The IDA Network:
An Element of the IRIS
Global Seismographic Network
Development, Operations, and Maintenance
April 1, 1998 – June 30, 1998
IRIS Sub-Award Agreement Number 0237
Quarterly (calendar) Status Report Q2-1998
Submitted July 17, 1998
Jonathan Berger and Peter Davis
Institute of Geophysics and Planetary Physics
Scripps Institution of Oceanography
University of California San Diego
9500 Gilman Drive
La Jolla, CA 92093-0225
The IRIS/IDA Network:
1.Development, Operations and Maintenance
The objective of this contract is the development, operations, and maintenance of the IDA
Seismographic Network, an element of the IRIS Global Seismographic Network, run by the
Institute of Geophysics and Planetary Physics of the Scripps Institution of Oceanography.
Quarterly reports are submitted in accordance with IRIS subaward agreement number 0237.
This report covers work conducted between April 1 - June 30, 1998. NOTE: All
information reflects the state of the network on June 30, 1998.
IDA personnel performed routine operations and maintenance for all 33 IRIS/IDA GSN
stations and one affiliated station (BFO). This includes, but is not limited to, maintaining
contact with host institutions, reviewing agreements with and instructions for station
operators, supplying stations with recording media, assessing performance of station
hardware, diagnosing reported problems, replacing station equipment when required;
repairing returned equipment when required; traveling to stations to perform maintenance
when required; receiving, logging, and unpacking all data, performing quality control and
routine review of all data to assess station performance, reformatting all data, and distributing
data in a timely manner via the IRIS Data Management System.
The status of specific installed stations as of June 30, 1998, are summarized in Table 2
below. Maintenance issues for specific stations are discussed in Section Specific
Maintenance. All stations are operational except ABKT, MSEY, and MSVF.
UPGRADES: A shipment of three new MK7-ISP units for deployment at OBN, KIV and
TLY was sent to EME on May 15th. After the shipment cleared customs, IDA engineers
traveled to Obninsk on June 10th to install the equipment at OBN and train EME personnel in
its installation and use. OBN began operation under the new ISP system on June 18th. EME
personnel installed a new ISP at KIV on July 13th and expect to do the same at TLY in mid-
IDA personnel have assembled systems designated for AAK, ABKT, BRVK and KURK and
are currently testing their performance. When these tests are completed, assembly of units
intended for ARU, LVZ and NRIL will begin.
Site Preparation Updates, Site Surveys, and Communication Upgrades
Mbarara, Uganda (MBAR): A prefabricated recording building and solar power system have
been shipped to the site. IDA engineers will visit Mbarara in mid-August to assemble them
and to oversee drilling. The driller, Waterwell Development Services, Ltd., has identified a
supplier in South Africa capable of providing casing that meets GSN specifications. He
expects to finish the job quickly once that casing can be delivered from South Africa to
Kappang, Sulawesi, Indonesia (KAPI): Interdrill will begin drilling operations on July 19th.
An IDA engineer will travel to the site to monitor operations and see that the borehole meets
GSN specifications. A prefabricated building to house the recording equipment will be
shipped shortly to Indonesia.
Kwajalein Atoll, Pacific Ocean (KWAJ): The US Army commander has endorsed the MOU,
and we are proceeding with site preparations. A prefabricated vault to be used at this site is
under construction. Shipping the building to the site will require two months time.
Santiago Island, Cape Verde (SACV): The drilling company, A. CAVACO of Lisbon, is
constructing a drill rig adapter needed by the local subcontractor to perform the work. When
that equipment is ready and en route to Cape Verde, a date for beginning the drilling will be
fixed. An IDA engineer will visit the site to oversee final operations and confirm the hole is
completed to specifications.
Diego Garcia, Indian Ocean (DGAR): Pete Davis met with representatives of the US Navy
and the British Foreign Office in May and obtained permission to site the station on the
island. We are working with personnel from the Geothermal Programs Office, China Lake
NWC, to arrange a site selection visit.
Wadi Sarin, Oman (WSAR): The Omanis recently reiterated their interest in hosting a GSN
station. The government has made official inquiries of the CTBTO as to the status of this
station in the IMS and expects to review our application in September after it returns from
summer recess. We remain optimistic that this application will be approved.
