DDDDaaaattttaaaa RRRReeeeppppoooorrrrtttt ffffoooorrrr TTTThhhheeee 1111999988888888----88889999 PPPPAAAASSSSSSSSCCCCAAAALLLL BBBBaaaassssiiiinnnn aaaannnndddd RRRRaaaannnnggggeeee PPPPaaaassssssssiiiivvvveeee----SSSSoooouuuurrrrcccceeee SSSSeeeeiiiissssmmmmiiiicccc EEEExxxxppppeeeerrrriiiimmmmeeeennnntttt PPPPaaaarrrrtttt IIII:::: LLLLaaaarrrrggggeeee AAAAppppeeeerrrrttttuuuurrrreeee AAAArrrrrrrraaaayyyy DDDDaaaattttaaaa _s_u_b_m_i_t_t_e_d _b_y _T_h_o_m_a_s _J. _O_w_e_n_s, _U_n_i_v_e_r_s_i_t_y _o_f _S_o_u_t_h _C_a_r_o_l_i_n_a _G_e_o_r_g_e _E. _R_a_n_d_a_l_l, _U_n_i_v_e_r_s_i_t_y _o_f _N_e_v_a_d_a-_R_e_n_o _f_o_r _t_h_e _P_R_O_J_E_C_T _S_C_I_E_N_C_E _T_E_A_M ************ PPPPAAAASSSSSSSSCCCCAAAALLLL DDDDAAAATTTTAAAA RRRREEEEPPPPOOOORRRRTTTT ####99990000----000000001111 ************ ABSTRACT This report describes the data from the 1988-89 PASSCAL Basin and Range Passive Source Seismic Experiment, collected by the triggered large aper- ture array consisting of 7 prototype PASSCAL recorders with 3-component intermediate period seismometers. A total of 214 seismic events with known locations, and many smaller local events without locations are included in this data distribution. Data for- mats, auxiliary information, calibra- tion information, and organization of April 15, 2008 - 2 - the distribution data tape are dis- cussed. April 15, 2008 - 2 - _1. _I_n_t_r_o_d_u_c_t_i_o_n The 1988-89 PASSCAL Basin and Range Passive Source Seismic Experiment consisted of two deployments. The Large Aperture Array of 7 PASSCAL data recorders was deployed from August 17, 1988 until April 29, 1989. The Large Aperture Array used 3- component mid-period sensors, and each site operated indepen- dently in a triggered mode. A Small Aperture Array, consisting of the Lawrence Livermore National Laboratory (LLNL) Configurable Seismic Monitoring System (CSMS), was deployed from August 1988 through October 1988. The Small Aperture Array used 3-component short-period sensors, and operated in a continuous recording mode with digital telemetry to a central recording site. The study area was in the region of the Stillwater Range in Nevada (see Figures 1 and 2), and was chosen to coincide with the center of the crossing refraction profiles of the 1986 PASSCAL Basin and Range Lithospheric Experiment. This location was chosen so that a comparison of lithospheric modeling techniques, principally receiver function modeling, and refraction and reflection modeling, could be compared in a coincident study area. The experiment team consisted of a field crew, and project scientists. The field crew, Randy Kuehnel and Thom Morin, deserve a great deal of credit for the success of the field operation. Their consistent dedication and effort made both array deployments operate as smoothly as possible, and aided greatly in the preliminary data processing. The project April 15, 2008 - 3 - scientists consisted of T.J. Owens, D. McNamara (University of Missouri, now at University of South Carolina), G.E. Randall, K.F. Priestley (both at University of Nevada-Reno), and G. Zandt (at the LLNL Insitute for Geophysics and Planetary Physics). The instrumentation for the Large Aperture Array consisted of 7 prototype PASSCAL data recorders, with 3-component mid- period (Kinemetrics SV-1 and SH-1) seismometers. Sites were con- structed with separate insulated buried vaults for recorders and seismometers, and were powered with batteries recharged with solar panels. Most sites (SUN,NYC,GRN,SHP,CHB,ADR) were placed in locations either directly on or slightly above hardrock. The other sites (FNC,ANT) were chosen based on spatial constraints only. Brief site descriptions are given in Appendix A. Johnson (1977) provides a more detailed summary of the geology of this region. Site locations are given in Table 1. This was the first major experiment to make use of the PASS- CAL recorder, and the recording parameters varied often for test purposes. Typically, each recorder operated in a triggered mode, with some units occasionally operating with an additional low sample rate continuous data stream. The triggered data streams were recorded with sampling rates typically of 20 samples per second, although occasionally 50 and 100 samples per second were recorded. The triggers were STA (Short-term average) to LTA (Long-term average) ratios with the LTA window of 100 seconds, and the STA window 6 seconds. The STA/LTA ratio was initially 2.5, but was increased to 2.8 which successfully lowered the April 15, 2008 - 4 - false trigger rate during the winter months and preserved the data triggering. The triggered data streams typically had pre- event buffers of 30 seconds and an overall record length of 150 seconds. Most of the recording was done in 16 bit mode, although some data was recorded with the 32 bit mode. During the course of the experiment GOES clocks were used at the sites. Clock lock problems existed early in the project but were fixed by mid-December. Table 2 summarizes the dates when GOES clocks were added to each site. Prior to these dates, clocks were set manually to GMT during service visits if clock lock appeared to be a problem. Therefore, data recorded prior to the dates in Table 2 are suitable for single station studies, but are not reliable enough for detailed array analysis. In addi- tion, from Julian Day 097 to 109 and from Days 114 - 119, the clock antenna at Chocolate Butte was uprooted by cattle and therefore the clock was not locked in these time periods. A similar problem occurred twice at Anderson Ranch somewhere between Days 080 and 119. It was temporarily corrected once on Day 094, but users are warned to be wary of the timing at Ander- son Ranch during this period. The instrumentation for the Small Aperture Array consisted of the LLNL CSMS system, with 13 continuously recorded digitally telemetered stations. One station was co-located with a station from the large aperture array (FNC), and operated with mid-period (Kinemetrics SV-1 and SH-1) seismometers. The remaining 12 sta- tions used short period (Geotech S-13) 3 component seismometers. April 15, 2008 - 5 - Time information was derived from an OMEGA clock at the central recording site, and rebroadcast to synchronize the field sites. The field sites used digital telemetry via radio links to pass the 100 sample per second data to the central recording site, where data was