editorial - sfu.caenvironments of the alps (france, italy, austria, switzerland, germany) and coast,...
TRANSCRIPT
EditorialCurrent events can overwhelm you at all levels. The more intense the event, the more profound and wide ranging is the potential for insight. The disasters of 2011 caused by earthquakes and storms provided immense potential. The potential for insight was magnified by the proliferation of video recorders in pocket devices, and the propensity (perhaps drive) to share the recordings through web 2.0 media. Providing learned context to the images of the natural laboratory is both an opportunity and societal necessity. This edition of Risky Ground highlights educational and creative tools to develop that learned context.
Overwhelming personal events held back the 2011 spring edition of Risky Ground. That edition is now available and I encourage you to check out its review of the ‘Mapping Unstable Ground’ workshop, announcements of the October International Symposium on 'Submarine Mass Movements and Their Consequences' and September Slope Stability 2011 conference, and summary of the Centre for Natural Hazard Research riskbased landuse guide initiative.
Bert Struik, [email protected]
Centre for Natural Hazard Research, Simon Fraser University
Stuff that Happened
Matthieu landslide-dam Lake drains on Dominica, West Indies On the night of Thursday, July 28, 2011, the landslide dam impounding Matthieu River at its junction with Layou River was breached. Alert residents in the
town of Layou where the Layou River reaches the Caribbean Sea notified government officials at about 12:30 AM that the river had risen suddenly and began flooding adjacent lowlands. The town is about 6 km downstream from the junction of the Matthieu and Layou rivers. No one was reported killed or injured by the flood waters. Significant damage occurred at Hillsborough Agricultural Facility and tourist facilities along the lower Layou River valley. Due to the rugged terrain of the island nation, the main transportation routes are along the shoreline with a few connecting across the central highlands. One of these connecting routes is now impassable due to the loss of the central 16m long span of the Gleau Chand Bridge. The volume of water released in the flood exceeded 1.325 x 106 m3, which is the estimation made for flooding after breaching of a 1997 landslide dam on the Layou River. The Hillsborough Agricultural Facility and the Gleau Chand Bridge were unscathed by this earlier event.
The Matthieu landslide dam and the lake formed behind it had persisted since its occurrence on November 25, 1997. The lake was known to some locally as “Miracle Lake” due to the long period of its apparent stability. Google Earth imagery shows the lake and surrounding area as they were prior to the July 28, 2011 breach. The circumstances surrounding formation of the landslide dam and the persistence of the resulting lake were documented in May 2010 by a paper published in the journal, Environmental & Engineering Geoscience, entitled “The Formation and Persistence of the Matthieu LandslideDam Lake, Dominica, W.I.” (Vol. 16, no.2, p. 7389).
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2011 September 21 - Fall edition
View looking from the Layou River valley (Layou River flows from right to left across bottom of view) at the breached Matthieu landslidedam. The dam formerly filled the gap between the two vertical cliffs at the mouth of the Matthieu River. (Photo by Inspector Christopher Laville, Special Services Unit, Commonwealth of Dominica).
By Jerome V. De Graff and Arlington James
geoNatHaz 2011The “geoNatHaz” project (www.geonathaz.unito.it) is a Transatlantic Exchange Partnership (TEP) established to enhance international earth science competence in natural hazards research. During 2010 and 2011, geoNatHaz offered a unique, innovative curriculum based on four major types of activity:
1) Organization and recognition of didactic activities. Classic natural hazards case studies have been selected and evaluated for inclusion in problem–based educational activities. Classroom, laboratory, and fieldbased activities are based on these case studies and are offered to earth science and engineering geology students. All geoNatHaz activities have been accredited through the normal vetting and approval procedures of the participating universities.
2) Student and staff exchanges. To date, geoNatHaz has supported a total of 24 students (7 long term and 17 short termmobility) and six faculty members within the EUCanada consortium of universities. Students were involved in the European and Canadian summer schools, which have focused on natural hazard and mitigation studies in the mountain environments of the Alps (France, Italy, Austria, Switzerland, Germany) and Coast, Rocky, and St. Elias Mountains (western Canada). Longterm
students pursued research projects involving geomorphic mapping, geostructural analysis of deepseated gravitational slope deformations, digital photogrammetry of unstable slopes, and paleoseismic trenching.
