**The seismic network and earthquake catalog of the Hawaiian Volcano
Observatory, 1912-1985**

by Fred W. Klein ^1^, Paul Okubo ^2^, Jennifer E. Nakata ^2^, Robert Y.
Koyanagi ^2^, Jerry P. Eaton ^1^

^1^ USGS, 345 Middlefield Rd. #977, Menlo Park CA 94025

^2^ HVO, Hawaii Volcanoes National Park, HI 96718

DRAFT for the IASPEI \"Inventory of Seismic Network Data\" volume with
CD roms

# ABSTRACT

The Hawaiian Volcano Observatory (HVO) began with a single Bosch-Omori
seismometer in 1912, and in 1999 now operates a modern network of 50
stations. The purpose of the network is multi-fold: 1) to monitor the
active volcanoes Kilauea and Mauna Loa and chart the movement of magma
beneath them with the goal of providing eruption warnings, 2) to study
the role of earthquakes in the process of how the volcanoes work, 3) to
study earthquakes at the periphery of the magma systems caused by
volcano growth and spreading. The latter are large flank and sub-crustal
earthquakes, are driven by volcano growth and form a major shaking
hazard. Earthquake phenomena range from swarms of small M 0-3
volcano-tectonic earthquakes accompanying dike intrusions and eruptions,
to long period events from the deeper magmatic system, to large events
from block sliding of volcano flanks which can reach M 7.9 as it did in
1868. Major milestones in the growth of the network include: 1912:
founding of HVO and construction of the Whitney Vault with mechanical
Bosch-Omori seismometers with gain of 115; 1920\'s: founding of stations
at Hilo and Kona; late 1950\'s: expansion of network with
electromagnetic stations in the Kilauea summit area with smoked paper
recording and gain about 40,000; also establishment or upgrading of
about 8 independently recorded stations including a Wood-Anderson
seismometer in Hilo; 1968: expansion of the network with high gain
(about 100,000) short period seismometers, radio telemetry and
Develocorder recording; 1979: computer digitizing, timing and location
of earthquakes at HVO; 1985: introduction of the CUSP triggered digital
recording and timing system.

# NETWORK SUMMARY

Name: Hawaiian Volcano Observatory (HVO)

Years of operation: 1912 - beyond 2000

Number of stations: 50 in 1999

Number of earthquakes: 17,738 (1912-1959); 107,974 (1960-1998)

Computer file sizes: see decade table

Contact names:

Paul Okubo, Hawaiian Volcano Observatory, 808-967-8802, pokubo@usgs.gov

Fred Klein, USGS Menlo Park, 650-329-4794, klein@usgs.gov

# SUMMARY OF STATIONS AND EARTHQUAKES BY DECADE

Table 1.

+-------+----+---------+--------+------------+------------+----------+
| Years | Nu |         | Number | Catalog    |            | Comp     |
|       | mb |         | of     | size       |            | leteness |
|       | er |         | earth  | (bytes)#   |            |          |
|       | of |         | quakes |            |            | ma       |
|       | st |         |        |            |            | gnitude+ |
|       | at |         |        |            |            |          |
|       | io |         |        |            |            |          |
|       | ns |         |        |            |            |          |
|       | \* |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
|       | S  | Com     |        | Locations  | Phases     |          |
|       | it | ponents |        |            |            |          |
|       | es |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 2  | 4       | 3,153  | \~379K     | none       | 4.5      |
| 12-19 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 3  | 6       | 8,333  | \~725K     | none       | 4.0      |
| 20-29 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 4  | 7       | 1,990  | \~291K     | none       | 3.8      |
| 30-39 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 5  | 9       | 1,539  | \~225K     | none       | 4.0      |
| 40-49 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 12 | 22      | 2,723  | \~398K     | none       | 3.8      |
| 50-59 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 24 | 30      | 12,062 | 1,737K     | 16,816K    | 2.7      |
| 60-69 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 44 | 59      | 41,229 | 6,109K     | 93,759K    | 2.4      |
| 70-79 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 54 | 86      | 33,140 | 5,058K     | 116,329K   | 2.1      |
| 80-89 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+
| 19    | 50 | 78      | 21,545 | 3,197K     | \~69,454K  | 2.3      |
| 90-98 |    |         |        |            |            |          |
+-------+----+---------+--------+------------+------------+----------+

\* at end of decade

\+ The completeness magnitude is approximately for the whole island. The
catalog is much more complete for Kilauea volcano where the network is
denser.

