GEONET NEWS EXPLORING THE GEONET PROJECT ISSUE THREE AUGUST 2003

Transcription

1 GEONET NEWS EXPLORING THE GEONET PROJECT ISSUE THREE AUGUST 2003

2 IN SIDE ISSUE THREE JULY 2003 VOLCANOES EXHALING CO 2 provides an early warning PAGE 4 FRIENDS OF THE NETWORK Meridian Energy linked to GeoNet PAGE 5 TAIWAN: SETTING THE PACE FOR HAZARD RESPONSE Cutting-edge hazard research PAGE 6 GEONET TO EXPAND SATELLITE LINKS The long way home PAGE 8 COVER IMAGE This antenna farm at the Optus Broadcast Operating Centre in Sydney, Australia, will link instruments in remote parts of New Zealand to the GeoNet data centres in Lower Hutt and Wairakei. GeoNet is a non-profit project operated by the Institute of Geological & Nuclear Sciences Limited (GNS) with core funding from the Earthquake Commission and the Foundation for Research Science & Technology. It involves GNS building and operating a modern geological hazards monitoring system for New Zealand. GeoNet is a 10 year project which started in 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 for more information. GEONET: EDITORIAL A PRODUCTIVE SECOND YEAR The end of June 2003 sees the conclusion of a productive second project year for GeoNet. The project team would like to thank our service providers, contractors and many stakeholders in the HUGH COWAN community for helping to keep GeoNet on track [email protected] and within budget. The year s milestones include improvements in monitoring for two regions that pose special hazards, the completion of a modern survey control network in the North Island for Land Information New Zealand (LINZ), and the introduction of new equipment and techniques for monitoring volcanoes. The Taupo volcano seismic network has been modernised to better track any internal stirrings of the largest central North Island volcano. Equipment for measuring carbon dioxide released from volcanoes has been trialled successfully at White Island and Rotorua City, part of a programme to better understand the hot plumbing systems beneath our volcanoes (see page 4). And in the Wellington region, data communication links for GNS s old seismic network have been upgraded ahead of the network expansion that will begin in the next 12 months. The North Island continuous GPS network constructed for LINZ will underpin the new national Geodetic Datum 2000, and can directly and continuously measure the deformation of the land that leads to earthquakes. In the coming months, the goal of a more comprehensive national seismograph network for New Zealand will come several steps closer when GeoNet moves to a new satellite telemetry platform with Optus. An experienced international provider of satellite telemetry services, Optus will supply satellite links between New Zealand s expanding network of seismograph stations and strong-motion recorders, and GeoNet data centres (see page 8). The increasing flow of near real-time data will allow staff to evaluate earthquakes and volcanic eruptions as they unfold, providing a better-targeted rapid response during emergencies. Working together since 1997, GNS and Telstra NZ Ltd (now TelstraClear) pioneered the introduction of new data transfer protocols for satellite relay of information from seismographs and strong-motion recorders to data centres. Changes to the configuration of Telstra satellite services in Australia involve a change to the GeoNet service, and TelstraClear has facilitated a smooth migration to the new platform operated by Optus. To ensure continuity, the two systems will run in parallel until the end of August Existing and new stations monitoring seismic activity will be integrated into the new satellite telemetry network. The satellite network will also play an integral role in the future development of continuously recording Global Positioning System (GPS) stations to analyse the movement of land and build-up of strain that may presage earthquakes and volcanic eruptions. The new satellite telemetry system is just one aspect of the Earthquake Commission s commitment to aligning New Zealand s natural hazard monitoring and response with international best practice. Using new technology scarcely dreamt of a decade ago, scientists elsewhere (such as in Taiwan, see page 6) are expanding capabilities for monitoring natural disasters as they occur. Equally importantly, they are preparing communities to respond in a manner that will enhance their safety and minimise the economic loss to those who live and work in hazard-prone areas. Hugh Cowan, GeoNet Project Manager, GNS 2 GeoNet

