Workshop on
"Probing Earth Media Having Small-Scale
Heterogeneities"
Date: November, 22 (Mon), 2004
Place: Aoba Memorial Hall, Tohoku University,
Sendai, Japan
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=== Workshop Program is uploaded. ===
=== Workshop Proceedings is uploaded (Proceedings.zip: 28MB) ===
Haruo Sato (Geophysics, Science, Tohoku Univ.,
sato@zisin.geophys.tohoku.ac.jp)
Osamu Nishizawa (AIST, Tohoku Univ., osamu-nishizawa@aist.go.jp)
Hiroshi Asanuma (Environmental Studies, Tohoku
Univ., asanuma@ni2.kankyo.tohoku.ac.jp)
The 21st Century COE Program "Advanced
Science and Technology Center for the
Dynamic Earth", Tohoku University
The Society of Exploration Geophysicists
of Japan (SEGJ)
The Seismological Society of Japan (SSJ)
The precise knowledge of Earth medium heterogeneity is useful for the quantitative prediction of earthquake shocks, the exploration and exploitation of underground resources, and the preservation of the Earth's environments. It also serves as a resource for the study of tectonics and the evolution process of the Earth. Among the probing technologies of the Earth's heterogeneity, seismic methods have been extensively developed: reflection and refraction surveys on the basis of layered structure models and seismic tomography based on travel-time readings in various scales. In recent years, however, the resolution limit of probing technologies has become an important issue of earthquake seismology and exploration geophysics. Small-scale heterogeneities, such as cracks, joints, cavities, and geothermal fluid, modulate seismic waves and also generate coda waves. Large-scale heterogeneities are often referred to as the deterministic structures, whereas small-scale heterogeneities are often considered to be random fluctuations from deterministic structures. Current studies have revealed the importance of seismic wave scattering due to small-scale heterogeneities. Seismic coda waves have been intensively studied for the past three decades and have revealed important concepts and images about the real existence of small-scale heterogeneities in the Earth. Stimulated by coda studies, stochastic approaches have been developed for interpreting seismogram envelopes in relation to the spectral structures of random inhomogeneities associated with tectonic conditions, where phase information is discarded because of the incoherence of scattered waves. Numerical techniques have been extensively developed for the simulation of waves through highly heterogeneous media. Physical modeling by using ultra-sonic waves clarified the collapsing of seismic wave fronts in rock samples. Recent development in the reconstruction of the Green function from coda waves is based on the positive use of phase information embedded in multiple scattering waves due to distributed random heterogeneities.
The purpose of this workshop is to present and discuss recent advancements in the field of seismic wave propagation in Earth media containing small-scale heterogeneities, such as characterization of medium heterogeneities, technologies for probing medium heterogeneities using seismic waves, laboratory experiments of wave propagation through heterogeneous media, modeling and analysis of wave propagation through random media, and so on. We cordially invite you to attend this workshop to make a link between seismology and exploration geophysics and to share collaborative research.
Researchers and graduate students from exploration geophysics, seismology, geology, rock mechanics, geo-engineering, and other related fields are especially welcome.
Nov. 22, 8am to 6 pm. A banquet will be given on Nov. 22th evening.
There will be a few sessions in the Workshop.
1. Exploration geophysics: geothermal field and others
2. Wave scattering in heterogeneous media: modeling and experiments
3. Coda waves (proposed by Aki)
Recently, the cause of intraplate earthquakes has been attributed to the weakness of the ductile part of lithosphere underlying the seismic brittle part in a global scale (Zoback and Zoback, 2002), in a regional scale (Iio et al., 2002), and in the scale of several hundred meters (Aki, in press; Jin et al., in press). The smallest-scale evidence relies on the temporal variation of coda Q such as observed by Jin and Aki (1989, 1993) attributed to the fracture density in the ductile part and leads to a promising way for a deterministic earthquake prediction. This idea is supported by numerous studies that revealed a strong positive correlation between the geographic variation of coda Q-inverse with that of seismic activity throughout the world. The variation is most spectacular from Japan to Tibet through Korea and North China (the coda Q is low in Japan, high in Korea, low in North China, high in the Ordus region and low in Tibet with an order of magnitude change). This suggests a promising use of the coda Q mapping for the seismic hazard estimation of the world's most disastrous earthquake belt connecting Japan and Spain, and hopefully for an intermediate-term earthquake prediction. We invite papers related to this topic.