Eskdalemuir, Scotland (ESK): The BGS completed installation of a 64 kbs dedicated circuit
from BGS headquarters in Edinburgh to a new LAN linking the various facilities at the
Eskdalemuir observatory. IDA will share the cost of this circuit in exchange for a portion of
the bandwidth to connect to the IRIS/IDA station now on the observatory’s LAN.
Lovozero, Russia (LVZ): Per the GSN Manager’s request, we are not pursuing a
communications link between LVZ and OBN via Apatity at this time. We will revisit this
issue with EME in six months.
Mahe, Seychelles (MSEY): IDA engineers will relocate the recording building to a site
adjacent to the wellhead during a maintenance visit beginning July 27th. A prefabricated
building has been shipped to the site, and a local contractor is currently constructing a
concrete pad on which the structure will rest. This change was necessary following the
closing of the US Air Force base in the Seychelles.
Talaya, Russia (TLY): EME has established a communications link to TLY. When the data
logger at that station is upgraded, data will become available via NRTS.
ASCN, BORG, CMLA, EFI, ESK, FFC, HOPE, KIP, MSEY, RAYN, SHEL,WRAB:
Pakistani authorities disconnected the circuit between IDA and NIL through which NRTS
data flows from May 28th – June 13th, the period covering the Pakistani nuclear testing
program. The NRTS workstation and IDA data logger continued to operate throughout the
period. We are working with our NIL hosts to obtain all tape data for that interval. The
Indian nuclear test stimulated the busiest period of autodrm activity we have ever seen.
The NRTS link to JTS is temporarily down pending replacement of the modems at JTS and
OVSICORI. On June 6th, the temperature at RAYN exceeded the operating range of the
spread spectrum radio’s data buffer and damaged the equipment. We hope to restore the
circuit by installing power, telephone lines and air conditioning at the station. Connectivity
to SHEL was lost from May 25th – June 12th due to a fault in the telephone line. The HOPE
NRTS workstation was difficult to contact throughout the quarter. We have worked with the
station operator and with COMSAT to trace the problem and have concluded that an
intermittent fault exists in the INMARSAT ground station. For now, we will continue to
work with the existing equipment and plan on repairing or replacing it in the long term.
NRTS access to MSVF has not yet been established. We are working with the local
operators to trouble-shoot problems with the telephone circuit. See below. During a visit to
Kyrgyzia, KNET support personnel put in place the infrastructure necessary to connect AAK
to the Internet via spread spectrum radio. Once this station is upgraded to the MK7-ISP,
these data will be available via NRTS. We also anticipate that Internet connectivity to NNA
will be interrupted for intervals during the next six months while the Geophysical Institute of
Peru, where the NRTS workstation is physically located, moves to a new office building.
ABKT: Down. On Apr 19th, the local operator installed an NRTS workstation was shipped
to the site. Data from ABKT were telemetered to IDA and Obninsk from Apr 19th – May
21st. On the latter date the power supply failed, and the station has remained down from that
point. We expect the technical problems at ABKT will be resolved only with the installation
of the new ISP upgrade. We are currently trying to determine the extent of administrative
changes within the Turkmenistan Academy of Sciences. When we have established how
these changes affect the station and have completed testing of the upgrade ISP, we will ship
the new equipment.
ASCN: Up. On June 21st the local operator installed a new vault power supply and anti-
aliasing filter unit shipped to the site. Telemetered data indicate the station is again
operational. We are waiting to receive the first tape to be recorded following the change.
CMLA: Up. An IDA field engineer visited the site Apr 15-22 to repair the GPS clock, main
power supply, ARS and modem. The station regained operational status Apr 20th.
COCO: Up. The operator replaced the DAT drive from spares on site on June 15th.
ERM: Up. An IDA field engineer visited the site Apr 4-8 to address ARS performance, repair
a damaged main power supply and replace the Magellan GPS clock. The station was back in
operation on April 6th.
FFC: Up. The operator replaced the DAT drive from spares on site on June 18th.
HOPE: Up. The east-west STS-1 saturated on May 13th. We are working with the operator
to bring the mass back into the correct operating range. Communication to the station
remains problematic. See NRTS section above.