3 VITAL PEOPLE IN THE GEONET PROJECT KEVIN FENAUGHTY Crises come and go, but with experience we are getting through them without too much angst. DION MATHESON KEVIN FENAUGHTY Manager: GeoNet Data Management Centre Kevin Fenaughty leads the team responsible for running the computers that receive, analyse and archive all the geophysical data collected by instruments in the GeoNet network. His team includes Mark Chadwick, Geoff Clitheroe and Penny Leach system developers whose work includes creating monitoring software for the duty officers on 24-hour call to ensure GeoNet data reaches the website. Kevin s team of data analysts, Lorena Cowan, Stephen Ede, Brian Ferris, Jan Harris, Michael Kopeykin and Diane Maunder, routinely locate all recorded New Zealand earthquakes, currently amounting to 15,000 events per year. When disaster strikes, it is Kevin s team, supported by GNS IT staff Andrew Carman, Steve Lawson, Ray Vercoelen and Roger Williams who will work together to monitor and restore the performance of field equipment, communications links and central computers. Fortunately, emergencies are rare. Most of the day-to-day work is maintaining archives of highquality data for research. Kevin points with pride to a recent advance making the entire New Zealand catalogue of over 200,000 earthquakes available on the GeoNet website. Kevin oversees the newest developments, but with over twenty years experience, he has responsibility for merging the legacy systems with the emerging technologies. Says Kevin: I am the expert in less fashionable computer languages and operating systems, but it is satisfying to extend their usefulness in parallel with our latest projects. Despite being in a position that has the potential for a lot of stress, Kevin prefers a working day with... no surprises. I like the quiet life! Crises come and go, but with experience we are getting through them without too much angst. Happiness is when everything is running smoothly. DION MATHESON GPS Network Coordinator, GNS Dion Matheson is responsible for the installation of continuous GPS stations for GeoNet. These stations are used to precisely measure the movement of the land surface invaluable information for hazard research. The way land is deformed provides clues to understanding earthquakes and volcanic activity. Phased in slowly over several years, a dense network of stations will be installed in the eastern and central North Island. LINZ has also contracted GNS to design and build a continuous-recording GPS network to support the development and operation of New Zealand s automated survey system. This survey control network will also be used by scientists to measure motions induced by geological forces. The elementary data will be available free of charge on the internet. The North Island network was completed in June 2003, and work has just started on the South Island network, and will keep Dion busy until December Dion has a Bachelor of Surveying from the University of Otago, and worked as a land surveyor in Nelson before joining GNS. He retains connections with Otago and is involved in a university project to measure vertical uplift of the Southern Alps. Dion also participates in other surveying projects, some of which have taken him to Tonga, Samoa and Niue. Dion says I love helicopter trips to remote and remarkable parts of New Zealand, going to places that are off the beaten track. It is interesting to meet and talk with people with diverse interests farmers, landowners and locals. I like the challenge of doing work that is leading edge, work that has never been done in New Zealand before. I like the challenge of doing work that is leading edge, work that has never been done in New Zealand before. UP CLOSE GeoNet 3

4 VOLCANOES EXHALING CO 2 PROVIDES AN EARLY WARNING Volcanoes release gases from magmas at depth during both eruptions and dormant periods. Monitoring the rate at which gases are released can help to predict changes in volcanic activity. At active volcanoes, often the emissions of sulphur dioxide (SO 2 ) are measured, but other gases, such as carbon dioxide (CO 2 ), can provide different and valuable information. Not all volcanic gases behave similarly in magmas. CO 2 is special in that it is not as soluble in magma as many other volcanic gases. So, as magma starts to move from deep in the crust toward the surface, CO 2 will start to come out, or degas, from the magma long before other gases. Therefore, increases in surface CO 2 emissions provide one of the first indications of changes in the magmatic system at depth. This information, coupled with changes in gas chemistry, changes in the ground surface of a volcano, and seismic activity can provide an early warning of an impending eruption. One of the goals of the GeoNet programme is to monitor CO 2 emissions from volcanic areas on a fairly continuous basis. Two new methods of monitoring CO 2 emissions have been launched at GNS in the past year. First, GNS is using accumulation chambers to measure the rate at which CO 2 seeps from the ground surface. Using this technique, CO 2 can be measured at many points across a region, such as Rotorua or the crater floor at White Island. With enough measurements, data can be contoured to provide maps that delineate areas with the highest rates of degassing, and which show overall emission rates for a given area. By measuring gas emission periodically, any changes will help to predict the behaviour of the magma at depth. GNS s second method involves measuring the aerial plume of CO 2 from active volcanoes. Using this method, the amount of additional volcanic CO 2 above regular atmospheric background levels is measured downwind of a volcano, allowing scientists to calculate volcanic emission rates. These rates, measured over time, provide information about deep volcanic processes. Measurements are currently being made regularly at White Island and Ruapehu volcanoes. The utility of CO 2 emission measurements goes beyond predicting increases in volcanic activity. These measurements will also help scientists understand how CO 2 is transferred between the Earth, the atmosphere, and the oceans. They will help to establish the natural rates of geothermal degassing, certainly of interest in terms of the Kyoto protocol for regulating greenhouse gas emmissions. Contact: Cindy Werner [email protected] ABOVE: CINDY WERNER AND CHRIS BROMLEY BACKGROUND: CINDY WERNER AND KAREN BRITTEN [email protected] [email protected] [email protected]