>>Reference Papers (click here)
Workshop Program (PDF)
Aki Keiiti (NIED, Japan; IPGP, France):
A New Look at The Spatial Correlation Between Coda Q and Seismicity
>>Abstract (text)
/ (PDF)
Recently Aki (2004) and Jin et al. (2004) interpreted the temporal correlation between coda Q and seismicity discovered earlier by Jin and Aki (1989, 1993) in terms of a hypothesis of earthquake loading process called g brittle-ductile interaction hypothesish. The present paper is a natural extension of the idea to the well-known spatial correlation between coda Q and seismicity.
In this hypothesis, intraplate earthquakes are attributed to stress concentration by the plate-driving forces on the brittle part of the lithosphere due to the underlying weak and easy-to-deform ductile part as supported by Zoback and Zoback (2002) in a global scale, and by Iio et al. (2002) in a regional scale. The coda Q-inverse is a measure of the density of fractures in the ductile part in this hypothesis, expressing the weakness of the ductile part and hence the stress concentration on the overlying brittle part.
In this paper I shall review the result of Jin and Aki (1988) on the coda Q mapping in China and some recent results from Spain, India, Korea and other areas in the zone of the most disastrous earthquakes connecting Japan with Spain, and propose a systematic mapping of coda Q in the zone. The migration of low Q region concurrent with that of seismicity in North China and other areas suggested by these works encourages us to pursue the coda Q mapping for the purpose of long-term earthquake prediction.
Michel Campillo, E. Larose, L. Margerin, A. Paul
(LGIT and LPMMC, Université Joseph Fourier and CNRS) :
Equipartition, correlation and time symmetry.
>>Abstract (PDF)
Tae Woong Chung[1], Yun Kyong Park[2],
Ik Bom Kang[2]
([1] Sejong Univ., Korea,
[2] Institute of Geoscience and Mineral Resources, S. Korea) :
Crustal QLg-1 in South Korea
Using the Source Pair/Receiver Pair Method
>>Abstract (PDF)
Michael Fehler[1], K. Sabra[2],
P. Gerstoft[2], P. Roux[2], and
W. Kuperman[2]
([1] Los Alamos National Laboratory, USA,
[2] Scripps Institution of Oceanography) :
Extracting Seismic Profiles from Background Seismic Signals
>>Abstract (PDF)
Furumoto Muneyoshi and Hiramatsu Yoshihiro
(Kanazawa Univ., Japan) :
Characteristic frequency of a temporally varying coda wave as a proxy
for the dimension of small scale heterogeneity in the crust
>>Abstract (PDF)
Ito Shin1, Kaieda Hideshi2, Aoyagi Yasuhira2 and Hayashi Kazuo3
([1] Akita Pref. Univ.,JAPAN, [2] CRIEPI, Japan, [3] Tohoku Univ. Japan) :
Fracture Characterization by Using Resonance of Penny-Shaped
Fluid-Filled Crack Model in Cooper Basin, Australia
>>Abstract (PDF)
Izumi Tanetomo[1], Asanuma Hiroshi[1],
Kumano Yusuke[1], Soma Nobukazu[2],
Niitsuma Hiroaki[1], Roy Baria[3] and
Sophie Michelet[3]
([1] Tohoku Univ., Japan, [2] AIST, Japan,
[3] GEIE, France)
:
Data Acquisition and Analysis of Microseismicity from the Stimulation
at Soultz 2003 by Tohoku University and AIST, Japan.
>>Abstract (PDF)
Jin Anshu
(ADEP & NIED, Japan) :
Coda Q in Japan
>>Abstract (PDF)
D. Kiyashchenko, N. Smirnova and V. Troyan
(Saint-Petersburg state Univ., Russia) :
Simulation of scattering of waves in elastic body with cracks during the
destruction process: the possibility of application of fractal analysis of
seismic waveforms for earthquake hazard monitoring.
