Ambae volcano - Latest News
Transcription
Ambae volcano - Latest News
EXPLORING THE GEONET PROJECT The eruption of Ambae volcano Volcano monitoring capability utilised Monitoring tectonic movement Well connected: Deep Drilled Braced Monuments GeoNet team on the move GNS Science finds its Avalon home I S S U E S I X – J U LY 2 0 0 6 I N SI D E I S S U E S I X – J U LY 2 0 0 6 MONITORING TECTONIC MOVEMENT Well connected: deep drilled braced monuments. PAGE 3 THE ERUPTION OF AMBAE VOLCANO GeoNet’s volcano monitoring capability utilised. PAGE 4 UP CLOSE Vital people in the GeoNet project. PAGE 6 ON THE MOVE GNS Science moves to Avalon. PAGE 8 COVER IMAGE The completed Deep Drilled Braced Monument at Rangitukua, by the shores of Lake Taupo. www.geonet.org.nz GeoNet is a non-profit project operated by the Institute of Geological & Nuclear Sciences Limited (GNS Science) with core funding from the Earthquake Commission. It involves GNS Science building and operating a modern geological hazards monitoring system for New Zealand. GeoNet is a 10 year project which started in 2001. It will provide real-time monitoring and data collection for rapid response to and research into earthquakes, volcanic eruptions and landslides. Data collected by GeoNet are available free of charge. Visit www.geonet.org.nz for more information. 2 – GeoNet G EONET: EDITORIAL EXPANSION AND DELIVERY It has been a year of transition for the GeoNet project. The scope of the project has grown, major staff changes have taken place, and the Wellington-based staff have made the move to new accommodation at Avalon. KEN GLEDHILL EMAIL: [email protected] In October last year the founding Project Director, Hugh Cowan, left GNS Science to take up the position of Research Manager at EQC. Hugh has made a huge contribution to geological hazards research and monitoring in New Zealand over an extended period of time, a contribution that continues in his new role. Hugh was the driving force behind the establishment of GeoNet, and ably led the project for the formative first four years. This included the first triennial review and the achievement of ensuring that GeoNet will proceed as originally intended: a ‘fit-for-purpose’ geological hazards monitoring system for New Zealand. The enactment of the recommendations of the triennial review of late 2004 saw the investment in GeoNet by EQC increase from $5 million to $8 million per annum. This is allowing the installation of a better distribution of sensing sites, improved access to the data for researchers, and more emphasis on transforming the raw data into useful information for emergency managers. GeoNet project expansion resulted in staff recruitment being a major focus during the last year. After early problems finding suitable new staff, a highly proactive approach was adopted, including visits to tertiary institutions. This was very successful as witnessed by the new faces presented on pages 6 and 7. These people bring to the GeoNet project a variety of skills and talents, as well as youthful enthusiasm. The tragic tsunami of 24 December 2004 brought about an increased focus on our international obligations. This has involved working actively with our Australian counterparts to enhance tsunami monitoring systems in the Pacific, and a greater involvement with the Pacific Tsunami Warning System, including the recent Pacific-wide tsunami exercise. We are now exchanging data with various international institutions, and GeoNet will be the focus for the New Zealand tsunami warning efforts. Our commitment to the nations of the Pacific was demonstrated by the involvement in the NZAid response to the volcanic eruption of Ambae volcano in Vanuatu, reported on pages 4 and 5. It has also been a year of consolidation as we have assimilated the new staff and expanded the project to enable us to deliver on the promise of the GeoNet concept. Much of this work has gone on in the background without obvious changes to the public face of the project in the form of the GeoNet website. However, the foundations have been laid for big changes, which will be progressively rolled out over the coming year. These will include enhanced information for the general public and emergency managers, and better access to the data for researchers. To improve the usefulness of the information we provide we will be consulting many of you about your requirements. Ken Gledhill, GeoNet Project Director, GNS Science MONITORING TECTONIC MOVEMENT WELL CONNECTED: DEEP DRILLED BRACED MONUMENTS Continuous Global Positioning System (CGPS) equipment is being used to monitor the crustal deformation occurring in the zone between the Pacific and Australian plates along the east coast of the North Island, an area known as the Hikurangi Margin. Some 60 monitoring stations are being installed between Hicks Bay, Wellington and Wanganui. Above: The uninstrumented quadropod, and the finished CGPS installation, at Castlepoint on the Wairarapa