continuously recorded onto either optical disk or 8 mm tape for later demultiplexing and analysis. This data report summarizes the data available from the Large Aperture Array. The data from the Small Aperture Array is not yet ready for distribution and will be summarized in Part II of this report at a later date. The standard distribution tape for this experiment is trace data for located seismic events. Supplementary raw data for unlocated events is also available to interested researchers. _2. _D_e_s_c_r_i_p_t_i_o_n _o_f _D_a_t_a _D_i_s_t_r_i_b_u_t_i_o_n The Large-Aperture Array data has been provided to IRIS in three subsets, each of which is a UNIX file structure. The con- tents of the subsets is described below. The entire data distri- bution totals just over 207 Mbytes in size. All of the trace data in this data distribution is in SAC format. SAC is an acronym for "Seismic Analysis Code", a general purpose software package for the manipulation of seismic data developed at Lawrence Livermore National Laboratory (LLNL). It is available through IRIS or LLNL. In this data distribution, we have separated out seismic events from spurious or culturally- induced triggers. Due to our limited duration recording window, April 15, 2008 - 6 - we also eliminated triggers due to teleseismic surface waves that occasionally triggered the stations. After this initial culling of the data, we searched the Quick Determination of Epicenters (QDE) listings obtained through the toll-free modem number of the National Earthquake Information Center (NEIC). Local and regional events not found in the QDEs were often found in the Nevada Regional Catalog distributed by the Seismological Labora- tory of the University of Nevada-Reno. We were able to identify most seismic triggers using this method, however many smaller local events or mine blasts could not be assigned a location from either catalog. These were retained and are distributed in two subsets as part of the "Raw Data Distribution" described below. All events with known loca- tions were assigned an event number and trace data from these events make up the third, and primary, subset of this distribu- tion. This data is termed the "Numbered Event Data" and is described in the next section. _2._1. _N_u_m_b_e_r_e_d _E_v_e_n_t _D_a_t_a A total of 214 separate seismic events with known locations make up the numbered event data. These events are listed in Table 3. Our numbering scheme was as follows: center, tab(|); ll. 001-299|P-wave triggers 701-999|Teleseismic S-wave Triggers 301-599|Other Teleseismic Body Wave Triggers In the cases of an S-wave trigger, the event number assigned was the P-wave trigger number plus 700 and for the other telese- ismic triggers, the event numbers assigned were the P-wave April 15, 2008 - 7 - trigger number plus 300. For example the Fiji Island event of 4/16/89 triggered some sites on the P-wave, PP-wave, and S-wave. These were assigned event numbers 181, 481, and 881 respectively. The numbered event trace data is distributed using the fol- lowing file naming convention: $EX.EVT.STA.C$ where $EX$ is the 2-letter experiment identification code. In this case, the code used was "$lv$" for Lovelock, the nearest town to the array, was used; $EVT$ is the assigned event number, column 1 in Table 3; $STA$ is the 3-letter station abbreviation, column 1 in Table 1; $C$ is the component identifier, $z$ for Vertical component (positive up), $n$ for North component (posi- tive north), or $e$ for East component (positive east). The trace data amplitudes are given in units of microvolts. The event and station latitude, longitude, and depth or elevation as well as the proper component orientations have been entered into the proper SAC header fields. The numbered event data dis- tribution is organized in the following UNIX directory structure: center, tab(|); ccc ccc rnl. Directory|Size|Description Name|(Mb)|of Contents = NV8889_LAA/|72.9|Main Directory 9 _2._1._1. _T_e_l_e_s_e_i_s_m_i_c _D_a_t_a The geographic distribution of teleseismic data is shown in Figure 3. A typical event that triggered for both P- and S-waves is plotted in Figure 4a and b. The NV8889_LAA/tele.std directory contains the teleseismic traces standardized to a sampling rate 9 April 15, 2008 - 8 - of 20 samples/sec and a record length of 150 sec. In tele.std, the mean of each trace has been removed and a Hanning taper applied to the first and last 7.5 sec of each trace. Also, for each event, the traces at all stations recording the event have been synchronized to a common reference time to allow for more accurate array analysis. Some low signal-to-noise ratio traces and events with other quality control problems have been dis- carded from this directory. This directory contains the data used in the research portion of this study. The NV8889_LAA/tele directory contains teleseismic events saved at their original sampling rate and record length. Some data in NV8889_LAA/tele may be found to suffer from the Picket Fence sampling problem described in the next section. _2._1._2. _L_o_c_a_l/_R_e_g_i_o_n_a_l _D_a_t_a The NV8889_LAA/others directory contains all of the trace data for non-teleseismic events recorded by the Large-Aperture Array. Figures 5 and 6 show typical regional and local events. Each trace has the original sampling rate and record length. Since we have not used this data in our research to date, we have not made thorough attempts to cull low signal-to-noise ratio events or other events with data quality problems from this data set. One correctable data quality problem that occurred with some regularity during the experiment was that the PASSCAL data logger occasionally became hung in a mode where it stored a constant of 10 digital counts between every other data point. In these cases, users need only to remove these points from the data April 15, 2008 - 9 - trace. The resulting record is half the normal length, but the actual data has not been corrupted. In SAC, the "decimate 2 filter off" function fixes this problem, if users redefine the sampling interval to the original value after decimation. This problem became known as the "Picket Fence" mode. It was eventu- ally corrected via hardware/software upgrades. _2._2. _C_a_l_i_b_r_a_t_i_o_n The Kinemetrics SV-1 and SH-1 seismometers were carefully calibrated in the laboratory prior to deployment. The