TY - CHAP
T1 - Synthesis of Results from the CD-ROM Experiment
T2 - 4-D Image of the Lithosphere Beneath the Rocky Mountains and Implications for Understanding the Evolution of Continental Lithosphere
AU - CD-ROM Working Group
AU - Karlstrom, Karl E.
AU - Whitmeyer, Steven J.
AU - Dueker, Ken
AU - Williams, Michael L.
AU - Bowring, Samuel A.
AU - Levander, Alan R.
AU - Humphreys, E. D.
AU - Randy Keller, G.
AU - Andronicos, Christopher
AU - Bolay, Nicholas
AU - Boyd, Oliver S.
AU - Cather, Steve
AU - Chamberlain, Kevin
AU - Christensen, Nick
AU - Crowley, Jim
AU - Crosswhite, Jason
AU - Coblentz, David
AU - Eshete, Tefera
AU - Erslev, Eric
AU - Farmer, Lang
AU - Flowers, Rebecca
AU - Fox, Otina
AU - Heizler, Matt
AU - Humphreys, Gene
AU - Jessup, Micah
AU - Johnson, Roy
AU - Karlstrom, Karl
AU - Kelley, Shari A.
AU - Kirby, Eric
AU - Levander, Alan
AU - Beatrice Magnani, M.
AU - Mahan, Kevin
AU - Matzal, Jennie
AU - McCoy, Annie
AU - Meyer, Grant
AU - Miller, Kate
AU - Morozova, Elena
AU - Pazzaglia, Frank
AU - Prodehl, Claus
AU - Read, Adam
AU - Quezada, Oscar
AU - Roy, Mousurni
AU - Rumpel, Hanna Maria
AU - Selverstone, Jane
AU - Sheehan, Anne
AU - Stevens, Liane
AU - Shaw, Colin A.
AU - Shoshitaishvili, Elena
AU - Smithson, Scott
AU - Snelson, Cathy
N1 - Publisher Copyright:
© 2005 by the American Geophysical Union. All rights reserved.
PY - 2013/3/19
Y1 - 2013/3/19
N2 - The CD-ROM experiment has produced a new 4-D understanding of the structure and evolution of the lithosphere of the southern Rocky Mountain region. We identify relicts of at least four subduction zones that were formed during assembly of dominantly oceanic terranes in the Paleoproterozoic. Crustal provinces with different geologic histories correspond to distinct mantle velocity domains, with profound mantle velocity contrasts associated with the ancient sutures. Typically, the transitions between the velocity domains are tabular, dipping, extend from the base of the crust to depths of 15&200 km, and some contain dipping mantle anisotropy. The present day heterogeneous mantle structure, although strongly influenced by ancient compositional variations, has undergone different degrees of partial melting due to Cenozoic heating andlor hydration caused by transient plumes or asthenospheric convection within the wide western U.S. active plate margin. A high-velocity mafic lower crust is present throughout the Rocky Mountains, and there is ~10-km-scale Moho topography. Both are interpreted to record progressive and ongoing differentiation of lithosphere, and a Moho that has changed position due to flux of basalt from the mantle to the crust. The mafic lower crust evolved diachronously via concentration of mafic restite during arc formation (pre-1.70 Ga), collision-related differentiation and granite genesis (1.7s1.62 Ga), and several episodes of basaltic underplating (1.45-1.35 Ga, ~1.1 Ga, and Cenozoic). Epeirogenic uplift of the western U.S. and Rocky Mountain regions, driven by mantle magmatism, continues to cause reactivation of the heterogeneous lithosphere in the Cenozoic, resulting in differential uplift of the Rocky Mountains.
AB - The CD-ROM experiment has produced a new 4-D understanding of the structure and evolution of the lithosphere of the southern Rocky Mountain region. We identify relicts of at least four subduction zones that were formed during assembly of dominantly oceanic terranes in the Paleoproterozoic. Crustal provinces with different geologic histories correspond to distinct mantle velocity domains, with profound mantle velocity contrasts associated with the ancient sutures. Typically, the transitions between the velocity domains are tabular, dipping, extend from the base of the crust to depths of 15&200 km, and some contain dipping mantle anisotropy. The present day heterogeneous mantle structure, although strongly influenced by ancient compositional variations, has undergone different degrees of partial melting due to Cenozoic heating andlor hydration caused by transient plumes or asthenospheric convection within the wide western U.S. active plate margin. A high-velocity mafic lower crust is present throughout the Rocky Mountains, and there is ~10-km-scale Moho topography. Both are interpreted to record progressive and ongoing differentiation of lithosphere, and a Moho that has changed position due to flux of basalt from the mantle to the crust. The mafic lower crust evolved diachronously via concentration of mafic restite during arc formation (pre-1.70 Ga), collision-related differentiation and granite genesis (1.7s1.62 Ga), and several episodes of basaltic underplating (1.45-1.35 Ga, ~1.1 Ga, and Cenozoic). Epeirogenic uplift of the western U.S. and Rocky Mountain regions, driven by mantle magmatism, continues to cause reactivation of the heterogeneous lithosphere in the Cenozoic, resulting in differential uplift of the Rocky Mountains.
KW - Core-mantle boundary
KW - Geology, Structural-Rocky Mountains
KW - Geophysics-Rocky Mountains
KW - Orogeny-Rocky Mountains
UR - http://www.scopus.com/inward/record.url?scp=84951128985&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84951128985&partnerID=8YFLogxK
U2 - 10.1029/154GM31
DO - 10.1029/154GM31
M3 - Chapter
AN - SCOPUS:84951128985
SN - 0875904181
SN - 9780875904191
SP - 421
EP - 441
BT - The Rocky Mountain Region
PB - American Geophysical Union
ER -