\# Sizes are for Hypoinverse format.

# STATION LIST

Station types:

a analog, electromagnetic, short period, gain 40,000-100,000

e electromechanical Sprengnether, optical recording

m mechanical, gain 100-200

wa Wood-Anderson torsion, gain 2100

s strong motion

Table 2.

Code \--Lat\-\-- \-\--Lon\-\-- Elev Comps Type Dates Name

d min d min m

AHU 19 22.40 155 15.90 1070 3 a 12/01/59-current AHUA

AIN 19 22.50 155 27.62 1524 4 a 4/28/73-current AINAPO

ALO 19 22.00 155 12.80 963 1 a 2/24/69- 5/ 3/70 ALOI CRATER

BPT 21 18.40 158 5.70 10 1 a / /57- / /60 BARBERS POINT, OAHU

CAC 19 29.29 155 55.09 323 1 a 9/20/73-current CAPTAIN COOK

CPK 19 23.70 155 19.70 1038 1 a 11/ 7/67-current CONE PEAK

DAN 19 21.42 155 40.04 3003 1 a 4/27/76-current DANDELION

DES 19 20.20 155 23.30 815 1 a 9/13/57-current DESERT

DESD 19 20.20 155 23.30 815

DHH 21 16.12 157 48.25 137 1

EKO 19 21.80 155 15.30 1009 1 a 5/20/69- 9/29/71 EAST KOAE FAULT

ESR 19 24.68 155 14.33 1177 1 a 4/19/63-current ESCAPE ROAD

ETN 19 25.62 155 15.50 1210 1 a 12/12/59-12/13/59 EATON HOUSE

FEF 19 28.70 155 8.91 691 1 a 5/ 2/89-current FERN FOREST

GLN 19 29.00 155 9.90 732 1 a 5/27/68- 5/ 3/70 GLENWOOD

HAB 19 31.89 154 53.89 92 1 a 10/ 7/80-current HAWAIIAN BEACHES

HAL 20 46.00 156 15.00 2090 3 wa 8/20/53- / 9/92 HALEAKALA, MAUI

HIL 19 43.20 155 5.30 20 2 wa / /57- / 9/92 HILO

HIL 19 43.20 155 5.30 20 1 m,a / /19- / 9/92 HILO

HLP 19 17.96 155 18.63 707 1 a 6/12/61-current HILINA PALI

HPU 19 46.85 155 27.50 3396 1 a 8/18/69-current HALE POHAKU

HSC 20 43.70 156 15.30 3049 1 a 4/14/70-11/16/70 HALEAKALA, MAUI

HSS 19 36.31 155 29.13 2445 3 a 7/ 7/75-current HUMUULA SHEEP STAT.

HTC 19 14.33 155 24.02 381 1 a 3/10/81-current HOT CAVES

HUA 19 41.25 155 50.32 2189 1 a 7/22/71-current HUALALAI

HUL 19 25.13 154 58.72 369 3 a 4/12/77-current HEIHEIAHULU

HVO 19 25.45 155 17.37 1243 1 a 4/ 0/67- 7/ 6/75 UWEKAHUNA (HVO)

