Table of Contents for this Document File: Name of File Contributing Source File directory/location Information on the region covered Variable Table Format File Sample Data Variable File Additional Documentation ==================================================================== ==================================================================== ==================================== Variable Table The variable table contains a list of parameters contained in the data as well as information on the existence of histograms which can be viewed in GeoVu. File npac.tab for this catalog follows ==================================== DATA SET TITLE: npac PRINCIPAL INVESTIGATOR: CONTRIBUTING ORGANIZATION: NGDC DATA FILE: npac.bin NUMBER OF RECORDS: 1960 ASCII FILE SIZE: 160720 BINARY FILE SIZE: 152880 SUMMARY: This is the composite catalog for the North and Central Pacific Ocean from the NGDC data base. The time covered is: 1868 to 1995 The region covered is: 0 N to 49 N 160 E to 130 W This is a composite catalog from many sources and contains multiple listings for the same event. VARIABLE NAME HISTOGRAM NAME 2. ASCII FORMAT BINARY FORMAT NO. & MIN/MAX VALUES Stat End Type Prc Stat End Type Prc Min. Max. #nonzero source SOURCE.CST 1 3 char 0 1 3 char 0 BCI WEL 1960 century_and_year CENTURY_.LST 4 8 short 0 57 58 short 0 1868 1995 1960 month MONTH.LST 9 10 short 0 59 60 short 0 1 12 1960 day DAY.LST 11 12 short 0 61 62 short 0 1 31 1960 hour HOUR.LST 13 14 short 0 63 64 short 0 1 23 1886 minute MINUTE.LST 15 16 short 0 65 66 short 0 1 59 1919 second SECOND.LST 17 19 short 1 67 68 short 1 1 59 1815 latitude_abs NO HISTOGRAM 20 24 long 3 NOT IN BINARY latitude_ns NO HISTOGRAM 25 25 char 0 NOT IN BINARY longitude_abs NO HISTOGRAM 26 31 long 3 NOT IN BINARY longitude_ew NO HISTOGRAM 32 32 char 0 NOT IN BINARY depth DEPTH.LST 33 35 short 0 69 70 short 0 1 500 1592 mb_magn MB_MAGN.LST 36 38 short 2 14 15 short 2 3 6 683 MB NO HISTOGRAM 39 40 constant 0 NOT IN BINARY flag_isoseismal FLAG_ISO.CST 41 43 char 0 16 18 char 0 BOT FPS 2 intensity INTENSIT.CST 44 44 char 0 19 19 char 0 2 X 236 flags_ngdc FLAGS_NG.CST 45 50 char 0 20 25 char 0 L FT 18 flag_diastrophic FLAG_DIA.CST 45 45 char 0 26 26 char 0 D F 2 flag_tsunami FLAG_TSU.CST 46 46 char 0 27 27 char 0 T T 8 flag_seiche FLAG_SEI.CST 47 47 char 0 28 28 char 0 0 0 0 flag_volcanism FLAG_VOL.CST 48 48 char 0 29 29 char 0 V V 11 flag_non_tectonic FLAG_NON.CST 49 49 char 0 30 30 char 0 L L 2 flag_infrasonic FLAG_INF.CST 50 50 char 0 31 31 char 0 0 0 0 Flinn_Engdahl_region FLINN_EN.LST 51 53 short 0 32 33 short 0 16 620 1960 ms_local_magn MS_LOCAL.LST 54 55 short 1 34 35 short 1 3 7 39 MS NO HISTOGRAM 56 57 constant 0 NOT IN BINARY z_h Z_H.CST 58 58 char 0 36 36 char 0 H Z 13 flag_cultural FLAG_CUL.CST 59 59 char 0 37 37 char 0 C F 873 flag_other FLAG_OTH.CST 60 60 char 0 38 38 char 0 S S 2 magnitude_other NO HISTOGRAM 61 63 short 2 NOT IN BINARY magn_other_source NO HISTOGRAM 64 66 char 0 NOT IN BINARY international_data_exchange_event INTERNAT.CST 67 67 char 0 44 44 char 0 X X 1 flag_depth_control_PDE FLAG_DEP.CST 68 68 char 0 45 45 char 0 D N 109 number_of_stations_or_quality NUMBER_O.CST 69 71 char 0 46 48 char 0 1 501 835 time_authority TIME_AUT.CST 72 72 char 0 49 49 char 0 * Z 924 ml_magn_local ML_MAGN_.LST 73 75 short 2 50 51 short 2 1 6 820 ml_magn_local_scale ML_MAGN1.CST 76 77 char 0 52 53 char 0 DR MS 822 ml_magn_local_authority NO HISTOGRAM 78 80 char 0 NOT IN BINARY latitude LATITUDE.LST NOT IN ASCII 4 7 long 3 0 49 1957 longitude LONGITUD.LST NOT IN ASCII 8 11 long 3 -180 180 1960 depth_negate DEPTH_NE.LST NOT IN ASCII 12 13 short 0 -500 0 1592 magn_other MAGN_OTH.LST NOT IN ASCII 39 40 short 2 2 7 183 magn_other_authority MAGN_OT1.CST NOT IN ASCII 41 43 char 0 BDA WEL 184 ml_magn_local_source ML_MAGN2.CST NOT IN ASCII 54 56 char 0 BJI USG 822 year_decimal YEAR_DEC.LST NOT IN ASCII 71 78 double 10 1868.254 1995.357 1960 ==================================== Format File The format file is a listing of the variable names, types and positions within the binary