SV-1/SH-1 sensors are moving-coil electromagnetic seismometers with a nomi- nal natural period of 5 seconds. Damping resistors were added to the seismometer circuit to obtain a nominal damping of 0.7 criti- cal. After the initial installation and debugging period, a rou- tine calibration procedure was established and applied at each site during the service visits. Each calibration was assigned a number and the file named in the same manner as in Section 2.1, except that the experiment identifier is "lvc" to distinguish it as a calibration pulse from the Lovelock data set. Our calibration procedure used a battery, cable, and resis- tor network to inject a step of current equally into the cali- bration coils of all three seismometers simultaneously. The current was equal for each of the three coils, but unknown, so true amplitude calibration is not available. Kinemetrics docu- mentation lists a nominal calibration coil force constant of 0.12 Newtons/ampere for the SV-1 and 0.08 Newtons/ampere for the SH-1. We obtained the effective mass of 1.36 Kg for the SV-1 and 1.1 kg April 15, 2008 - 10 - for the SH-1 from Kinemetrics by phone. The tabulated observed relative amplitudes in Table 4 should be corrected by multiplica- tion by 1.213 ([1.1/0.08]/[1.36/0.12]) to account for the dif- ferent coils and effective masses of the SV-1 and SH-1 seismome- ters, which accelerate the SV-1 more than the SH-1 for the same calibration current. Calibration pulses were repeated manually for sufficient duration to fill at least one trigger window (150 seconds), and provided multiple calibration pulses per calibration file. A single calibration pulse was cut from each calibration file for analysis. An unpublished code of D.B. Harris of LLNL was used to fit synthetic calibration pulses to the observed pulses. The code uses a grid search followed by a conjugate gradient least squares optimization to find a best fit to the observed calibra- tion pulse's free period, fraction of critical damping, ampli- tude, and bias. Tabulated calibration information consists of free period, fraction of critical damping, and observed amplitude relative to the vertical for each horizontal component. Some calibrations are not reported because the station had excessive noise which degraded the parameter estimation. A few calibra- tions were discarded because we identified instrumental or recording problems with the calibration. The calibration infor- mation for each available calibration is given in Table 4. The parameters did not normally vary significantly at each site unless a seismometer was changed. The calibration data is provided in SAC format in the April 15, 2008 - 11 - NV8889-LAA/calb directory. It is sorted into station subdirec- tories, e.g. all of the Anderson Ranch calibrations are in NV8889_LAA/calb/ADR. Some calibration traces in these directories suffer from the Picket Fence problem described in Section 2.1.2 of this report. _3. _R_a_w _D_a_t_a _D_i_s_t_r_i_b_u_t_i_o_n Since events for which no catalogued location exists may still be of interest to other researchers, we have included sup- plementary data distributions of our raw data. Two subsets are available: 1988 data and 1989 data. The 1988 subset totals 95 Mb and the 1989 data totals 40 Mb. The data is organized in day directories as follows: center, tab(|); ll. RXXX/events|Seismic event traces RXXX/calb|Calibration traces RXXX/inst|Potential instrument prob- lems where $XXX$ is the Julian Day. If no triggers of a certain type occurred on a given day, that subdirectory will not exist. If all three subdirectories are empty, the R$XXX$ directory will not exist. Within each subdirectory, the trace data naming conven- tion is: $sHR.MN.SC.UNIT.DS.C$ where $HR$ is the hour of the first data point in the trace, $MN$ is the minute of the first data point, $SC$ is the second of the first data point, $UNIT$ is the PASSCAL recorder serial number, $DS$ is the Data Stream that recorded the trace, and $C$ is the Channel number, either 1, 2, or 3. Each subdirectory also contains a tab-delimited file (called April 15, 2008 - 12 - event.lst, calb.lst, inst.lst respectively) consisting of 4 fields: Field 1 - Channel 1 trace filename; Field 2 - trigger type indicator; Field 3 - Event number, if applicable, null field otherwise; Field 4 - Pertinent comments by the field crew. Field 2 may include: tele - teleseismic event; loco - local event; regi - regional event; nuke - known underground nuclear explosion; calb - calibration trigger; inst - potential instrument problem; eqke - general undifferentiated seismic event. Some traces in the Raw Data Distribution may suffer from the Picket Fence sam- pling problem described in Section 2.1.2. For convenience, all of the event.lst files have been com- bined into two files, eventlists.1988 and eventlists.1989, in the directory NV8889_LAA/general_info distributed with the numbered event data. In addition, we have included files calblists.1988 and calblists.1989 in this directory to allow correlation of calibration triggers with the numbered calibrations distributed with the numbered event distribution. Also in the general_info directory are database files containing information by site that will allow users to correlate instrument serial numbers to a specific site. A sample entry is: April 15, 2008 - 13 - STATION NO: 07 STATION NAME: Anderson Ranch AKA: adr STATION LATITUDE: 39.972 LONGITUDE: -118.094 ELEVATION: 1520.000 CHANGES: DATE: 09/28/88 TIME: 22:00 INSTRUMENT TYPE: ref SERIAL #: 0027 STATUS: u LTA: 100. STA: 6. STA/LTA: 2.8 PRE-EVENT MEMORY: 30. EVENT RECORD LENGTH: 150. DATA FORMAT: 32 COMMENTS: No GOES clock; usual 20 Hz, 3 channel trigger but no 1 Hz co ntinuous stream. CHANNEL 01: COMPONENT: z SERIAL #: sv-170 +-DIRECTION: u PRE-AMP GAIN: 512 DAMP GAIN FACTOR: 1.00 CHANNEL 02: COMPONENT: n SERIAL #: sh-252 +-DIRECTION: n PRE-AMP GAIN: 512 DAMP GAIN FACTOR: 1.00 CHANNEL 03: COMPONENT: e SERIAL #: sh-260 +-DIRECTION: e PRE-AMP GAIN: 512 DAMP GAIN FACTOR: 1.00 April 15, 2008 - 14 - The data in the R$XXX$ subdirectories give amplitudes in counts. To convert counts to volts, use the formula: where $PAG$ is the preamp gain, $DGF$ is the Damping Gain Factor required due to the manner in which damping resistance was added to the seismometer circuit, and the scale factor $S$ is given by (for 16 bit data) and (for 32 