>>Abstract (PDF)
Kumano Yusuke[1], Moriya Hirokazu[1],
Asanuma Hiroshi[1], Izumi Tanetomo[1]
Soma Nobukazu[2], Kaieda Hideshi[3],
Tezuka Kazuhiko[4], Doone Wyborn[5] and
Niitsuma Hiroaki[1]
([1] Tohoku Univ., Japan, [2] AIST, Japan,
[3] CRIEPI, Japan, [4] JAPEX Research Center, Japan,
[5] Geodynamics Ltd., Australia)
:
Analysis of similar microseismicities induced during hydraulic
stimulation of HDR geothermal reservoir at Cooper Basin, Australia
>>Abstract (PDF)
Won Sang LEE[1], Kiehwa LEE[2],
Haruo SATO[1]
([1] Tohoku Univ., Japan, [2] Seoul National Univ., Korea)
:
Regional difference of the lower mantle heterogeneity
revealed from envelope analysis
>>Abstract (PDF)
Maeda Takuto, Sato Haruo, and Nishimura Takeshi
(Tohoku Univ., Japan) :
Modeling of Conversion Scattering between Rayleigh and
Body Waves in a Randomly Inhomogeneous Half-Space
based on the Born Approximation
>>Abstract (PDF)
Jorge L. Martins
(Observatório Nacional, Ministry of Sci. & Technology, Brazil) :
The Effects of Crack Density on Elastic Impedance Logs
>>Abstract (PDF)
Kawahara Jun1 and Yomogida Kiyoshi2
([1] Ibaraki Univ., Japan, [2] Hokkaido Univ., Japan) :
SH wave envelopes in 2-D media with discrete scatterers:
Theories vs. wave simulations
>>Abstract (PDF)
Matsumoto Satoshi
(Kyushu Univ., Japan) :
Estimating scatterer density in the crust by dense seismic
array processing
>>Abstract (PDF)
Matsuoka Tatsuro and Shiraishi Hidetaka
(Saitama Univ., Japan) :
S-wave velocity structures precisely estimated from the microtremor survey method in the central Kanto Plain, Japan
>>Abstract (PDF)
Moriya Hirokazu[1], Niitsuma Hiroaki[1]
and Roy BARIA[2]
([1] Tohoku Univ., Japan, [2] EEIG Heat Mining, France) :
Multiplet-clustering analysis for revealing structural details
within the seismic cloud
>>Abstract (PDF)
Muto Jun, Kawada Yusuke and Nagahama Hiroyuki
(Tohoku Univ., Japan) :
Micromorphic Continuum with Defects and Lattice Preferred Orientation:
Application to Seismic Anisotropy in Polycrystals
>>Abstract (PDF)
Nakahara Hisashi (Tohoku Univ., Japan):
Correlation distance of seismograms for closely located events:
Implication for the heterogeneous structure around the source region
of the 1995 Kobe earthquake, Japan
>>Abstract (PDF)
Nemoto Katsumi, Moriya Hirokazu and Niitsuma Hiroaki
(Tohoku Univ., Japan) :
Effects of increasing rate in pore fluid pressure on hydraulically
induced slip and implication for aseismic slip
during hydraulic stimulation
>>Abstract (PDF)
Nishimura Takeshi1, Tanaka Satoru1, Yamawaki Teruo1, Yamamoto Hidekazu2, Sano Takashi2,
Sato Minemori1, Nakahara Hisashi1, Uchida Naoki1, Hori Shuichiro1, and Sato Haruo1 ([1] Tohoku Univ., Japan, [2] Iwate Univ., Japan):
Temporal changes in seismic velocity of the crust around Iwate volcano,
Japan: analyses of repeated active seismic experiment data from 1998 to
2003
>>Abstract (PDF)
Nishizawa Osamu (National Institute of Advanced Industrial Science and Technology, Japan):
Effect of Small-Scale Random Heterogeneity on Phase
Fluctuation of Seismic Waves
>>Abstract (PDF)
Ru-Shan WU and Yingcai ZHENG (University of California, Santa Cruz,
USA) :
Revisit the Theory of Transmission Fluctuation in Random Media
>>Abstract (PDF)
Sato Haruo (Tohoku Univ., Japan)
and Michael Korn (Leipzig Univ., Germany):
Synthesis of Elastic-Wave Envelopes based on the Markov Approximation
in 2-D Random Media Characterized by a Gaussian ACF
>>Abstract (PDF)
Saito Tatsuhiko (AIST GREEN, JSPS Research fellow) :
Synthesis of scalar-wave envelopes in anisotropic random media
using the Markov approximation
