Cruise Report NT14-02

Transcription

1 Cruise Report NT14-02 Sagami Bay, Iheya North knoll field, South-West Japan Proposal title Sea Trail of performance of observation AUV "JINBEI" Proposal title Verification of the hydrothermal circulation mode using DC resistivity and Electro-magnetic method R/V Natsushima 14 Feb Feb 2014

2 Contents 1. Cruise information and summary of NT14-02 cruise 2. List of Participants 3. Ship Logs Instruments 4.1. AUV JINBEI 4.2 OBEM 5. Operation report and preliminary results 5.1 AUV JINBEI 5.2 OBEM recovery 5.3 Bathymetric survey Appendix R/V Natsushima

3 Cruise summary of NT14-02 cruise Cruise information Cruise number NT14-02 Name of the cruise R/V Natsushima Chief scientist Tadahiro Hyakudome (MARITEC, JAMSTEC) Representative of the Science Party 1 Tadahiro Hyakudome (MARITEC, JAMSTEC) Title of the cruise Sea Trial of Maneuverability and Survey Ability of AUV "JINBEI" Representative of the Science Party 2 Takafumi Kasaya (SRRP, JAMSTEC) Title of the cruise Verification of the hydrothermal circulation mode using DC resistivity and Electro-magnetic method Cruise period 14 Feb Feb 2014 Ports of call Yokosuka (Sumitomo Heavy Industry) Yokosuka (Sumitomo Heavy Industry) Research Area Sagami bay and Iheya (Fig.1) Fig.1 Ship tracks of this cruise.

4 Cruise proposal 1 Sea Trial of Maneuverability and Survey Ability of AUV "JINBEI" We took place performance tests for the AUV "JINBEI" such as maneuverability test, survey ability and acoustic telemetry. And we confirmed every functions of the AUV after improvement and maintenance. But, we understood that we cannot recover the AUV with safety using equipment of the NATSUSHIMA at the launch and recover training. So we cancel the sea trail of the vehicle. Cruise proposal 2 Verification of the hydrothermal circulation model using DC resistivity and Electro-magnetic method It is very important for the study of the origin and formation of hydrothermal deposit to detect the subsurface hydrothermal circulation system. In Iheya North knoll field, seismic survey and deep-sea drilling study had carried out. However, their result have not been fully elucidated the whole hydrothermal circulation system. Geophysical exploration method based on the electromagnetism is very sensitive to the conductive fluid and mineral resources. Therefore, we have carried out the DC resistivity survey and magneto-telluric (MT) survey around Iheya North knoll filed. In this cruise, we tried to recover six ocean bottom electro-magnetometers (OBEMs) for the MT survey, and were succeeded the recovery operation perfectly. We will obtain the resistivity structure of this area to analyze OBEM s data.

5 2. List of Participants NT14-02 list of participants (2014/02/ /02/17) Scientists HYAKUDOME TADAHIRO MATSUURA MASAMI YOSHIUME TSUYOSHI OCHI HIROSHI NAMBU YOSHINOBU KOMUKU TETSUYA WATANABE YOSHITAKA NAKATANI TAKESHI OOWATARI YUKI NIIKURA JUNYA KIDA YUKIHIRO KITADA KAZUYA KANAYAMA KAZUHIRO ABE MASAYOSHI Marine technician IWAMOTO HISANORI R/V NATSUSHIMA Crew Captain Chief Officer 2nd Officer 3rd Officer Chief Engineer 1st Engineer 2nd Engineer Jr.2nd Engineer 3rd Engineer Chief Electronics Operator 2nd Electronics Operator Boat Swain MASUJIMA HIROAKI KATO HIROYUKI KATSUMATA MOTOI FUJII SYUNSUKE KANEDA KAZUHIKO TADOOKA NAOHITO MURAKAMI MORIHIKO GIBU DAISUKE YAMAGUCHI KATSUTO NASU TOKINORI KURAMOTO YOSHIKAZU HOSOKAWA SEIJI

6 Able Seaman CHIMOTO TSUYOSHI Able Seaman ISOBE HIDEO Able Seaman MIYASHITA TAKUYA Sailor UZUKI SHINSUKE Sailor NAKANISHI TORU Sailor MOTOOKA YUTA No.1 Oiler IKEDA TOSHIKAZU Oiler YOSHIDA KATSUYUKI Oiler UEDA MASANORI Oiler TANAKA MASAKI Oiler SATO DAIKI Oiler SHIMOHATA SHOTA Chief Steward MATSUMOTO ISAO Steward FUKUMURA HIDEO Steward ONOUE TASUNARI Steward HIRAYAMA KAZUHIRO Steward KUBOTA RYU

