereed]

Research paper (journal)   International Co-author

DOI

Apatite and biotite geochemistry constraints on the petrogenesis of the granites in Bangka Island, Indonesia: Implications for tin mineralization

Enrico Gilrandy Wahyu Suharjo, Ryohei Takahashi, Andrea Agangi, Syafrizal, Pearlyn Manalo, and Manuel Nopeia

Resource Geology   75 ( 1 ) e70017   2025.09  [Refereed]

Research paper (journal)   International Co-author

DOI

Geochemistry and U-Pb geochronology of garnet from the Somerset and Arab gold deposits, Vumba Greenstone Belt, northeastern Botswana: implications for the timing of gold mineralization

Lebogang Mokane, Andrea Agangi, Ryohei Takahashi, Thierry Bineli Betsi, Kelebogile Phili, Manuel Nopeia, Tebogo Kelepile, Mayuko Fukuyama, Zibisani Bagai, and Pearlyn Manalo

Resource Geology   75 ( 1 ) e70012   2025.07  [Refereed]

Research paper (journal)   International Co-author

DOI

Kuroko deposits of NE Japan: the product of high-temperature, shallow felsic volcanism in a deepening continental rift

Andrea Agangi, Gabriela Nogo Retnaningtyas Bunga Naen, Manuel Nopeia, Hossain Amini, Ryohei Takahashi and Pearlyn Manalo

Terra Nova   37   377 - 383   2025.05  [Refereed]

Research paper (journal)   International Co-author

DOI

Late Eocene to Pliocene magmatic evolution and its association with gold mineralization in central western Sulawesi, Indonesia

Renaldi Suhendra, Andrea Agangi, Ryohei Takahashi, Marlina A. Elburg, Muhammad Zain Tuakia, Hartaja Wicaksono, Hinako Sato, Iwan Setiawan

Journal of Asian Earth Sciences   281   106506   2025.03  [Refereed]

Research paper (journal)   International Co-author

DOI

The use of combined C-Mg isotope compositions of carbonates from orogenic Sb-Au deposits as a tracer of fluid interaction with sea-floor altered crust

Andrea Agangi, Axel Hofmann, Takuya Echigo, Robert Bolhar, Daisuke Araoka, Vincent Mashoene, Lucia T. Ndhlovu, Ryohei Takahashi, Pearlyn C. Manalo

Chemical Geology   673 ( 5 ) 122442   2025.02  [Refereed]

Research paper (journal)   International Co-author

DOI

Fluid origins and ages of Au mineralization of the Hosen 8-2 vein, Hishikari deposit, Kagoshima, Japan

Jonathan Macuroy, Ryohei Takahashi, Akira Hara, Yoshinori Okaue, Akira Imai, Pearlyn Manalo, Hinako Sato, and Andrea Agangi

Journal of Geochemical Exploration   268   107602   2025.01  [Refereed]

Research paper (journal)   Domestic Co-author

DOI

Mineralization characteristics of the Hokuryu epithermal Au-Ag deposit, Hokkaido, Japan

Omar Baculna Soberano, Ryohei Takahashi, Pearlyn Manalo, Andrea Agangi, Hinako Sato, and Manuel Nopeia

Resource Geology   75 ( 1 ) e70003   2025.01  [Refereed]

Research paper (journal)   International Co-author

DOI

Characteristics of the Kematu epithermal gold deposit at Tboli, Mindanao, Philippines

Alan Royce B. Tizon, Jillian Aira S. Gabo-Ratio, Pearlyn Manalo, Ryohei Takahashi, Ma. Yna Rose D. Garcia, and Juan Alex Vianne D. Amoroso

Resource Geology   74 ( 1 ) e12339   2024.10  [Refereed]

Research paper (journal)   International Co-author

DOI

Genesis of sediment-hosted copper and silver mineralization at the Omatapati prospect, Kaoko Belt, Opuwo district, Kunene region, Namibia

Abner Nghoongoloka, Ryohei Takahashi, Pearlyn Manalo, Andrea Agangi, Hinako Sato, Helke Mocke, Manuel Nopeia, Nigel Blamey, Tavis Enno, and Rob Bowell

Resource Geology   74 ( 1 ) e12341   2024.10  [Refereed]

Research paper (journal)   International Co-author

DOI

Timing and origin of gold mineralization in the Neoproterozoic Xixano Complex, Mozambique Belt, northeastern Mozambique: Case study of the Nanlia and Makorongo prospects

Manuel Nopeia, Akira Imai, Kotaro Yonezu, Ryohei Takahashi, Andrea Agangi, and Daud Jamal

Journal of African Earth Sciences   218   105350   2024.07  [Refereed]

Research paper (journal)   International Co-author

DOI

Geological characteristics and ore-forming conditions of the Tasikmadu porphyry Cu-Au prospect in Trenggalek, East Java, Indonesia

Arifudin Idrus, Genki Kaneko, Ryohei Takahashi, Finlan Adhitya Aldan, Trifatama Rahmalia, and Hinako Sato

Geological Journal   59   2990 - 3016   2024.07  [Refereed]

Research paper (journal)   International Co-author

DOI

Sulfur isotopic variations in the products of the 1895 CE eruption at Zao volcano (NE Japan): Implications for connecting eruption source and syn-eruptive magmatic-hydrothermal processes

Takumi Imura, Tsukasa Ohba, Ryohei Takahashi, Pearlyn Manalo, Hinako Satoh, Masao Ban, Aoi Hirata, and Antonio M. Álvarez-Valero

Journal of Volcanology and Geothermal Research   452   108127   2024.06  [Refereed]

Research paper (journal)   International Co-author

DOI

Mineralogy and geochemistry of the Mupane and Shashe gold deposits of the Tati Greenstone Belt (NE Botswana): Implications for mineral deposit models and exploration

Kelebogile Phili, Thierry Bineli Betsi, Tebogo Kelepile, Ryohei Takahashi, and Lebogang Mokane

Economic Geology   119 ( 3 ) 551 - 571   2024.05  [Refereed]

Research paper (journal)   International Co-author

DOI

Textural-compositional evolution of pyrite and metal remobilization during low-grade metamorphism of metapelite: Contribution to gold mineralization in the Luk Ulo Complex, Central Java, Indonesia

Renaldi Suhendra, Ryohei Takahashi, Andrea Agangi, Akira Imai, Hinako Sato, and Nugroho Imam Setiawan

Ore Geology Reviews   166   105966   2024.02  [Refereed]

Research paper (journal)   International Co-author

DOI

Lateral variations in the Hosen 8-2 vein in the Hishikari deposit, Japan: Implications for high Au-grade zone

Jonathan Macuroy, Ryohei Takahashi, Akira Hara, Yoshinori Okaue, Akira Imai, Pearlyn Manalo, Hinako Sato, and Andrea Agangi

Resource Geology   73 ( 1 ) e12318   2023.08  [Refereed]

Research paper (journal)   Domestic Co-author

DOI