bit data) _4. _D_a_t_a _R_e_p_o_r_t _F_o_r_m_a_t We have included in the directory NV8889_LAA/data_report a complete version of the text in UNIX troff format and the figures in PostScript format. On our Sun Microsystems workstations, the data report may be printed using: eqn nv8889_laa.txt | tbl | ptroff -ms The Figures may be printed on a PostScript printer using: lpr figure*.ps April 15, 2008 - 15 - _5. _A_c_k_n_o_w_l_e_d_g_e_m_e_n_t_s This project could not have been completed without the expertise, enthusiasm, and endless efforts of Jim Fowler, PASSCAL Project Engineer. Technical, logistical and administrative assistance by Tim Ahern, Richard Boaz, Diane DePolo, Wally Nicks, Glen Offield, Sally Owens, Bill Prothero, and Austin Wilson was valuable. This project was supported by IRIS grants to the University of Missouri-Columbia, the University of South Caro- lina, and the University of Nevada-Reno. T.J. Owens was also sup- ported by the UMC Research Council during the Fall of 1988. _6. _R_e_f_e_r_e_n_c_e_s Johnson, M., Geology and mineral deposits of Pershing County, Nevada, Bulletin 89, Nev. Bur. Mines & Geology, 1977. _7. _D_a_t_a _D_i_s_t_r_i_b_u_t_i_o_n The Data referenced in this report may be obtained through: IRIS Data Management Center 8701 Mopac Blvd., Suite 205 Austin, TX 78759 Telephone: (512) 471-0403, 0404, or 0405 April 15, 2008 - 16 - _8. _A_p_p_e_n_d_i_x _A - _L_a_r_g_e _A_p_e_r_t_u_r_e _A_r_r_a_y _S_i_t_e _D_e_s_c_r_i_p_t_i_o_n_s ADR. Located on the western flank of the Stillwater Range on basalt and andesite flow units of Pliocene age. CHB. Located in the Buena Vista Hills in an area underlain by a gabbroic complex of Jurassic age. FNC. Located on the eastern side of the Buena Vista Valley on a westward dipping alluvial fan of Quaternary age. This deposit is characterized by poorly sorted, unconsolidated sands, silts and gravels derived from the adjacent Stillwater Range. Bedrock was estimated to be at a depth of less than 30 meters. GRN. Located in the northeastern portion of the array on the western flanks of the Stillwater Range along vertical pinnacles of highly weathered and fractured, Late Oligocene to Late Miocene, rhyolite. Local rhyolite accumulations occur as thick flows and shallow intrusives associated with plug domes. NYC. Located on the western slope of the Stillwater Range on highly mylonitized phyllite of the upper Triassic Auld Lang Syne Group. SHP. Located on the eastern slope of the Humbolt Range, on a plug of Tertiary basalt. Some seismometer instability due to frost heaving and lack of insulation occurred. This was the only site that was not buried completely. SUN. Located along the eastern slope of the Humbolt Range in a mine that penetrated into thickly bedded upper Triassic limestone April 15, 2008 - 17 - and dolomite of the Dun Glenn formation. ANT. This site was chosen because the array needed a central site to increase wavenumber resolution across the array. We found that the data were of poor quality due to higher frequency reverbera- tions within the thick Quaternary alluvium of the Buena Vista Valley floor. The site was removed in November of 1988 because of low data quality. April 15, 2008 - 18 - center, tab(|); c s s s s c s s s s c s s s s c c c c c c c c c c l n n n l. TABLE 1 = Large Aperture Array Station Locations = 9Station ID|Latitude|Longitude|Elevation|Station Name |(Deg. N)|(Deg. W)|(meters) 9= ADR|39.972|118.094|1520.0|Anderson Ranch ANT|40.113|117.974|1241.7|Antelope CHB|40.032|118.133|1347.0|Chocolate Butte FNC|40.096|117.885|1487.0|Fencemaker Flat GRN|40.218|117.878|1317.0|Granite Hills NYC|40.051|118.007|1475.0|New York Canyon SHP|40.217|118.058|1341.0|Shiprock SUN|40.139|118.099|1335.0|Sunnyside = center, tab(|); c s c s c s l l l l. TABLE 2 = Large Aperture Array Installation Date of Upgraded GOES Clock = 9Station ID|Date 9= ADR|12/13/88 ANT| CHB|01/12/89 FNC|12/03/88 GRN|12/03/88 NYC|12/03/88 SHP|12/20/88 SUN|12/06/88 = April 15, 2008 - 19 - center, expand, tab(|); csssssss csssssss cccccccc cccccccc ccnnnnnl. TABLE 3 = Event Loca- tions = Evt|Date|Origin|Latitude|Longitude|Depth|Mb|Region ID||Time|(Deg)|(Deg)|(Km) _ 001|08/17/88|015911.1|7.658S|107.264E|58|6.0|JAVA. 002|08/17/88|113452.4|26.912S|70.855W|39|5.6|NEAR COAST OF NORTH- ERN CHILE 003|08/17/88|123813.7|27.208S|70.812W|37|5.3|NEAR COAST OF NORTH- ERN CHILE 007|08/17/88|170000.0|37.297N|116.307W|0|5.4|SOUTHERN NEVADA. "KEAR- SARGE" 004|08/20/88|230910.3|26.663N|86.620E|70|6.5|NEPAL- INDIA BORDER REGION. 005|08/21/88|111548.8|23.293N|108.346W|10|4.9|GULF OF CAL- I- FOR- NIA 006|08/21/88|135143.4|42.795S|85.877W|10|5.8|WEST CHILE RISE 008|08/26/88|215323.1|38.810N|118.069W|20||Near Lovelock, NV April 15, 2008 - 20 - 009|08/27/88|012517.7|11.303N|141.455E|33|5.2|WEST CARO- LINE ISLANDS 010|08/27/88|163017.6|15.838S|172.144W|33|6.0|SAMOA ISLANDS REGION 011|08/30/88|122824.9|37.540N|118.353W|5||CALIFORNIA- NEVADA BORDER REGION. 012|08/30/88|180000.1|37.086N|116.069W|0|5.0|SOUTHERN NEVADA. "BULLFROG" 013|08/30/88|190345.0|37.086N|116.069W|0||BULLFROG COL- LAPSE? OT/Location estimated 014|08/31/88|164516.0|31.789N|115.796W|5|4.9|BAJA CAL- I- FOR- NIA. ML 5.1 (PAS). 015|09/01/88|165252.3|17.065N|99.265W|33|5.0|GUERRERO, MEX- ICO 016|09/02/88|102748.5|54.030N|161.491E|47|5.1|NEAR EAST COAST OF KAM- CHATKA 017|09/05/88|061318.7|18.532N|70.391W|33|5.5|DOMINICAN REPUB- LIC REGION. 018|09/07/88|115325.4|30.336N|137.364E|499|6.0|SOUTH OF HONSHU, JAPAN 718|09/07/88|115325.4|30.336N|137.364E|499|6.0|SOUTH OF HONSHU, JAPAN *** S- WAVE 019|09/13/88|005845.9|29.806N|138.364E|447|5.8|SOUTH OF HONSHU, April 15, 2008 - 21 - JAPAN 020|09/14/88|035957.4|49.801N|78.791E|0|6.1|EASTERN KAZAKH SSR 021|09/14/88|221407.6|23.387S|67.945W|124|5.8|CHILE- ARGENTINA BORDER REGION 022|09/15/88|184803.2|1.404S|77.896W|189|5.8|ECUADOR. 722|09/15/88|184803.2|1.404S|77.896W|189|5.8|ECUADOR. *** S- wave 023|09/16/88|000652.9|22.952S|175.413W|33|4.9|TONGA ISLANDS REGION 024|09/16/88|021614.9|20.362S|178.364W|500|5.2|FIJI ISLANDS REGION 025|09/16/88|024535.8|20.170S|177.770W|500|4.7|FIJI ISLANDS REGION 026|09/16/88|062729.0|17.785S|169.065E|33|4.9|VANUATU ISLANDS 027|09/17/88|062014.6|29.900N|114.100W|10|4.4|BAJA, CA from NEIC via phone 028|09/17/88|152353.7|44.910N|152.945E|43|5.3|KURIL ISLANDS REGION 029|09/19/88|025630.7|38.432N|118.320W|5|4.5|CALIFORNIA- NEVADA BORDER REGION. 