3) Development of transferable technical skills and competence in natural hazards. Partnerships among university, government, and privatesector scientists in four countries (Canada, Italy, France, and Greece) provide expertise and material support for field activities. The GIS and Geomatic Laboratory (Geositlab) of the University of Turino and the Geotechnics and Photogrammetry Laboratory at Simon Fraser University support students involved in project activities The distinction between hazard and risk, and the environmental differences between Canada and Europe are important topics addressed during the summer schools. The second largest landslide in history in Canada happened one week before the 2010 geoNatHaz field school, providing a unique openair laboratory for studying large slope instabilities. geoNatHaz students also examined natural hazards in the Mount Blanc area, European Alps where the risk to inhabitants, tourists, and infrastructure is much higher than in Canada.
4) Dissemination of outcomes and implementation of sustainability of the project. The geoNatHaz project has been showcased at scientific meetings and conferences (CanQua 2009, MAEGS 17, GeoItalia 2009, AIGEO 2009, EGU 2010 and 2011) and its activities have been publicized through the electronic and print media. The (geoNatHaz promotional postcards and posters, a website, ra,dio and TV interviews, and newspaper articles). The project has proved to be of interest to scientists, professionals, and the general public. Improvement of services for exchange students and sustainability of geoNatHaz activities beyond the current threeyear funding period are being pursued.
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geoNatHaz students and faculty and two paleoseismic trenches in southwest Yukon.
Marco Giardino, [email protected] NatRisk Interdipartimental Research Centre, University of Torino, Italy
John Clague, [email protected] Centre for Natural Hazard Research, Simon Fraser University
Historical Natural Disasters
1880 Haney Slide and landslide-generated tsunami, BCThe 1880 landslide at Haney was one of the first major landslides reported by European settlers of Southwestern British Columbia (BC). On the afternoon of January 3rd a 35mhigh cut bank of Fraser River failed between modern Carshill Street and then Haney Bypass, 40 km east of Vancouver. The failed mass was up to 450 m wide and 300 m long, and had a volume of ~1 Mm6. Debris rapidly entered Fraser River, temporarily blocking it and producing a reportedly 20mhigh tsunami that travelled tens of kilometres up and downriver. Directly across the river at Derby the wave cleared trees along the river’s edge and stripped branches on trees farther inland as high as 6 m up. Two people witnessed the landslide: James Sinclair, from his school several hundred metres west of the slide, and Anne Haney, from her home 400 m east of the slide. Accounts of the event printed in local papers describe the sound accompanying the landslide as cannonfirelike sound and mention that trees on the surface remained nearly vertical even as they were carried into the river.
The landslide was never investigated in detail, but its occurrence is likely the result of geologic and climatic factors. The failed mass was entirely in silty to sandy marine clay of the Fort Langley Formation, deposited ca. 13,000 years ago when the Fraser Lowland was isostatically depressed below sea level. Following emergence of Fraser Lowland and progradation of Fraser River delta, Fraser River incised the deposit producing a steep cliff that provided toe release for failure. Sandy interbeds capped by clay likely assisted failure by accommodating preferential groundwater flow and increased porewater pressures; newspaper reports shortly after the event mention discharge of water from a coarse layer within the clay. Precipitation likely triggered the landslide. Precipitation in the months preceding the event was much higher than normal and included rainfall on a 60 cm snowpack a few weeks before the event. A similarsized scar of older, but unknown age occurs 2.5 km downstream and Port Hammond, and two smaller scars occur between it and Haney Slides.
The landslide resulted in minimal destruction, but the resulting tsunamis greatly increased the extent and amount of loss. Eight hectares of farmland were lost during the landslide. The subsequent tsunami, however, destroyed boats, bridges and wharfs over 25 km upstream. One boat was carried ~100 m inland and left stranded atop a 12mhigh hill. At Derby the tsunami destroyed ~6 ha of timber and severely injured William Edge, who was clearing brush. Edge was found entangled in wood debris several metres off the ground and later died of his injuries.