5 FRIENDS OF THE NETWORK MERIDIAN ENERGY LINKED TO GEONET Protecting the dams that form the mainstay of New Zealand s hydroelectric power generation system is vital. For more than 20 years, accelerographs have been operated on hydro storage dams to record their response during strong seismic shaking. In 2000, Meridian Energy replaced them with advanced digital instruments at Benmore, Aviemore, Tekapo and Pukaki dams, and at the Manapouri underground power station in Fiordland. The upgrade benefits both Meridian Energy and the wider community through GeoNet. Apart from being less expensive to run, the new instruments have alarms linked to Meridian s control centres. During an earthquake, Meridian staff receive automatic cellphone text messages and s alerting them to the level of groundshaking. This allows them to promptly carry out safety checks of their equipment and structures. The main public benefit is the new instruments have telemetry connecting them to the GeoNet data centres in Lower Hutt and Wairakei. When triggered by local seismic activity or by ground movements from large but distant earthquakes, the instruments immediately send in recordings of the event. GeoNet includes a network of 150 similar accelerographs throughout New Zealand that also dial into the GeoNet data centres. Using data from the accelerographs, and also from the nationwide seismograph network, GNS scientists can rapidly provide reports on the magnitude and location of an earthquake, as well as on the strength of ground-shaking at specific locations. Meridian can use these reports to determine the likely impacts of large earthquakes, not only on their dams, but on other assets. Meridian s instruments will provide valuable input to the national pool of information available for emergency response to large earthquakes. The data collected during such events will also form part of an invaluable shared resource for earthquake engineering research worldwide. Contact: Colin Dyer [email protected] GeoNet 5

6 WORLD STAGE TAIWAN: SETTING THE PACE FOR HAZARD RESPONSE Bordering active plate margins, New Zealand and Taiwan have much in common a high probability of powerful earthquakes, and mountainous terrain that is often deluged by heavy rain. In 1999, a magnitude 7.6 earthquake, centred near the town of Chi-Chi in central Taiwan, had devastating consequences over 2,500 people were killed or missing, and tens of thousands of homes collapsed. Even years after the earthquake, the Taiwanese are still feeling its effects. During typhoons, the huge landslides triggered by the earthquake remain potential sources of deadly mudslides and debris flows. Faced with these dangers, government agencies and the private sector in Taiwan have spent years building up their technical abilities to monitor hazards in real time and mitigate their effects. Their work has placed them at the forefront of hazard research. For example, while earthquakes cannot be reliably predicted, an earthquake early-warning system is now beginning to look technically feasible. The shock waves from an earthquake take time to spread outward from an earthquake s focus. Taiwan has tested a new system, using a strong-motion network, which can detect earthquakes and transmit data on them in less than 30 seconds. Cities more than 145 kilometres from the epicentre could be given more than 20 seconds early-warning time. In these few vital seconds before the strong shaking arrives, pre-programmed emergency measures could be triggered, saving many lives. High-speed trains could be slowed to prevent derailment, and gas pipelines shut off to reduce the risk of fire. Manufacturing operations could begin a controlled shut down, and computer facilities safeguarded to avoid losing vital databases. Such technical developments, no matter how promising on their own, however, must be taken on board by society if they are to do any good. To this end, Taiwan is developing NAPHM the NAtional Science and Technology Program for Hazards Mitigation aimed at reducing fatalities, loss of property and destruction of the environment. This programme will consolidate the efforts of national and local government agencies. In its early stages, databases on both the natural and socio-economic environments will be assembled and used to analyse hazard potential throughout Taiwan. Several pilot areas will be used to develop methods to assess risk, simulate hazard scenarios and develop hazard mitigation plans. One goal is to build a Taiwan Disaster Information Network, which will be a centre for reliable background information and real-time data on earthquakes and typhoons. This network will utilise the current telecommunications system to transmit real-time data and to rapidly disseminate warnings and advice to disaster response agencies and to the general public. The NAPHM programme will develop disaster management decision support systems to cover all aspects of hazard management, including mitigation measures, community preparedness, and emergency response and recovery. When disaster strikes, these support systems will guide those who must decide on the best measures to preserve lives and property. After six years of development under the auspices of NAPHM and the National Center for Research on Earthquake Engineering (NCREE), a mechanism for rapid assessment of damages and losses following earthquakes and floods is being established. For earthquake damage and loss assessment, the Haz-Taiwan system similar to the HAZUS system, but with distinct Taiwan characteristics provides the platform. Progressively more detailed and realistic assessment results will be presented formally to the Command Center at one hour, six hours, twelve hours and twenty-four hours after a major earthquake strikes. Information from the Central Weather Bureau s real-time earthquake reporting system will play a key role, particularly in the first few briefings. Maps of estimated potential inundation for individual river systems form the principal basis for assessing flood damage and loss. This is an interesting case of transferring research results to field operations. Contact: Dr Chin-Hsun Yeh, NCREE [email protected] 6 GeoNet

