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QuakeManager allows the user to read the LIS format (COSTA Rica) in a very smooth and efficient way. This format falls in the multichannel file formats where the time series data of each channel are represented as a column. The data represents acceleration data. All channels share the same header data (metadata) and share the same number of acceleration points. There are 34 header lines, and the last header line represents the channels titles.
Below is a snapshot of a sample LIS file format and the description of each header line comes later. Note that any change in any of the header lines will result in unsuccessful import of the record to QuakeManager.
The below descriptions are based on documentation of the original LIS format available at: http://www.lis.ucr.ac.cr/Descargas
1.Agency: Corresponds to the institution that processed the information.
2.Processed on: The date the file was created or reprocessed.
3.Epicenter (Epicenter): The name of the place where the epicenter was located.
4.Station Name: the name of the station
5.Record name: Name of the record.
6.Event Date: the date when the earthquake happened.
7.Event Latitude: Earthquake’s location latitude.
8.Event Longitude: Earthquake’s location longitude.
9.Event Depth: Earthquake depth
10.Event Magnitude: Earthquake magnitude
11.Source type: Type of source according to local (LOCAL) or subduction (SUBDUC). This classification is based on the depth of the event or as reported by the RSN or the OVSICORI.
12.Station code: Given by three letters.
13.Instrument type: Depending on whether it is analog or digital.
14.Serial number: Serial number of the instrument.
15.Station latitude: Station’s location latitude
16.Station longitude: Station’s location longitude
17.Station Elevation: Station’s location elevation.
18.Soil type: Given by a code (S0, S1, S2, S3). See table below.
19.Site condition (Shelter): It refers to the type of shelter in which the instrument is located: most are in one-story structures and that is what we call free field (“FFD”). There are stations located inside buildings either at the top (“BDU”) or at the bottom (“BDG”).
20.Epicentral distance.
21.Hypocentral distance.
22.Azimuth from epicenter to station.
23.Delta t (Sampling): It is record DT. Most instruments are 200 samples per second, while QDRs are 100 samples per second.
24.PGA (Peak Acceleration): PGA of first channel
25.PGA (Peak Acceleration): PGA of second channel
26. PGA (Peak Acceleration): PGA of third channel
27.MIN. Filt. FREQ.: minimum filter frequency
28.MAX. Filt. FREQ.: maximum filter frequency
29.Number of points: Number of acceleration points
30.Soil type definition
31.Station Building conditions
32.Data unit
33.Channels titles
Data is presented in columnar form and in Welsh for each component as indicated. They are given in exponential format with three significant figures.
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Table: Classification of surface geology according to the Applied Technology Council of 1985
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Kind
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Name
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Description
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S1
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Rock
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Effusive volcanic rocks (basalts and andesites), intrusive (granodiorites, monzonites, gabros and syenites), metamorphic (cornubianites), little fissured, with a shear wave speed of 2500 to 4000 m / s.
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S2
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Firm
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Sedimentary rocks (arenites, shales, limestones, breccias and conglomerates), volcanic rocks (pyroclastic flows, lavas and lahars), with clay thicknesses less than 20 m, and wave speeds of 1500 to 1700 m / s.
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S3
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Soft
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Volcanic rocks (lavas and pyroclastic deposits = strongly altered, where the phreatic levels are high, the clay thicknesses of up to 10m above the soil type S2 and shear wave speed of 800 to 1200 m / s.
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S4
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Very Soft
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Volcanic rocks (lahars, ash and tuffs), sedimentary rocks (diatomite, lacustrine and shales), recent deposits (alluvium and colluvium), of low mechanical quality, with shallow water tables, are strongly altered rocks, clay thicknesses greater than 50m on soil types S1, S2 and S3, and with a shear wave speed of 235 to 300 m / s.
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