130° 131° 132° 133° 134° 135° 136° 137° 130° 131° 132° 133° 134° 135° 136° 137° 6° 5° 4° 3° 2° 1° 0° 6° 5° 4° 3° 2° 1° 0° A R A F U R A S E A T e l u k C e n d e r a w a s i h P e g u n u n g a n M a o k e Epicentral Area J a z i r a h D o b e r a i (B i r d ' s H e a d) Seram Kai Kecil Kai Besar Kep. Kai Kep. Aru T e l u k B e r a n Wokam Biak Yapen S e r a m S e a S e l a t D a m p i r Salawai Misoöl Waigeo 1971 1987 1987 1964 1986 1990 2001 2001 1985 1977 1975 1978 1989 1995 1991 1993 1989 1995 1976 1994 1992 1995 1985 1985 1970 1998 1994 1989 1994 1998 1999 1994 1979 2002 2002 1979 2002 1985 1985 1985 2002 1972 2002 2002 1996 1979 1979 1996 1996 1996 2001 1996 2001 1996 1968 1978 Fer Iso Uta Tum Tip Mar Dosi Nuhu Amar Umuk Nama Wero Tobo Obia Waru Weri Bula Hote Aoem Ajot Saga Gepo Momi BIAK Saba Mala Wari Mega Koor Danar Abean Wokam Oanga Wakia Umari Arbau Argam Urung Kamar Angar Tiari Kufar Wabar Benno Aroba Kokas Degen Tanam Irira Besam Serui Mogoi Baroe Atkri Mijem Sekak Oesin Koffo Gasim Seget Kasim Sauri Worbo Tipin Waiwo Korim Salem Arupi Besir Wakre Rabia Karaum Timuka Wirmaf Aiduna Baraja Tarera Bibiri Kilmun Jarona Mesing Utarom Nabire Bengoi Mariar Ranibo Botare Mageoe Malolo Wadapi Mammeh Mongge Hofuma Lokata Urongi Mokmer Sunder Jeflio Namber Waiboe Kameri Magamo Sadjam Pjodlo Wawesi Poeper Waigual Ohoirin Kilwaer Tamadan Masidan Ngurwel Keawkwa Paraoka Potawai Orawaja Wisalen Kaimana Mirobia Maiwawa Siembra Fak-fak Tambani Tembuni Rawarre Kurunui Airbore Rapaowi Waenggu Atinjoe Warbumi Salebam Klamono Impendi Margeni Samares Meosido Waijaar Selenek Malaboh Tindawi Amboeki Sawaloe Asbakin Makebon Mubrani Emboron Waibeem Lam Lam Warkori Ipirawea Kisalaut Kilbawar Wororomi Werboeam Opdekams Sajengga Kaisweri Tamoelol Sisember Semariak Wakamoek Klasafet Malagots Atuanari Klamesin Adadikam Kepudari Samfeman Sansapor Warmandi Wagailom Wairemah Ojurdjela Ohoitheit Amamapare Hatumeten Tanisepta Manbetalo Kaloekedi Oransbari Geramkato Klamagoen MANOKWARI Temertimer Manggawitu Toena Gain Sipatnanam Len Malaas Saukorrido Ndapurutiri Roefroefoea Gihirkendik Inanwatatan Robookisbia Makalekmela Malaketelik Iweka Temare Walang Tengh Taruata Lama Jaramaniapuka Sigaroi Tapin Karufa Kembala Kampoeng Baroe Manuk Fan Obano Tomoe Wanau Rawas Wandai Kinara Wasian Namboi Mandon Sandow Arnanan RANSIKI Mandori Saunbri Kaironi Koewawin Enarotali Jangketeh Moegoetira Arfak-saba Oerbinasopon Kipia Maparpa 95° 100° 105° 110° 115° 120° 125° 130° 135° 140° 95° 100° 105° 110° 115° 120° 125° 130° 135° 140° 5° 0° 5° 10° 5° 0° 5° Generalized Seismic Hazard of Indonesia I N DI A N O C E A N P A C I F I C O C E A N ARAFURA SEA BANDA SEA JAVA SEA CELEBES SEA ANDAMAN SEA S O U T H C H I N A S E A Map prepared by U.S. Geological Survey National Earthquake Information Center 25 May 2004 Map not approved for release by Director USGS DATA SOURCES EARTHQUAKES AND SEISMIC HAZARD USGS, National Earthquake Information Center NOAA, National Geophysical Data Center IASPEI, Centennial Catalog (1900 - 1999) and extensions (Engdahl and Villaseñor, 2002) HDF (unpublished earthquake catalog) (Engdahl, 2003) Global Seismic Hazard Assessment Program PLATE TECTONICS PB2003 (Bird, 2003) VOLCANOES Smithsonian Institution, Global Volcano Program BASE MAP NIMA and ESRI, Digital Chart of the World USGS, EROS Data Center EARTHQUAKE SUMMARY MAP XXX U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY DISCLAIMER Base map data, such as place names and political boundaries, are the best available but may not be current or may contain inaccuracies and therefore should not be regarded as having official significance. Papua, Indonesia Earthquake Sequence of February 2004 95° 100° 105° 110° 115° 120° 125° 130° 135° 140° 95° 100° 105° 110° 115° 120° 125° 130° 135° 140° 10° 5° 0° 10° 5° 0° 5° Tectonic Setting of Indonesia I N DI A N O C E A N P A C I F I C O C E A N ARAFURA SEA BANDA SEA JAVA SEA CELEBES SEA ANDAMAN SEA S O U T H C H I N A S E A J a v a R i d g e J a v a ( S u n d a ) T r e n c h A r a f u r a S h e l f W e s t C a r o l i n e B a s i n I n v e s t i g a t o r R i d g e W e b e r B a s i n 0 500 1,000 1,500 2,000 250 Kilometers SCALE 1:25,000,000 Mercator Projection 0 500 1,000 1,500 2,000 250 Kilometers SCALE 1:25,000,000 Mercator Projection 120° 125° 130° 135° 140° 120° 125° 130° 135° 140° 5° 0° 5° 0° Seismicity of Eastern Indonesia P A C I F I C O C E A N A R A F U R A S E A B A N D A S E A C E L E B E S S E A F L O R E S S E A M a k a s sa r S t r ai t M o l u c c a S e a S e r a m S e a M o l u c c a s We b e r B a si n Seram Halmahera Kep. Aru Kep. Tanimbar Buru N E W G U I N E A P e n g u n un g a n M a o ke Celebes 0 200 400 600 800 100 Kilometers SCALE 1:12,000,000 Mercator Projection SCALE 1:2,500,000 Mercator Projection EXPLANATION Main Shock #1 5 February 2004 Main Shock #2 7 February 2004 Main Shock #3 8 February 2004 Post-Mainshock Activity 5 - 6 February 2004 7 February 2004 8 February - 20 March 2004 Aftershock Magnitude Classes M < 3.5 3.5 - 3.9 4.0 - 4.4 4.5 - 4.9 5.0 - 5.4 5.5 - 5.9 Earthquakes 1964 - 2002 0 - 69 km 70 - 299 Magnitude Classes 4.0 - 4.4 4.5 - 4.9 5.0 - 5.4 5.5 - 5.9 6.0 - 6.4 6.5 - 6.9 Generalized Plate Boundaries Continental Convergent Continental Rift Continental LL Transform Oceanic Convergent Subduction Volcano PAPUA, INDONESIA 5 February 2004 21:05:04.76 UTC 3.615° S., 135.538°E. Depth 17 km Mw = 7.0 (HRV) This earthquake occurred in the sparsely populated eastern Indo- nesian province of Papua, a mountainous and jungle- clad area of western New Guinea. The epicenter of this earthquake was lo- cated approximately 25 km from Nabire, a coastal town of about 26,000 people. Unofficial reports placed the death toll at 37, with 682 injured and 2,678 structures damaged. Local roads, an airport runway, and nine bridges were damaged as well as two pipelines at an oil refinery nearby. The earthquake also caused minor injuries and damage at two other towns, Enarotali and Manokwari. PAPUA, INDONESIA 7 February 2004 02:42:35.43 UTC 4.003° S., 135.023° E. Depth 10 km Mw = 7.3 (USGS) This earthquake occurred approximately 30 hours after and about 70 km southwest of an M7.0 shock on 5 February 2004 that killed at least 37 people in and near the town of Nabire. The epicenter of this latest earthquake is in a particularly remote area; consequently, reports of casualties and damage emerging from the region are expect- ed to be incomplete; however, additional damage was reported in Nabire. DISCUSSION These earthquakes occurred in a region considered to have the most complex present-day tectonics on Earth. In the area surrounding Irian Jaya (the western half of New Guinea), four major tectonic plates, the Australian, Sunda, Philippine Sea, and Caroline plates, sandwich half a dozen proposed microplates. The