030|09/19/88|032215.8|38.461N|118.341W|5||CALIFORNIA- NEVADA BORDER REGION. 031|09/19/88|114619.8|38.450N|118.349W|7|2.5|Hawthorne, NV aft- ershock 032|09/19/88|185837.7|23.003S|175.508W|33|5.4|TONGA ISLANDS REGION 033|09/19/88|210145.8|38.478N|118.111W|5||CALIFORNIA- NEVADA BORDER REGION. 034|09/20/88|001609.1|38.937N|118.063W|5||CALIFORNIA- NEVADA April 15, 2008 - 22 - BORDER REGION. 035|09/21/88|095851.8|46.129N|152.142E|38|5.9|KURIL ISLANDS 036|09/21/88|144334.9|41.790N|118.847W|22|2.8|Local near Denio, NV. 037|09/21/88|182955.7|38.460N|118.340W|9|3.2|Local near Hawthorne, NV 038|09/21/88|235926.7|16.073S|173.481W|33|5.5|TONGA ISLANDS 039|09/22/88|105255.0|38.462N|118.340W|12|3.0|Local near Hawthorne, NV 040|09/22/88|222836.3|23.030N|167.860W|10|5.5|HAWAII REGION 041|09/23/88|154855.6|38.957N|118.171W|0|3.5|California/Nevada border 117|09/24/88|043759.8|38.459N|118.343W|0|2.3|California/Nevada border 042|09/26/88|082321.4|35.402N|140.864E|45|5.9|NEAR E COAST OF HONSHU, JAPAN 043|09/28/88|143847.9|38.462N|118.353W|11|2.3|California/Nevada border 044|09/28/88|164810.0|38.898N|117.830W|14|2.5|North of Hawtorne Nevada 195|09/30/88|000404.0|41.535N|121.627W|5||NOT IN QDES LOC EST. BY COM- PARISON W/#045 045|09/30/88|003014.8|41.535N|121.627W|5||NORTHERN CAL- I- FOR- NIA. ML 4.1 046|09/30/88|004004.4|41.534N|121.598W|5||NORTHERN CALIFORNIA April 15, 2008 - 23 - 047|09/30/88|214501.1|19.356S|177.555W|548|5.4|FIJI ISLANDS REGION 747|09/30/88|214501.1|19.356S|177.555W|548|5.4|FIJI ISLANDS REGION *** S- WAVE 048|10/01/88|094324.5|35.305S|106.059W|10|5.6|EASTER ISLAND COR- DIL- LERA 049|10/02/88|160930.0|27.100N|110.100W|10|4.7|GULF OF CAL- I- FOR- NIA from NEIC via phone 050|10/03/88|004557.8|10.227S|161.243E|130|5.5|SOLOMON ISLANDS 051|10/04/88|003410.7|41.420N|121.593W|5||NORTHERN CAL- I- FOR- NIA. ML 3.2 052|10/04/88|153757.7|3.533S|150.437E|33|5.4|NEW IRE- LAND REGION 053|10/08/88|044624.4|18.693S|172.429W|33|6.7|TONGA ISLANDS REGION 753|10/08/88|044624.4|18.693S|172.429W|33|6.7|TONGA ISLANDS REGION *** S- WAVE 054|10/08/88|211420.1|36.098N|117.860W|6||CALIFORNIA- NEVADA BORDER REGION. 055|10/08/88|212606.3|36.098N|117.860W|6||CALIFORNIA- NEVADA BORDER REGION. April 15, 2008 - 24 - 056|10/09/88|080030.1|38.457N|118.313W|5||CALIFORNIA- NEVADA BORDER REGION. 057|10/10/88|055211.6|42.830N|144.230E|63|5.6|HOKKAIDO, JAPAN REGION. 757|10/10/88|055211.6|42.830N|144.230E|63|5.6|HOKKAIDO, JAPAN REGION. S- wave 058|10/10/88|071921.2|23.161S|171.969E|33|5.6|LOYALTY ISLANDS REGION 059|10/10/88|182030.0|28.344S|177.670W|57|6.5|KERMADEC ISLANDS REGION 759|10/10/88|182030.0|28.344S|177.670W|57|6.5|KERMADEC ISLANDS REGION *** S- WAVE 060|10/11/88|133005.1|40.279N|125.632W|10|3.6|OFF COAST OF NORTH- ERN CAL- I- FOR- NIA 061|10/13/88|140000.0|37.089N|116.049W|0|5.9|SOUTHERN NEVADA. *** "DALHART" 062|10/13/88|161807.8|37.089N|116.049W|0|4.3|SOUTHERN NEVADA. *** "DALHART COL- LAPSE" 063|10/17/88|055653.5|51.237N|159.551E|33|5.7|OFF EAST COAST OF Kam- chatka 064|10/17/88|141445.5|38.218N|118.453W|6|2.9|Regional event near Hawthorne, NV April 15, 2008 - 25 - 065|10/17/88|190441.3|38.764N|115.200W|24|3.4|Regional event south of Ely, NV 066|10/18/88|185738.7|40.253N|118.177W|0|2.1|Local mine blast 067|10/18/88|220305.6|38.326W|118.453W|9|3.2|Regional event near Mina, NV 068|10/19/88|000841.2|36.987N|141.701E|49|5.6|NEAR EASTCOAST OF HONSHU JAPAN. 069|10/19/88|074505.0|38.740N|116.437W|5||NEVADA. ML 3.4 (NEIS). 070|10/19/88|134444.8|34.940N|118.735W|5||SOUTHERN CAL- I- FOR- NIA. ML 071|10/19/88|160823.1|37.223N|118.392W|5||CALIFORNIA- NEVADA BORDER REGION 072|10/19/88|224754.0|33.183N|115.583W|5|4.5|SOUTHERN CAL- I- FOR- NIA. Imperial Val- ley 073|10/20/88|173300.7|38.802N|122.735W|5||NORTHERN CAL- I- FOR- NIA. 074|10/22/88|023818.6|37.398N|118.411W|12|3.7|Regional event near Bishop, CA 075|10/22/88|160413.4|49.061N|156.179E|50|5.6|KURIL ISLANDS 076|10/23/88|063745.0|49.120N|156.215E|33|5.6|KURIL April 15, 2008 - 26 - ISLANDS 077|10/23/88|133811.1|49.205N|156.239E|33|5.3|KURIL ISLANDS 078|10/24/88|052637.1|41.257N|118.570W|8|2.8|Northwest of Win- nemucca, NV 079|10/25/88|144321.0|38.707N|123.848W|5||NEAR COAST OF NORTH- ERN CAL- I- FOR- NIA 080|10/26/88|052325.5|38.446N|118.354W|5|3.2|Regional event near Hawthorne, NV 081|10/26/88|141426.2|38.454N|118.358W|8|3.8|Regional event near Mina, NV 082|10/27/88|031632.91|39.029N|117.987W|0|3.5|Local event near Hawthorne,NV. 083|10/27/88|080232.8|38.365N|118.424W|5||CALIFORNIA- NEVADA BORDER REGION. 084|10/27/88|081411.60|38.460N|118.354W|0|2.6|South of Hawthorne,NV 085|10/27/88|083903.29|38.460N|118.359W|0|2.6|South of Hawthorne,NV 086|10/28/88|144930.2|16.198S|174.342W|140|5.4|TONGA ISLANDS 786|10/28/88|144930.2|16.198S|174.342W|140|5.4|TONGA ISLANDS *** S- wave 087|10/28/88|200253.37|37.595N|116.772W|0|3.1|South of Warm Springs,NV 088|10/31/88|020812.5|23.305S|66.665W|204|5.0|JUJUY PROVINCE,ARGENTINA. April 15, 2008 - 27 - 089|11/01/88|224752.43|40.880N|118.691W|0|2.5|Local mine Blast 090|11/03/88|144711.1|13.793N|90.696W|69|5.6|NEAR COAST OF GUATE- MALA 790|11/03/88|144711.1|13.793N|90.696W|69|5.6|NEAR COAST OF GUATE- MALA *** S- wave 091|11/03/88|200329.48|39.393N|119.565W|0|2.8|Local mine blast 092|11/07/88|035002.8|22.179S|175.008E|33|5.6|SOUTH OF FIJI ISLANDS 093|11/09/88|201459.7|36.987N|116.009W|5||CALIFORNIA- NEVADA BORDER REGION 094|11/10/88|050800.1|37.357N|121.868W|5|4.7|CENTRAL CAL- I- FOR- NIA 096|11/20/88|053926.8|33.461N|118.145W|5|5.1|SOUTHERN CAL- I- FOR- NIA. 796|11/20/88|053926.8|33.461N|118.145W|5|5.1|SOUTHERN CAL- I- FOR- NIA. *** S- wave 097|11/21/88|230131.69|40.257N|118.162W|0|1.7|Local mine blast 098|11/22/88|075739.2|37.396N|118.515W|5||CALIFORNIA- NEVADA BORDER REGION 099|11/22/88|145445.76|39.358N|118.466W|0|2.4|Local mine April 15, 2008 - 28 - blast 100|11/23/88|201122.6|38.568N|117.738W|5||11 NEVADA. ML 2.8 (NEIC) 101|11/25/88|234602.9|48.124N|71.246W|20|5.9|SOUTHERN QUE- BEC 102|12/03/88|113825.0|34.151N|118.139W|10|4.5|SOUTHERN CAL- I- FOR- NIA 103|12/04/88|123358.9|39.319N|118.162W|0|3.0|Near Fal- lon Nevada 104|12/05/88|160531.4|15.320S|173.400W|33|6.1|TONGA ISLANDS 105|12/07/88|074124.2|40.949N|44.293E|10|6.2|TURKEY- USSR BORDER REGION 106|12/07/88|074544.2|41.056N|44.481E|10|5.8|WESTERN CAU- CASUS 107|12/07/88|225359.58|41.085N|119.120W|0|2.6|West of Win- nemucca NV. 108|12/08/88|121720.00|40.246N|117.751W|0|2.1|Local mine blast 109|12/08/88|125859.8|6.876N|82.827W|10|5.7|SOUTH OF PANAMA 809|12/08/88|125859.8|6.876N|82.827W|10|5.7|SOUTH OF PANAMA *** S- wave 110|12/09/88|190909.64|38.090N|118.861W|0|2.9|Local mine blast 111|12/10/88|203000.0|37.199N|116.209W|0|5.1|SOUTHERN NEVADA."MISTY ECHO" 112|12/13/88|040138.9|71.067N|7.775W|10|5.7|JAN MAYEN ISLAND REGION April 15, 2008 - 29 - 114|12/16/88|055303.5|33.984N|116.695W|5|4.9|SOUTHERN CAL- I- FOR- NIA 115|12/16/88|095717.4|29.670S|178.000W|33|6.2|KERMADEC ISLANDS 116|12/30/88|174136.95|37.532N|118.403W|0|3.0|Local mine blast 118|12/24/88|042657.5|23.386S|66.392W|223|5.9|JuJuy Pro- vince, Argen- tina 119|01/02/89|015210.4|18.326S|174.548W|122|6.0|TONGA ISLANDS 819|01/02/89|015210.4|18.326S|174.548W|122|6.0|TONGA ISLANDS S- wave 120|01/03/89|044111.2|29.526N|131.454E|33|5.7|RYUKYU ISLANDS REGION 121|01/09/89|050821.0|36.311N|115.115W|5||CALIFORNIA- NEVADA BORDER REGION. 