and ASCII files. The file is composed of two parts - the first section is the format of the ASCII file, the second, the format of the binary file. The ASCII format file *.af must be renamed to *.afm to be used with the Freeform utility. Likewise, the binary format file *.bf must be renamed to *.bfm. The structure of this file is: Field 1: Variable name Field 2: First position of variable in line Field 3: Last position of variable in line Field 4: Type of variable Field 5: Precision of variable **Refer to Freeform user's manual for further information See format file npac.fmt in this directory ==================================== ======================================================== Sample Data A representative sample of data records showing the first 10 lines and the last 10 lines of the ASCII data file(i.e. the .dat file). The first and last 10 records of npac.dat follow ======================================================== EQH 1868040302 19 N1555 W XFT 613 D Z SIG 18680403020000019000N155500W 0 X T 613 D 000SIG BDA 190904101936 45 N165 E 60 016 78 BDA 1 SIG 19090410193600045000N165000E 60 016 C 780SIG BDA 191009090111 45 N170 W 60 016 73 BDA 1 BDA 19130622134952 48 N178 W 60 016 72 BDA 1 ISS 19130622134952048000N178000W 0 016 ISS 19140717070625047500N174000W 0 016 ISS 19150403202936048500N171500W 0 016 ISS 19150816005622048500N179000W 0 016 . . . . BJI 19940201100154719400N155430W 32540MB 61353MS 540BJI 21 PDE 19940201100154519244N155288W 3353 MB 5 61351MS F 560HRV 213H520MDHVO SEA 19940201100912419564N157207W 0 612 30W000DRSEA PDE 19941122051006619342N155113W 5 5 613 F 45H410MDHVO PDE 19950215042203218927N155461W 3138 MB 613 52H400MDHVO PDE 19950309081216219340N155126W 539 MB 3 613 F 36H400MDHVO PDE 19950320082951420018N156591W 5146 MB 4 613 F 53H450MDHVO PDE 19950327160442919351N155229W 2541 MB 613 F 54H410MDHVO PDE 19950503222836119320N155217W 8 4 613 F 50H400MDHVO PDE 19950511134920420072N155331W 2344 MB 6 613 D 71H450MDHVO ==================================== Variable File This file contains statistical information on each of the variables in the data set. The variable file npac.var for this catalog follows ==================================== Input file : npac.bin Input format file: npac.fmt No requested precision, Approximate number of sorting bins = 100 source: 1960 values read minimum: BCI found at record 158 maximum: WEL found at record 242 Summary file: source.cst Histogram data precision: 0, Number of sorting bins: 41 latitude: 1960 values read minimum: 0.000 found at record 533 maximum: 49.000 found at record 14 Summary file: latitude.lst Histogram data precision: 0, Number of sorting bins: 54 longitude: 1960 values read minimum: -179.920 found at record 1028 maximum: 180.000 found at record 1844 Summary file: longitud.lst Histogram data precision: 0, Number of sorting bins: 88 depth_negate: 1960 values read minimum: -500 found at record 1942 maximum: 0 found at record 1 Summary file: depth_ne.lst Histogram data precision: 0, Number of sorting bins: 5 mb_magn: 1960 values read minimum: 0.00 found at record 1 maximum: 6.40 found at record 1333 Summary file: mb_magn.lst flag_isoseismal: 1960 values read minimum: found at record 1 maximum: FPS found at record 1779 Summary file: flag_iso.cst intensity: 1960 values read minimum: found at record 3 maximum: X found at record 1 Summary file: intensit.cst flags_ngdc: 1960 values read minimum: found at record 3 maximum: FT found at record 1 Summary file: flags_ng.cst flag_diastrophic: 1960 values read minimum: found at record 2 maximum: F found at record 1 Summary file: flag_dia.cst flag_tsunami: 1960 values read minimum: found at record 3 maximum: T found at record 1 Summary file: flag_tsu.cst flag_seiche: 1960 values read minimum: found at record 1 maximum: found at record 1 Summary file: flag_sei.cst flag_volcanism: 1960 values read minimum: found at record 1 maximum: V found at record 332 Summary file: flag_vol.cst flag_non_tectonic: 1960 values read minimum: found at record 1 maximum: L found at record 97 Summary file: flag_non.cst