7 Staff of the Soil and Water Conservation Bureau are responsible for managing the response to landslides and debris flows that accompany strong earthquakes and torrential rain. The SWCB is among numerous agencies that will in future combine real-time monitoring with other information for emergency response and recovery planning. Photo courtesy Chen Chen-Yu, SWCB. GeoNet 7

8 AT THE EDGE OF SPACE GEONET TO EXPAND SATELLITE LINKS You might not think the best way to relay earthquake data from the Wairarapa to Wellington could be via outer space, Sydney, the floor of the Tasman Sea and Auckland. That seemingly circuitous route will become commonplace, however, when GNS completes the new National Seismograph Network, linked to GeoNet data centres by the Optus satellite telemetry system. At the heart of the new network for monitoring earthquakes and volcanic seismic activity are two types of instruments, accelerometers and seismometers. Strong-motion accelerometers measure how quickly the ground is set in motion, both horizontally and vertically, by earthquake waves. Engineers use these data to design earthquake-resistant buildings and structures, and information on the acceleration produced by an earthquake can help them analyse likely damage. The GeoNet accelerograph network is now largely complete, with 156 instruments sending information back to GeoNet data centres via cellular and conventional telephone networks. Seismometers record the various types of ground waves produced by earthquakes and re-awakening volcanoes. The seismograph stations will also be equipped with accelerometers together, the instruments will provide a continuous three-dimensional picture of seismic activity. Measurements are recorded on dataloggers, which will be connected to satellite dishes that beam the data to an Optus satellite. The Optus satellite is in geostationary orbit its altitude and speed match the rotation of the planet, so it stays in position above a fixed location on Earth. The satellite will relay signals from the instrument sites to the Optus Broadcast Operating Centre in Belrose, a suburb of Sydney, Australia. The Centre will in turn dispatch the data back to New Zealand via the floor of the Tasman Sea, along a fibre optic cable linking Sydney with Auckland. From Auckland, the data will be sent via terrestrial networks to the GeoNet data centres in Wairakei and Lower Hutt. Roundabout as that route seems, satellite communications represent the only cost-effective option for transmitting earthquake data from remote parts of New Zealand. The GeoNet data centres will receive the data barely ten seconds after it has been transmitted from the seismograph stations. Moreover, in the event of strong earthquake shaking, the Optus system can revert to a direct satellite link in both directions. The Optus satellite will beam signals directly to the GeoNet data centres, so data will continue to reach the centres even if terrestrial communication links are disrupted. Nine seismograph stations with Telstra satellite links have been running for several years, and were used to develop the system for transmitting seismic data using internet protocols. At the GeoNet data centres, the data from this pilot network are continuously recorded on workstations. If these computers detect any earthquakes, they in turn forward the data to programmes that can analyse the signals to determine the time, size and location of the earthquakes. Seismograph images from the data centre can be viewed, via high speed internet links, on a computer at the home of the duty officer, who can review earthquake locations any hour of the day or night. The officer can then issue earthquake reports via pagers, GeoNet s website, and fax. The entire network operates like a computer network, and uses standard internet protocols. In times of an emergency, workers using computers can readily monitor seismic data while they are checking incoming information from other sources. By early 2004, the new nationwide network of 40 seismograph stations, linked to the GNS data centres by the satellite telemetry system, will provide high quality data for earthquake research, and underpin the national emergency response to large earthquakes. Lead organisation in the GeoNet project COMING UP... INTERNATIONAL WORKSHOP: TSUNAMIS IN THE SOUTH PACIFIC RESEARCH TOWARD PREPAREDNESS AND MITIGATION When: September 2003 Where: Wellington Website: tsunami VOLCANOES AND SOCIETY SHORT COURSE When: October 2003 Where: GNS Wairakei Research Centre, Taupo Contact: Diane Tilyard [email protected] CONTACT DETAILS Website: [email protected] Address: Institute of Geological & Nuclear Sciences Limited, PO Box , Lower Hutt, New Zealand Editor: Eileen McSaveney GeoNet News is published twice yearly. Additional copies are available, at no cost for domestic delivery, from Leanne Dixon, GeoNet Administration Coordinator [email protected] Phone: Articles published in this newsletter may be quoted or reproduced as long as the Institute of Geological & Nuclear Sciences Limited is acknowledged as the source. GNS retains copyright on photographs, diagrams and illustrations and reproduction may only occur with prior written approval. Main funding agency: Co-funding agency: 8 GeoNet ISSN