7 NT14-02 list of participants (2014/02/ /02/25) Scientists KASAYA TAKAFUMI KITADA KAZUYA NITTA SUEHIRO KIYOSAWA MASAHARU Marine technician IWAMOTO HISANORI R/V NATSUSHIMA Crew Captain Chief Officer 2nd Officer 3rd Officer Chief Engineer 1st Engineer 2nd Engineer Jr.2nd Engineer 3rd Engineer Chief Electronics Operator 2nd Electronics Operator 3rd Electronics Operator Boat Swain Able Seaman Able Seaman Able Seaman Sailor Sailor Sailor No.1 Oiler Oiler Oiler Oiler Oiler MASUJIMA HIROAKI KATO HIROYUKI KATSUMATA MOTOI FUJII SYUNSUKE KANEDA KAZUHIKO TADOOKA NAOHITO MURAKAMI MORIHIKO GIBU DAISUKE YAMAGUCHI KATSUTO NASU TOKINORI ISHIWATA HIROKI KURAMOTO YOSHIKAZU HOSOKAWA SEIJI CHIMOTO TSUYOSHI ISOBE HIDEO MIYASHITA TAKUYA UZUKI SHINSUKE NAKANISHI TORU MOTOOKA YUTA IKEDA TOSHIKAZU YOSHIDA KATSUYUKI UEDA MASANORI TANAKA MASAKI SATO DAIKI

8 Oiler Chief Steward Steward Steward Steward Steward SHIMOHATA SHOTA MATSUMOTO ISAO FUKUMURA HIDEO ONOUE TASUNARI HIRAYAMA KAZUHIRO KUBOTA RYU

9 3. Ship Logs Date Local Time Description Position/Weather/Wind/Sea condition 14-Feb-14 08:00 scientists onboard 2/14 12:00 (UTC+9h) 09:00 departure from Sumitomo heavy indus., Yokosuka N, E 10:00-10:20 lecture for life of shipboard life and safety snow 10:20-11:30 meeting for JINBEI launch and recovery process North-7 (near gale) drift at westward off Miura pen. 5 (sea rough) 4 (Moderate average) Visibly: 1' 15-Feb-14 11:00 left off westward off Miura pen. for Yokosuka No.4 2/15 12:00 (UTC+9h) 13:45 let go anchor at Yokosuka No N, E 15:00-17:00 JINBEI launch and recovery test cloudy North-5 (fresh breeze) 3 (sea slight) 3 (Moderate short) Visibly: 8' 16-Feb-14 12:15 heaving anchor, for Sagami bay 2/16 12:00 (UTC+9h) 16:00-17:30 JINBEI launch and recovery test N, E fine but cloudy NNW-7 (near gale) 4 (sea moderate) 2 (Low swell long) Visibly: 8' 17-Feb-14 04:00 left off Sagami bay for Yokosuka No.4 2/17 12:00 (UTC+9h) 07:00 let go anchor at Yokosuka No N, E 14:00-16:00 got to the shore Sumitomo heavy indus. fine but cloudy 12 scientists disembarked, 3 scientists embarked ESE-2 (light breeze) 1 (calm) 1 (Low swell sea) Visibly: 8'

10 18-Feb-14 transit to research area 2/18 12:00 (UTC+9h) N, E cloudy NW-7 (near gale) 5 (sea rough) 4 (Moderate average) Visibly: 8' 19-Feb-14 transit to research area 2/19 12:00 (UTC+9h) 13:00-13:45 onboard seminar N, E cloudy NNW-7 (near gale) 5 (sea rough) 5 (Moderate long) Visibly: 7' 20-Feb-14 transit to research area 2/20 12:00 (UTC+9h) N, E cloudy North-6 (strong breeze) 4 (sea moderate) 4 (Moderate average) Visibly: 8' 21-Feb-14 04:00 arrived at research area 2/21 12:00 (UTC+9h) 08:02 released XBT N, E 12:58 send release command to OBEM B1 fine but cloudy 13:58 OBEM B1 on deck NNE-4 (moderate breeze) 14:45 send release command to OBEM B3 3 (sea slight) 15:59 OBEM B3 on deck 4 (Moderate average) 16:31 send release command to OBEM B4 Visibly: 8' 17:41 OBEM B4 on deck 19:20 MBES and plume survey 22-Feb-14-05:12 MBES and plume survey 2/22 12:00 (UTC+9h)

