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About flyovers

Dr. Masaya Hirashima and Prof. Daichi Nozaki, in a press conference on June 29th last year at the University of Tokyo, suggested that forgetting (i.e., memory decay), which is usually considered as an inconvenient and inefficient factor in human behavior, plays an important role in minimizing the brain effort for controlling human behaviors, reminding us of the “Lethe”, one of the five rivers underground in Greek mythology, where all those who drank from it experienced complete forgetfulness. Sometimes, it may be necessary for us to actively drink the water of the “Lethe” to forget memories, particularly those of traumatic or disturbing events or experiences such as those in earthquakes. However, we, earthquake engineering and disaster mitigation experts are surely responsible for transferring as much lessons as possible based upon precise and tragic reality of disasters.

During my 27-years career at the IIS, University of Tokyo, I have been involved in total 153 recon trips for 43 overseas and domestic earthquakes. Reaching the age for planning retirement, I tried to compile the data from all involved recon trips. However the fact that unexpectedly many photos were not within my recollection has given me a full recognition that it would take much longer time for me to do it. Thinking back what I have done in the latter half of my career at the University of Tokyo, considerable efforts were devoted to collect and analyze geomorphological changes in terrains, given problems that strong ground motions were often unavailable in seriously devastated areas thus frustrating all attempts to rationally deduce the whole picture of the devastation at a great cost of many lives and properties.

This CD contains the following customized tours on the Google Earth:
(1) Flyover tour along the Tokyo Bay Shore Area liquefied in the March 11th 2011 Off the Pacific Coast of Tohoku earthquake [1]-[4], and
(2) Flyover tour across the mountains of Mid-Niigata Prefecture jolted by the 2004 Mid-Niigata Prefecture Earthquake [5]-[8].
Flyover tour (1) provides a bird-eye view of the liquefaction-induced soil subsidence of the Tokyo Bay Shore Areas detected from raster images converted from airborne LiDAR (Light Detection and Ranging) data before and after the earthquake. To eliminate deep-seated tectonic displacements and systematic errors of LiDAR surveys, the template matching technique was used for clusters of pile-supported buildings and bridge piers chosen as templates in source images of the target areas. In the flyover tour (2), DEMs before and after the earthquake are compared to highlight thousands of landslides as well as tectonic displacements over the entire stretch of the affected mountain terrain. At every location in the guided tours, you can view any terrains and contents and look around as you wish.

The tours put in the CD are yet only a very small fraction of the data, and a lot of unfinished fragments of data remain on my bookshelves. However I will keep doing my best so that they will appear piece by piece on the following URL:

Taking this great opportunity, I would like to express my sincere thanks to all of you who have supported me for so long.

Kazuo KONAGAI

Acknowledgement

Maps, photos and data provided herewith are the fruit of the following investigations and research projects:

  1. JSCE, JAEE and MEXT Recon trips,
  2. Earthquake damage in active-folding areas: Creation of a comprehensive data archive and suggestions for its application to remedial measures for civil-infrastructure systems, Research and Development program for Resolving Critical Issues, Special Coordination Funds for Promoting Science and Technology, Ministry of Education, Culture, Sports, Science and Technology, 2005-2007
  3. Scientific surveys for long-lasting geotechnical problems caused by large earthquakes and their implementations for rational rehabilitation strategies,” Konagai K. Leader of the project, 2008 Grant-in-aid for scientific research (A) no. 20254003, Ministry of Education, Culture, Sports, Science and Technology (MEXT). 2008-2010
  4. Detection of Lagrangian displacements along activated seismic faults and their implementations for rational rehabilitation strategies, Konagai K. Leader of the project, 2008 Grant-in-aid for scientific research (A) no. 23246087, Ministry of Education, Culture, Sports, Science and Technology (MEXT). 2011-2013
  5. Investigations for long-lasting geomorphological changes triggered by the Great East Japan Earthquake of 2011, Grant-in-Aid for Social Action Programs for 2011-2013, The Foundation for the Promotion of Industrial Science.
The author is indebted to both the Foundation for the Promotion of Industrial Science and the Japan Society for the Promotion of Science who have provided the author's team with financial supports for conducting the airborne LiDAR surveys. The author's deepest appreciation also goes to all members of the project-steering committee organized under the Japan Society for Civil Engineers as the core of the project. It sould not be forgotten that Mr. Tadayoshi Nagashima and Mr. Zahid Ameen, former mayors of Yamakoshi and Muzaffarabad, respectively, municipalities affected by the 2004 Mid-Niigata Prefecture Earthquake and the 2005 Kashmir earthquake, have devoted themselves for rehabilitations of their home lands though they were also erthquake victims, and they have provided the author's teams with all necessary helps.

References

About liquefied ground subsidence
  1. Konagai K., Kiyota T., Suyama S., Asakura T., Shibuya K. and Eto C., 2013. “Maps of soil subsidence for Tokyo Bay shore areas liquefied in the March 11th Off the Pacific Coast of Tohoku Earthquake”, Soil Dynamics and Earthquake Engineering, 53, 240-253.
  2. Konagai K., Kiyota T., Asakura T., Suyama S., Shibuya K. and Eto C., 2011. Subsidence map of the Tokyo Bay Area liquefied in the March 11th Great East Japan Earthquake, 15th World Conference on Earthquake Engineering, Sept. 24-28, Lisbon, Portugal.
  3. Konagai K., Asakura T., Suyama S., Kiyota T., Shibuya K. and Eto C., 2011. Soil subsidence map of the Tokyo Bay Area liquefied in the March 11th Great East Japan Earthquake, Proceedings of the International Symposium on Engineering Lessons Learned from the 2011 Great East Japan Earthquake, March 1-4, 2012, Tokyo, Japan, 855-864.
  4. Asakura T., Suyama S., Konagai K., Eto C., and Shibuya K., 2012. Verification of accuracy of liquefied soil subsidence map of Urayasu from air-borne LiDAR survey and displacement inflicted damage to structures and their subsoils, Journal of JSCE, Division A: Structural Engineering/ Earthquake Engineering & Applied Mechanics, 66(1), 1278-1284, in Japanses.
About the 2004 Mid-Niigata Prefecture Earthquake
  1. Earthquake damage in active-folding areas: Creation of a comprehensive data archive and suggestions for its application to remedial measures for civil-infrastructure systems, Research and Development program for Resolving Critical Issues, Special Coordination Funds for Promoting Science and Technology, Ministry of Education, Culture, Sports, Science and Technology,
    http://active-folding.iis.u-tokyo.ac.jp/archive/en/
  2. Konagai, K. Earthquake-induced soil displacements and their impact on rehabilitations, Proc., Japan Academy, 87(8) (Ser.B), 433-449, 2011.
  3. Konagai, K, Takatsu, S. Kanai, T., Fujita, T., Ikeda, T. and Johansson, J.: Kizawa tunnel cracked on 23 October 2004 Mid-Niigata earthquake: An example of earthquake-induced damage to tunnels in active-folding zones, Soil Dynamics and Earthquake Engineering, 29(2), 394-403, 2009.
  4. Konagai, K, Fujita, T., Ikeda, T. and Takatsu, S.: Tectonic deformation buildup in folded mountain terrains in the October 23, 2004, Mid-Niigata earthquake, Soil Dynamics and Earthquake Engineering, 29(2), 261-267, 2009.