flag_infrasonic: 1960 values read minimum: found at record 1 maximum: found at record 1 Summary file: flag_inf.cst Histogram data precision: 0, Number of sorting bins: 9 Flinn_Engdahl_region: 1960 values read minimum: 16 found at record 3 maximum: 620 found at record 790 Summary file: Flinn_En.lst Histogram data precision: 0, Number of sorting bins: 6 ms_local_magn: 1960 values read minimum: 0.0 found at record 1 maximum: 7.1 found at record 1006 Summary file: ms_local.lst z_h: 1960 values read minimum: found at record 1 maximum: Z found at record 1004 Summary file: z_h.cst flag_cultural: 1960 values read minimum: found at record 3 maximum: F found at record 69 Summary file: flag_cul.cst flag_other: 1960 values read minimum: found at record 1 maximum: S found at record 1333 Summary file: flag_oth.cst Histogram data precision: 0, Number of sorting bins: 7 magn_other: 1960 values read minimum: 0.00 found at record 1 maximum: 7.80 found at record 3 Summary file: magn_oth.lst magn_other_authority: 1960 values read minimum: found at record 1 maximum: WEL found at record 234 Summary file: magn_ot1.cst international_data_exchange_event: 1960 values read minimum: found at record 1 maximum: X found at record 1006 Summary file: internat.cst flag_depth_control_PDE: 1960 values read minimum: found at record 1 maximum: N found at record 673 Summary file: flag_dep.cst number_of_stations_or_quality: 1960 values read minimum: found at record 1 maximum: B V found at record 289 Summary file: number_o.cst time_authority: 1960 values read minimum: found at record 2 maximum: Z found at record 1 Summary file: time_aut.cst Histogram data precision: 0, Number of sorting bins: 7 ml_magn_local: 1960 values read minimum: 0.00 found at record 1 maximum: 6.50 found at record 223 Summary file: ml_magn_.lst ml_magn_local_scale: 1960 values read minimum: found at record 1 maximum: MS found at record 1577 Summary file: ml_magn1.cst ml_magn_local_source: 1960 values read minimum: found at record 1 maximum: USG found at record 825 Summary file: ml_magn2.cst Histogram data precision: 0, Number of sorting bins: 79 century_and_year: 1960 values read minimum: 1868 found at record 1 maximum: 1995 found at record 1955 Summary file: century_.lst Histogram data precision: 0, Number of sorting bins: 12 month: 1960 values read minimum: 1 found at record 54 maximum: 12 found at record 14 Summary file: month.lst Histogram data precision: 0, Number of sorting bins: 31 day: 1960 values read minimum: 1 found at record 19 maximum: 31 found at record 66 Summary file: day.lst Histogram data precision: 0, Number of sorting bins: 24 hour: 1960 values read minimum: 0 found at record 10 maximum: 23 found at record 54 Summary file: hour.lst Histogram data precision: 0, Number of sorting bins: 60 minute: 1960 values read minimum: 0 found at record 1 maximum: 59 found at record 26 Summary file: minute.lst Histogram data precision: 0, Number of sorting bins: 60 second: 1960 values read minimum: 0.0 found at record 1 maximum: 59.9 found at record 1656 Summary file: second.lst Histogram data precision: 0, Number of sorting bins: 88 depth: 1960 values read minimum: 0 found at record 1 maximum: 500 found at record 1942 Summary file: depth.lst Histogram data precision: 0, Number of sorting bins: 79 year_decimal: 1960 values read minimum: 1868.2543260474 found at record 1 maximum: 1995.3577422755 found at record 1960 Summary file: year_dec.lst ==================================== The bibliographic file npac.bib for this catalog follows ==================================== This is the NGDC Bibliography for the Oceania Region ---. "Earthquake-Origins in the South-West Pacific in 1910." Transactions of the New Zealand Institute Vol. 44.Bulletin 39 (Hector Observatory) (1912): 139-42. ---. "Seismicity of the South Atlantic." Journal of Geophysical Research Vol. 73.No. 12 (1968): 3807-20. ---. "The Seismicity of the Arctic." Bulletin of the Seismological Society of America Vol. 55.No. 2 (1965): 501-18. ---. "The Seismicity of the Lower South Antilles." Journal for Geophysics