coast. Below: Drilling deep on Mt Climie in the Rimutaka Range. To get data that are reliable over a very long time period and to capitalise on the accuracy of the CGPS system (a few millimetres), the monument on which the antenna is mounted must have a very rigid and stable connection to the underlying land mass. Over the last few years most of our monuments have been concrete pillars with reinforcing bars glued about 2m deep into rock. This design required good rock at the surface, but at times it was hard to be sure this rock was well connected with the greater land mass. In some areas good rock is hard to find, such as in central Hawke’s Bay where there is a lot of limestone, and the volcanic region where the land is covered by layers of ash. To overcome these limitations we have begun using a monument design developed in the United States known as the Deep Drilled Braced Monument or DDBM. A DDBM has the form of a quadropod with the addition of a central vertical leg. It is about 1.6m high. The legs are made of thick-walled stainless steel pipe. Each leg penetrates about 10m into the ground and the bottom 6m are grouted in place. The 4m just below the surface are in a foam rubber casing to isolate the leg from potentially unstable near-surface material. This means the monument foundation is far more likely to be in bedrock that is stable with respect to the surrounding geology. We first did a trial installation on Mt Climie, with Webster Drilling and Exploration Ltd doing the complete construction. This was very successful and only a few changes to design and technique were needed. The drilling was done with a purpose-built pneumatic drilling rig, which is light enough to be transported to a site by helicopter. Webster’s have since installed another 15 DDBMs, some around Lake Taupo and Rotorua. Some peculiarities of the concrete pillar design meant it was not easy to contract out their construction, so we built them ourselves. Using Webster’s to build the DDBM design, has proven to be a significant advantage as it leaves our staff to concentrate on the more specialised aspects of installing stations. This has added extra impetus to our build programme. Contact: Colin Dyer Email: [email protected] GeoNet – 3 WORLD STAGE THE ERUPTION OF AMBAE VOLCANO On 26 November 2005, Ambae volcano in Vanuatu began to erupt and the Vanuatu Volcano Alert Level was quickly raised to Level 2 (representing minor eruptive activity). As a precaution, about 4000 people were moved away from the immediate area and local volcanologists were dispatched to the island to assess the eruption. They soon felt they needed additional assistance and the New Zealand Government, donor agencies and other aid contributors were asked to assist. The Ministry of Foreign Affairs and Trade, through NZAID, contracted two volcanologists from GNS Science to mount a response visit. Their objectives included assisting the local geological and emergency response organisations to interpret the eruption, giving a detailed assessment of the current level of eruptive activity, and offering some prognosis of the future activity at the volcano. They were also asked to establish a temporary seismic monitoring system on Ambae to collect data to help with the assessment of activity, and to provide a means by which Vanuatu scientists can continue to monitor the activity for the foreseeable future. Six days were spent on the volcano, establishing the seismic equipment, gathering and analysing data, observing the eruptions, and reporting the status of the volcanic activity to the Vanuatu Government. Additional data and support came from French scientists based in Noumea, and staff and students from Massey University, Palmerston North. On arrival, small scale eruptions were occurring in one of the summit crater lakes (Lake Vui) and had started to build a cone. Over the next few days this grew to over 70 metres high and 200 metres across, and eventually a crater lake was to become established in the crater of this new cone. Brad Scott and Steve Sherburn departed for Vanuatu, taking three seismic recording systems and other volcano monitoring tools with them. This was a challenging assignment due to the short lead-time, the remoteness of the location, and a lack of volcanological data. This was offset by their experience of monitoring and assessing eruptions, particularly past work in similar situations in Papua New Guinea, Tonga and Vanuatu. After analysing visual observations, seismic data, gas data from the French team, and a review of the volcano’s historic activity, scientists began to assess the eruption as small scale and of no major threat to the local population. This information was passed to the Disaster Co-ordination Group at Port Vila, the local government and the community in the form of bulletins, which were also translated into the local language Bislama. The assessment concluded that the Vanuatu Volcano Alert Level 2 should remain until