The DataMonitor Tool
- Plots the real time data string from our digitizers / recorders
- Displays timing information and sampling rate.
- Auto-scale, manual scale, zoom in/out, variable window length
The DataMonitor Tool
The DataViewer user interface supports powerful features which are divided into five groups, each selected by clicking on the appropriate menu. Clicking the appropriate icon on the tool bar can also access most of the available features.
The DataViewer screen works with and displays data from one or two files at a time. When first opened the graphic display is blank. You must select and load a file before the other functions of the DataViewer screen become available.
The DataConverter makes it possible to quickly and easily convert CORE24/32 files to ASCII or MiniSEED format. You can use DataConverter to convert a single file, a group of files or all files in a directory.
The Helicorder window shows seismogram recordings of a particular seismographic station during the 24-hours period. The graph is read like a book, from left to right and top to bottom (this is the direction that time increases). As with a book, the right end of any horizontal line “connects” with the left end of the line below it. The colors of the horizontal lines have no particular significance. Different colors have been used to facilitate the reading of the graph. The horizontal and the vertical lines are presented to indicate equal intervals of time. The tool plots CoRe24/32 data files.
The Helicorder application supports dynamic data visualization. When a source directory is selected, a new file search procedure starts. If there are valid files in the source directory, the graph is updated and a new file search procedure is executed every a period of time defined by the duration of the files. Otherwise, the search procedure is executed every 1 minute by default. When a day changes and a new directory is created, the source directory also changes. The new graph will be updated as soon as the first file of the new day is created. Until then the graph of the previous day is used.
Each time the graph is updated a new bitmap file is created. In addition, the user has the option to send this file to a server using FTP functions.
The SeedLink protocol is a robust data transmission intended for use on the Internet or private circuits that support TCP/IP. The protocol is robust in that clients may disconnect and reconnect without losing data, in other words transmissions may be resumed as long as the data still exist in the servers buffer. Requested data streams may be limited to specific networks, stations, locations and/or channels. All data packets are 512-byte Mini-SEEDrecords. Enhancements to the SeedLink protocol supported by the DMC’s server allow network and station codes to be wildcarded in addition to the location and channel codes. GEObit instruments support SeedLink protocol therefore data are transferred in real-time.
SeedLink is a real-time data acquisition protocol and a client-server software that implements this protocol. The SeedLink protocol is based on TCP. All connections are initiated by the client. During handshaking phase the client can subscribe to specific stations and streams using simple commands in ASCII coding. When handshaking is completed, a stream of SeedLink “packets” consisting of a 8-byte SeedLink header (containing the sequence number) followed by a 512-byte Mini-SEED record, is sent to the client. The packets of each individual station are always transferred in timely (FIFO) order.
Data processing software for CORE24/32 data files
The Event Detection software has been developed on the following independent modules:
During the develop of the software, many seismic algorithms were tested for the detection of the arrival times of the events. When data are noisy, best results were obtained by applying the “recursive STA/LTA” which combines speed and reliability as it is a real-time sequential algorithm and its implementation is easy. However, the algorithm has one basic disadvantage when it has to be applied in random noise signals. The trigger threshold value is fixed so the algorithm will not be applicable in noisy data. This disadvantage has been eliminated with the use of variable threshold level (GEObit patent), which automatically is set from each file being processed. Thereby the sequential behavior of the algorithm recursive STA / LTA algorithm is maintained and it still remains real time.
The raw data have to be organized in files named with the station number. Station numbers must start from 01 to 99. This dataset can be under any directory like “visits_9_10_11_12” or whatever. The output directory has to be initially created from the user, and it’s path has to be added to the appropriate field on the software form. The parameters of the ini.txt file have to be set by the user, and it’s path has to be added on the software form as well. Then just pressing the “Search” button, the software will do the seismic event detection, and select and copy all the files.
Further data post processing will be applied by the user, using the “CleanUp” procedure. Plotting of the data will be done, in group of stations, like they have been processed. All the trigger points of the waveform will be grayed from the data plotter helping the user to confirm if the detected signal is a seismic event or a false event.
Advanced Seismic Software Applications. Automated event detection & picking software. The software can be used for very small seismic events extraction from raw data, acquired for Passive / Active Seismic Tomography applications, hydraulic fracturing applications.
SeismPlus is a software package for interactive visualization and analysis of earthquake seismograms. SeismPlus performs waveform display of one or more sets of single trace seismograms, automatic and manual arrival time picking, hypocenter location of local, regional and teleseismic events, magnitude determination as well as import/export of several waveform and phase data formats.
SeismPluts acceps data at the next formats: CoRe24/32, Mini-SEED, or ASCII . The SeismPlus accepta also HYPO71 files. Processed waveforms are output in CoRe24, Mini-SEED or ASCII data format, while phases and locations are saved only in the HYPO71 format. Other formats are available upon request.
SeismPlus runs on any PC with Microsoft Windows 10/8/7/Vista/XP/2000 operating system.