JTS: Up. The operator replaced the DAT drive from spares on site on June 18th. The STS-2
sensors that failed have been shipped back to IDA and are being tested. We are also working
to repair the telemetry link to the station.
KIV: Up. We understand the new ISP was installed July 13th.
KDAK: Up. The operator replaced the DAT drive from spares on site on June 18th.
LVZ: Up. On May 31st EME personnel installed the GPS clock intended to function as a
replacement for the OMEGA clock that operated there until Sept 30th.
MSEY: Down. On June 10th, the local operator installed a replacement ARS shipped to the
site. During the period that the damaged ARS was still in place, a problem developed with
the DAS that was only diagnosable with the new ARS. A replacement DAS will be shipped
to the site within the next week. IDA engineers will visit the site July 27th to construct a new
recording building (see above) and repair the data logger.
MSVF: Down. An IDA engineer visited the site June 17th-30th with the intent of repairing the
RT-305 board within the DAS as well as the GPS clock and also to analyze DAS-ARS
communications problems. After spending less than four hours at the site, local police
requested that he withdraw to Suva for safety reasons. Local villagers who were displaced
when the hydroelectric dam at Monasavu (the MSVF site) was built began a riot to compel
the Fijian government to give them an additional $35 million in compensation. The villagers
constructed barricades around the entrances to the dam and succeeded in burning one
building to the ground. After waiting more than one week for the standoff to be resolved, our
engineer returned to IGPP. We are awaiting word from the MRD that the political crisis has
been resolved and that it is safe to return.
NRIL: Up. The east-west STS-1 saturated on Apr 19th and has not come back into operating
range since. EME personnel attribute this to the deterioration of the pier on which the
sensors rest. Plans are being made to construct a new pier to be used when the data logger is
OBN: Up. IDA engineers visited EME June 10th - 20th to install the new ISP system and
instruct EME personnel in the assembly, operation and maintenance of the new equipment.
The new data logger became operational June 18th. See attached trip report.
PFO: Up. Vacuum under the STS-1 vertical sensor’s bell jar was lost due to a leak in the
jar’s 3-way valve. IDA technicians re-greased the valve on June 5th.
RAYN: Up. See NRTS above. We are working with our Saudi hosts to install power and
telephone to the site. With power, it will be possible to air condition the rooms in which
electronic components operate.
Personnel and Administration
John Unwin joined the IDA engineering group as a Development Technician on January 12th.
Pete Davis attended the annual US Navy/British Foreign Service Diego Garcia
Political/Military talks in London May 5th-7th. Jon Berger attended a meeting of IMS
auxiliary station operators at the USGS, Reston, on June 2nd-3rd.
The Magellan clocks used to replace the OMEGA clocks at the ten stations effected by the
shutdown of the OMEGA system have all been shipped. Table 1 lists the installation dates
for the units and whether we were able to retroactively correct time after the new clock was
The GPS clocks for all five Russian stations cleared customs on Jan 21st. EME reports the
clocks have been installed at OBN, ARU and KIV. EME elected to use the unit designated
for NRIL to instead replace the clock at TLY. At this point, the correction of time at NRIL
may have to await the ISP upgrade. We will inquire of EME whether the Magellan at TLY
can be used at NRIL once they complete the upgrade of TLY in mid-August.
Table 1. OMEGA Clock Replacements
Station Date Installed Data retroactively
AAK Jan 20 Sept 30
ALE Jan 26 Sept 3
ARU Mar 12 Sept 30
BRVK Feb 19 Nov 27¹
ESK Dec 29 Oct 8¹
KIV Apr 15 No repair possible.
KURK Feb 16 No repair possible.
LVZ May 31 No repair possible.
NRIL Not yet installed -
OBN Jan 21 No repair possible.
¹Because the data logger was not reset for some time thereafter, data
from BRVK and ESK were timed to millisecond accuracy until Oct.
27th and Oct. 8th, respectively.
Plans for Next Quarter
Manufacture and assembly of MK7-ISP units for the MK6B - MK7 upgrades will continue.
We expect to complete testing of systems for AAK, ABKT, BRVK and KURK shortly.
When these are finished, we will begin on ARU, LVZ and NRIL, and after that, we will
assemble units for ALE, RPN and a new station.