In 1880, Fraser Lowland was sparsely populated, particularly in areas upstream of New Westminster including Haney and Derby. Population and development have increased greatly in the 130 years since the landslide. Riverside land in Haney, including the scar of the 1880 landslide, presently supports dense residential neighbourhoods. A large amount of transportation infrastructure is located along Fraser River in the vicinity of Haney. Because of increased exposure, a similar event in present day would result in much higher economic and life loss. The 1880 event was the only one of its kind in historic time and resulted in stabilization of the only remaining high escarpment on this part of the river.
Tsunami from subaerial landslides occur episodically in Southwestern BC and adjacent Washington State. The 1880 Haney Slide was the first of fourteen historically documented events in the region. The
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deadliest event occurred in 1905 at Spence’s Bridge, BC when a terrace of glaciolacustrine sediments slumped into Thompson River and generated a tsunami that claimed 15 lives. The most recent landslidegenerated tsunami in Canada resulted from a ~3 Mm3 debris/rock avalanche on 04 December 2007 that entered Chehalis Lake, producing a tsunami with runup exceeding 35 m.
Nick Roberts, [email protected]
Centre for Natural Hazard Research, Simon Fraser University
Upcoming Events
Risk-based Land-use guide exercise and workshopDuring fall 2011, SFU's Centre for Natural Hazard Research and its partners will host three separate events to complete a draft riskbased landuse guide for southwest British Columbia municipalities.
Technical Workshop
On Wednesday September 28, 2011, several technical experts are invited to review the existing draft guide and recommend how to make the guide relevant, practical and useable.
Landuse Decision Simulation Exercise
On Friday November 8, 2011, an exercise will be hosted at the Justice Institute of British Columbia's Simulation Laboratory to evaluate the efficacy of the guide for real life landuse decision scenarios for municipalities of the lower mainland of British Columbia and to learn from your colleagues. Municipal staff and academics dealing with landuse decisions are encouraged to participate. The registration limit is 32, because of the simulation centre size.
Landuse Guide Workshop
On Thursday December 8, 2011, an open workshop will provide participants the opportunity to evaluate the draft landuse guide. A broad range of stakeholders in reducing disasters through riskbased landuse decisions are encouraged to participate. The registration limit is 80. Knowledge shared at these events will be used to further develop the draft landuse guide to reduce risk from disasters. The guide will
be webbased, accessible for improvement and available in 2012.
The events are described on the CNHR website workshops pages and an information circular is available for download. Contact Bert Struik for information and registration.
Bert Struik [email protected]
Centre for Natural Hazard Research, Simon Fraser University http://www.sfu.ca/cnhr/
International Summer School on Rockslides and Related Phenomena: Kokomeren River Valley (Kyrgyztan)Rockslides (bedrock landslides) are among the most hazardous natural phenomena in mountainous regions. Though relatively rare, in comparison with landslides in nonlithified soils, they pose a threat to the vast areas due to enormous amount of rocks involved (sometimes up to billions of cubic meters), their high mobility and ability to create large natural dams. The latter cause inundation of the valleys upstream and have the potential for catastrophic outburst floods downstream.
Numerous rockslides and rock avalanches of different types ranging from a few millions to more than l billion cubic meters in volume are concentrated in Kokomeren River valley (Central Tien Shan) within a limited area of about 40x60 km at a oneday trip distance from Bishkek. Most sites are located near a road along Kokomeren River and require only few hours of hiking to access. Due to arid climate and lack of vegetation rockslide morphology is well preserved and clearly visible. Some of rockslide deposits are deeply dissected by erosion that allows studying their internal structure in detail. Along with the bedrock slope failures several very large landslides in nonlithified Neogene and Quaternary deposits occur in the adjacent neotectonic depressions. Impressive evidence of river damming and of powerful outburst floods caused by rockslide dam breach could be found in the study area.
