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Earthquake Parameters

Parameter

Description

Validation

Data Type

ECODE

(primary key)

primary key of the earthquake record archived in the earthquake-database and associated with the records of the databank

cannot be missing

I6

ENAME

name by which the earthquake is commonly known (e.g. Spitak, aftershock of Kocaeli earthquake)

cannot be missing

A50

EFE

name of the Flinn Engdahl region where the epicentre is located (Flinn, Engdahl & Hill, 1974)

cannot be missing

A60

ECTRY

name of the country where the earthquake is located

cannot be missing

A30

earthquake date and time

dd.MM.yyyy

dd

EDAY

day of the year in which the earthquake occurred, in UTC

1 dd 31

cannot be missing

I2

 

MM

EMONTH

month of the year in which the earthquake occurred, in UTC

1 MM 12

cannot be missing

I2

 

yyyy

EYEAR

year in which the earthquake occurred, in UTC

yyyy 1933

cannot be missing

I4

hh:mm:ss

hh

EHOUR

hour of the day, on the 24-hour clock, of the earthquake origin time, in UTC

0 hh < 24

cannot be missing

I2

 

mm

EMIN

minutes of the hour of the earthquake origin time, in UTC

0 mm < 60

cannot be missing

I2

 

ss

ESEC

seconds of the hour of the earthquake origin time, in UTC

0 ss < 60

cannot be missing

I2

Epicentre co-ordinates

lat ns lon ew

lat

ELAT

northing of the epicentre, expressed in degrees, in WGS84

0.0 lat 90.0

cannot be missing

F6.3

 

ns

ENS

latitude hemisphere

N or S

cannot be missing

A1

 

lon

ELON

easting of the epicentre, expressed in degrees, in WGS84

0.0 lon 180.0

cannot be missing

F7.3

 

ew

EEW

longitude hemisphere

E or W

cannot be missing

A1

EDEP

focal depth of the earthquake in km

missing value is -99

I3

Magnitudes

EMB

body-wave magnitude

missing value is -9.9

F4.1

 

EML

local (Richter) magnitude

missing value is -9.9

F4.1

 

EMS

surface-wave magnitude

missing value is -9.99

F5.2

 

EMW

moment magnitude

missing value is -9.9

F4.1

 

EMO

seismic moment, in Nm

missing value is -9.9

E8.2

Epicentral intensity

Io Idef

Io

EINT

epicentral intensity

I Io XII

missing value is blank

A5

 

Idef

EIDF

acronym of the intensity scale on which the epicentral intensity has been determined

missing value is blank,

cannot be missing, if Io is given

A7

EFPS

fault mechanism of the earthquake

cannot be missing

A20

EREF

references to published documents that describe the earthquake-parameters

cannot be missing

A250

Notes on parameters of earthquake-database:
Earthquake Name
If no earthquake name is given by the source, expressed in the reference field, the nearest city/village or region name has been chosen as earthquake name. All known aftershocks are indicated with the prefix "aftershock of ...".
Country
Each country was selected using its recent political boundaries.
Source Date and Time
The origin date and time of the earthquake that generated the strong-motion record is the first means of identification of each event. The source of the origin date and time is always the same as that for the epicentral location and is given in the reference field.
Epicentre Co-ordinates
Epicenters have been culled from special studies, adopted from bulletins of the International Seismological Centre, ISC, National Earthquake Information Center, NEIC, for recent strong earthquakes, and for small events re-assessed from a combination of strong-motion and seismographic data. Its locations were generally re-evaluated on distances based on the time lag between S-wave arrival time and trigger time or S-P lag.
Many of the earthquakes are of moderate magnitude and are reported from a relatively large enough number of stations to ensure reasonable azimuthal coverage. The locations of the earthquakes archived in the database are therefore not likely to be in serious formal error. The latitude and longitude refer to WGS84 (World Geodetic System 1984).
Focal Depth
With the exception of cases for which P and SH wave modeling solutions are available, focal depth comes from the same source as the epicentre.
Magnitudes
Due to the availability of teleseismic data it was not possible to determine the values on all four magnitude-scales for all selected events. However, for each event at least one magnitude value is given.
Whenever possible Ms rather than ML should be used in ground motion studies because the former is the best estimator of the size of a crustal earthquake, and because seismicity in Europe is generally evaluated in terms of Ms so far. Moreover there are no ML determinations in some parts of the study area. The use of a unified magnitude scale in ground motion studies is another important consideration (Ambraseys & Smit, 1998).
Body-Wave Magnitude, Mb
Body-wave magnitude is invariably taken from ISC determinations.
Local (Richter) Magnitude, ML
Local magnitude is the mean value of ML reported in regional and local bulletins.
Surface-Wave Magnitude, Ms
Surface wave magnitudes have been re-calculated for most of the events from the modified Prague formula using maximum amplitude/period ratios of surface waves (Ambraseys & Free, 1997), with station and distance corrections (Ambraseys & Douglas, 2000).
Moment-Magnitude, Mw
Moment magnitude Mw has been converted directly from Mo.
Seismic Moment, Mo
Seismic moments Mo are chiefly CMT Harvard estimates or values obtained from P and SH wave modeling (Centroid Moment Tensor).
Epicentral Intensity, Io
The two character fields give the epicentral intensity and its scale (European Macroseismic Scale 1992 or 1998, EMS92, EMS98; Geofina; Mercalli, Cancani, Sieberg, MCS; Modified Mercalli, MM; Medvedev, Sponheuer & Karnik 1964, MSK64; Rossi Forel, RF) has been defined, despite of a number of problems associated with the assessment of epicentral intensity. The intensity-values have been directly adopted from the literature or from bulletins without re-assessment.
Fault Mechanism
Fault mechanism has been determined wherever possible, from field observations, from source mechanism studies or has been adopted from the literature. Faulting is classified as "normal", "thrust", "strike slip" and "oblique".
References
Only the most important reference to documents or bulletins has been given from where most of the earthquake-parameters were adopted.

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