Earth hummock. Earth hummocks are among the periglacial phenomena. The knoll covered with vegetation is |about 0.5 m high.| J-STAGE
The braided course of the Jokulfell downstream from Hofsjokull.| J-STAGE
Palagonite ridge formed by subglacial eruption. Langjokull glacier in the background.| J-STAGE
Dettifoss waterfall. The waterfall is 44 m high. The river water is rich in suspended sediments and the waterfall volume is the greatest in Iceland.| J-STAGE
Valley of Eldgja. The 934-40 Eldgja eruption occurred along a 75 km-long fissure.| J-STAGE
Normal fault at Thingvellir. The boundary between the North American plate on the left-hand side and the Eurasian to the right.| J-STAGE
Geyser Strokkur. The geyser erupts at 5-10 minute intervals.| J-STAGE
Jokulsarlon lagoon. The Breidamerkurjokull glacier has been retreating since about 1920. The lagoon formed at the glacial front shows a yearly increase.| J-STAGE
Reykjavik is a smokeless city. Almost 100% of the electricity and the heating depends upon hydropower and geothermal energy.| J-STAGE
Gullfoss waterfall. The two-step cataract has a total drop of 32 m.| J-STAGE
Lakagigar fissure eruption. The 1783-84 Laka- gigar eruption resulted in a great famine, due to which Iceland lost 20% of its population.| J-STAGE
Basaltic lava field, the Svartshengi geothermal power plant (right), and the Blue Lagoon (left).| J-STAGE

Latest Issue

Journal of Geography (Chigaku Zasshi), 2013 Vol.122 No.2

2013 Vol.122 No.2

Conduit Drilling at Unzen Volcano

Drilling into the magmatic path was carried out at Unzen Volcano during the period 2002-2004 to understand the eruption mechanisms of the volcanic eruption during the period 1990-1995. This project was sponsored partially by the International Continental Scientific Drilling Program (ICDP).
(Upper left) Rig site of Unzen Scientific Drilling Project (USDP-4 site), about 1 km north of the summit at an altitude of 840 m. The mountain with bared rocks in the background is the lava dome (altitude of about 1400 m) formed at the summit during the 1990-1995 eruption. Directional drilling was carried out toward the area below the summit from this site. The photograph was taken in June 2004.
(Lower left) USDP-4 rig site on the northern middle slope of Mount Unzen. The height of the rig is about 55 m. Taken from the dome in November 2003.
(Upper right) Drilled core taken from conduit zone, which is a composite dyke. This is pyroclastic dyke (tuffisite) in volcanic breccia, which formed during magma ascent. Drilled depth is 1748 m (about 100 m below sea level). The diameter is about 13 cm.
(Middle right) Conduit dacite lava from the 1990-1995 eruption, taken from a drilled depth of 1977 m (about 150 m below sea level). The rock has already been altered hydrothermally. The diameter is about 4 cm.
(Lower right) Photomicrograph of the conduit dacite lava with corroded quartz phenocryst. The diameter is about 2.5 mm.

(Photograph and explanation: Setsuya NAKADA)

Special Issue on “Current Status of On-land Scientific Drilling in Japan and Its Prospects”

An Overview: Special Issue on “Current Status of On-land Scientific Drilling in Japan and Its Prospects”

Yasufumi IRYU, Tetsuro HIRONO, Osam SANO and Hitoshi KOIDE

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 227.

DOI:10.5026/jgeography.122.227

Preface for the Special Issue on “Current Status of On-land Scientific Drilling in Japan and Its Prospects”

Yasufumi IRYU, Tetsuro HIRONO, Osam SANO and Hitoshi KOIDE

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 230.

DOI:10.5026/jgeography.122.230

Japanese Continental Scientific Drilling Project Promoted before ICDP (Review Article)

Nobuaki NIITSUMA

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 233.

DOI:10.5026/jgeography.122.233

International Continental Scientific Drilling Program (ICDP) and Land-based Drillings in Japan (Review Article)

Tetsuro URABE

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 250.

DOI:10.5026/jgeography.122.250

Scientific Results of Volcano Drilling and Future Prospects (Original Article)

Setsuya NAKADA

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 258.

DOI:10.5026/jgeography.122.258

Scientific Drillings of Lacustrine Sediments in Japan: A Review (Review Article)

Fujio KUMON

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 273.

DOI:10.5026/jgeography.122.273

Strata Formation in a Tectonically Subsiding Coastal Lowland: Example from Alluvium in the Echigo Plain, Central Japan (Original Article)

Susumu TANABE

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 291.

DOI:10.5026/jgeography.122.291

Researches on Tsunami Deposits Using Sediment Cores: 3.4 ka Tsunami Deposit in the Rokken-gawa Lowland near Lake Hamana, Pacific Coast of Central Japan (Original Article)

Osamu FUJIWARA, Yoshiki SATO, Eisuke ONO and Masatomo UMITSU

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 308.

DOI:10.5026/jgeography.122.308

Fault-Drilling Investigation of Earthquake Slip Behavior and Physicochemical Processes (Review Article)

Tetsuro HIRONO, Kentaro OMURA, Koichiro FUJIMOTO, Hisao ITO, James J. MORI and Hiroshi SATO

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 323.

DOI:10.5026/jgeography.122.323

Understanding Geothermal Systems in Ductile Zones and Their Perspective for Power Generation with Engineered Geothermal System Technologies (Original Article)

Hirofumi MURAOKA, Hiroshi ASANUMA and Hisao ITO

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 343.

DOI:10.5026/jgeography.122.343

Terrestrial Deep Subsurface Biosphere Studies and Their Social Relevance (Review Article)

Takeshi NAGANUMA

Journal of Geography (Chigaku Zasshi), 2013, 122(2), 363.

DOI:10.5026/jgeography.122.363

Pictorials

Pictorial 1: 1934 and 1936 Kita-daito-jima Drilling: The First and Only Deep Drilling into Coral Reefs in the Northern Philippine Sea

Yasufumi IRYU

Journal of Geography (Chigaku Zasshi), 2013, 122(2), iii.

DOI:10.5026/jgeography.122.iii

Page 70 of 71

Copyright © 2015 TOKYO GEOGRAPHICAL SOCIETY (estabished in 1879). All rights reserved.