11 06:48 send release command to OBEM B N, E 07:51 OBEM B2 on deck fine but cloudy 08:25 send release command to OBEM B5 North-4 (moderate breeze) 09:22 OBEM B5 on deck 3 (sea slight) 09:46 send release command to OBEM B6 3 (Moderate short) 10:39 OBEM B6 on deck Visibly: 8' 11:19-20:09 MBES and plume survey 22:11 MBES 23-Feb-14-09:48 MBES 2/23 12:00 (UTC+9h) 10:31 released XBT N, E 11:01 MBES and plume survey fine but cloudy NE-3 (gentle breeze) 2 (sea smooth) 2 (Low swell long) Visibly: 8' 24-Feb-14-18:07 MBES and plume survey 2/24 12:00 (UTC+9h) N, E fine but cloudy East-4 (moderate breeze) 3 (sea slight) 2 (Low swell long) Visibly: 8' 25-Feb-14 08:30 disembarked by boat at Naze port, AMAMI OOSHIMA 2/25 08:30 (UTC+9h) AMAMI OOSHIMA

12 4. Instruments 4.1. AUV JINBEI Fig.2 AUV JINBEI Specifications of the Fuel Cell System Type : AUV Size : 4 x 1.1 x 1.0 m Weight : 1,700 kg Maximum Depth : 3,000m Cruising Speed : knots Min Cruising Alt. : 30 m Min Turning Radius : 20 m Endurance : 10 hours (@ 2 knots) Communication : Acoustic, Optical, Satellite & Wireless LAN Navigation System : INS, DVL, Depth censor, Altimeter & SSBL

13 4.2 Ocean bottom electro-magnetometer (OBEM) The OBEM system can measure time variations of three components of magnetic field, two components of horizontal electric field, the instrumental tilts, and temperature. It mainly consists of one 17-inch glass sphere, sensor unit in aluminium/titanium pressure housing and electrode arm unit with arm holding mechanism (Fig ). The glass sphere involves data logger and a lithium battery pack. The sensor unit has a high-accuracy fluxgate magnetometer, tiltmeter and thermometer. The electrodes are Ag-AgCl equilibrium type made by Clover Tech. For electric field, four voltage differences between the electrodes on the tip of the pipes and the ground electrode are measured. The electrodes were monitored their self-potentials in laboratory in advance of the seafloor observation and pairs that the coherence is high enough were selected, in order to reduce the noise due to the voltage drift of electrodes themselves. A transponder unit, radio beacon and a flashlight are also mounted on the OBEM. The acoustic system can communicate with the SSBL system and it is easy for us to detect its position in the sea or on the seafloor. There are a transponder unit mounted on the OBEM system. This transponder unit, of which the acoustic and the pressure case units are combined, has a 2-year battery life. Fig OBEM system Concepts of the type the OBEM system are miniaturization, a high sampling rate, easy assembly and recovery operations, and low costs of construction and operation. The arm holding mechanism, which electrode arm is folded when OBEM is in surfacing (Fig ), enable recovery operation even by the small ship that do not equip A frame (Kasaya et al., 2006; Kasaya and Goto, 2009).

14 Fig Electrode arm-holding mechanism of type A OBEM References Kasaya, T., T. Goto, and R. Takagi, Marine electromagnetic observation technique and its development For crustal structure survey-, BUTSURI-TANSA, 59, (in Japanese with English abstract), Kasaya, T., and T. Goto, A small OBEM and OBE system with an arm folding mechanism, Exploration Geophysics, 40, 41-48, 2009.

15 5. Operation report and preliminary results 5.1 JINBEI experiment Test Point: Port at Sumitomo Heavy Industries Ship refuge cause of bad sea condition - Training of scenario simulator 2014 February 15 Test Point: Yokosuka 4 ward - Training for new Launch and Recovery System - Functional tests for the vehicle 2014 February 16 Test Point: Near Hatsushima Island - Training for new Launch and Recovery System 2014 February 17 Port at Sumitomo Heavy Industries - Replace researcher Figure recovery scene

16 5.2 OBEM recovery operation We carried out a recovery operation of six OBEMs (Fig ) deployed in MR13-E02 cruise at 21 and 22 Feb We send an acoustic release signal from R/V Natsushima, and all OBEMs were recovered perfectly. The estimated accent rate was approximately 43 m/min base on the SSBL system. Figure shows the recovery operation of an OBEM on deck. After the recovery operation, the clock of OBEM was compared with the GPS clock. We also downloaded all data from six OBEMs completely. Figure Photo of the recovery operation. Figure Site map of deployed OBEMs.