122|01/09/89|134237.2|46.794N|153.733E|33|5.9|KURIL ISLANDS 822|01/09/89|134237.2|46.794N|153.733E|33|5.9|KURIL ISLANDS, S- wave 123|01/11/89|122332.1|44.577N|129.723W|10|4.7|OFF COAST OF ORE- GON 124|01/11/89|155202.5|44.554N|129.653W|10|4.7|OFF COAST OF ORE- GON 125|01/12/89|194740.5|46.694N|153.981E|33|5.6|KURIL ISLANDS 126|01/13/89|180156.2|46.497N|153.662E|33|5.6|KURIL ISLANDS 127|01/14/89|231326.43|39.716N|117.339W|0||Local mine blast 128|01/19/89|065328.0|33.922N|118.629W|10|5.2|SOUTHERN CAL- I- April 15, 2008 - 30 - FOR- NIA. 129|01/20/89|121041.56|39.288N|119.672W|0||Local Mine Blast 130|01/22/89|222018.8|41.742N|144.359E|33|6.0|HOKKAIDO, JAPAN REGION. 131|01/25/89|093056.93|38.459N|118.328W|0||Local Mine Blast 132|01/27/89|083451.9|56.188N|164.440E|33|5.8|KOMANDORSKY ISLANDS REGION 133|01/30/89|040621.0|38.900N|111.600W|10|5.4|UTAH 134|01/31/89|173925.3|22.292N|107.179W|10|5.2|OFF COAST OF CEN- TRAL MEX- ICO 135|02/04/89|192411.2|5.929N|82.808W|33|5.8|SOUTH OF PANAMA 136|02/07/89|040300.5|21.852S|66.931W|179|5.4|SOUTHERN BOLIVIA 137|02/10/89|111526.7|3.03N|126.92E|33|6.0|TALAUD ISLANDS. 437|02/10/89|111526.7|3.0300N|126.920E|33|6.0|TALAUD ISLANDS. 138|02/10/89|200559.2|37.064N|115.976W|0|5.1|SOUTHERN NEVADA. 162|02/10/89| |37.064N|115.976W|0||Collapse from Evt 138 explo- sion? 139|02/13/89|145124.4|57.460N|33.107W|10|5.2|NORTH ATLAN- TIC OCEAN 140|02/13/89|151447.4|57.409N|33.279W|10|5.2|NORTH ATLAN- TIC OCEAN 141|02/14/89|062026.9|10.434S|161.283E|78|6.1|SOLOMON ISLANDS 841|02/14/89|062026.9|10.434S|161.283E|78|6.1|SOLOMON ISLANDS *** S- April 15, 2008 - 31 - wave 142|02/14/89|154353.7|35.067N|119.145W|10||CENTRAL CAL- I- FOR- NIA. 143|02/15/89|053136.3|39.273N|117.331W|5||NEVADA. 144|02/16/89|215037.8|45.327N|151.785E|95|5.7|KURIL ISLANDS 210|02/17/89|012316.2|39.312N|117.428W|0|2.6|Regional 145|02/18/89|071704.0|34.017N|117.733W|6||SOUTHERN CAL- I- FOR- NIA. 211|02/18/89|140245.0|39.226N|117.333W|10|3.3|Nevada Regional 197|02/19/89|120041.9|39.309N|115.939W|10|3.4|Nevada Regional 198|02/20/89|073211.3|39.244N|117.375W|10|2.4|Nevada Regional 199|02/22/89|092859.0|39.256N|117.401W|4|2.9|Nevada Regional 200|02/22/89|094944.6|39.230N|117.338W|0|3.5|Nevada Regional 146|02/22/89|102541.4|56.217N|153.629W|7|5.7|KODIAK ISLAND REGION 147|02/24/89|161500.0|37.128N|116.122W|0|4.4|SOUTHERN NEVADA."KAWICH," 148|02/25/89|112637.7|29.759S|177.918W|47|6.4|KERMADEC ISLANDS 848|02/25/89|112637.7|29.759S|177.918W|47|6.4|KERMADEC ISLANDS *** S- wave 149|02/27/89|151307.0|38.915N|111.674W|10|3.4|UTAH. 150|02/28/89|130157.9|23.086S|61.585W|575|5.5|PARAGUAY 151|03/01/89|024202.2|43.769N|148.985E|44|5.7|KURIL ISLANDS REGION 152|03/02/89|071345.6|18.413N|68.676W|129|5.4|MONA PAS- SAGE. 153|03/06/89|143942.0|35.800N|140.400E|33|5.7|NEAR EAST COAST OF HONSHU, JAPAN 154|03/06/89|221646.0|33.000N|115.600W|10|4.4|SOUTHERN CAL- I- April 15, 2008 - 32 - FOR- NIA 463|03/09/89|023700.5|13.743S|34.298E|33|5.7|MALAWI Trig- gered on PKP 155|03/09/89|140500.0|37.143N|116.067W|0|5.0|SOUTHERN NEVADA "INGOT," 464|03/10/89|214946.1|13.781S|34.226E|33|6.1|MALAWI Trig- gered on PKP 156|03/11/89|050454.3|17.723S|174.798W|175|6.3|TONGA ISLANDS 856|03/11/89|050454.3|17.723S|174.798W|175|6.3|TONGA ISLANDS *** S- wave 157|03/11/89|122145.0|37.881N|116.018W|5||SOUTHERN NEVADA 201|03/12/89|133133.4|40.285N|117.766W|7|2.5|Nevada Regional 202|03/12/89|225659.9|39.860N|119.381W|3|2.2|Nevada Regional 158|03/15/89|233410.7|38.376N|119.353W|5||CALIFORNIA- NEVADA BORDER REGION 203|03/15/89|234207.8|38.404N|119.404W|7|3.4|Nevada Regional 159|03/16/89|093400.5|29.992S|178.119W|57|5.7|KERMADEC ISLANDS 160|03/17/89|193306.9|34.350S|178.650W|44|5.9|SOUTH OF KER- MADEC ISLANDS 204|03/19/89|031918.8|39.356N|120.003W|9|2.5|Nevada Regional 161|03/20/89|010633.1|59.927N|153.718W|127|5.0|SOUTHERN ALASKA. 205|03/25/89|073529.7|39.924N|117.837W|6|2.6|Nevada Regional 206|03/25/89|133530.2|39.236N|117.373W|0|2.7|Nevada Regional 165|03/26/89|180336.3|38.752N|122.595W|5||N CALIF 214|03/30/89|203929.6|19.371S|176.052W|229|5.5|FIJI ISL REGION April 15, 2008 - 33 - 166|04/03/89|174631.3|37.350N|121.868W|5|4.5|CENTRAL CAL- I- FOR- NIA 167|04/05/89|234748.3|21.135S|69.211W|114|5.8|NORTHERN CHILE 867|04/06/89|234748.3|21.135S|69.211W|114|5.8|NORTHERN CHILE S- wave 168|04/06/89|080540.0|19.602S|169.467E|33|6.3|VANUATU ISLANDS 868|04/06/89|080540.0|19.602S|169.467E|33|6.3|VANUATU ISLANDS S- wave 169|04/07/89|133211.6|51.337N|30.008W|10|5.1|NORTH ATLAN- TIC RIDGE 170|04/07/89|200728.2|33.540N|118.006W|5|4.5|SOUTHERN CAL- I- FOR- NIA 171|04/08/89|012220.5|57.251N|143.615W|10|4.9|GULF OF ALASKA 172|04/08/89|030601.4|15.680S|173.004W|33|5.5|TONGA ISLANDS 173|04/09/89|050750.3|51.533N|178.440W|32|5.2|ANDREANOF ISLANDS, ALEU- TIAN IS 174|04/11/89|035638.8|49.387N|159.259E|33|6.3|KURIL ISLANDS REGION 874|04/11/89|035638.8|49.387N|159.259E|33|6.3|KURIL ISLANDS REGION S- wave 175|04/13/89|004311.2|39.488S|75.081W|33|5.9|OFF COAST OF CEN- TRAL CHILE 875|04/13/89|004311.2|39.488S|75.081W|33|5.9|OFF COAST OF CENTRAL April 15, 2008 - 34 - CHILE S- wave 176|04/14/89|125209.2|19.200N|144.860E|33|5.8|MARIANA ISLANDS 177|04/14/89|130247.8|18.052S|178.423W|571|5.4|FIJI ISLANDS REGION 877|04/14/89|130247.8|18.052S|178.423W|571|5.4|FIJI ISLANDS REGION S- wave 207|04/15/89|061407.4|38.155N|117.864W|10|2.9|Local mine blast 178|04/15/89|142641.6|8.430N|61.070W|25|5.8|VENEZUELA. Felt in south- ern 179|04/15/89|203411.5|30.021N|99.321E|33|6.2|SICHUAN PRO- VINCE, CHINA 