A maintenance visit to MSEY is scheduled for July 27th. One of the engineers on that trip
will extend his trip to visit MBAR where he will oversee drilling and assemble the
prefabricated recording building and solar array. A similar trip to KAPI is tentatively
scheduled for September.
ISP installation trips to BRVK and KURK are scheduled for August. We are coordinating
with KIS and IVTAN to determine when it would be best to install the AAK system.
Fiscal information regarding expenditures under IRIS subaward number 0162 are attached.
Please note this covers the extension of the previous subaward. Fiscal information regarding
the current subaward was provided April 24th in accord with the schedule specified in the
subaward terms and conditions.
1. Q2 1998 Financial Report for subaward 0162.
Table 2. IDA Station Status on June 30, 1998
Location Code Latitude Longitude Status
Ala-Archa, Kyrgyzstan AAK 42.639N 74.494E Up
Alert, Canada ALE 82.483N 62.400W Up
Alibek, Turkmenistan ABKT 37.9304N 58.1189E Down
Arti, Russia ARU 56.4302N 58.5625E Up
Ascension Island ASCN 7.9327S 14.3601W Up
Borgarnes, Iceland BORG 64.7474N 21.3268W Up
Borovoye, Kazakhstan BRVK 53.058N 70.283E Up
Chã de Macela, Azores CMLA 37.7637N 25.5243W Up
Cocos (Keeling) Islands COCO 12.1901S 96.8349E Up
Mt Kent, East Falkland Islands EFI 51.6753S 58.0637W Up
Easter Island, Chile RPN 27.158S 109.434W Up
Erimo, Japan ERM 42.015N 143.157E Up
Eskdalemuir, Scotland ESK 55.317N 3.205W Up
Flin Flon, Canada FFC 54.72N 101.9783W Up
Hope Point, South Georgia HOPE 54.2836S 36.4879W Up
Las Juntas, Costa Rica JTS 10.2908N 84.9525W Up
Kislovodsk, Russia KIV 43.9562N 42.6888E Up
Kodiak Island, Alaska KDAK 57.7828N 152.5835W Up
Kurchatov, Kazakhstan KURK 50.7154N 78.6202 Up
Lovozero, Russia LVZ 67.8979N 34.6514E Up
Mahe, Seychelles MSEY 4.6737S 55.4792E Down
Monasavu, Fiji MSVF 17.7333S 178.0500E Down
Nana, Peru NNA 11.988S 76.842W Up
Nilore, Pakistan NIL 33.650N 73.2512E Up
Norilsk, Russia NRIL 69.5049N 88.4414E Up
Obninsk, Russia OBN 55.114N 36.569E Up
Pinon Flat, California PFO 33.609N 116.455W Up
Ar Rayn, Saudi Arabia RAYN 23.5225N 45.5302E Up
St Helena, So Atlantic Ocean SHEL 15.9588S 5.7457W Up
Sutherland, S. Africa SUR 32.380S 20.811E Up
Hobart, Tasmania TAU 42.9099S 147.3204 Up
Talaya, Russia TLY 51.681N 103.644E Up
Warramunga Array, Australia WRAB 19.9336S 134.3600E Up
The IRIS/IDA Network:
2.Data Collection Center
Over the second quarter of 1998, DCC personnel received and processed 379 station field
tapes (volumes). This represents an increase of 46 volumes over the previous quarter and
a decrease of 2 volumes from the second quarter last year. The data included tapes, each
spanning approximately one week, from 33 IRIS/IDA stations plus BFO, which is
contributing their data via the IDA DCC. After the data were converted into CSS format,
DCC personnel conducted a quality assessment (QA) and then archived the data on the
IGPP Epoch mass store system. Figure 1 details the time-periods spanned by each
station. Note that at the time of this writing, not all tapes spanning the second quarter
have been received by the DCC. Table 3 indicates the percentage of data volume
recorded by each station calculated for the total number of second quarter station-days
received, processed and QA'ed by the DCC up to the present.
Three stations, ABKT, MSEY and MSVF, were not operating as noted above. Station
uptimes for the quarter are listed in Table 3.