17 Table Information of the OBEMs. Site OBEM Deployed Deployed Deployed Landed Landed Depth ID ID time (JST) Latitude Longitude time (JST) Landed Latitude Longitude (m) 2013/11/ /11/30 B1 JM109 14: N E 14: N E /11/ /11/30 B2 JM100 16: N E 16: N E /11/ /11/30 B3 JM103 12: N E 12: N E /11/ /11/30 B4 JM105 10: N E 10: N E /11/ /11/30 B5 JM108 17: N E 18: N E /12/5 2013/12/5 B6 JM110 15: N E 16: N E Table Information of the OBEMs. site ID OBEM ID Landed Latitude Landed Longitude Depth Send release command time (JST) On deck time (JST) B1 JM N E /2/21 12: /2/21 13:53 B2 JM N E /2/22 06: /2/22 07:51 B3 JM N E /2/21 14: /2/21 15:59 B4 JM N E /2/21 16: /2/21 17:41 B5 JM N E /2/22 08: /2/22 09:22 B6 JM N E /2/22 09: /2/22 10:39

18 5.3. MBES survey We have conducted a bathymetric survey to reveal the detailed morphological features in the mid Okinawa Trough. Bathymetry data was collected by the multi-beam echo sounder (MBES) using the SeaBat 8160 system equipped on board R/V Natsushima. The obtained data were calibrated based on the sound speed profile in the water column based on expendable bathythermograph (XBT). The ship speed was 3-6 knot and the track spacing was 0.3 to 0.8 nautical mile to maintain the data quality. The resulting bathymetric map is illustrated in Fig and the survey lines are listed in Table Figure Multinarrow beam bathymetric map of the mid Okinawa Trough. The black lines are survey lines during the cruise.

19 Table List of MBES survey lines

20 Appendix R/V Natsushima Ocean research vessel Natsushima was built as a support vessel of submersible SHINKAI 2000 in 1980s. R/V Natsushima was reconstructed as a support vessel of Hyper Dolphin. General information about NATSUSHIMA Length:67.4m Bow thruster: 4T/1.4T 220kw/110kw 1 1 Width:13.0m Maximum speed:12.0kt Depth:6.3m Duration:5000 mile Max capacity: 55 persons (18 scientists) Gross Tonnage:1739t Main prop: Variable pitch propeller 2 axis 4 Wing CPP,540N Research equipment (1) MBES Bathymetric data were collected by the SEABAT 8160 (RESON). The SEABAT is a multibeam survey system that generates data for and produces wide-swath contour maps and side scan images. It transmits a sonar signal from projectors mounted along the keel of the ship. The sonar signal travels through the sea water to the seafloor and is reflected off the bottom. Hydrophones mounted across the bottom of the ship receive the reflected sonar signals. The system electronics process the signals, and based on the travel time of the received signals as well as signal intensity, calculate the bottom depth and other characteristics such as S/N ratio for echoes received across the swath. Positioning of depths on the seafloor is based on GPS and ship motion input. The data is logged to the hard disk for post processing which allows for additional analysis. Plotters and side scan graphic recorder are also included with system for data recording and display. Max depth: 3000 m Frequency: 50 khz Number of beams: 126 Swath angle: 150 degree (depend on depth) Each beam width: 1.5 x 1.5, 3.0, 4.5, or 6.0 degree Minimum resolution: 1.4, 2.9, 8.9 cm (depend on above beam width) Maximum transmit rate:15 ping/sec (2) PDR

21 This can record a water depth at right below and make contour map together with navigation data. Max depth: more than 3000m Record Range: 200~800m (changeable) Frequency: 12kHz +/-5% Output: more than110db (0dB unbar at 1m) Directivity: conical beam pattern Beam width: 15deg. +/-5 deg. (-3dB) Pulse width: 1, 3, 10, 30msec (3) XBT equipment XBT profile a vertical water temperature by free-fall probe. Maximum measurable depth:1830m Measure range:-2 deg.~+35 deg. (4) Navigation equipment Position of the ship is measured by DGPS within about 3m error. ROV and transponder are measured by acoustic positioning system. (5) Laboratory There are laboratories at the back part of second deck. Each room has AC100V power supply and LAN network. The video of HPD diving and deck-camera video are distributed to the laboratories and every cabin. Second laboratory: There are two desktop PCs (windows and Mac), equipment for video editing, color copy with printer, meeting desk and white board. Hi-definition video of HPD is distributed to this laboratory. You can copy from a digital data to HDD and DVD-R. Third laboratory: There are two sinks, refrigerator (-80deg. low temperature refrigerator, Incubator, domestic refrigerator, ice maker, ice crasher) and filtrate water system (Milliq Integral). And sea water for experiment is supply to the sink. Dry laboratory: There are a work desk and a shelf for baggage. This room has 4 beds to be used as a private one in case that there are many researchers. At the work deck, there are rock-cutter rooms Rock-cutter room: There are a rock cutter and two grinders. And exclusive

22 video player is set to describe rocks with playing video of ROV diving.