Year 6.Book 4 - 7: 361-69. . "Damaging Earthquake Reports for Guam." Xerox Copy, Data file. Hodgson, E. A. "The Seismicity of the Arctic." Journal of the Royal Astronomical Society of Canada Volume XXIV, No. 5.May-June, 1930 (1930): Pages 201-10. Hodgson, J. H. Bath M. Jensen H. Kvale A. Linden N. A. Murphy L. M. Shebalin N. V. Tryggvason E. and Vesanen E. "Seismicity of the Arctic." Annals of the International Geophysical Year Vol. 30: 33-66. Hodgson, J. H. Båth M. Jensen H. Kvale A. Linden N. A. Murphy L. M. Shebalin N. V. Tryggvason E. and Vesanen E. "Seismicity of the Arctic." Reprinted From Annals of the International Geophysical Year Volume XXX--Seismology: Pages 33-66. Hogben, G. "Earthquake-Origins in the South-West Pacific in 1910." Transactions of the New Zealand Institute, Dominion Observatory Volume XLIV.Dominion Observarory Bulletin No. S 4 (1912): Pages 139-42. Keith, A. Hodgson E. A. de Smitt V. P. et. al. "The Grandbanks Earthquake of 1929." Nature, Dominion Observatory, Western Union Telegraph Company, Eastern Section of the Seismological Society of America, Et. Al. (1929-1964): Various. Stover, C. W. "Seismicity of the Indian Ocean." Journal of Geophysical Research Vol. 71.No. 10 (1966): 2575-81. Sykes, L. R. "Seismicity of the South Pacific Ocean." Journal of Geophysical Research Volume 68.No. 21 (1963): Pages 5999. Tams, E. "Die Seismischen Verhältnisse Des Offenen Atlantischen Ozeans." Sonderdruck Aus Gerlands Beiträge Zur Geophysik. Bd. IVIII.Heft 3 (1927): Pages 319-53. ======================================================== Additional Documentation Any other files contributed to or generated by NGDC as documentation for the data base follows. ======================================================== Following is an abbreviated summary of the format for the ASCII version of this file - *.dat. For a more extensive version of this format, please see the file: formtap.txt in /data/supplmnt directory Line Position Field Comments 1-3 Data source Source from which all or most of the data were obtained. 4 B.C. data indicator Minus sign indicates pre- Christian era. 4-12 Date (Universal Positions 4-8 year, 9-10 month, and 11-12 day Time--UT). 13-19 Origin Time Computed, or observed if (Universal Time--UT) controlled explosion with shot timed. Positions 13-14 hour, 15-16 minute, and 17-19 second. Implied decimal between positions 18 and 19. 20-24 Geographic latitude Usually given to three (decimal degrees) decimal places, although this degree of accuracy is not necessarily applicable. Implied decimal between positions 21 and 22. 25 N/S North or South latitude. 26-31 Geographic longitude Usually given to three (decimal degrees) decimal places. Implied decimal between positions 28 and 29. 32 E/W East or West longitude. 33-35 Focal depth (km) See also position 68. 36-38 Body-wave (Mb) Implied decimal between average value positions 36 and 37. Value as determined by *PDE program. 39-40 MB If magnitude in 36-38 is given. 41-43 Isoseismal map, Three-letter abbreviation fault plane indicating the publication solution, or both of an isoseismal (intensity) map in the following publications: USE, United States Earthquakes; *PDE, Preliminary Deter- mination of Epicenters; WEL, New Zealand Seismologoy Report, Wellington, N.Z.; BSS, Bulleting of the Seismological Society of America; ZUR, Zurich, Switzerland; NTR, Nature Magazine. FPS indicates a fault- plane solution was computed. BOT means that both a fault plane solution and an isoseismal map were produced by the U.S. Geological Survey. 44 Maximum intensity Modified Mercalli Scale or converted to MM Scale: 1-9 = I-IX X = X E = XI T = XII See Appendix 5. 45-50 Associated Phenomena 45 Diastrophism code F = Surface faulting. U = Uplift/subsidence. D = Faulting and uplift/ subsidence. 46 Tsunami code T = Tsunami generated. Q = Possible Tsunami. 47 Seiche code S = Seiche. Q = Possible Seiche. 48 Volcanism Code V = Earthquake associated with volcanism. 