KAA 19 15.98 155 52.28 524 1 a 1/ 4/72-current KAAPUNA

KAE 19 17.35 155 7.95 37 1 a 5/ 8/73 2 comp KAENA POINT

KAH 19 24.58 155 4.36 625 1 a 4/21/83- 9/25/86 KAHAUALEA

KAM 20 1.30 155 40.30 815 1 a 1/28/62-10/30/71 KAMUELA

KFA 19 25.25 155 25.18 1579 1 a 3/20/79-current KAOIKI FAULTS

KFB 19 25.25 155 25.18 1579 1 a 8/15/79-11/15/83 KAOIKI FAULTS 2

KGN 19 21.52 154 59.67 30 1 a 9/15/77- 9/20/77 KALAPANA GARDENS

KHU 19 14.90 155 37.10 1939 1 a 8/26/69-current KAHUKU

KII 19 30.56 155 45.90 1841 3 a 7/ 6/75-current KANEKII

KKU 19 53.39 155 20.58 1863 1 a 4/ 1/71-current KEANAKOLU

KLC 19 24.35 155 4.08 659 1 a 9/25/86-current KALALUA CONE

KLK 19 31.20 155 55.30 505 3 a 0/ 0/63- 9/20/72 KEALAKEKUA

KLU 19 27.48 154 55.26 271 1 a 9/15/77-current PUU KALIU

KML 20 1.30 155 40.30 815 1 a 6/ 9/54- 2/ 1/62 KAMUELA

KMM 19 23.47 155 6.98 750 3 a 11/ 8/83- 8/ 4/85 KAMOAMOA

KMO 19 18.50 155 9.60 201 1 a 9/27/66-2/22/69 KEALAKOMO

KOA 19 22.15 155 14.90 1009 1 a 5/24/69- 5/25/69 KOAE FAULTS

KOH 20 7.69 155 46.77 1166 3 a 1/ 0/74-current KOHALA

KON 19 30.80 155 55.10 495 1 a 0/ 0/22-12/ 0/60 KEALEKUA-KONA

KPN 19 20.10 155 17.40 924 1 a 9/21/67-current KIPUKA NENE

KPO 19 30.02 154 50.51 134 1 a 9/17/80-current KAPOHO

KPR 19 16.40 155 26.70 610 1 a 8/18/71- 9/15/77 KAPAPALA RANCH

LAF 19 28.70 154 53.80 189 1 a 5/ 1/70-11/17/70 LAVA FLOW

LOS 19 28.40 154 53.10 159 1 a 4/30/70- 9/ 3/70 LOWER STATION

LUA 19 24.55 155 4.25 622 1 a 12/ 9/75- 4/ 1/83 KALALUA

MAU 19 22.34 155 12.52 994 1 a 1/ 9/74- 1/25/74 MAUNA ULU

MAV 20 46.00 156 15.00 2090 1 a 10/ 0/59- 1/ 0/70 HALEAKALA, MAUI

MKS 19 49.60 155 28.30 4146 1 a 8/ 7/70- 8/ 8/70 MAUNA KEA SUMMIT

MLO 19 29.80 155 23.30 2010 3 m,a 0/ 0/38-current MAUNA LOA

MLX 19 27.60 155 20.70 1475 1 a 9/21/66-current MAUNA LOA X

MOK 19 29.28 155 35.98 4104 1 a 5/22/71-current MOKUAWEOWEO

MPH 19 21.80 155 10.00 866 1 a 7/ 2/61- 2/22/69 MAKAOPUHI

MPP 19 21.02 155 10.20 796 1 a 5/24/69- 5/25/69 MAKAOPUHI

MPR 19 22.07 155 9.85 881 1 a 7/31/69-current MAKAOPUHI

MTV 19 30.25 155 3.75 409 1 a 3/ 4/71-current MOUNTAIN VIEW

M12 19 23.97 155 18.45 1116 1 a 4/24/73- 2/17/74 M12

NAE 19 3.80 155 35.20 205 1 a 9/ 3/54-11/ 0/69 NAALEHU

NAG 19 42.12 155 1.72 18 1 a 6/14/73-current NATIONAL GUARD

NAL 19 3.80 155 35.20 205 3 a 9/ 3/54-3/29/69 NAALEHU

NBY 19 29.70 155 34.80 4005 1 a 3/12/64- 4/11/70 NORTH BAY

NOS 19 23.20 155 18.28 1083 1 a 4/17/73- 7/22/73 NOSE

NPT 19 24.90 155 17.00 1115 3 a 1/ 7/59-current NORTH PIT

OKA 19 29.66 154 55.44 180 1 a

OPA 21 41.45 158 0.70 134 1 a

OTL 19 23.38 155 16.94 1038 1 a 12/ 0/55-current OUTLET

OVE 19 9.21 155 45.92 1378 1 a

PAU 19 22.62 155 13.10 994 3 a 3/15/74-current PAUAHI

PAX 19 29.70 154 56.80 205 1 a 4/24/68- 4/15/70 PAHOA

PHA 19 29.70 154 56.80 205 1 a 1/ 2/60- 4/ 1/69 PAHOA

PHH 19 22.50 155 12.50 1021 1 a 7/29/69- 1/25/74 PUU HULUHULU

PHO 19 29.70 154 56.80 205 1 a 7/ 0/61- 9/ 0/61 PUU HONUAULA

PHO 19 28.90 154 53.40 215 3 a 4/ 4/70-current PUU HONUAULA

PLA 19 32.00 155 27.67 2992 1 a 6/23/77-current PUU ULAULA

PNA 19 14.96 155 25.62 488 1 a 2/17/81- 2/19/81 PUU NAHAHA

POI 19 27.42 154 51.22 16 1 a 10/14/80-current POHOIKI

POL 19 17.02 155 13.47 169 1 a 5/23/73-current POLIOKEAWE PALI

PPA 19 59.00 155 41.50 750 1 a 8/ 5/63- 9/20/64 PUU PA

PPL 19 9.50 155 27.87 35 1 a 8/ 5/63-current PUU PILI

PS1 19 20.70 155 16.70 0 1 a 12/15/65- 1/15/66 PORT STA 1 (KOAE)

PS2 19 19.00 155 13.40 0 1 a 12/15/65- 1/15/66 PORT STA 2 (KOAE)

PS3 19 22.85 155 14.50 0 1 a 12/15/65- 1/15/66 PORT STA 3 (KOAE)

PS4 19 24.50 155 20.20 0 1 a 12/15/65- 1/15/66 PORT STA 4 (KOAE)

