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Updated: Oct 13, 2010
IGCP Project 559 - Seismic Images
North America
GLIMPSE Transect, Great Lakes region, Canada/USA
The transects cross the Great Lakes between Canada and the USA. GLIMPCE (Great Lakes International Multidisciplinary Program on Crustal Evolution) transects cross the Keweenawan Rift System (Lake Superior), an arcuate structure extending 2000 km from Kansas to central Michigan, with up to 25 km of syn-rift volcanics and interlayered sediments plus an additional 10 km of post-rift sediments. In Lake Huron, a transect crosses the Grenville Front Tectonic Zone, the northwestern edge of the Grenville Orogenic belt
Western Canada Sedimentary Basin Transect, Alberta, Canada
Transect crosses the Alberta basement of western Canada. The transect shows two layers, the lower, Precambrian crystalline basement of the Canadian Shield and the upper, an overlying veneer of sedimentary strata that constitutes the pertroleum-rich Western Canada Sedimentary Basin (WCSB).
Southern Appalachian Mountains Transect, USA (I)
Transect crosses the Virginia Piedmont with the Blue Ridge Province overlying Grenville basement. Web site provides additional data on the Southern Appalachian Mountains transect as well as information on the Appalachian UltraDeep Core Hole project.
Southern Appalachian Mountains Transect, USA (II)
Transect crosses the Virginia Piedmont with the Blue Ridge Province overlying Grenville basement. Web site provides data and references.
Southern Appalachian Mountains Transect, USA (III) (PDF file)
Transect crosses the Virginia Piedmont with the Blue Ridge Province overlying Grenville basement. The results show a zone of crustal weakness that was the continental edge during the Precambrian and which persisted as a zone of tectonic activity during later times.
Grenville Province, mid-continental USA (I) (PDF file)
PDF of paper published with results from seismic transects across the Grenville Province. Transects include those from COCORP's central Ohio survey (OH-1 & OH-2) and GLIMPCE (Great Lakes International Multidisciplinary Program on Crustal Evolution). Results indicate the Grenville Front is an east-dipping suture that is the western limit of a relatively simple assemblage of laterally extensive terranes, accreted by plate tectonic processes.
Grenville Province, mid-continental USA (II) (PDF file)
PDF of paper published with further results from seismic transects across the Grenville Province. Transects include those from COCORP's Illinois, Indiana and central Ohio surveys. Results discuss implications of west-dipping intra-Grenville structures and indications that these mark a major collision zone within the eastern mid-continent.
Grenville Province, mid-continental USA (III) (PDF file)
PDF of paper published with further results from seismic transects across the USA's mid-continental area, including the Western Granite-Rhyolite and Eastern Granite-Rhyolote areas and the Central Plains area. Transects include those from COCORP's. Missouri, Illinois and Indiana surveys and highlight mid-continent layering throughout the crust.
The Trans-Canada Transect, Canada (PDF file)
Transet is a composite transect that crosses Canada from east to west. The Trans-Canada crustal cross-section spans 4 billion years of crustal evolution and emphasizes the large-scale pattern of sequential collisions that result in deformation and continental growth.
Kapuskasing Structural Transect, Ontario, Canada
Transect across the Kapuskasing structural zone within the Archaean Superior Province, a region where rocks formed in the lower continental crust are now exposed at the surface. The Kapuskasing structural zone was caused by right-lateral transpression along NE-trending faults and NW-over-SE thrusting caused by plate collisions at the Superior Province margin.
Abitibi-Grenville Transect, Quebec-Ontario, Canada
Transect crosses the Late Archaean Abitibi greenstone belt (part of the southern Superior Province, the central core of the North American craton) and the Mesoproterozoic Grenville Orogen. Results show convincing evidence for lateral convergence during the Archaean. Grenville Orogen structures now extend across two continents from southern Sweden to southern Mexico and the orogen is one of the greatest collisional belts ever formed.
