Fumihiko Ikegami
Earth Science Watcher in Japan. Master of Geology and None. I am myself, not employers.
- Very interesting paper from China. They drilled two 10-km holes in 2025 and found hydrocarbon from that depth. Zhu & Huang (2026) Comm. Earth Environ. Ultradeep drilling beyond 10 km revealing new insights into Earth systems and resources www.nature.com/articles/s43...
- Diagram: Structure of the Deep Earth - by Fumihiko Ikegami ikegami.substack.com/p/diagram-st... The figure I've posted before + A bit of additional notes.
- geoign/Geoscience_Figures: My original scientific figures for Geosciences github.com/geoign/Geosc... Adobe Illustrator .ai file is also available for editing. CC BY-NC 4.0 License.
- Some impressive eruption photos (between 2004-2025) from Kirishima Geopark www.facebook.com/media/set?va...
- English version! The colors of the mantle are based on the actual mineral colors (except lithospheric mantle). If you have any idea or suggestion, let me know!
- Holiday drawing. (Don't worry. I'll create the English version too.)
- JMA has raised the alert level for Yakedake volcano in Japan due to the increased seismicity as well as the tilt change suggesting an edifice inflation. (Google Translated Image attached) www.jma.go.jp/bosai/volcan...
- The list of the past eruptions of Yakedake in the recent 10000 years, by Geological Survey of Japan. (Google Translated image attached) gbank.gsj.jp/volcano/cgi-... Very active in the past, but not in the recent time.
- Where Volcanoes Form on Earth? open.substack.com/pub/ikegami/... Many textbooks are still stuck at the level of understanding from the formative era of plate tectonics—over 50 years ago. In this article, I organize where on Earth volcanoes occur.
- Links to Geology-related Open GIS Data open.substack.com/pub/ikegami/...
- I wrote this article in Japanese back in the New Year and now it is also available in English at my substack. I hope some people find it useful.
- What happens in my mind when I "read" the topographical contours. 1→2. Compute the Slope (Focus onto the dense-sparse of the contour lines). 2→3. Integrate the Structure (Track the ridges and valleys). 3→4. Synthesize the Terrain. (Overlaying data to build the 3D mental model.)
- A magnificent ocean sediment transport from Yangtze River to Okinawa Trough is seen today. It is probably due to the strong westerly seasonal wind these days. weather-models.info/latest/himaw...
- Million years of geology in Ryukyu Islands, explained in single image.
- Seismotectonics of Hokkaido, the collisional area between NE Japan and Kuril arcs. GEBCO, AW3D30, GSHHG, GlobalCMT (M>4, 1991-2020), Uchide (2022)(GSJ, AIST), JMA Unified Hypocenters (1998-2021, D<20 km), Seamless Geological Map (GSJ, AIST), Volcanoes and Calderas (GSJ, AIST)
- Dear US citizens, we can't wait another 3 years for you to fix your government.
- The download page of USGS's slab2 dataset looks gone. www.usgs.gov/data/slab2-a... Here is the alternative download link. I downloaded it in May. drive.google.com/file/d/1lrP1...
- And in case if you prefer easy vector contours in one file, use this geopackage file I made. drive.google.com/file/d/1wSZd...
- JAMSTEC R/V Kaimei is livestreaming from Mariana's NW Rota-1 volcano right now... www.youtube.com/live/hIb3QTz...
- Geological Survey of Japan has released the raw drone videos of the eruption of Shinmoedake back in July. storage.repository.aist.go.jp/1104/index.h... DJI_20250703140503 has the footage of the most intense part of the eruption.
- Igneous mafic-silicic something. Don't ask me what was happened here in 120 Ma tonalite. Shikanoshima, Fukuoka, Japan.
- Same igneous bodies but in a different form. Not far from the previous outcrop.
- I am pretty impressed to Gemini 3. It is the first AI I am scared of. We dont probably need human researchers to find a scientific question anymore. Only lab rats and field explorers will survive this major extinction. Good luck.
- The underwater seismometer network is so great, as evidenced from yesterday's EQ off-Tohoku. Reposting unofficial visualization by x.com/kotoho76/sta...
- I really really wish everyone in the subduction zone around the world has this. It is the best thing that Japan has developed in the past decades.
- Japan Coast Guard found no significant bathymetric change after the earthquake swarm in Tokara Islands. The mystery deepens... www.kaiho.mlit.go.jp/info/kouhou/...
- Updates from JMA regarding the eruption of Iwojima (Ogasawara Io-to). www.data.jma.go.jp/vois/data/re...
- JMA reported Iwojima (Ogasawara Io-to) is erupting. Image from Himawari-9 satellite. weather-models.info/latest/himaw...
- Today is the National Disaster Prevention Day in Japan, commemorating the 1923 Great Kanto Earthquake which devastated Tokyo and Yokohama. Here is the ground displacements map after the EQ, which was of course made without GPS or InSAR... www.gsi.go.jp/kohokocho/ko...
- The map was made by the 4 years levelling campaign with >4000 people・days... Crazy stuff.
- Hey Nano-Banana, please super-resolution and enhance this low-resolution satellite image. Make it like the imagery from the state-of-the-art 10-cm resolution satellite. Strictly keep the composition and viewing angle of the original image. Add immence details to the original blurry image. 😱😱
- Please, don't do that...
- Automatic Colorization has reached this level now (Qwen Image Edit i2i model). Sakurajima 1914, Bezymiannny, 1956, Quizapu 1932. It is increasingly important to keep the original data.
- The strong eruption of #Shinmoedake this morning, from JMA and municipal government cameras. Reddish growing has been observed for the first time this year.
- How much of the ocean has been mapped? 2025 Edition. (GEBCO 2025 SID + SRTM15Plus v2.7 TID)
- I have just learned that there is a temple in Myammer with a floating pumice displayed as the holy object... www.sukima.com/38_myanmar20... I need to visit there some day after the peace is back.
- Osarizawa Mine was one of the largest copper mine in Japan. It has been accepting visitors after its closure in 1950's, but no more from 2026. The memories of Japan as World's top mining country is fading away.
- After a bit of search about insects repellant for a fieldwork, I found it safe to say Icaridin (EU) / Picaridin (US) is much better than the old DEET. journals.sagepub.com/doi/full/10....
- Was in the field yesterday. Found two cute mountaineers.
- JMA mascots: Harerun and Volken
