Scientific, Economic and Social Contributions

Le projet pancanadien en sciences de la terre Canada’s national geoscience project

: A New View of the Continent Beneath Our Feet

What is ?

Why ?

How does work?

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ITHOPROBE

ITHOPROBE

ITHOPROBE

Canada's national, collaborative, multidisciplinary Earth science project established in 1984 to develop acomprehensive understanding of how the Canadian landmass and continental margins developed throughgeological time the last 4 billion years. We are , Earth's relatively cold, strong, rigidouter shell which is typically 100 km or more thick.

To gain a basic understanding of the continent on which we live,from which we derive resources and which generates naturalhazards such as earthquakes and volcanoes.

To obtain regional background information useful to mining,petroleum, and other resource industries.

Multidisciplinary within the Earth sciences:Spearheaded by seismic reflection techniques that are usedto image the lithosphere to more than 100 km depthGeology, geochemistry, dating of rocks, other geophysicsCollaborative across Canada:

- 32 University Earth science departments;- 5 offices of the Geological Survey of Canada;- 8 provincial/territorial geological surveys;- participation from 27 petroleum, 8 base- and precious-metalmining, 8 diamond and 5 uranium companies

Decentralized research activitiesStudy Areas:

- 10 “transects” were selected to represent globallysignificant tectonic processes

- Transects traverse from Vancouver Island to Newfoundland,and from the northern U.S. to the Yukon, NWT and northernLabrador

- Transects span geological time from 4 billion years ago tothe present

- Board of Directors for policy; scientific committees for advice- Secretariat at University of British Columbia for coordination

probing the lithosphere

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Natural Sciences and EngineeringResearch Council of Canada [NSERC]:

~$54M over 20 years- Geological Survey of Canada [GSC]:

~$27M over 20 years- Industry and provincial/territorial

geological surveys when studies arein their spheres of interest:~$22M over 20 years

- Other NSERC and other grants toindividual scientists; studentfellowships:~$8M over 20 years

Who funds ?-

LITHOPROBE

Deploying seismographs in northern BC

Vibroseis trucks generating seismic reflection data nearStewart, BC during the L SNORCLE transectITHOPROBE

Pacific Ocean Coast Mtns Rocky Mtns Southern Alberta Manitoba NW Ontario L. Superior Quebec Quebec Newfoundland Atlantic OceanSouthern OntarioSaskatchewan

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Delamination

Grenville Front

Active subduction zoneActive subduction zone

Earthquake zoneEarthquake zone

Magmatic arcMagmatic arc

Accreted terranes thrustover cratonic crust

Accreted terranes thrustover cratonic crust

Thrust-and-foldbelt

Thrust-and-foldbelt

Sedimentarybasin overlying

deformed Archean crust

Sedimentarybasin overlying

deformed Archean crustTrapped

microcontinentTrapped

microcontinentCrustal-scale

thrustingCrustal-scale

thrusting

Archean suturingand

fossil subduction

Archean suturingand

fossil subduction

Archean suturingand

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Archean suturingand

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collisionFold-and-thrust

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Accretion andDelaminationAccretion andDelamination

Modern passivemargin

Modern passivemargin

Failedcontinental

rift

Failedcontinental

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Crustal rootCrustal root

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Victoria Vancouver Vernon Lethbridge Flin Flon Thunder Bay Matagami Montreal St.John’sLa Ronge

Interpretation

Reflection fabricReflection fabric

Velocity modelsVelocity models

2700 My-old delamination

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The Trans-Canada Crustal Cross-Section

Seismic reflection images from Line 48 (circled on the map and noted by dashed box below).The seismic image (top panel) and its interpretation (lower panel) of the northern Abitibi beltand the Opatica plutonic belt show the results of a collision of continental crust that occurred2.7 billion years ago . The remarkablereflections that extend into the mantle are a fossil signature of subduction and/or crustaldelamination. This profile provides direct evidence that plate tectonics has operated since atleast the late Archean. The collision helped generate the greenstone belts that host the richmineral resources of Ontario and Quebec. The colours in the lower panel represent differentgeological units interpreted from geological, geochemical, and geophysical data.

[Calvert et al., 1995; Ludden and Hynes, 2000]

Techniques

How does the Earth change over time? How are continents formed?How do those processes affect us?

LITHOPROBE’s work over the past two decades has had a major impact on ourunderstanding of Canada’s geological and tectonic history, as well as of the globalprocesses that drive the evolution of our planet. Eight of the ten study areas link toform a grand transect that spans the continent. Although the seismic profiles do notappear to trace a continuous line across the country, the offsets vanish when faultzones, rock ages, and tectonic linkages are considered.

The map divides Canada into general “tectonic age”, the time since the last episodeof major deformation. LITHOPROBE seismic lines are shown with those lineshighlighted that are used for the Trans-Canada crustal cross-section. The cross-section below includes seismic reflection, seismic refraction, and interpreted profiles.The profiles span 4 billion years of crustal evolution and emphasize the large-scalepattern of sequential collisions that result in deformation and continental growth.