PUK 19 23.00 155 6.25 704 1 a 3/22/79-11/ 6/83 PUU KAMOAMOA

RCO 19 24.36 155 37.79 3601 1 a

RIM 19 23.90 155 16.60 1128 1 a 5/24/73-current RIM

RSD 19 27.78 155 16.68 1270 1 a 7/14/87-current RAINSHED

SCA 19 28.20 155 35.08 4048 1 a 8/22/74-12/16/76 SUMMIT CABIN

SHL 19 23.75 155 17.67 1128 1 a 12/28/67- 1/ 5/68 SANDHILL

SPT 18 58.91 155 39.92 244 3 a 4/26/71-current SOUTH POINT

STC 19 23.30 155 7.67 765 3 a 8/ 7/85-current STEAM CRACKS

SWR 19 27.26 155 36.30 4048 1 a 8/22/74-current SOUTHWEST RIFT

TAN 19 27.79 154 58.51 351 1 a 12/ 2/75- 4/ 7/77 TANGERINE

TRA 19 24.91 155 32.96 3207 1 a 7/14/83-current TRAIL

USE 19 25.40 155 17.60 1240 2 e 6/ 0/52-11/16/83 UWEKAHUNA

UEE 19 25.40 155 17.60 1240 3 a 11/21/83-current UWEKAHUNA

WAI 19 51.58 155 39.60 1433 1 a 1/20/84-current WAIKII

WAO 19 3.60 155 36.60 274 1 a 5/ 1/68- 9/30/70 WAIOHINU

WHA 19 19.90 155 2.92 29 1 a 3/ 2/71-current WAHAULA

WHN 19 25.90 155 15.70 1210 2 m 8/ 0/12- 2/ 1/63 WHITNEY VAULT

WHZ 19 25.90 155 15.70 1210 1 m 0/ 0/29- 0/ 0/48 WHITNEY VAULT

WIL 19 28.15 155 35.02 4037 3 a 12/15/76-current WILKES CAMP

WLG 19 25.49 155 15.69 1067 1 a 9/30/71- 6/22/77 WALDRON LEDGE

WOB 19 32.31 155 35.01 3396 1 a 7/14/83-current WEATHER OBSERVATORY

WOO 19 15.08 155 30.12 909 1 a 3/ 8/79-current WOOD VALLEY

WPT 19 24.70 155 17.50 1115 1 a 10/31/62- 9/24/71 WEST PIT

AHU 3 comp since 122079

AIN 3 comp since 8 575

CPK 2 comp 122374-122779

HSS 3 comp since 7/ 7/75

HUL 3 comp since 12/ 9/81

KAE 2 comp 4/21/83-9/25/86

KII 3 comp since 7/ 6/75

KOH 3 comp since 1/26/80

MLO 2 comp since 3/31/75; 3 comp since 4/24/81

MLX 2 comp 11/19/75-2/ 2/80

NPT 3 comp since 12/ 9/80

OTL 2 comp 5/20/75-11/21/79

PAU 2 comp since 5/20/75; 3 comp since 1/ 7/80

PHO 2 comp 2/21/80-12/ 9/81

RIM 2 comp 5/20/75-11/21/79

SPT 3 comp since 11/ 6/80

STC 3 comp since 12/12/85

USE 2 comps are EW and vertical

WIL 3 comp since 2/14/84

# CATALOG AVAILABILITY

The 1912-1959 catalog is from Klein and Wright (2000) who relied largely
on the published Volcano Letter and determined larger magnitudes from
the Honolulu station. The 1912-1959 catalog is available on a CD-rom in
comma delimited format, an Excel spreadsheet, hypo71-2000 format, and
postscript tables of all earthquakes and amplitude readings.

The 1960-1998 catalog is in computer files in Hypoinverse format and is
maintained by HVO. Files are available via anonymous ftp. Sites include
swave.wr.usgs.gov in /ftp/pub/HVO. CNSS format is also available from
the CNSS web site [http://www.cnss.org](http://www.cnss.org/). The
Hypoinverse file format is documented in the same directory structure at
the catalog.

# CATALOG PROBLEMS

*Completeness*. The approximate completeness thresholds for each decade
