Although the proposal is presented by individuals,it should be emphasized
that this will be a team effort involving all the scientific and technical
staff of thethree organizations: the NRA Seismology Division, Jordan,the GII
Seismology Division, Israel, the Center of Earth Sciences and Seismic Engineering
of An Najah National University, Palestinian National Authority. Their activities
will be assisted and complemented by individuals from the US Geological Survey,
the Building Research Center of the Jordanian Royal Scientific Society and the
Faculty for Civil Engineering, The Technion, Israel. The tasks to be performed are
listed below and shown on the chart in Fig.2.
-
Initiation
There is no doubt that is great expertise among the scientists of the US
Geological Survey regarding current earthquake hazard assessment practice and
new methods are now being studied. It is important that during the initial
stages of our project we shall be exposed to these state of the art methods
and procedures.Dr. W. Hays of the USGS will be our link to that knowledge
and expertise. During the earliest stage of ourproject we plan to organize a
workshop at which state ofthe art hazard assessment procedures will be
presentedand discussed in the lightof their applicability to theregion.
We shall also usethis gathering as a training course for those of us who
are less familiar with seismological aspects associated with the SvE and/or
engineering requirements.
-
Collating Existing Geological, Geophysical and Seismological Data
Mr.Abdel Qader, Head of the NRA Seismology Division will coordinate
the activities of the team responsible for compiling existing geological,
geophysical and seismological data. Based on these data, the main task of
this team will be to propose the segmentation of the DST and its branching
faults and division of the regioninto seismogentic zones. It is likely that
this team willbe assisted by experts of other directorates of the NRA and
experts from the Israel Geological Survey. This teamwill require several
joint meetings at which to exchangedata and ideas.
-
Creating a Unified Earthquake Catalogue
We are extremely concerned by the inconsistencies and significant
differences between the earthquake catalogues of Jordan and Israel (which
should be practically the same). It will again be the task of Mr.Abdel Qader
to lead and coordinate activities to yield a unified earthquake catalogue
for the DST. The activities will involve (but not be limited to):
The identification of events that have significantly different locations
Verification/authentication of the location of
disputed historical earthquakes
Re-determination of hypocenters (where necessary)
of instrumentally recorded earthquakes
Defining and determining a unified magnitude scale
for all earthquakes in the catalogue
The product of this task will be an epicenter map.
In order to complete this task, Dr. W. Hays, also as coordinator of the
RELEMR program, will help in acquiring contributions from neighboring
countries to assure the completeness and reliability of the catalogue.
In that respect,and with the help of the USGS, we hope that this task will
involve scientists from other Arab countries who are currently hesitating
to join this project.
-
Assessment of Seismicity
A team led by Dr. A. Shapira, Director of the GII Seismology
Divion, will use the products of tasks (1) and (2) to provide a
quantitative assessment of the completeness of the earthquake catalogue
and an assessment of the long term seismicity level in each of the defined
seismogenic zones. We also hope that scientists of other Arab countries
will join us (directly or indirectly) in that effort.
-
Enhancement of Monitoring Capabilities
Most of the activities associated with enhancing seismic
monitoring capabilities will be performed in Jordan and the territory of
the Palestinian National Authority. These activities will involve:
Upgrading the quality of the radio telemetry of the JSO network by
replacing VHF telemetry with UHF telemetryof about 20 stations. This should
be a first steptowardsdigital telemetry to be installed in a laterstage.
Acquisition of a calibration kit for fieldoperation and joint
calibration of all stations in the network.
Installation of 10 new digital strong motion accelerometers in main
cities in Jordan and the West Bank.
Upgrading the recording center of NRA by installing a new Seismic
Data Acquisition System.
Organizing a training course during which the GII software for data
acquisition and routine seismicanalysis will be installed, presented and
excised. GII will prepare the necessary modifications
Based on these and already existing seismic systems, the national
organizations will collect earthquake data: Location, Magnitude (on a unified
scale),SeismicMoment, stress Drop (Brune’s model) and fmax Estimations.
-
Application of the SvE Method
Dr. A. Shapira will lead the team investigating the applicability of the
new approach suggested by Beresnev and Atkinson (1998) to synthesize free surface
ground accelerations (hard rock conditions). This teamwill also be responsible
for evaluating relationships between static and dynamic earthquake source
parameters,evaluation of the attenuation of the zero-frequency displacement
spectra with distance and Q-values (see e.g., Shapira and Hofstetter, 1993).
This analysis will be based on the data acquired from existing Short Period (SP)
and Broad Band (BB) stations and from the new (upgraded) SP stations. In this
analysis we shall also incorporate updated information (if will be available) of
source functions and mechanism of strongearthquakes. Data from strong motion
instruments willbe used to test and calibrate parameters in the procedures for
computing synthetic accelerograms.
-
Analysis of Strong Motion Accelerations
Few strong earthquakes that occurred in the last decade have triggered
several existing strong motion instruments in Israel and in Jordan. These
data are essential for calibrating the analytical models in the SvE as well as
examining the reliabilityof the simulations. It will be the task of
Prof. Dabbeek, Director of the Center for Earth Sciences andSeismic Engineering
of An-Najah National University, to lead a team who will be responsible for the
analysis of the strong motion data. The analysis will include measurements of
peak ground motions, determination of response spectra after deconvolution, if
necessary, of local site effects.
-
Characterizing Dynamic Parameters of Buildingss
As explained in the above, the seismological input required for the
building code depends also on building characteristics. Prof. J. Dabbeek,
in close cooperation with researchers of the Building Research Centers in
Jordan and Israel, will lead a team responsible for the following activities:
Typifying buildings common in the region.
Instrument and perform measurementson selected buildings in order
to determinethe empiricaldynamic characteristics of the buildings.
Develop analytical models that can predict the dynamic
characteristics of local buildings
Define the spectral band pass and the damping ratios for which
the acceleration response functions will be computed, and consequently
the earthquake hazard maps will be prepared.
-
Preparation and Publication of Official Seismic Hazard Maps
We plan to produce the following maps:
Horizontal Peak Ground Acceleration for hard-rock conditions and prescribed
probability of occurrence.
Expected ground accelerations for different areas within the region, at
different frequency ranges anddamping ratios and for a prescribed probability of
occurrence in hard-rock conditions.
These products will be the final output of the teams’activities throughout the
project.Technically, it will involve computer runs of the modified SvE over a dense
grid oflocations across the study region. A special workshop will beheld to discuss
the best way of presenting the results in map form. National committees for building
codes will be approached for advice and presentation of their preferences.
|