LITHOPROBE focuses multidisciplinary

research on a carefully chosen study area.The new investigations are led by seismicprofiling that provides structural andcompositional information to full crustal depths(and sometimes much deeper). The seismicimages provide a framework within which thecontributions of other Earth Science disciplinescan be more effectively interpreted.The multidisciplinary approach involvesvirtually all branches of solid Earth Scienceincluding - geology

- geophysics- geochemistry- geochronology

Seismic Methodsa) Seismic Reflection

b) Seismic Refraction

Sound vibrations generated by vibroseis trucksreflect off of material interfaces that havecontrasting properties. This reflected energy isrecorded at the surface and used to producedetailed images of the structure of the crustand upper mantle (see middle panel below).

Vibrations generated by explosive sources (orthe vibroseis trucks) are recorded at distancesup to 800 km. These waves are “bent” (e.g.,red dashed lines in schematic figure) bygradual changes in rock properties. The dataare used to generate models that constrainstructural, compositional, and thermalproperties. The lower panel below displaysmodels of the speed (km/s) the sound wavestravel through the Earth.

AG48

Near-vertical incidence reflectionRefraction / Wide-angle reflection

Near-vertical incidence reflectionRefraction / Wide-angle reflection

Near-vertical incidence reflectionRefraction / Wide-angle reflection

Near-vertical incidence reflectionRefraction / Wide-angle reflectionNear-vertical incidence reflection

Refraction / Wide-angle reflectionNear-vertical incidence reflectionRefraction / Wide-angle reflection

Near-vertical incidence reflectionRefraction / Wide-angle reflection

Southern CordilleraTransect

Southern CordilleraTransect

Alberta BasementTransect

Alberta BasementTransect

Trans-Hudson OrogenTransect

Trans-Hudson OrogenTransect

Western Superior& GLIMPCETransects

Western Superior& GLIMPCETransects

Abitibi-GrenvilleTransect

Abitibi-GrenvilleTransect

Lithoprobe EastTransect

Lithoprobe EastTransect

For more information and copies of this poster, see www.lithoprobe.caPrepared by: P. Hammer, A. van der Velden, F. Cook, and R. Clowes

S-NSW-NES-NESE-WNWS-N

ABITIBIOPATICANEMISCAU

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CDP 1100020003000400050006000700080009000

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Discovery and exploration

Regional information for industry

Technological innovation and transfer of science and technology to the private sector

New resources and mitigation of hazards

Training the next generation of earth scientists

Education and public awareness of science and technology

A new approach to collaborative science in Canada

Vast areas of Canada have been mapped from the surface to depths exceeding 100 km.The collaborative, multidisciplinary approach has yielded great advances in understanding the structure anddevelopmental history of Canada. Applications of these investigations range from resource discoveriesto advancements in our understanding of global processes that control the evolution of our planet.

The success of the program has resulted in L serving as a model for other network projectsin Canada and around the world.

New and improved understanding of Earth history provides the resource industry with practical andtheoretical information that enhances their exploration capabilities.

Instrumentation and software developed through L has beentransferred to industry (e.g., seismographs now built by Scintrex Ltd.,magnetotelluric recorders now built by Phoenix Geophysics Ltd.).emonstration of the applicability of the high resolution seismic reflectiontechnique to mining exploration:

- base-metal exploration in Ontario and Quebec- mapping diamondiferous kimberlite dykes in the NWT

(a scientific and industry first)- exploration for uranium deposits in northern Saskatchewan.

L data and interpretations contributed to a petroleumdiscovery off the west coast of Newfoundland.

studies on the west coast of Canada provided dataand a framework for better understanding the mega-thrust earthquake hazard in the region.GSC scientists are continuing and extending such research in the region, thus contributing to a muchmore fundamental understanding of the hazard and how it may affect the region.

Over 450 graduate and undergraduate students, postdoctoral fellows and research associates havelearned their specific skills in an environment of multidisciplinary collaboration.

ducational material (e.g., posters, image archives, regional factsheets) developed and used from high schools to universities.

Children's book (ages 9-14), based on results from .Enhanced the visibility and relevance of the Earth sciences.

Fostered an unprecedented degree of cooperation among Earthscientists in universities, federal and provincial/territorialgeological surveys, and the mining and petroleum industries.

Spawned a new and healthy atmosphere of scientificcooperation among geologists, geophysicists, andgeochemists; enhances results beyond those that could beachieved through any one subdiscipline.

ITHOPROBE

ITHOPROBE

ITHOPROBE

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Ron Clowes, Director www.lithoprobe.caLithoprobe Secretariat clowes@lithoprobe.ubc.caUniversity of British Columbia 604.822.41386339 Stores RoadVancouver, BC V6T 1Z4

ITHOPROBE

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ITHOPROBE

Contact Information

Le projet pancanadien en sciences de la terre Canada’s national geoscience project

: Scientific, Economic and Social Contributions

LITHOPROBE Trill 3D seismic reflection imagefrom Sudbury, Ontario. Ore body (red) detected.

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