interactions between these micro- plates produce all possible styles of faulting. These particular earth- quakes ruptured strike-slip faults near the boundary of the Bird's Head plate and the recently proposed Maoke plate. REFERENCES Bird, P., 2003, An updated digital model of plate boundaries: Geochem. Geophys. Geosyst., v. 4, no. 3, pp. 1027- 80. Engdahl, E.R. and Villaseñor, A., 2002, Global Seismicity: 1900 - 1999, chap. 41 of Lee, W.H.K., and others,eds., International Earthquake and Engineering Seismology, Part A: New York, N.Y., Elsevier Academeic Press, 932 p. Engdahl, E.R., Van der Hilst, R.D., and Buland, R.P., 1998, Global teleseismic earthquake relocation with improved trav- el times and procedures for depth determination: Bull. Seism. Soc. Amer., v. 88, p. 722-743. ON-LINE NEWS RESOURCES ABC News http://abcnews.go.com/wire/World/ Arizona Central News http://www/azcentral/com/news/ Channel News Asia http://www.channelnewsasia.com/stories/ Radio Australia http://www.abc.net.au/ra/ 0 50 100 150 200 25 Kilometers EXPLANATION Seismic Hazard 0.0 - 0.2 m/sec² 0.2 - 0.4 0.4 - 0.8 0.8 - 1.6 1.6 - 3.2 3.2 - 4.3 Plate Boundary Continental Convergent Continental Rift Continental LL Transform Continental RL Transform Oceanic Convergent Oceanic Spreading Oceanic LL Transform Oceanic RL Transform Subduction Volcano Seismic hazard is expressed as peak ground acceleration (PGA) on firm rock, in meters/sec², expected to be exceeded in a 50-yr period with a probability of 10 percent. LARGEST EARTHQUAKES IN THE EPICENTRAL AREA 1964 - 2002 YR MO DY LAT LON DEPTH MAG 1964 4 23 -5.420 133.939 6.1 6.4 1968 7 29 -0.291 133.499 32.7 6.1 1970 11 8 -3.418 135.624 2.3 6.2 1971 9 16 -5.971 130.697 133.0 6.4 1972 12 4 -1.513 136.639 1.4 6.1 1975 1 14 -4.942 130.021 16.4 6.0 1976 11 18 -4.193 135.116 3.6 6.5 1977 3 15 -4.976 131.036 75.7 6.2 1978 4 3 -4.884 133.956 6.4 6.3 1978 8 3 -0.157 131.785 40.5 6.4 1979 9 12 -1.686 135.969 18.5 7.6 1979 9 13 -1.166 136.430 17.9 6.1 1979 10 17 -1.171 136.535 18.4 6.1 1979 11 16 -1.951 134.170 37.8 6.1 1985 4 8 -4.050 136.259 18.3 6.0 1985 4 21 -5.151 130.430 91.0 6.0 1985 9 15 -4.065 136.093 4.4 6.4 1985 9 15 -4.120 136.287 11.1 6.3 1985 11 17 -1.634 134.434 26.5 6.0 1985 11 17 -1.671 134.937 11.8 7.3 1985 12 6 -1.623 134.918 19.9 6.0 1986 10 17 -5.283 131.453 58.1 6.4 1987 6 17 -5.599 130.835 67.0 7.1 1987 10 3 -5.467 131.023 74.0 6.4 1989 1 10 -3.170 130.500 32.0 6.7 1989 9 4 -4.253 136.713 9.0 6.4 1989 12 12 -4.671 130.821 74.2 6.1 1990 12 5 -5.269 131.446 75.0 6.1 1991 12 29 -4.407 132.665 42.5 6.4 1992 4 7 -4.161 130.961 51.0 6.0 1993 6 12 -4.357 135.175 10.0 6.1 1994 1 19 -3.205 136.000 23.0 6.8 1994 4 13 -3.159 136.005 29.0 6.5 1994 5 25 -4.182 135.520 15.0 6.5 1994 11 20 -2.011 135.962 16.0 6.3 1995 1 27 -4.445 134.442 22.0 6.8 1995 3 19 -4.143 135.118 26.5 6.9 1995 3 19 -4.236 135.051 19.0 6.1 1996 2 17 -0.558 135.804 19.0 6.5 1996 2 17 -0.811 136.096 32.0 6.5 1996 2 17 -0.871 136.128 32.0 6.5 1996 2 17 -0.918 136.971 36.0 8.2 1996 2 18 -0.665 136.550 20.2 6.3 1996 2 18 -1.360 136.487 11.0 6.4 1998 4 27 -2.965 136.275 24.0 6.1 1998 11 18 -3.332 130.757 31.2 6.0 1999 10 10 -2.056 134.245 10.0 6.1 2001 1 29 -0.710 133.250 14.0 6.2 2001 4 4 -5.265 132.290 17.0 6.4 2001 7 22 -5.216 132.322 38.4 6.0 2001 9 11 -0.618 133.115 31.1 6.5 2002 9 20 -1.675 134.281 24.0 6.4 2002 9 20 -1.747 134.054 9.0 6.0 2002 10 10 -1.432 