479|04/15/89|203411.5|30.021N|99.321E|33|6.2|SICHUAN PRO- VINCE, CHINA *** PP Phase 180|04/16/89|105116.6|4.735N|32.671W|10|5.4|CENTRAL MID- ATLANTIC RIDGE 181|04/16/89|194814.9|20.989S|179.034W|611|5.6|FIJI ISLANDS REGION 881|04/16/89|194814.9|20.989S|179.034W|611|5.6|FIJI ISLANDS REGION S- wave 481|04/16/89|194814.9|20.989S|179.034W|611|5.6|FIJI ISLANDS REGION *** PP phase 182|04/18/89|123353.6|23.718S|179.914E|536|5.8|SOUTH OF FIJI ISLANDS April 15, 2008 - 35 - 882|04/18/89|123353.6|23.718S|179.914E|536|5.8|SOUTH OF FIJI ISLANDS S- wave 196|04/19/89|000822.9|31.323S|177.906W|33|5.8|KERMADEC ISLANDS REGION 183|04/19/89|144856.0|17.859N|105.303W|10|5.1|OFF COAST OF JAL- ISCO, MEX- ICO 184|04/19/89|223929.0|37.263N|115.100W|5||SOUTHERN NEVADA 185|04/20/89|080851.5|9.170S|79.034W|64|5.7|OFF COAST OF NORTH- ERN PERU 186|04/20/89|124552.7|38.489N|117.831W|5|4.3|NEVADA 187|04/20/89|225954.9|57.123N|121.950E|33|6.0|EASTERN USSR 887|04/20/89|225954.9|57.123N|121.950E|33|6.0|EASTERN USSR S- wave 188|04/22/89|151545.4|38.165N|117.805W|5||NEV. ML 3.2 189|04/22/89|152312.9|38.162N|117.806W|5||NEV. ML 2.9 190|04/23/89|192110.0|66.918N|156.241W|33|5.7|ALASKA 191|04/25/89|021324.5|30.042N|99.477E|33|6.1|SICHUAN PROV CHINA 491|04/25/89|021324.4|30.042N|99.477E|33|6.1|SICHUAN PROV CHINA *** PP phase 192|04/25/89|142901.1|16.874N|99.411W|23|6.4|NEAR COAST OF GUER- RERO, MEX. 193|04/25/89|171837.9|35.890N|140.414E|71|5.4|NEAR April 15, 2008 - 36 - E COAST OF HONSHU, JAPAN. 194|04/27/89|022005.8|30.694N|140.734E|93|6.0|S OF HONSHU, JAPAN. 894|04/27/89|022005.8|30.694N|140.734E|93|6.0|S OF HONSHU, JAPAN. S- wave 208|04/26/89|204316.2|38.517N|119.268W|10|2.8|Local mine Blast 209|04/26/89|210108.7|38.514N|119.271W|13|2.6|Local Mine Blast 212|04/28/89|074816.0|13.100N|89.700W|33||El Sal- va- dor 213|04/28/89|023425.0|17.800N|105.200W|33||Jalisco, Mex- ico = April 15, 2008 - 37 - center, expand, tab(|); c s s s s s s s s s c s s s s s s s s s c s s s s s s s s s c c c s c s s c s s c c c c c c c c c c c April 15, 2008 - 38 - c c c c c c c c c c c c c c c c c c c l l n n n n n n n n. TABLE 4 = Large Aper- ture Array Seismom- e- ter Cali- bra- tion Param- e- ters = 9||Vert- i- cal Component|East Component|North Component 9 April 15, 2008 - 39 - _ Sta|Date|Free|Fraction|Free|Fraction|Relative|Free|Fraction|Relative Cal ID||Period|Critical|Period|Critical|Ampl.|Period|Critical|Ampl. ||(sec)|Damping|(sec)|Damping||(sec)|Damping| 9= ADR 003|10/18/88|4.92|0.71|4.23|0.64|0.606|4.23|0.66|0.586 ADR 011|10/25/88|4.91|0.71|4.20|0.63|0.593|4.23|0.64|0.572 ADR 018|11/02/88|4.91|0.71|4.23|0.63|0.595|4.21|0.63|0.566 ADR 042|11/17/88|4.99|0.71|4.15|0.61|0.598|4.14|0.63|0.574 ADR 043|11/17/88|5.00|0.71|4.16|0.59|0.587|4.14|0.62|0.577 ADR 058|12/02/88|5.01|0.75|4.23|0.60|0.567|3.99|0.63|0.587 ADR 074|12/06/88|4.85|0.71|4.08|0.62|0.577|4.08|0.63|0.565 ADR 075|12/13/88|5.09|0.70|4.06|0.61|0.619|3.98|0.61|0.616 ADR 093|01/04/89|5.00|0.71|3.98|0.60|0.595|3.92|0.62|0.593 ADR 094|01/04/89|5.00|0.71|3.98|0.60|0.594|3.92|0.62|0.592 ADR 105|01/13/89|5.08|0.70|4.12|0.58|0.573|4.03|0.57|0.577 ADR 106|01/13/89|5.08|0.70|4.12|0.58|0.574|4.06|0.55|0.551 ADR 109|02/07/89|5.14|0.72|4.05|0.59|0.582|3.98|0.61|0.587 ADR 110|02/07/89|4.99|0.71|3.97|0.59|0.583|3.91|0.60|0.591 ADR 117|02/15/89|4.91|0.72|3.99|0.56|0.541|3.92|0.59|0.543 ADR 130|03/01/89|5.00|0.68|4.06|0.59|0.584|4.07|0.60|0.567 ADR 131|03/09/89|5.07|0.70|3.98|0.58|0.606|3.99|0.61|0.586 ADR 138|03/21/89|5.08|0.71|4.07|0.59|0.587|4.07|0.60|0.575 ADR 146|04/04/89|4.85|0.71|3.98|0.60|0.574|3.97|0.63|0.563 ADR 168|04/29/89|4.92|0.71|4.06|0.61|0.585|4.06|0.63|0.575 ADR 169|04/29/89|5.00|0.69|4.14|0.60|0.578|4.14|0.61|0.555 _ ANT 016|10/26/88|5.47|0.80|4.21|0.64|0.412|4.15|0.62|0.549 ANT 021|11/02/88|5.15|0.81|3.84|0.72|0.401|3.81|0.37|0.465 9 April 15, 2008 - 40 - ANT 031|11/08/88|5.61|0.76|3.82|0.69|0.549|3.69|0.66|0.654 _ CHB 004|10/18/88|4.61|0.70|4.59|0.59|0.547|4.76|0.63|0.559 CHB 012|10/26/88|4.68|0.70|4.70|0.59|0.573|4.76|0.64|0.589 CHB 019|11/02/88|4.60|0.72|4.47|0.61|0.589|4.61|0.64|0.577 CHB 025|11/08/88|4.60|0.69|4.53|0.59|0.571|4.54|0.63|0.588 CHB 051|11/20/88|4.53|0.73|4.28|0.58|0.563|4.45|0.61|0.566 CHB 107|01/13/89|4.54|0.68|4.14|0.57|0.611|4.06|0.53|0.553 CHB 132|03/09/89|4.37|0.90|4.15|0.58|0.639|4.11|0.57|0.599 CHB 139|03/21/89|4.54|0.82|4.22|0.59|0.677|4.22|0.58|0.667 CHB 147|04/04/89|4.76|0.81|4.29|0.60|0.713|4.21|0.58|0.711 CHB 148|04/04/89|4.62|0.83|4.31|0.59|0.680|4.24|0.59|0.668 CHB 156|04/19/89|4.61|0.82|4.52|0.59|0.652|4.52|0.57|0.627 CHB 167|04/29/89|4.60|0.81|4.37|0.60|0.684|4.44|0.58|0.648 _ FNC 032|11/08/88|5.15|0.73|4.38|0.61|0.664|4.06|0.74|0.737 FNC 040|11/12/88|5.01|0.77|4.44|0.60|0.582|4.14|0.70|0.628 FNC 055|11/29/88|5.00|0.73|4.27|0.58|0.640|4.14|0.69|0.633 FNC 061|12/03/88|4.92|0.71|4.12|0.59|0.657|4.05|0.67|0.645 FNC 062|12/03/88|4.92|0.72|4.15|0.62|0.672|4.05|0.63|0.627 FNC 067|12/06/88|5.00|0.72|4.13|0.60|0.664|4.00|0.67|0.654 FNC 068|12/06/88|4.99|0.70|4.04|0.58|0.683|3.99|0.68|0.668 FNC 078|12/13/88|4.91|0.75|3.99|0.59|0.669|4.13|0.63|0.577 FNC 079|12/13/88|5.14|0.71|4.13|0.58|0.688|4.14|0.65|0.643 FNC 090|12/20/88|5.07|0.73|4.13|0.58|0.667|4.05|0.62|0.621 FNC 096|01/04/89|5.07|0.76|4.05|0.59|0.658|3.91|0.67|0.663 FNC 100|01/13/89|5.07|0.72|4.05|0.56|0.655|3.93|0.64|0.649 FNC 101|01/13/89|5.08|0.70|4.05|0.58|0.679|4.05|0.61|0.627 April 15, 2008 - 41 - FNC 120|02/15/89|4.99|0.71|3.98|0.57|0.654|3.88|0.66|0.656 FNC 126|02/23/89|4.93|0.71|4.07|0.65|0.724|3.92|0.64|0.643 FNC 127|03/01/89|4.93|0.68|4.08|0.53|0.630|3.92|0.69|0.668 FNC 135|03/09/89|5.06|0.67|4.19|0.55|0.649|4.13|0.63|0.644 FNC 144|03/21/89|4.93|0.71|4.16|0.59|0.645|4.05|0.63|0.627 FNC 153|04/04/89|4.84|0.72|4.07|0.61|0.656|4.00|0.66|0.637 _ GRN 002|10/15/88|4.76|0.71|3.82|0.54|0.452|4.45|0.61|0.466 GRN 009|10/19/88|4.78|0.72|3.81|0.54|0.452|4.47|0.62|0.468 GRN 017|10/26/88|4.78|0.72|3.99|0.57|0.447|4.61|0.63|0.464 GRN 020|11/02/88|4.69|0.71|3.77|0.57|0.463|4.30|0.62|0.490 GRN 033|11/08/88|4.84|0.76|3.74|0.62|0.491|4.52|0.69|0.484 GRN 034|11/08/88|4.70|0.68|3.67|0.55|0.486|4.29|0.60|0.494 GRN 041|11/13/88|4.62|0.64|3.69|0.54|0.461|4.30|0.59|0.472 GRN 044|11/17/88|4.83|0.69|3.50|0.50|0.482|4.14|0.59|0.504 GRN 056|11/30/88|4.67|0.69|3.50|0.51|0.475|3.96|0.58|0.507 GRN 057|11/30/88|4.71|0.64|3.45|0.50|0.476|4.03|0.57|0.505 GRN 064|12/03/88|4.76|0.70|3.38|0.49|0.483|4.06|0.59|0.492 