Crustal-Scale Seismic Structure From Trench to Forearc in the Cascadia Subduction Zone

2017 ◽  
Vol 122 (9) ◽  
pp. 7311-7328 ◽  
Author(s):  
Sampath Rathnayaka ◽  
Haiying Gao
Keyword(s):  
Subduction Zone ◽  
Cascadia Subduction Zone ◽  
Seismic Structure

The northern Cascadia subduction zone at Vancouver Island: seismic structure and tectonic history

1990 ◽  
Vol 27 (3) ◽  
pp. 313-329 ◽  
Author(s):  
R. D. Hyndman ◽  
C. J. Yorath ◽  
R. M. Clowes ◽  
E. E. Davis
Keyword(s):  
Continental Shelf ◽  
Subduction Zone ◽  
Deep Ocean ◽  
Vancouver Island ◽  
Ocean Basin ◽  
Cascadia Subduction Zone ◽  
Accretionary Wedge ◽  
Seismic Structure ◽  
Tectonic History ◽  
Wide Range

The structure and Tertiary tectonic history of the northern Cascadia subduction zone have been delineated by a series of new multichannel seismic lines acquired across the continental shelf to the deep sea, combined with adjacent land multichannel seismic data and results from a wide range of other geophysical and geological studies. The top of the downgoing oceanic crust is imaged for a remarkable distance downdip from the deep ocean basin to a depth of 40 km beneath Vancouver Island. The reflection depths are in good agreement with seismic refraction models and Benioff–Wadati seismicity. Two broad reflective bands imaged as dipping gently landward at depths of about 15 and 30 km on the land lines merge to a single reflector band offshore. They may represent underplated oceanic material or, alternatively, they may not be structural but may be zones of contrasting physical properties, perhaps representing trapped fluid. Two narrow terranes, the Mesozoic marine sedimentary Pacific Rim Terrane and the Eocene marine volcanic Crescent Terrane, have been thrust beneath, and accreted to, the margin in the Eocene, about 42 Ma, near the start of the present phase of subduction. They provide a landward-dipping backstop to the large sediment wedge accreted since that time. The deformation front is characterized by mainly landward-dipping thrust faults that cut close to basement. This result and the mass balance of the incoming sediment compared with that present in the accreted wedge suggest that there is little subduction of sediment into the mantle. The Tofino Basin sediments, up to 4 km in thickness, have been deposited on the continental shelf over the accreted terranes and the developing accretionary wedge.

ASSESSING THE UTILITY OF δ13C AND BULK GEOCHEMISTRY IN ESTUARIES ALONG THE CASCADIA SUBDUCTION ZONE FOR COASTAL PALEOSEISMOLOGY

2017 ◽  
Author(s):  
Robert J. O'Donnell ◽  
◽  
Andrea D. Hawkes ◽  
Chad S. Lane ◽  
Simon E. Engelhart ◽  
...  
Keyword(s):  
Subduction Zone ◽  
Cascadia Subduction Zone

scholarly journals A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis

2021 ◽  
Vol 261 ◽  
pp. 106922
Author(s):  
Alan R. Nelson ◽  
Christopher B. DuRoss ◽  
Robert C. Witter ◽  
Harvey M. Kelsey ◽  
Simon E. Engelhart ◽  
...  
Keyword(s):  
Subduction Zone ◽  
Cascadia Subduction Zone ◽  
Megathrust Earthquakes ◽  
Rupture Model

Electrical structure of the central Cascadia subduction zone: The EMSLAB Lincoln Line revisited

2014 ◽  
Vol 402 ◽  
pp. 265-274 ◽  
Author(s):  
Rob L. Evans ◽  
Philip E. Wannamaker ◽  
R. Shane McGary ◽  
Jimmy Elsenbeck
Keyword(s):  
Subduction Zone ◽  
Cascadia Subduction Zone ◽  
Electrical Structure
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