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February 17th, 2020
Local Organizing Committee of ESG6ESG6 Call for Blind Prediction Participation
The first International Symposium on the Effects of Surface Geology on SeismicMotion (ESG1) was held during 1992 in Odawara, Japan. The inaugural ESG1
symposium conducted blind prediction experiments designed to understand the observed
amplification of seismic motions in Ashigara Valley (Kanagawa Prefecture, Japan) and in
Turkey Flat (California, U.S.A.). The following ESG2 symposium, held during 1998 in
Yokohama, Japan, focused on simultaneous simulation of the near-source strong motion
observed during the 1995 Kobe Earthquake. ESG3 was held during 2006 in Grenoble,France, where blind tests were also conducted; the subsurface structure was empiricallyestimated using array microtremors and ground motions were numerically simulated forsites in Japan and France. ESG4, held during 2011 in Santa Barbara, USA, and ESG5,during 2017 in Taipei, Taiwan, mainly focused on VS30 issues and site effects(respectively) related to the shallow structure. No experiments were conducted for theESG4 and ESG5 symposiums.
In the tradition of ESG experiments, the next ESG6 conducts blind predictions
to identify the subsurface structure, followed by simulations of ground motions whileconsidering the estimated subsurface structure, for an undisclosed site in the Kumamoto
Prefecture, Japan. Consistent with the ESG international scheme, The ESG6 international
symposium will take place in Kyoto during 15–17 March 2021. The ESG6 BlindPrediction is neither a drill nor for training purposes. Moreover, ESG6 neither plans toexercise the state-of-knowledge for estimating subsurface structures nor to predict groundmotions in an idealized environment where all necessary information are readily available.
Rather, ESG6 intends to improve our understanding about the state-of-art and its effects
on an environment where information are sparse or lacking, as occurs in practice.
Individual and/or team participants who are interested in the exercise are welcomed tocontribute to any part of the Blind Prediction.
The Blind Prediction will focus on identifying the subsurface structure and/or simulating
the weak ground motion, as well as the mainshock of the 2016 Kumamoto Earthquake, ata strong motion observation site in Kumamoto Prefecture, Japan, where undisclosed
strong motion data have yet to be released (unpublished).

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The Blind Prediction will consist of three steps. Participants will be asked to submit theirresults, step-by-step (see below), and submitting results for only one (or, less than fullparticipation) part(s) of the Blind Prediction is also encouraged. Participants may stop or
start at any part of the exercise.
Step 1. Identification of the subsurface structure at the site
Several observations will be recorded to collect data for use with non-invasive analysis
techniques to investigate the subsurface velocity structure. All information about the arraymicrotremor and MASW data, as well as metadata, will be distributed to the participants.
The participants can choose from any technique(s) that he/she decides is the best use of
the distributed data to identify the subsurface velocity structure.
These aforementioned elements relate to the COSMOS (Consortium of Organizations forStrong Motion Observation Systems, www.strongmotion.org) International Guidelines
for Applying Noninvasive Surface-based Methods When Characterizing Seismic Site
Conditions project—these observations were conducted to partially fulfill the COSMOS
Guidelines development for identifying subsurface structure.
Step 2. Simulation of weak motions observed at the site
The target weak motion observation to be selected will be limited to linear soil response.
The participant is encouraged to simulate the weak motions based on the participant’s
resultant velocity model in Step 1; however, if the participant lacks or disregards resultsfrom Step 1, a generic one-dimensional velocity structure model will be distributed bythe Committee. Weak motion data of earthquakes (excluding the target weak motion) will
be distributed. Source parameters of earthquakes for weak motions will also be distributedin case the participants need the information.
Step 3. Simulation of strong motion observed at the site during the mainshock of the2016 Kumamoto Earthquake
The strong motion observations recorded at the surface will include non-linear soil
response. Information about the ground motions observed during the mainshock of the2016 Kumamoto Earthquake at a relatively stiff site about few kilometers north-west of
the target site will be distributed. Additional information about the shallow velocity
structure at the site will also be distributed. The information about the source rupture
process model(s) of the mainshock of the 2016 Kumamoto earthquake that are open to
the public will be included in the distributed information.

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Expected information and data to be distributed:
1. Array microtremor data and MASW data recorded at the site for Step 1.
2. Several weak motion data of earthquakes, excluding the target weak motion, observedat the site for Step 2.
3. Ground motion data of foreshock and aftershock of the 2016 Kumamoto earthquake,excluding the target motion, observed at the site for Step 3.
4. Source parameters of earthquakes for the weak motions.
5. Ground motion records of the mainshock of the 2016 Kumamoto earthquake at a
relatively stiff site near the target site.
6. Generic one-dimensional velocity structure for Steps 2 and 3.
7. Information about the source rupture process model(s) of the mainshock of the 2016
Kumamoto earthquake.
Results to be submitted:
1. One-dimensional velocity structure model inverted from the array microtremor data for
Step 1.
2. Time series of the predicted broadband weak motion acceleration and velocity for Step2.
3. Time series of the predicted broadband strong motion acceleration and velocity for Step3.
4. Non-linear response information used for/derived from the analysis for Step 3.
5. Explanation of the methodology and the results. In addition, point(s) of discussion thatthe participants want to address in the Blind Prediction session.
Format for submission of the results will be specified when the information and datafor will be distributed.

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Schedule:January 29th,2019 Call for blind prediction participation
Announcement of the first circular of ESG6thApril 19 ,2019 Call for blind prediction participation (2nd version)
May 23rd,
2019 Call for blind prediction participation (3rd version)
June 28th,
2019 Deadline for statement of interest to participate in the blindprediction (for Steps 1, 2 and 3)
stJuly 1 ,2019 Distribution of data for Step 1
Announcement of the second circular of ESG6st
September 1 , 2019 Call for abstracts for regular sessions of ESG6
October 1st,
2019 Exhibition registration openth
December 6 , 2019 Deadline for submitting results of Step 1 and abstracts
January 6th, 2020 Deadline for submitting results of Step 1 and abstracts
December 6th 2019 Deadline for abstracts for regular sessions of ESG6January 6th2020 Deadline for abstracts for regular sessions of ESG6th
December 20 , 2019 Distribution of additional information for Steps 2 and 3
January 20th, 2020 Distribution of additional information for Step 2
February 14th, 2020 Distribution of additional information for Step 2
March 1st,
2020 Distribution of generic one-dimensional velocity structure modelstApril 1 ,2020 Distribution of generic one-dimensional velocity structure model
Distribution of additional information for Step 3stMay 1 ,2020 Registration open
July 30th,
2020 Deadline for extended abstracts for results of Step 1
Deadline for extended abstracts for regular sessions of ESG6
August 31st, 2020 Deadline for submitting results of Steps 2 and 3 and abstracts
September 30th 2020 Early bird registration deadline
December 18th, 2020 Deadline for extended abstracts for results of Steps 2 and 3
January 31st, 2021 Online registration deadline
March 15th-17th,2021 ESG6
The schedule written in italic are for the ESG6 and related events.
Those who plan to participate in the blind prediction, please contact the organizing
committee by the following contact address.
Contact: esg6-bp@jaee.gr.jp, Web site: http://www.esg6.jp/

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