133.966 15.8 6.0 2002 10 10 -1.493 134.056 48.8 6.0 2002 10 10 -1.526 133.996 36.7 6.7 2002 10 10 -1.711 134.311 16.0 7.7 From: Engdahl (2003, unpublished catalog) RELATIVE PLATE MOTIONS The relative motion of adjacent tectonic plates is depicted on the map by short vectors shown at selected locations on the plate boundary. In this presentation, one of the plates is defined as the reference plate. The vector therefore repre- sents the direction of motion of the adjacent plate relative to the reference plate. The rate of relative motion is labeled next to the vector. The components of the vector perpendicular and parallel to the plate margin approximate converg- ent/divergent and transverse direction of motion between the plates, respectively. As viewed from the reference plate, an inward directed component suggests convergence at and near the plate bound- ary that may be expressed as crustal folding, up- lift, thrust faulting, or plate subduction. Similarly, an outward directed component suggests plate divergence such as would be expected at a zone of crustal spreading. Transcurrent or transform faulting would be expected when the dominant vector component is parallel to the plate margin. In the Tectonic Setting map, the reference plate is the Australian plate and the adjacent plate is the Sunda plate. The vectors indicate that the Sunda plate is moving roughly south-southwest relative to the Australian plate at a rate that varies from about 65 mm/yr to 76 mm/yr. The Java (Sunda) Trench, deep earthquake foci, and line of volcanoes parallel to the plate boundary are characterstic of typical subduction zones. EXPLANATION Main Shock #1 5 February 2004 Main Shock #2 7 February 2004 Main Shock #3 8 February 2004 Earthquakes 1964 - 2002 0 - 69 km 70 - 299 300 - 700 Magnitude Classes 5.0 - 5.9 6.0 - 6.9 7.0 - 7.9 8.0 - 8.9 Plate Boundaries Continental Convergent Continental Rift Continental LL Transform Continental RL Transform Oceanic Convergent Oceanic Spreading Oceanic LL Transform Oceanic RL Transform Subduction Volcano PAPUA, INDONESIA 8 February 2004 08:58:51.80 UTC 3.665° S., 135.339° E. Depth 26 km Ms = 6.9 (USGS); Mw = 6.5 (USGS), 6.7 (HRV) This was the third large earthquake of the sequence that began on 5 February 2004 approximately 20 km to the northeast. The two events are notable because they had similar magnitudes and focal mechanisms. Felt (MMI VI) in Nabire. Strike N5°W Down-Dip FINITE FAULT MODEL (C. Ji, California Institute of Technology) Distribution of the amplitude and direction of slip for subfault elements (small rectangles) of the fault rupture model are determined from the inversion of teleseismic body waveforms. Arrows indicate the amplitude and direction of slip (of the hanging wall with respect to the foot wall); the slip amount is also color-coded as shown. The view is from above, per- pendicular to the fault plane. The fact that the orientation of the finite fault plane may differ from the corresponding best double couple nodal plane depicted in the focal mechanism diagram on the main map reflects differing methods of analysis and data sets. The strike of the fault rupture plane is N5°W and the dip is 80°. The dimensions of the subfault elements are 5 km in the strike direction and 4 km in the dip direction. EXPLANATION Amount of Slip 0 cm 30 60 90 120 150 180 210 240 cm 270 300 330 360 390 420 450 480 510 Finite Fault Model