Shipping delinquency was a nagging problem throughout this quarter. No tapes were
received from ABKT and MSVF due to their operational status. ASCN was repaired too
late in the quarter for any tapes to arrive and be processed. No tapes were received from
either KURK or NIL. We have been informed a shipment of NIL tapes covering this
period, except for the two weeks that Pakistan conducted nuclear tests, is now en route to
IDA via FedEx. KURK tape shipments continue to be the most problematic. This may
be related to difficulties we have with sending financial support to the NNC. IDA
engineers will be traveling to Kazakhstan in August to install ISP systems at BRVK and
KURK. Improving tape transfer will certainly be discussed at that time.
IRIS DMC Seed Data Flow
DCC personnel shipped 2702 SEED station-day volumes on 13 SEED formatted DLT
tapes (IDA #496-#510, exclusive of #508-#509) to the DMC during the second quarter.
DCC personnel also shipped two SEED tapes (IDA#508-#509) containing 2816 stations-
days of NRTS data from 1996-97 that fill in gaps in the field tape records. 94% of the
data received by the DCC in this Quarter was QA'd and shipped to DMC (see Figure 2)
within 60 days of the last data-day on the tape (see Table 4). The remaining 6% of data
consisted of late-arriving tapes and problematic data that required additional care in the
Data Problem and Resolution Reports
Data Problem Reports (DPR) and Problem Resolution Reports (PRR) concerning data
from IRIS/IDA stations filed in the second quarter are attached.
Table 3: IRIS/IDA Station Uptime
Station station-days % received % available
AAK 64 89.8 63.1
ABKT 0 0 0.0
ALE 55 92.9 56.2
ARU 71 99.9 77.9
ASCN 0 0 0.0
BFO 75 100 82.4
BORG 44 95.1 46.0
BRVK 61 93.4 62.6
CMLA 67 96.4 71.0
COCO 23 86.4 21.8
EFI 45 84.9 42.0
ERM 71 98.3 76.7
ESK 82 99.6 89.8
FFC 20 82.3 18.1
HOPE 70 96.8 74.5
JTS 50 94.4 51.9
KDAK 78 93.1 79.8
KIV 65 98.6 70.4
KURK 0 0 0.0
LVZ 48 86.8 45.8
MSEY 17 74.7 14.0
MSVF 0 0 0.0
NIL 0 0 0.0
NNA 81 96.4 85.8
NRIL 52 92.9 53.1
OBN 82 97.7 88.1
PFO 88 98.6 95.4
RAYN 59 96.4 62.5
RPN 32 78.2 27.5
SHEL 50 95.7 52.6
SUR 83 100 91.2
TAU 89 100 97.8
TLY 49 94.2 50.7
WRAB 81 99.2 88.3
Table 3: This table indicates in the fourth column the percentage of data
volume recorded by each station calculated for the total number of second
quarter station-days received, processed and QA'ed by the DCC as of the
time of this writing. In the third column is shown the percentage of data
returned for the quarter assuming that station had operated continuously. For
example, ESK recorded data for 99.6% of the 82 station-days delivered to the
DCC and 89.8% of the possible 91 days of recording. This figure will rise as
tapes are received and processed.
Table 4: IRIS/IDA Station-Tape Latency as of 6/30/98
Station total latency total shipping total shipped
received (days) shipped latency within
min max median (median) 60 days
AAK 11 9 18 13 10 21 10
ABKT 0 - - - 0 - 0
ALE 16 19 49 31 12 38 12
ARU 11 23 35 28 11 36 11
ASCN 0 - - - 0 - 0
BORG 13 7 15 10 9 19 9
BRVK 14 13 41 23 14 28 14
CMLA 12 6 17 10 11 17 11
COCO 14 7 85 31 13 28 9
EFI 11 11 64 20 9 30 8
ERM 12 5 20 10 11 17 11
ESK 11 4 17 9 10 17 10
FFC 10 5 21 11 5 21 5
HOPE 22 14 65 37 16 53 12
JTS 10 8 67 26 7 31 6
KDAK 7 7 28 15 5 24 5
KIV 14 17 41 26 11 32 11
KURK 0 - - - 0 - 0
LVZ 11 21 42 26 10 36 10
MSEY 13 9 34 19 8 24 8
MSVF 0 - - - 0 - 0
NIL 0 - - - 0 - 0
NNA 11 16 45 32 11 38 11
NRIL 9 13 50 28 9 33 8
OBN 13 3 13 10 12 16 12
PFO 15 0 24 4 13 12 13
RAYN 14 3 53 29 10 40 10
RPN 11 14 38 25 11 33 11
SHEL 17 25 79 45 17 47 11
SUR 14 6 22 15 14 23 14
TAU 10 8 25 14 10 23 10
TLY 12 24 36 28 12 38 12
WRAB 14 6 22 9 13 18 13
Table 4: This table indicates the number of tapes received by the DCC in the second
quarter on a station-by-station basis. A database is kept such that latency (time in
days between the last data-day recorded on the tape and arrival/shipment at/from
the DCC) can be reported. Columns 3-5 report the minimum/ maximum/ median
number of days it takes for a tape to arrive at the DCC.
