Presentazione sul tema: "EGT-Southern segment. Vertical component record-section. The data are displayed in common shot gather, normalized to maximum amplitude, bandpass filetered."— Transcript della presentazione:
EGT-Southern segment. Vertical component record-section. The data are displayed in common shot gather, normalized to maximum amplitude, bandpass filetered 1-15 Hz and time reduced to 6 km/s. Example of DSS data-1986 S T-X/6 (sec) N Offset (km) M. Maistrello (1), G. Musacchio (1) and C. Marcocci (2) (1)Sezione di Milano, INGV, Italy; (2) Centro Nazionale Terremoti, INGV, Italy The DATABASE Deep seismic Refraction and Wide-Angle-Reflection (R/WAR) data is information of primary interest for the understanding of Lithosphere formation and evolution. In the past two decades seismic velocity models, resulting from several deep controlled source seismic programs, have led to the understanding of the architecture of the lithosphere of relevant tectonic areas. It is getting more and more important archive the seismic data on ready-to-use platforms for further modeling, large syntheses and planning of future new projects. Today, seismic data are commonly digitally recorded and therefore easily archived and stored with a given format. However, paper records or analog magnetic tapes, produced in early days of controlled source seismology programs, are valuable data that might be lost if a proper digitization and archiving process is not applied. ReWARD (Refraction Wide Angle Reflection Database) aims to assemble all the deep seismic R/WAR data collected over Italy and surrounding seas ( km), archive them and make them available to the scientific community. Analog seismic records, mostly single component, collected before 1994 are 10% of the whole dataset and consist of about 200 profiles (partially reversed) for about km of total length data. Some of these profiles were never modeled using the modern 2D ray-tracing techniques. They image the lithosphere at great depths, although with a low spatial resolution (about waveforms). The remaining 90% of the data cover only km length with about waveforms. They are 3- component, high-resolution R/WAR digital waveforms generated by air-gun shooting and acquired on- shore Italy. For each study area, digital (or digitized) waveforms will be stored with a common format. Additional information built-in the archive will be topographic and geologic maps, published seismic cross-sections and references. The archive will be published on our web-page from which the user may retrieve on-line the built-in information and download the data upon request. ARCHIVING SEISMIC R/WAR DATA from ITALY and SURROUNDING SEAS REFERENCES de Franco R., Musacchio G., Polarization Filter with Singular Value Decomposition. Geophysics, Ferrari R., Maistrello M., L'esplorazione sismica profonda in Italia: dati Deep Seismic Soundings in rete!. In: Bollettino CILEA n. 63 (1998) Ferrari R., Maistrello M., "Deep Seismic Soundings: il progetto continua. In: Bollettino CILEA, n. 74 (2000). Gaudiosi G., Guerra I., Luzio D., Milano G., Musacchio G., Struttura crostale del Tirreno Sud-orientale. XIX CNR-GNGTS Meeting, Rome, Nov Gasparini P. and Tomoves Group, Looking inside Mt. Vesuvius. In: EOS, n. 79, Gruppo Sea-Land Crop-Mare II, Wide angle reflection Sea-land CROP-Mare II & LISA Project – Section Atlas. De Franco R., Caielli G., Corsi A. Editors, Milan, CNR-IRRS, Maistrello M., Menu_hp: una procedura unificata per la digitalizzazione, elaborazione, archiviazione, trasmissione di segnali sismici analogici, in ambiente Basic-Hp. Technical report CNR-IRRS 1996; 68 pp. Morelli C., Metodi per una maggiore conoscenza della Crosta terrestre. In: CNR: Ricerca & futuro, 19, Maistrello M., Corsi A., DOL-2000: larchivio Web delle registrazioni sismiche a rifrazione profonda. Technical Report INGV, Milan, 2001; 17 pp. Nicolich R., Il profilo Latina-Pescara e le registrazioni mediante OBS nel Mar Tirreno. I° CNR-GNGTS Meeting, Rome, Nov Slejko D., Metodi e prospettive per una maggiore conoscenza della crosta terrestre (Dossier). In: Bollettino CNR Ricerca & Futuro, n.19 (2001). SM6-P0089 Acknowledgements Here listed are all the institutions who participated to data collection. They kindly provided the data for this database. We apologize for possible oversights. CROP-MII land recording. 3 component NMO corrected record-sections. The data are displayed in common receiver gather, normalized to maximum amplitude and bandpass filetered 2-15 Hz. a, b, c are raw data; d, e, f are polarization filtered data [de Franco and Musacchio, 2002]. (VNMO= 6.2 and 3.5 km/s for P- and S-waves, respectively) Example of high-resolution 3-components data-1994 SENWSENWSENW Large on/off-shore shots Land seismic lines Airgun lines and land recordings OBS and small off-shore shots Thyrreanian Sea Vertical component record-section. The data are displayed in common shot gather, normalized to maximum amplitude, bandpass filtered 1-20 Hz and time reduced to 8 km/s [ Nicolich, 1981]. Example of obs data-1979 WE T-X/8 (sec) Offset (km) Relation Entity (a standard flow-chart in DB programming) a self-consistent Entity possible relations between Entities Entity legend EXPERIMENT survey description PROFILE seismic lines BANG shooting parameters BANG_PLACE shot-point information STATION recording site information SENSOR sensor(s) properties ACQUISITOR data-logger(s) properties BIBLIO references IMAGE bitmaps library of the project WAVEFORM header information ( at the moment real data are stored on disk) Relations between entities: (used for the 'Profile to Bang' relation, using 'Rel_put' table)(in the DB, the 'Foreign-Key' method was used) 'one to many' 'many to many'