>>Abstract (PDF)
John A. Scales, Alison Malcolm and Amy Hinkle
(Colorado School of Mines, USA):
Meso-scale ultrasonics in open and closed disordered systems
>>Abstract (text)
/ (PDF)
When it comes to the sensitive dependence on initial conditions, rays
behave in a fundamentally different way than waves. Or we could say
equivalently that classical particles behave in a fundamentally
different way than quantum ones. Classical particles (or rays) are
characterized by individual trajectories in phase space. In contrast
waves, or quantum particles, are characterized by all possible paths
connecting the endpoints of an experiment; this is most easily
visualized as a Feynman path summation. When a wave hits a small
scatterer, the wavefront quickly heals and downstream of the scatterer
it my be hard to tell that anything has happened. Whereas if two
slightly perturbed rays hit a scatterer, they may end up in completely
different regions of phase space. This latter behavior conforms to
our usual notion of chaos, whereas the stability of wave propagation
has led some to entirely deny the possibility of wave chaos. In this
talk I will describe our experiments in ultrasonic wave propagation in
strongly scattering media. By using lasers to excite and detect waves
we can perform the measurements without touching the samples, thereby
faithfully recording the wavefield everywhere on the surface of the
samples. We will see that at late times in multiple scattering wave
experiments useful notions of chaos can be defined, and that in this
chaotic regime, deterministic information about the underlying average
system can be extracted. This opens up the possibility of
using chaotic wave speckle to perform deterministic imaging. In
spite of the increased theoretical complexity of multiple-scattering,
there may be important advantages to use of this speckle.
Spetzler Jesper (Delft Univ., Netherlands):
Validation and Implementation of First-Order Finite-Frequency
Effects
in Seismic Imaging Experiments
>>Abstract (text)
/ (PDF)
The behavior of finite-frequency waves propagating in heterogeneous media
with structures smaller in size than the Fresnel volume is fundamentally
different from what is predicted by ray theory. The high-frequency
approximation in ray theory does not allow to account for
wavefield scattering effects. I present a linear finite-frequency
theory for the traveltime and amplitude of propagating transmitted
and reflected wave. Single-scattering effects are included in the
finite-frequency approach. For finite-frequency waves, the
traveltime and amplitude are sensitive to structures inside the
Fresnel volume surrounding the geometrical ray path, joining
the source and receiver. The traveltime is most sensitive to anomalies
next to the ray while the amplitude has the maximum sensitivity
on the ray path. The linear finite-frequency wave theory is
combined with the Maslov theory for caustic formation,
to leading order, to account for non-linear ray bending effects
inherent to triplications in the wavefront. The first-order
scattering theory is validated in a real 3D and numerical 2D
ultrasonic experiment. In these ultrasonic tests, small-sized
spherical balls with positive as well as negative velocity perturbations
are centered between the source point and receiver array in order to
synthesize
the fundamental characteristics of the finite-frequency wave theory.
The first-order scattering approach has been implemented
in seismic experiments such as crosswell tomography, reflection
seismic imaging and in global surface wave tomography.