We have gathered some statistics from our usage of INMARSAT to communicate with the
IRIS/IDA station HOPE (Hope Point, South Georgia Island). The circuit was operational for
only a small fraction of the quarter, so the statistics reflect activity over only a portion of the
period. We have been working closely with the local operator, the INMARSAT ground
station’s manufacturer and with COMSAT to trace the nature of the problem and have
concluded it is an intermittent failure within the electronics of the ground station itself. We
are exploring long-term hardware solutions but intend to work with the present equipment in
the short term.
There are two reasons IDA generally opens up a connection to HOPE: (1) to service
autodrm data requests such as those generated by SPYDER, and (2) to retrieve state-of-
health data to establish if the system is functioning properly. Fairly extensive log files
are kept of all activity on the router that governs ISDN traffic in and out of IDA, by the
software that retrieves state-of-health data, and of autodrm activity. From the latter two,
it is possible to reconstruct a picture of data transfer between HOPE and node idahub
during this period.
Table 5. INMARSAT Autodrm activity
Date Bytes Duration Transfer rate Cost
transferred (sec) (bytes/sec) ($)
3-Apr 111,202 188 658 $ 22.36
9-Apr 127,181 44 1,837 $ 9.57
Total: 238,383 232 $ 31.93
Average: 116.0 1,248
Table 5 is based on the logs of autodrm activity. Although the logs of autodrm are less
complete than are the others, they can still give us an estimate of the total cost spent
servicing these requests. In both Tables 5 and 6, the number of bytes transferred
represent that volume of data compressed before transfer. In this case, the time listed is
the total time of the call prorated by the autodrm’s portion of the total data transferred.
Generally speaking, state-of-health data are being transferred simultaneously. Logs of
that activity are shown in Table 6. Likewise, the time shown in Table 6 represents the
total time of the call prorated by the state-of-health’s fraction of total data transferred.
Table 6. INMARSAT Dialups to extract state-of-health.
Date Time Duration Bytes Overhead Transfer rate Cost
(sec) transferred (sec) (bytes/sec) ($)
9-Apr 17:18 202 583,807 20 3,208 $ 43.95
Total: 202 583,807 $ 43.95
Average: 20.0 3,208 $ 43.95
Link utilization efficiency can be calculated by summing the average throughput of
Tables 4 and 5 (1248 bytes/sec + 3,208 bytes/sec) and dividing by the theoretical limit for
TCP/IP transactions over the circuit, 7,420 bytes/sec. The average utilization efficiency
over this period was 60%. Measured against the total throughput, 8,000 bytes/sec, the
efficiency comes to 56%.
During this quarter, we made substantial progress in revising the way we handle sending
NRTS data to the DMC. In June, two SEED tapes containing all NRTS data not found
on field tapes for 1996 and 1997 were mailed to the DMC. The first half of 1998 will
Under the present scheme, the original raw IDA data packets can be reconstructed from
NRTS data at the IDA DCC. Therefore, with some minor modifications to our data
processing framework, it should be possible to time these data to the same precision as
field tape data are timed. It is our intention next to modify our NRTS archiving software
to exploit this capability. From that point, NRTS data sent to the DMC will be equivalent
in time quality to all data from IDA field tapes.