49 Nontectonic code R = Rockburst. C = Coal bump or rock- burst in coal mine. M = Meteoritic source. E = Explosion -- accidental, con- trolled or suspected. I = Collapse. L = Lights or other such visual phenomena seen. 50 Waves generated code T = T-wave. A = Acoustic Wave. G = Gravity wave. B = Both A and G. 51-53 Flinn-Engdahl geo- As described by Flinn graphic region no. and others (1974). See appendix 6. 54-55 Surface wave (Ms) Implied decimal between avergae value positions 54 and 55. Value determined by PDE program. (IASPEI formula used). 56-57 MS If magnitude in 54-55 is given. 58 Component Z or H Z = Ms computed from component long- period vertical. H = Ms computed from long-period horizontal component. 59 Cultural Effects C, D, F or H in position 59 indicates reported casualties, damage, felt information or earthquake heard, respectively. The notations listed here provide a brief summary of the earthquake effects on populations and buildings. Casualty, damage, or felt reports associated with a particular earthquake do not imply that the effects were noted at the epi- central position. Especially with offshore earthquakes, the maximum intensity may be reported at some distance from the source of the shock. An "F" in this position (felt but no damage reported) having no accompanying intensity (position 44) is likely associated with an intensity of I - III on the Modified Mercalli Scale; however, tha actual intensity may be higher. 60 Unusual Events L = Liquefaction. G = Geyser/fumerol. S = Landsliding, avalanche. B = Sand Blows. C = Ground cracking, not associated with faulting. V = Visual phenomena or lights. O = Olfactory phenomena. M = More than one of the above. 61-63 Other Magnitude Value obtained from several sources; unspec- ified magnitude type but generally Ms (implied decimal between positions 61 and 62). Fractions have been converted to decimal numbers, or encoded as follows: 6 - 6 1/4 = 6.13 6 1/4 = 6.25 6 1/4 - 6 1/2 = 6.38 6 1/2 = 6.50 6 1/2 - 6 3/4 = 6.63 6 3/4 = 6.75 6 3/4 - 7 = 6.88 For any other range, median values are listed. 64-66 Authority for See source codes in magnitude in appendix 4. positions 61-63 67 Special event X = International Date designator Exchange (IDE) earthquake. 68 Depth control A = Assigned. Designator D = Restrained depth based on 2 or more reported pP's identified as such. G = Depth restrained by Geophysicist. N = Held at 33 km (Normal Depth) where data not sensitive to depth for a shallow-focus. S = Depth control aided by use of S-phase data. * = Less well-constrained free-depth solution; 90% confidence it lies within 8.5 and 16 km (used since January 1985). ? = Poorly constrained free depth solution (used since January 1985). 69-71 Number of stations/ Number of P and/or P' Quality Indicators arrivals used in hypo- center solution. Quality Indicators are as listed below: Source Style and Indicators _____________________________________________________________________________ Source Style and Indicators Single-letter designator in position 69 72 Authority for time Blank = Authority same coordinates/other as source (positions quality indicators 1-3). 73-75 Local Magnitude Implied decimal between positions 73 and 74. 76-77 Magnitude scale used If magnitude in 73-75 is given. Generally ML; USGS will use MB. ML = Local magnitude MB = Body-wave magnitude CL = Coda-length magnitude MS = Surface-wave magnitude DR = Duration Magnitude NU = Nuttli Magnitude MW = Moment magnitude (Abe, 1983, 1984) MR = Rautian magnitude (Kondorskaya and Shebalin, 1982) LH = Magnitude Mlh (Kondorskaya and Shebalin, 1982) LG = Lg body-wave magnitude (Nuttli, 1973) SL = Magnitude from Stover and others, 1984 SH = Magnitude from Stover and others, 1984 SA = Magnitude from Stover and others, 1984 SU = Magnitude of unknown origin from Stover and others, 1984 K = Russian Energy class magnitude MC = Reported magnitude of unknown origin MG = Reported magnitude of unknown origin 78-80 Authority for value in 73-75. ========================================================================= END OF DOCUMENTATION FILE =========================================================================