are listed in the table, and apply for the Big Island as a whole.
Kilauea and Mauna Loa earthquakes are more thoroughly cataloged. For
example the completeness in Kilauea\'s summit area is about 1.2 since
the early 1970\'s. Aftershocks of the M 7.2 Kalapana earthquake from
11/75 until 1/77 are complete to about 2.6 even though completeness in
the same area is normally about 2.0.

*Magnitudes*. Klein and Wright (2000) discuss the calculation of
magnitudes in the 1912-1959 catalog. The 1960-1999 catalog in
Hypoinverse format lists both amplitude and duration magnitudes, and
external surface wave magnitudes where available. The most stable
magnitudes are Wood-Anderson (Hilo station, 1957-10/93), and
Sprengnether seismometer (Uwekahuna, 1957-9/92) amplitude magnitudes.
These are the primary source of amplitude magnitudes during those years
for magnitudes larger than about 2.5. Starting in 1993, amplitude
magnitudes are mostly from a net of 1 hz horizontal seismometers
filtered to simulate Wood-Anderson response and corrected to match
Wood-Anderson magnitudes. Coda duration magnitudes from Develocorder
durations are available during 1975-1997 and are the primary magnitude
for events too small to record on the optical instruments. After the
demise of the Develocorders in 1997, durations are sometimes measured
from paper records and the resultant magnitude entered as an external
magnitudes.

The preferred magnitude is chosen from the three types potentially
available in the order of amplitude, duration and external.

Magnitudes are listed for long period earthquakes (eg. the major Kilauea
swarm in 1989). The seismograms have long durations relative to their
amplitudes, and thus the cataloged duration magnitudes are probably
overestimates. Long period earthquakes are tagged (an \"L\" in the
remarks column of the Hypoinverse format) and their magnitudes should
not be used in any statistical evaluations.

*Locations*. All events prior to 9/59 were located manually by
triangulation with s-p times. Locations in the early catalog typically
incorporate felt and intensity reports, direction estimates from a
single station, association with volcanic activity, or other crude
techniques typical of pre-network seismology. All events from 10/59 and
later were timed and located with Hypoinverse. A crustal model typical
of Kilauea, the south flank and the Kaoiki seismic zone was used. Two
sets of station corrections were used for events near Kilauea summit and
more than 20 km from the caldera.

Following is a list of the largest earthquakes in the combined Hawaiian
catalog. The table is taken from Klein et al. (2000). Swarms of small
earthquakes accompanying eruptions are not included in this list.

Table 3. Magnitude 6 and larger earthquakes in the Hawaiian catalog.