As mentioned in a previous quarterly report, we have been working with Steve Malone to
track more carefully the response of IDA stations to SPYDER® requests. By evaluating
these logs, we were able to identify a long-term problem with requests directed to TAU
(Hobart, Tasmania). Apparently, the firewall at the University of Tasmania was rejecting
all email messages generated by swave.iris.washington.edu, possibly because swave was
running a version of sendmail.mx that was too old. We passed this information on to
Steve with the request that he redirect SPYDER® requests for TAU data to idahub. This
has been done, and TAU SPYDER® data are again flowing to the DMC.
The task of installing NRTS on the LISS/NRTS test node at ASL remains uncompleted.
IDA is reviewing its relationship with CARTS and expects to bring this work to a
conclusion within the next quarter.
Figure 1: This figure is a snapshot of time-spans covered by station field tapes received
by the DCC in the second quarter. The gray-scale representation indicates the
approximate percentage of a 24-hour time-period that the station was operating. Note
that all possible data that were recorded during the second quarter may not have been
received and processed yet by the DCC, due to latency inherit in the transfer of data from
the field (c.f. Table 4). In addition, NRTS data may be used to fill in gaps when data
from that source are available.
Figure 2: This figure is a snapshot of time-spans covered by station field tapes received
by the DCC in the second quarter. The two-tone representation indicates whether the
data have been shipped in SEED format to the IRIS DMC. Large data gaps between
station volumes can be due to hardware failure, lost tapes or corrupted tapes. Data gaps
within a station-tape are not shown. The time spans are "approximate" in that the start
and end times are interpreted from the control headers of the second and last data records
from a particular stream. Some of the small data gaps between volumes in Figure 2 are
artifacts of these approximations.
2. Data Problem Reports for 1998 Q2.
SUBJECT: Trip Report
FROM: Todd Johnson
TO: Station History
Date: 22 June 1998
Purpose: To install the new MK7-isp upgrade equipment at Obnisnk. To
assemble and test the TLY and KIV upgrade equipment and to
train local station operators.
The trip to Obninsk began the morning of the 10th of June with a flight
from San Diego to New York. A change of planes in New York then a
direct flight to Moscows Sheremetivo airport. Arrival time in Moscow
was at 11:30 AM with an elapse time of about 17 hours. I was met at the
airport by a representative of the Geophysical Survey group of the
Russian Academy of Sciences who drove me to Obninsk, an unknown
distance taking 2 hours.
Upon arrival at the Institute, I met with Deputy Director Dmitry
Mekhrushev (Dima) and outlined the work that was to be accomplished
during my visit. I was then shown where the equipment was stored and
verified that the number of crates matched what was indicated on the
manifest. All crates had been opened for Customs inspection and the
cardboard boxes containing the Obninsk equipment had been stacked in a
corner. All crates appeared to have arrived in very good condition.
The Obninsk MK7-isp rack and equipment went together qquickly and
easily with littl or no problems. The GPS antenna was mounted on the
roof and the system, with DAS on a short uplink, powered on. All
indications were normal. There was some discussion by the Russians when
the GPS receiver failed to lock after 10 minutes of operation. There
was a move to remove it from the rack, open it up and pull the battery
back-up out, action they felt necessary in order to reset the clocks
memory. After vehemently objecting to this and explaining the present
almanac in the clock was for satellites over San Diego and that lock
would require longer than 10 minutes, they relented. By the next
morning the clock was locked and there was no further discussion on the
The station operators from Kislovodsk, Ura (pronounced Your-ah) and
Sasha, joined me on my second day at the Institute and they assisted me
in the assembly of the Talaya system. It too went together easily and
with no problems. The KIV system was left to Ura and Sasha who attacked
the job with enthusiasm and had little difficulty putting it together.