activity declined. The assignment underscores the value of permanent monitoring of active volcanoes, which establishes each volcano’s unique characteristics over a period of time. This provides a basis for correlating observed activity with any changes in a volcano’s geophysical measurements, leading to a clearer understanding of its behaviour. Contact: Brad Scott Email: [email protected] 4 – GeoNet Top: Aerial views of Lake Vui, showing the cone which grew in the lake during the November-December 2005 eruptions (left to right: 8 December 2005, 8 December 2005, 16 March 2006). Background photograph: Aerial view of an explosion through the active crater of the new cone, 8 December 2006. Inset, left: Seismologist Steve Sherburn (squatting left of instrument) and local volcanologist Charlie Douglas (kneeling right of instrument) explaining to the villagers how the portable seismograph works. GeoNet – 5 VITAL PEOPLE IN THE GEONET PROJECT JEREMY COLE-BAKER Operations Technician, GNS Science BRYAN FIELD Data Control Analyst, GNS Science Jeremy Cole-Baker works in our Wairakei office assisting with sample collection programmes, as well as the installation and maintenance of a variety of equipment. Bryan Field is the new Data Control Analyst for GeoNet. His responsibilities include data quality and completeness, data archiving and database management. He is also being trained in seismology. He completed an MSc in Earth Sciences at Waikato University, and also brings with him a knowledge of Computer Science and Information Technology. Jeremy enjoys the variety of work in the GeoNet project, both the environment and the equipment: “This is a wonderful part of the country to be working in”. He adds, “I also like being part of a project which is providing both scientific data and benefits to hazard management, and working with a great team of people”. ANNIE DOUGLAS GPS Operations Scientist, GNS Science Annie Douglas is working with GeoNet selecting sites for our rapidly expanding continuous GPS network. TOP TO BOTTOM: JEREMY COLE-BAKER ANNIE DOUGLAS BRYAN FIELD RICHARD GUEST She completed a BSc (Hons) in Geology from the University of Otago, which allowed her to travel to such interesting places as Germany and the Hawaiian Volcano Observatory. She then returned to New Zealand to complete an MSc in Geophysics. Annie’s research project “A Geodetic Investigation of Slow Slip in the Hikurangi Subduction Zone beneath Raukumara Peninsula” allowed her to work in collaboration with GNS Scientists. Annie says, “I am excited by my new role here at GeoNet and feel that it offers me a great opportunity to make a positive contribution to Earth Science in New Zealand”. 6 – GeoNet Bryan completed an MSc in Physics at the University of Otago; his thesis “Development of a Laser Frequency Control System” developed his research and analytical skills, which led on to a career in science. Bryan worked as an Aerodynamics and Surface Friction Scientist at Opus Central Laboratories before joining GNS Science. RICHARD GUEST Software Engineer, GNS Science Richard Guest assists with all Information Technology and Systems Development projects within GeoNet, with specific reference to integrating hardware into the geophysical networks. He completed a BIT (Hons) in Computer Systems Engineering at Victoria University, his specialties including working with Java, networking and embedded technologies. Richard has previously worked with the SIMS team at ESR (Environmental Science and Research) and as an electronics technician at 4RF Communications. RUSSELL MICHELL Web Developer, GNS Science BAISHAN PENG Analyst Programmer, GNS Science Russell Michell is working with the GeoNet team researching and developing the GeoNet website and its design, usability, maintainability and functionality. Baishan Peng works with GeoNet developing web applications to view and manage geological hazards information. He originates from Cambridge, England where he completed a BSc in Cognitive Science from the University of Hertfordshire in Hatfield. After coming to New Zealand in 1999, Russell worked at a web design company before heading back to the United Kingdom where he worked as webmaster at Anglia Polytechnic University in Cambridge, and then as in-house web developer for Daryl Willcox Publishing, before coming back to New Zealand and joining GNS Science in 2006. Whilst developing the GeoNet website, Russell hopes to learn yet more about what makes a great website, from the user experience right down to the server environment. NORA PATTERSON Seismology Operations Scientist, GNS Science Nora Patterson has been working with GeoNet selecting sites for the expanded seismograph networks and learning about data communications, seismometers and earthquake seismology. Arriving in Wellington in 1999 from the USA, via Australia, Nora completed a BSc in Geology and Mathematics, BSc (Hons) in Geophysics and an MSc in Geology at Victoria University. This led to contract