Trans-Hudson Orogen Transect, Manitoba-Saskatchewan, Canada
Transect crosses Early Proterozoic orogenic belts formed by Proterozoic crustal accretion and collision of older Archaean microcontinents. The seismic transect shows a complete Trans-Hudson Orogen section that is characterized by a zone of Early Proterozoic rocks sandwiched between the variably reworked Archaean Superior Craton and Hearne-Rae Craton.
Western Superior Craton Transect, Ontario, Canada
Transect crosses the western part of the Archaean Superior Province, the nucleus of the North American continent. Results show oceanic crust, island arcs, sedimentary prisms and continental fragments were accreted successively from north to south against the southern margin of the cratonic nucleus.
Lithoprobe SNORCLE transect, Western Canada
Transect from the Slave Craton to the Pacific Ocean and crossing the western Canadian sedimenraty basins. The western part crosses the Rocky Mountains,Cordillera and Coast Belt.
Surrency Bright Spot, Georgia, USA (PDF file)
Transect crosses the inferred Aleghanian suture zone running through southeastern Georgia. Transect shows unusually strong midcrustal reflectors and shows evidence of underthrusting of upper crustal rocks having occurred during suturing of Florida to North America. Study looks at 3D structure interpreted from P-wave and S-waveanalysis near the transect area.
LITHOPROBE East Transect, Newfoundland, Canada
Transect crosses onshore Newfoundland and the exposed Appalachian orogen; formed during closing of the Iapetus Ocean. Traverse shows structures related to the development of the Appalachian orogen, including the Humber, Dunnage, Gander, Avalon terranes and the Red Indian Line and the Dry Cove Thrust.
Eastern Canadian Shield (Escoot) Transect, Labrador offshore margin, Canada
Traverse is located across offshore Labrador and Quebec. The transect, the Eastern Canadian Shield Onshore-Offshore Transect (ECSOOT), crosses two large Archaean cratons, the Nain and Superior Cratons, a smaller block of Archaean crust (now in core of the southeastern Churchill Province) and five Proterozoic orogens. Two orogens (the New Quebec and Thorngat orogens) suture the three Archaean blocks; the others record the progressive southerly accretion of juvenile crustal material to the growing Laurentian continent.
Eastern continental margins Transect, Eastern Canada
Alternative ESCOOT website
Series of offhore transects off the coast of eastern Canada. Transects show features seen in the ESCOOT survey as well as recent structures associated with the modern continent - ocean boundary.
Southern Cordillera Transect, British Columbia, Canada
Transect crosses the Southern Cordillera of western Canada. Transect shows process of accretion of terranes that comprise plate fragments, island arcs, or microcontinents, within the Canadian Cordillera.
Puget Sound Transect, Seattle, northwest USA (I) (PDF file)
Transect crosses the Cascadia subduction zone of northwestern US and southwest Canada. Transect shows a cross section of seismicity across an active subduction zone.
Puget Sound Transect, Seattle, northwest USA (II) (PDF file)
Transect crosses the Cascadia subduction zone of northwestern US and southwest Canada. Transect shows the Seattle uplift, the Seattle fault, the Kingston arch, the transpressional Southern Whidbey Island Fault Zone and the Puget Lowlands area; an area lying on a north-directed thrust sheet.
North American Western Margin Transects, Pacific Ocean margin, USA - Canada
Nine transects across the west margin of North America. Common tectonic elements identified along these transects all relate to convergent continental margins and include: 1. actively subducting oceanic crust; 2. accreted oceanic/arc lithosphere of Mesozoic through Cenozoic ages; 3. Cenozoic accretionary prisms; 4. Mesozoic accretionary prisms; 5. backstops to the Mesozoic prisms; 6. undivided lower crust. Four of the transects cross subduction-zones, and five cross a transform-fault (San Andreas fault).
Cornell University, Institute for the Study of the Continents (INSTOC), Consortium for Continental Reflection Profiling (COCORP)
LITHOPROBE - Canada's national multidisciplinary geoscience project
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