However, the short data uplink (clock/isp to DAS SIO-B) cable was
missing and was never found. Consequently, the KIV and TLY systems had
to share the short data uplink cable between them during the testing
A day after bringing the KIV system on line there was a failure in the
Main Power Supply which shut down the entire MK7-isp. The main symptom
was that the UPS was sounding an alarm at about one second intervals,
the UPS`s fault light was on and there was nothing on the isp LCD
display. The UPS fault was cleared by disconnecting the loads and
cycling the Run swictch on the front panel. Closer inspection of the
Main Power Supply found that the input to the Astec AC/DC supply was
shorted. In order to continue testing the KIV system, the TLY Main
Power Supply was placed in the KIV rack and will probably end up at
Kislovodsk. Main Power Supply S/N 5573 now has the cover with the KIV
sticker and is in the KIV rack. The bad power supply, S/N 5580, now has
the cover with the TLY sticker on it and is awaiting an Astec AC/DC
At the completion of the testing and software upgrade the OBN system
was rolled into position in the recording room beside the old IDA/IRIS
MK4 data logger. There are two eight pair cables from the recording
room to the vault which enabled installation of the MK7-isp vault
equipment while the MK4 continued to collect seismic data from the STS1
seismometers. The conductors in these two cables are 20 awg or 22 awg
which required the use of an additional stranded pair of 14 awg
conductors to carry the 59 volts down to the vault. Termination boxes
were used at both ends of the uplink to allow ease of connection and to
provide a point to look at the uplink signals without breaking the
The CMG-3T (S/N T3438) and FBA (S/N 44831) were installed on a pier
separate from that which the STS1's are installed. This pier is further
away from the vault entrance but only three feet separate it from the
main pier where the STS1's are located. There is a N/S line scribed
into the pier which made orienting the two seismometers an easy
operation. There is presently no other seismometers on this pier.
The vault is clean, dry and the sand that the STS1 baseplates rest on
is in good condition. Due to time and vault accessibility, the free
period of the STS1's was not checked. However, the bell jar on the
vertical STS1 was removed in order to place dessicant on top of the
Permalloy shield. The bell jar was then replaced and the vacuum
reestablished. During the evacuation process, a Paros, model 6000,
microbarograph was placed in parallel with the STS1-V and data were
taken on a PC (microbarograph) and MK7-isp (STS1-V) to be evaluated
later. A Polarity test was performed by pressing on the South side of
the N/S glass base plate and on the West side of the E/W base plate.
The polarity test on the vertical was accomplished by opening the
stopcock for about 1 second. An inspection of the STS1 electronics
revealed that no modification to the Line Driver boards had been made
for use with the MK4 data logger.
Prior to the Polarity and Random Binary tests on the STS1 seismometers
there was a failure in the Black Box short haul modem on the isp/data
side of the uplink. The failed modem was replaced by the only remaining
one on the KIV short uplink cable. Consequently, this left both TLY and
KIV systems inoperable.
The upgraded OBN station became operational on day 170 of 1998.
There was some confusion as to how to leave the KIV and TLY systems. It
seems that there continue to be Customs issues with this equipment.
Director Strovoit instructed me to put all the KIV and TLY equipment
back in their respective boxes. After I had boxed up most of the TLY
system, Deputy Director Mekhrushev told me that they were to be left
set up for testing purposes. I unboxed and reset up the TLY MK7-isp
system and left both systems intact when I left Obninsk on the 20th of
The MK4 system in its entirety was left for the Russians to use
as they saw fit. There is also a Magellan GPS clock that is connected
to MK4 system which took the place of the Omega clock when that timing
system was shut down.
I found the Obninsk Deputy Director and his sidekick as difficult to
deal with as always. They showed an interest in the technology by
opening up equipment and looking inside as well as times when problems
arose. They didn't however, show a great deal of enthusiasm for how it
all worked. They also requested circuit diagrams for the Magellan
clock, Main Power Supply, Remote (or Vault) Power Supply and the
Amplifier Filter. It was a little embarrassing to tell them that those
diagrams were not available.
A valid point that was raised was how Institute was to provide support
for these stations without proper documentation and no spares. I was
unable to provide them an answer for this question but told them that
this issue would have to be worked out at the higher levels.
On the other hand, the station operators from Kislovodsk were
personable, interested and enthusiastic about the new system. They are
good people and very competant technically. In my conversations with
them, I discovered that the water problem that was described to us did
not involve the STS1 electronics but the Buffer boxes (the BB high and
low gain and Mass position circuits). They also informed me that the
sand that the STS1 glass baseplates are resting on are completely
saturated with water. This is very serious and will require a visit by
IDA personnel to relocate the STS1 seismometers onto Aluminum