Besides rockslides and landslides, the study area is extremely rich in manifestations of Neotectonics and Quaternary tectonics such as active faults, one of which had been ruptured during the 1992 M7.3
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Suusamyr earthquake, and numerous examples of tilted and folded preNeogene planation surface.
The aim of the International Summer School is to demonstrate rockslides and long runout rock avalanches of different morphological types, intact and eroded rockslide dams, internal structure of rockslide deposits, effects of river damming along with various methods of their study (identification, mapping, dating, detail analysis of rockslide internal structure and grainsize composition) to students and young landslide researchers. The annual InternationalSummer School supported by IGL http://www.iclhjq.org) has been organized in 20062009 and in 201 l. Previous field training courses were attended by participants from Czech Republic, Italy, USA, Germany, France, Belgium, New Zealand, Austria, Switzerland, Russia, Tajikistan and Kyrgyzstan.
The 2012 training course is planned to be carried out from August 15 to August 30. The participation fee is EURO 400, which includes all costs at the site: camping (in tents; though some tents can be provided by organizers, participants will be asked to bring their own tents and sleeping bags), food, local transportation, guidebook. Organizers will provide help obtaining a visa if necessary. Participants will be picked up at the arrival desk of the Bishkek airport. Bishkek is connected with Moscow, London, Istanbul and Urumchi by direct flights. Arrival via Almaty or Tashkent is possible as well.
Participation fee should be paid either in advance by bank transfer or by cash upon the participant's arrival. Transferred fees of those, who will not be able to come, will be refunded in full except for the amount charged by bank for the transfer. Further details of bank transfer will be provided later.
Summer School Guidebook (75dpi resolution) can be downloaded from the International Consortium onLandslides homepage:http://www.iclhq.org /Summer_School_Guidebook2009.pdfWe plan to replace it in MarchApril, 2012 with a revised version that will be available at the samehomepage.
For further information contact:
Dr. Alexander StromGeodyamic Research Center branch of the Hydroproject Institute. Volokolamskoe highway, 2, 125993, Moscow, Russiaemail: [email protected]
Dr. Kanatbek AbdrahmatovInstitute of Seismology, National Academy of Science, Asanbay 52/1, Bishkek 720060, Kygyzstanemail: [email protected]
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Risky Ground publishes news stories and information on topics of interest to researchers and practitioners in natural hazards and their risks to people, infrastructure and the environment. It is distributed by email as an electronic version quarterly, near the start of each season, by the Centre for Natural Hazard Research at Simon Fraser University, Burnaby, British Columbia, Canada. Copies are hosted for download at http://www.sfu.ca/cnhr/newsletters
Opinions published in this newsletter do not reflect official positions of Simon Fraser University or its Department of Earth Sciences.
Submissions are accepted in digital format up to 3 weeks prior to publication, and should be sent by email to the editors for consideration. Articles can be up to 750 words and include pictures and graphics up to 8 x 12 cm (to fit within a column).
Centre DirectorJohn Clague
Managing editorBert Struik
Content editorNick [email protected]
Centre for Natural Hazard Researchhttp://www.sfu.ca/cnhr
Department of Earth SciencesSimon Fraser University8888 University Drive
Burnaby, British Columbia, Canada V5A 1S6
Centre for Natural Hazard ResearchThe Centre for Natural Hazard Research (CNHR) is an SFUbased institute housed in the Department of Earth Sciences. Its mandate is to conduct innovative research on geophysical processes that are a threat to the population and economic infrastructure of Canada. CNHR has a western Canada focus, but the research findings and developed methodologies are applicable to the whole of Canada and to the international community. A key element of the Centre is the inclusion of public policy research on how to effectively transfer the results of scientific research to the people who need and can use it.
CNHR hosts talks at SFU by hazard and risk researchers and practitioners. We welcome your suggestions for potential speakers for the spring and fall of 2011. The Centre also sponsors or cosponsors workshops on a variety of topics of interest to professionals and students in British Columbia. Information on the next workshop, scheduled for April 15, 2011 is included in this issue.
We welcome short updates from readers and members on their research activities and meetings of interest.
John Clague
Director, Centre for Natural Hazard Research
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