work on the Taupo caldera, acquiring an ice core from Antarctica and GPS-based modelling near the Lambert Glacier in the Antarctic. She has also worked as a GIS technician for Terralink. After completing a BSc in Geology in his home country of southern China, Baishan worked as a consulting geologist in mining and civil engineering. Baishan and his family then emigrated to New Zealand in 1997, where he received an MSc in Engineering Geology from the University of Canterbury and a postgraduate Diploma in Computing from Lincoln University. Baishan first worked for GNS Science as a GIS technician working on GIS database development and support for geological hazards. After working as a Java developer for MakeTXT.com in Christchurch, Baishan returned to GNS Science in 2006 as a developer for GeoNet. SAM TYLER Field Operations Technician, GNS Science As a Field Operations Technician, Sam’s job involves a multitude of tasks including installing, commissioning and maintaining geophysical equipment and data communications, as well as travelling around the country to investigate and understand new technologies. TOP TO BOTTOM: RUSSELL MICHELL NORA PATTERSON BAISHAN PENG SAM TYLER Sam completed a BScTech (Hons) in Electronics and Instrumentation at Victoria University and, after a four-year career as a lifeguard at Karori Pool, was the number one facility in-charge guard before taking up his position with GNS Science in October 2005. Nora says, “I’m looking forward to the learning and challenges that will be part of my job as Seismology Operations Scientist”. GeoNet – 7 GEONET TEAM ON THE MOVE During early January 2006, the GeoNet Project team was relocated to the new GNS Science premises at Avalon in Lower Hutt. GNS Science’s natural resources and natural hazards groups, along with support and corporate staff, have moved into the Avalon building, which was formerly the home of the New Zealand National Film Unit. Although largely working out of the Avalon site, some electronic equipment has yet to be installed at Avalon and operations technicians continue to travel between the two sites. The satellite dish, radio equipment and the hardware for field instruments are still located at Gracefield; within several months most of this equipment will be in place at Avalon. MANAGEMENT CONFERENCE PLANNING FOR A VOLCANIC CRISIS Above: GeoNet screens at GNS Science, monitoring seismic activity in real time. Another improvement at the new Avalon site was the installation of two large display screens which show seismograph drums, recent earthquake information, felt report maps and other information from the GeoNet website. These screens provide an ideal display for visitors to the project and staff alike. A museum project has been established by GNS Science to preserve, catalogue, and display historic geophysical instruments. Selected equipment was rescued from warehouse obscurity, where it was in danger of being lost, and moved to safe storage on the Avalon site. Some of these items will be restored and put on display. CONTACT DETAILS GeoNet website: www.geonet.org.nz Email: [email protected] Address: GNS Science, PO Box 30-368, Lower Hutt, New Zealand Editor: Jan Harris GeoNet News is published twice yearly. Additional copies are available, at no cost for domestic delivery, from Leanne Dixon, GeoNet Administration Coordinator Email: [email protected] Phone: +64 4 570 4888 Articles published in this newsletter may be quoted or reproduced as long as GNS Science is acknowledged as the source. GNS Science retains copyright on photographs, diagrams and illustrations and reproduction may only occur with prior written approval. Main funding agency: ISSN 1176-0567 8 – GeoNet 7TH NATURAL HAZARDS When: 8-10 November 2006 Where: Auckland Contact: David Johnston Email: [email protected] The collection includes a variety of equipment going all the way back to a Milne seismograph (circa 1900). Other examples include a Barraud chronometer, two Askania magnetometers, gravimeters, pendulum clocks, a number of seismometers, and a full range of strong motion instruments. Above: The GeoNet team outside Hutton Building, Gracefield, on the departure of founding Project Director, Hugh Cowan (far right), October 2005. Photo by Colin McDiarmid, 2005. COMING UP... When: 22-25 August 2006 Where: Christchurch Contact: Daryl Barton Email: [email protected] The move allows for more interaction among staff, eliminating the isolation that went with the numerous separate buildings at the Gracefield site. The new premises allow easy (and dry!) access to facilities such as the library, cafeteria and the excellent theatre. The move was accomplished with minimal disruption and the team was working normally within one or two days. A previous move within the Gracefield campus, when the GeoNet Project was first established, had given staff recent experience in moving and reduced any major build-up of office clutter. Lead organisation in the GeoNet project