GRN 069|12/06/88|4.69|0.69|3.51|0.50|0.449|4.06|0.59|0.476 GRN 070|12/06/88|4.91|0.68|3.37|0.53|0.526|4.07|0.57|0.510 GRN 076|12/13/88|4.70|0.69|3.52|0.51|0.460|3.92|0.55|0.489 GRN 077|12/13/88|4.69|0.68|3.51|0.49|0.453|3.98|0.54|0.479 GRN 088|12/20/88|4.83|0.71|3.43|0.51|0.484|4.13|0.58|0.484 GRN 089|12/20/88|4.76|0.69|3.44|0.47|0.462|4.13|0.58|0.472 GRN 095|01/04/89|4.70|0.65|3.42|0.52|0.484|4.00|0.63|0.501 GRN 099|01/13/89|4.77|0.73|3.29|0.48|0.463|3.84|0.57|0.498 GRN 113|02/07/89|4.77|0.72|3.37|0.51|0.468|3.98|0.59|0.489 GRN April 15, 2008 - 42 - 114|02/07/89|4.75|0.71|3.35|0.49|0.463|3.92|0.59|0.501 GRN 118|02/15/89|4.68|0.72|3.28|0.49|0.459|3.92|0.59|0.493 GRN 119|02/15/89|4.68|0.72|3.28|0.49|0.459|3.92|0.59|0.493 GRN 137|03/14/89|4.70|0.73|3.53|0.54|0.470|4.07|0.61|0.497 GRN 142|03/21/89|4.78|0.72|3.52|0.50|0.454|4.20|0.59|0.467 GRN 143|03/21/89|4.76|0.71|3.51|0.48|0.450|4.20|0.58|0.479 GRN 151|04/04/89|4.92|0.75|3.51|0.48|0.450|4.15|0.59|0.485 GRN 152|04/04/89|4.62|0.75|3.44|0.51|0.450|4.13|0.61|0.461 GRN 158|04/19/89|4.62|0.68|3.61|0.53|0.475|4.07|0.54|0.479 GRN 163|04/29/89|4.61|0.67|3.49|0.49|0.467|4.15|0.60|0.509 _ NYC 007|10/18/88|5.48|0.75|4.47|0.64|0.627|4.39|0.63|0.669 NYC 015|10/26/88|5.61|0.75|4.11|0.73|0.756|4.31|0.62|0.701 NYC 022|11/03/88|5.55|0.74|4.31|0.64|0.666|4.22|0.62|0.711 NYC 029|11/08/88|5.70|0.72|4.31|0.61|0.676|4.13|0.63|0.759 NYC 030|11/08/88|5.70|0.73|4.30|0.62|0.684|4.23|0.62|0.727 NYC 038|11/12/88|5.45|0.75|4.23|0.62|0.637|4.22|0.59|0.676 NYC 045|11/18/88|5.85|0.72|4.28|0.61|0.699|4.07|0.59|0.756 NYC 046|11/18/88|5.63|0.74|4.13|0.61|0.664|4.13|0.60|0.692 NYC 065|12/06/88|5.60|0.75|4.06|0.59|0.657|3.91|0.59|0.701 NYC 066|12/06/88|5.64|0.67|4.07|0.54|0.669|3.91|0.52|0.702 NYC 080|12/13/88|5.39|0.76|3.91|0.54|0.631|3.83|0.59|0.697 NYC 091|12/20/88|5.38|0.76|3.92|0.58|0.643|3.75|0.58|0.689 NYC 092|12/20/88|5.78|0.68|4.07|0.58|0.727|3.90|0.59|0.753 NYC 097|01/04/89|5.63|0.71|4.00|0.55|0.669|3.77|0.54|0.709 NYC 102|01/13/89|5.31|0.75|3.90|0.55|0.621|3.68|0.52|0.663 NYC 121|02/15/89|5.39|0.77|3.75|0.53|0.631|3.76|0.55|0.650 NYC 124|02/22/89|5.40|0.68|3.90|0.53|0.648|3.68|0.56|0.731 April 15, 2008 - 43 - NYC 125|02/22/89|5.78|0.80|4.14|0.59|0.645|4.08|0.59|0.665 NYC 145|03/21/89|5.78|0.76|4.05|0.59|0.658|3.81|0.55|0.686 NYC 154|04/04/89|5.62|0.60|4.14|0.58|0.740|3.90|0.57|0.782 NYC 155|04/04/89|5.63|0.60|4.14|0.58|0.736|3.90|0.57|0.777 NYC 160|04/19/89|5.29|0.53|4.30|0.60|0.751|4.00|0.59|0.810 _ SHP 001|10/14/88|5.16|0.76|4.61|0.68|0.512|4.29|0.60|0.515 SHP 005|10/18/88|5.08|0.78|4.70|0.64|0.478|4.39|0.60|0.482 SHP 013|10/26/88|5.31|0.76|4.69|0.66|0.505|4.37|0.59|0.507 SHP 035|11/12/88|5.30|0.73|4.52|0.63|0.510|4.22|0.58|0.536 SHP 047|11/18/88|5.15|0.73|4.38|0.63|0.510|4.15|0.59|0.524 SHP 048|11/18/88|5.24|0.71|4.39|0.62|0.528|4.20|0.58|0.531 SHP 054|11/29/88|5.24|0.74|4.16|0.64|0.549|3.97|0.58|0.551 SHP 059|12/03/88|5.25|0.73|4.23|0.66|0.559|3.99|0.55|0.520 SHP 071|12/06/88|5.31|0.71|4.22|0.63|0.573|3.91|0.59|0.580 SHP 081|12/14/88|5.08|0.75|4.21|0.62|0.512|3.91|0.59|0.528 SHP 136|03/13/89|5.08|0.72|4.38|0.63|0.540|4.00|0.55|0.523 SHP 140|03/21/89|5.08|0.69|4.38|0.61|0.538|4.17|0.56|0.521 SHP 149|04/04/89|4.92|0.62|4.47|0.62|0.545|4.23|0.58|0.541 SHP 161|04/19/89|4.61|0.54|4.68|0.67|0.585|4.38|0.56|0.544 SHP 165|04/29/89|4.94|0.68|4.53|0.63|0.527|4.23|0.58|0.532 _ SUN 006|10/18/88|4.92|0.65|4.23|0.65|0.656|4.07|0.62|0.528 SUN 014|10/26/88|4.93|0.65|4.23|0.64|0.653|4.08|0.63|0.531 SUN 023|11/03/88|5.01|0.68|4.20|0.66|0.676|3.99|0.64|0.556 SUN 024|11/03/88|4.92|0.64|4.29|0.63|0.646|3.92|0.64|0.571 SUN 028|11/08/88|4.68|0.72|4.15|0.70|0.616|3.84|0.68|0.544 SUN 036|11/12/88|4.84|0.66|4.13|0.67|0.658|3.92|0.64|0.542 April 15, 2008 - 44 - SUN 037|11/12/88|4.82|0.67|4.15|0.66|0.636|3.99|0.64|0.518 SUN 049|11/18/88|4.93|0.64|4.07|0.65|0.666|4.07|0.65|0.666 SUN 050|11/18/88|4.84|0.68|4.15|0.64|0.624|4.15|0.64|0.624 SUN 052|11/29/88|4.75|0.66|4.07|0.66|0.639|3.99|0.63|0.522 SUN 053|11/29/88|4.92|0.65|4.13|0.63|0.650|3.91|0.61|0.543 SUN 060|12/03/88|4.93|0.65|4.13|0.63|0.644|3.92|0.65|0.548 SUN 072|12/06/88|4.93|0.65|4.00|0.66|0.691|4.06|0.62|0.511 SUN 073|12/06/88|4.82|0.63|4.07|0.65|0.651|3.92|0.63|0.551 SUN 082|12/14/88|4.83|0.67|4.07|0.60|0.634|3.98|0.63|0.536 SUN 083|12/14/88|4.84|0.67|4.07|0.60|0.632|3.99|0.63|0.529 SUN 098|01/05/89|4.99|0.63|3.91|0.61|0.696|4.04|0.58|0.499 SUN 103|01/13/89|5.08|0.62|4.00|0.56|0.645|3.75|0.65|0.611 SUN 104|01/13/89|5.00|0.62|3.84|0.59|0.674|3.84|0.64|0.577 SUN 111|02/07/89|5.01|0.65|3.68|0.57|0.678|3.90|0.61|0.536 SUN 112|02/07/89|4.84|0.67|3.74|0.57|0.618|3.75|0.62|0.530 SUN 122|02/15/89|4.83|0.64|3.82|0.57|0.621|3.81|0.61|0.526 SUN 123|02/15/89|4.85|0.66|3.84|0.57|0.617|3.82|0.60|0.529 SUN 128|03/01/89|4.84|0.64|3.85|0.60|0.652|3.90|0.63|0.532 SUN 129|03/01/89|4.78|0.66|3.92|0.59|0.613|3.91|0.60|0.515 SUN 133|03/09/89|5.01|0.67|4.04|0.58|0.624|3.99|0.60|0.524 SUN 134|03/09/89|4.92|0.65|4.00|0.61|0.638|3.91|0.60|0.538 SUN 141|03/21/89|5.06|0.63|3.84|0.63|0.727|3.75|0.64|0.603 SUN 150|04/04/89|4.92|0.66|3.99|0.59|0.633|3.84|0.63|0.552 SUN 162|04/19/89|4.91|0.65|3.98|0.60|0.637|3.89|0.62|0.548 SUN 166|04/29/89|4.94|0.65|3.89|0.59|0.646|3.92|0.64|0.550 9= 9 April 15, 2008 - 45 - _9. _F_i_g_u_r_e _C_a_p_t_i_o_n_s Figure 1. Basemap of Nevada. Heavy lines show the locations of the 1986 PASSCAL Basin and Range Active-Source Seismic Experi- ment. The 1988-89 Passive-Source Experiment was located in an area with a radius of 20 km around the intersection of the 1986 lines. Figure 2. Expanded map of stations locations. Boxes are the stations of the Large Aperture Array, diamonds are the stations of the Small Aperture Array, and small triangles are the sites of the 1986 Active Source Experiment. Figure 3. Distribution of Teleseismic Events recorded by the Large Aperture Array. Distance increases radially outward, back azimuth increases clockwise. Figure 4A. P-wave trigger for Event 156 recorded by the Large Aperture Array. Figure 4B. S-wave trigger for Event 156 recorded by the Large Aperture Array. Using our numbering scheme, this is event number 856. Trigger occurred 9 minutes, 41 seconds after the P-wave trigger shown in Figure 4A. Figure 5. Trigger for Event 155, NTS shot "INGOT", recorded by the Large Aperture Array. Figure 6. Trigger for Event 208, a Nevada mine blast, recorded by the Large Aperture Array. April 15, 2008