Takaghi Nobumasa, Sato Haruo and Nishimura Takeshi
(Tohoku Univ., Japan):
Flow of Scattered Waves' Energy From the Fore-Arc to the Back-Arc
in Eastern Japan Revealed From the Cross-Correlation Analysis of
Coda Waves
>>Abstract (PDF)
Takahashi Tsutomu1, Sato Haruo1,
Nishimura Takeshi1 and Obara Kazushige2
([1] Tohoku Univ., Japan, [2] NIED, Japan):
Envelope Broadening of High-frequency P- and S-waves
in Northeastern Honshu, Japan: Regional Difference in Relation
to the Quaternary Volcano Distribution
>>Abstract (PDF)
Watanabe Toshiki (Nagoya Univ., Japan):
Waveform tomography of time-lapse seismic data
for velocity and attenuation
>>Abstract (PDF)
Yamawaki Teruo, Nishumura Takeshi and Hamaguchi Hiroyuki
(Tohoku Univ., Japan) :
Temporal change of seismic structure around Iwate volcano
investigated from waveform cross-correlation of similar
earthquakes
>>Abstract (PDF)
Yajima Takahiro and Nagahama Hiroyuki
(Tohoku Univ., Japan) :
Seismic ray path in anisotropic medium based on higher-order geometry
>>Abstract (PDF)
Yoshimoto Kazuo
(Yokohama City Univ., Japan) :
Spatial distribution of the S-coda-wave energy in Japan
>>Abstract (PDF)
Information for Oral Presenters
- Meeting room is equipped with the following equipment:
1-LCD projector
1-Overhead projector
1-Screen
1-Pen style laser pointer
- If you want to use another LCD or Overhead projector,
please contact LOC:
scatws04@zisin.geophys.tohoku.ac.jp.
- Time for each presentation is 25 minutes including 5 minutes
for discussion. Please keep staying within the allotted time.
- If you have questions, please contact LOC:
scatws04@zisin.geophys.tohoku.ac.jp
Information for Poster Presenters
- Each presenter is provided with a poster board
with 1120mm high and 1690mm wide. Each poster board will be marked
with an individual poster number. The poster number can be found in
the program of the workshop on the meeting web site.
- All the poster boards will be put in the back of the meeting room.
- Poster session is scheduled from 12:30 to 14:30 on Nov. 22.
Presenters should be available for at least 1 hour during
the poster session.
- Please set up your poster before the poster session, if possible
before 9:00AM. The meeting room will be open from 8:30AM.
- Push pins are available at the registration desk.
- If you have questions, please contact LOC:
scatws04@zisin.geophys.tohoku.ac.jp
Instructions for Submission of Abstracts
- Submission of the abstract (Deadline: September 30)
- Receipt mail is sent back from LOC within a few days.
- Submission of the registration form (Deadline: September 30).
There is a deadline to submit your abstract to the Workshop. All authors are required to submit their abstract to the Local Organizing Committee before September 30, 2004. Notice of the acceptance of the abstract will be e-mailed by the Local Organizing Committee. A preliminary program is also released on the WEB site in early October.
To submit your abstract, (Deadline: September 30, 2004)
Abstracts should be submitted to the Local Organizing Committee by e-mail (scatws04@zisin.geophys.tohoku.ac.jp) before September 30, 2004. The abstracts received after the deadline, September 30, 2004, may not appear in the workshop. All manuscripts should be in English. Authors are required to include their e-mail addresses in the abstract, and to submit their abstracts in PDF format (Other formats can not be accepted.). Abstracts should be 2 or 4 pages in one-column format on international A4 sheets. The top margin of 30mm, the left, the right, and the bottom margins of 25mm are requested. Text is to be typed single spaced in at least 9 point Times New Roman. The first page of the abstract, centered on the top below the top margin, should include the abstract title, the authors' names, and their affiliations. Corresponding author please provide e-mail addresses. Figures and illustrations are included in the page count. All of the contents of a manuscript including figures will be printed in monochrome even if a manuscript in a color format is provided. Please see an example in PDF format.
Submission of the abstract must be followed by the author's registration. You can download the registration form from the following link: 2004scatWS04-register.rtf. The abstracts without the registration form will not be included in the Workshop Proceedings.