\-\--ORIGIN TIME (HST)\-- -LAT N\-- \--LON W\-- DEPTH PREF MAX

YEAR MON DA HRMN SEC DEG MIN DEG MIN KM RMK MAG INT

1823 JUN 1 2200 0.00 19 21.00 155 1.00 0.00 \* 7.0I IX Kilauea South
Flank (2)

1840 FEB 1 1330 0.00 19 30.00 155 54.00 0.00 \*? 6.1M VII Kona? (2)

1841 APR 6 2345 0.00 20 42.00 156 0.00 0.00 \*? 6.2M VII Maui area? (2)

1844 FEB 18 1830 0.00 0 0.00 0 0.00 0.00 X? 6.2M VII Hawaii? (2)

1852 MAR 31 1615 0.00 0 0.00 0 0.00 0.00 X? 6.1M VII South Hawaii? (2)

1857 JUL 30 0100 0.00 0 0.00 0 0.00 0.00 X? 6.2M VII South Hawaii? (2)

1860 JUL 18 1600 0.00 0 0.00 0 0.00 0.00 X? 6.1M VII South Hawaii? (2)

1861 JUN 1 2030 0.00 0 0.00 0 0.00 0.00 X? 6.1M VII South Hawaii? (2)

1868 MAR 28 1322 0.00 19 14.00 155 30.00 0.00 \* 6.2M VII Hilea (1)

1868 MAR 28 1328 0.00 19 14.00 155 30.00 0.00 \* 7.0I IX Hilea

1868 APR 2 1540 0.00 19 12.00 155 30.00 0.00 7.9I XII Hilea

1868 APR 4 0030 0.00 19 14.00 155 30.00 0.00 \* 6.5I VII Hilea (1)

1868 APR 4 0045 0.00 19 14.00 155 30.00 0.00 \* 6.5I VII Hilea (1)

1868 APR 30 0615 0.00 20 0.00 155 48.00 0.00 \* 6.0I VI Kohala

1868 MAY 24 0.00 0 0.00 0 0.00 0.00 X? 6.2M VII Hawaii? (2)

1869 FEB 18 0.00 0 0.00 0 0.00 0.00 X 6.0M VI South Hawaii (3)

1870 MAR 21 2030 0.00 0 0.00 0 0.00 0.00 X? 6.2M VII South Hawaii? (3)

1870 AUG 7 0413 0.00 21 10.00 156 55.00 0.00 \* 6.0I VI Molokai area

1871 FEB 19 2205 0.00 21 10.00 156 55.00 0.00 \* 6.8I VIII Molokai area

1871 SEP 13 0015 0.00 19 21.00 155 1.00 0.00 \*? 6.0M VII Kilauea South
Flank?

1874 MAY 15 1145 0.00 0 0.00 0 0.00 0.00 X? 6.0M VI Hawaii? (2)

1877 MAY 31 0420 0.00 20 22.00 156 12.00 0.00 \*? 6.2I VI Alenuihaha
Channel?

1881 SEP 30 0453 0.00 20 42.00 156 0.00 0.00 \* 6.3A VIII Maui area

1885 JAN 13 0630 0.00 20 42.00 156 0.00 0.00 \*? 6.0I VI Maui area?

1887 JAN 23 2330 0.00 19 26.00 155 24.00 0.00 \*? 6.5I VIII Kaoiki?

1896 SEP 13 0459 0.00 0 0.00 0 0.00 30.00 \*? 6.0I VI Deep Hawaii? (2)

1905 MAY 3 1607 0.00 19 21.00 155 1.00 0.00 \*? 6.2H VI Kilauea South
Flank?

1906 APR 25 0147 0.00 0 0.00 0 0.00 0.00 X 6.0H V north Hawaii (2)

1908 SEP 20 2015 0.00 19 21.00 155 1.00 0.00 \* 6.7H VII Kilauea South
Flank

1915 MAR 28 0826 0.00 19 26.00 155 24.00 0.00 \*? 6.4H V Kaoiki?

1918 NOV 1 2333 0.00 19 24.00 155 27.00 0.00 6.4A VII Kaoiki

1922 MAY 22 1653 0.00 19 21.00 155 1.00 0.00 \*? 6.0H F Kilauea So.
Flank?(4)

1927 MAR 20 0452 30.00 20 19.00 155 15.00 30.00 \*? 6.8H V Mauna Kea
offshore?

1929 SEP 25 1820 56.00 19 42.00 155 54.00 0.00 6.2H VIII Hualalai

1929 OCT 5 2122 31.00 19 43.00 156 5.00 0.00 \* 6.5S VIII Hualalai

1938 JAN 22 2203 0.00 21 12.00 156 6.00 0.00 6.8S VIII Maui area

1940 JUN 16 2356 49.00 21 0.00 155 18.00 0.00 6.0S VI east of Maui

1941 NOV 18 0256 0.00 20 4.00 155 42.00 43.20 ? 6.1H VI Mauna Kea deep?

1942 FEB 21 0811 0.00 19 32.00 155 28.00 8.00 6.1H VI Mauna Loa NE Rift

1942 FEB 21 0814 0.00 19 32.00 155 28.00 8.00 6.1H VI Mauna Loa NE Rift
(1)

1942 APR 27 2143 0.00 19 32.00 155 28.00 5.00 \*? 6.1A F Mauna Loa NE
Rift?

1950 MAY 29 1517 0.00 19 30.00 156 0.00 0.00 6.3A VII Kona

1951 APR 22 1452 0.00 19 24.50 155 13.30 35.00 6.2A VII Deep Kilauea

1951 AUG 21 0057 0.00 19 30.00 155 57.00 0.00 6.9S VIII Kona

