Cruise Report on NT05-02 “Survey off northwest Sumatra Island” Shipboard Scientific Party Co-chiefs Wonn Soh (JAMSTEC, Japan; Leg 1 & 2) Safri Burhanuddin (AMFR, Indonesia; Leg 1) Yusuf S. Djajadihardja (BPPT, Indonesia; Leg 2) Researcher Yudi Anantasena (BPPT, Indonesia; Leg 2) Kohsaku Arai (AIST, Japan; Leg 2) Eiichiro Araki (JAMSTEC, Japan; Leg 1 & 2) Toshiya Fujiwara (JAMSTEC, Japan; Leg 1 & 2) Nugroho Dwi Hananto (LIPI, Indonesia; Leg 1) Kenji Hirata (JAMSTEC, Japan; Leg 1) Badrul Mustafa Kemal (Andalas Univ. Indonesia; Leg 1) Hananto Kurnio (BMG, Indonesia; Leg 2) Hideaki Machiyama (JAMSTEC, Japan; Leg 1 & 2) Christian Muller (BGR, Germany; Leg 1 & 2) Leonardo Seeber (LDEO, USA; Leg 2) Kiyoshi Suyehiro (JAMSTEC, Japan; Leg 2) Kazuki Watanabe (HOD, Japan; Leg 1) *Leg 1 (Feb. 14 - March 6, 2005) *Leg 2 (March 8 - 26, 2005) Important notice The information in this report is not intended to represent final interpretation of the data. The contents of this report can be modified without notification in the future. When you use the information in this report and make a presentation or publication, you are requested to cite this report in the following format. Citation to Web volume: Shipboard scientific party, Cruise Report on NT05-02 "Survey off northwest Sumatra Island", http://www.jamstec.go.jp/... [Cited YYYY-MM-DD] Individual chapters and sections can be cited in the following format with chapter and section index: (Example for Chapter 5, Section 3, Ocean Bottom Seismographic Observation) Shipboard scientific party, 5.3 Ocean Bottom Seismographic Observation. In Cruise Report on NT05-02 "Survey off northwest Sumatra Island", http://www.jamstec.go.jp/jamstec-e/sumatra/natsushima/bm/5_3_OBS.pdf(PDF:3,558KB) [Cited YYYY-MM-DD] Contents Acknowledgement(PDF:7KB) 1. Introduction 1.1 Scientific Rationale(PDF:13KB) 1.1.1 Background 1.1.2 Urgent study using R/V Natsushima 1.2 Plate Tectonics and Geological Setting 1.2.1 Tectonic history 1.2.2 Onland geology 1.2.3 Offshore 1.3 Short Review: Preliminary results and observations of the December 2004 Great Sumatra Earthquake(PDF:276KB) 1.3.1 Hypocentral parameters 1.3.2 Aftershock area and rupture zone 1.3.3 Other basic seismic information 1.3.4 Seismic body wave analyses 1.3.5 Normal-mode study 1.3.6 Observation of crustal deformation and GPS study 1.3.7 Tsunami 1.3.8 Summary 2. Cruise Narrative 2.1 Ship log in Leg 1 2.2 Ship log in Leg 2 3. List of Participants(PDF:2,352KB) 3.1 Leg 1 3.2 Leg.2 4. Scientific Equipment 4.1 Multi-Beam Bathymetry & Sidescan Image(PDF:72KB) 4.2 Single Channel Seismic Equipment and Survey Specification(PDF:34KB) 4.3 Ocean Bottom Seismometers(PDF:464KB) 4.4 R/V Natsushima and ROV Hyper-Dolphin(PDF:1,140KB) 4.4.1 Information about R/V Natsushima 4.4.2 Research equipment 4.4.3 ROV Hyper-Dolphin 4.4.4 SAHF (heat flow measurement) 4.4.5 Gamma ray sensor 4.4.6 CTD-DO measurement 4.5 Subbottom Profiler (SBP) and Sidescan Sonar (SSS)(PDF:396KB) 5. Preliminary Results 5.1 Multi-Beam Bathymetry & Sidescan Images(PDF:12,046KB) 5.1.1 Data collection 5.1.2 Accretionary wedge and outer-arc-high 5.1.3 Aceh Fore-arc Basin 5.2 Single Channel Seismic Reflection Measurements(PDF:9,103KB) 5.2.1 Location map 5.2.2 SCS onboard processing 5.2.3 Description and preliminary interpretation of single-channel seismic profiles 5.3 Ocean Bottom Seismographic Observation(PDF:3,558KB) 5.3.1 Seismological background of the study area 5.3.2 Seismicity before 26 December 2004 earthquake 5.3.3 Seismicity after 26 December 2004 earthquake 5.3.4 Section description 5.3.5. Objective of OBS observation and the network geometry 5.3.6 Onland seismographic station in Sumatra Island 5.3.7 Deployment 5.3.8 Airgun shot for OBS 5.3.9 OBS recovery 5.3.10 Preliminary analysis: determination of hypocenters from OBS data 5.4 ROV Seabottom Observations 5.4.1 Leg 1 5.4.2 Leg 2 5.5 Subbottom Profiler (SBP) and Sidescan Sonar (SSS)(PDF:5,374KB) 6. Final remarks(PDF:15KB)