When submitting the registration form, please indicate your NAME, and AFFILIATION(S), and PATICIPATION in the workshop and a reception. If you submit your abstract, please also indicate TITLE, AUTHOR(S), INSTITUTION(S), and a preferred way of presentation (oral or poster) for the presentation. We will make every effort to accommodate your choice of presentation form, but the Program Committee reserves the right to re-assign abstracts to balance the program. If you do not indicate a favorite presentation form, this is decided by the Program Committee.
For people from foreign countries: Please contact with our secretary, Ms. Kumi Hanzawa (hanzawa@zisin.geophys.tohoku.ac.jp).
This workshop will be held in advance of "The 7th SEGJ International Symposium: Imaging Technology" on November 24-26, 2004 in Sendai sponsored by the Society of Exploration Geophysicists of Japan (SEGJ). Each attendant to this workshop is encouraged to present a paper at this international symposium, too. Detailed information of this international symposium is available on http://www.segj.org/is7/index.html#contents.
* Workshop on "Stochastic Seismic Waves and Underground Heterogeneity", Convened by Nishizawa, Geological Survey of Japan, Tsukuba, Japan, Dec. 14, 1998 (
http://www.aist.go.jp/GSJ/~g0192/workshop/home.htm).
* Workshop on "Seismic Waves in the Heterogeneous Earth: More Applications to Seismology and Exploration Geophysics", Convened by Sato and Niitsuma, Tohoku University, Sendai, Japan, July, 10, 2003 (
http://www.scat.geophys.tohoku.ac.jp/pdf/WS_Sendai2003/Workshop0710programE.pdf).
Sato's Lab: http://www.zisin.geophys.tohoku.ac.jp/index.html
Nishizawa's Lab.: http://staff.aist.go.jp/osamu-nishizawa/index_E.html
Asanuma's Lab.: http://www.earth.tohoku.ac.jp/niitsumalab/index_ni-e.html
IASPEI Task Group: http://www.scat.geophys.tohoku.ac.jp/index.html
The 21st Century Center of Excellence Program
"Advanced Science and Technology Center
for Research of Dynamic Earth": http://www.geophys.tohoku.ac.jp/21coe/COE-e.htm
Sendai city with a population of one million is the political, economical, academic, and cultural center of the Tohoku (northeastern) region of Honshu, Japan. It is located about 300 km north of Tokyo. The city has a rich cultural heritage stretching back 400 years to its founding by feudal lord Date Masamune. A mild climate, 400- year tradition, a harmonious combination of beautiful nature and urban facilities, and a bountiful harvest from the land and the Pacific Ocean - all these blessings make Sendai attractive. The main streets are sheltered by lush zelkova and the Hirose River's clean water runs through the center of the city. Sendai's nickname 'Mori no Miyako' (literally city of green) illustrates this perfectly. It is also well- known as an academic city: universities and research institutes within the city have made many innovative technological developments. The main campus of Tohoku University is located on the Aobayama Hill west of the downtown. You can find useful information about Sendai from the following web sites.
*Access to Sendai:
http://www.kankou-miyagi.net/english/
*Accommodations:
http://www.stcb.or.jp/v_tour_html_e/sendaicb/hotel.htm
*Sightseeing:
http://www.siip.city.sendai.jp/kankokoryu/english/index.html
http://www.pref.miyagi.jp/kankou/English_version/main.htm
http://travel.japan-tohoku.com/enarea.htm
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View from the top of the Aobayama-Hill |
The main campus of Tohoku University is located on the Aobayama Hill west of the downtown.
You can find useful information about the university and Sendai from the university web site:
http://web.bureau.tohoku.ac.jp/international/home-e.html.
Aoba Memorial Hall (BLDG #31) in the Aobayama-Campus
Bus starts from the Bus Terminal #9 at the Sendai Railway Station.
| Route |
Kougakubu Keiyu
Via Faculty of Engineering |
For Miyakyou-dai, Aoba-dai |
Stop at Kougakubu Chu'ou |
| Route |
Rigakubu Kougakubu Keiyu
Via Faculty of Science, and Engineering |
For Aobajyoushi-Jyunkan |
Stop at Kougakubu Chu'ou |
Location of Sendai http://www.siip.city.sendai.jp/kankokoryu/english/index.html
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