1954 MAR 30 0640 0.00 19 21.00 155 0.00 10.00 6.0H VI Kilauea South
Flank (1)

1954 MAR 30 0842 0.00 19 21.00 155 0.00 10.00 6.4H VII Kilauea South
Flank

1962 JUN 27 1827 14.22 19 23.89 155 27.10 10.18 6.1L VI Kaoiki

1973 APR 26 1026 31.64 19 51.92 155 9.17 38.71 6.2S VIII Mauna Kea deep

1975 NOV 29 0447 40.10 19 20.34 155 0.26 9.15 7.2S VIII Kilauea South
Flank

1983 NOV 16 0613 0.14 19 25.76 155 27.12 10.97 6.7S IX Kaoiki

1989 JUN 25 1727 3.89 19 21.53 155 5.01 9.30 6.2L VII Kilauea South
Flank

Dates and times are Hawaii Standard Time (GMT=HST+10.5 before 6/8/1947,
GMT=HST+10 now). Lat/lon are determined from a) isoseismal maps of Wyss
& Koyanagi (1992), b) the HVO seismic network (since the 1930's), or c)
the center of the geographic region assigned by Klein and Wright (2000)
(these events are marked with an "\*" in the remarks column). A "?" in
the remarks column means there was more uncertainty in estimating the
geographic region. An "X" in the "remarks" column means the geographic
region could not be determined, only generally estimated.

The preferred magnitude was selected from those published, including
those measured by Klein and Wright (2000). The types of preferred
magnitudes are, in order of increasing uncertainty: L local
Wood-Anderson; S teleseismic surface wave; H Honolulu Milne or
Milne-Shaw; A average of two different magnitude types; I from Wyss &
Koyanagi (1992) who used isoseismal areas; and M maximum intensity. The
maximum intensities are from Klein and Wright (2000) who draw on many
sources including Doak Cox (personal communication 1998).

Notes:

\(1\) Aftershock or foreshock (not used in hazard calculation).

\(2\) Early catalog, size or location imprecise (not used in hazard
calculation).

\(3\) Used only for overall South Hawaii rate, not for a specific
region.

\(4\) Felt reports are too sparse to deduce intensities. Amplitude
published in Honolulu station bulletin, but seismogram is lost. Location
assumed from felt reports and coincident East Rift swarm and eruption.
Parameters are too uncertain to use this earthquake in hazard
calculation.

# BIBLIOGRAPHY (partial)

Summaries of network and earthquake data (quarterly 1959-73, yearly
1974-90) describe the processing procedures, crustal model, seismic
network and instrumentation, earthquake maps, lists and counts, and
geologic chronology for the year. For example:

Tomori, A.H., J.S. Nakata, P.G. Okubo, W.R. Tanigawa, and J.P. Tokuuke,
1991, Hawaiian Volcano Observatory Summary 90 part 1, Seismic Data,
January to December 1990, USGS Open File Report 91-578, 79 pp.

Klein, F. W., and Koyanagi, R. Y., 1980, Hawaiian Volcano Observatory
seismic network history 1950-1979, U. S. Geological Open-File Report
80-302. \[A history of the network with an overview of the early network
and detailed station data for the 1950-79 period\].

Klein, F.W., T.L Wright, Catalog of Hawaiian Earthquakes 1823-1959,
2000, USGS Professional Paper 1623, in press. \[An assembly of available
earthquake data and thousands of new magnitude determinations, an
overview of the history of early seismology and instrumentation, and
references to descriptions in publications such as the Volcano Letter\].