Was the Midcontinent Rift part of a successful seafloor‐spreading episode?

The ~1.1 Ga Midcontinent Rift (MCR), the 3000 km long largely buried feature causing the largest gravity and magnetic anomaly within the North American craton, is traditionally considered a failed rift formed by isolated midplate volcanism and extension. We propose instead that the MCR formed as part of the rifting of Amazonia (Precambrian northeast South America) from Laurentia (Precambrian North America) and became inactive once seafloor spreading was established. A cusp in Laurentia's apparent polar wander path near the onset of MCR volcanism, recorded by the MCR's volcanic rocks, likely reflects the rifting. This scenario is suggested by analogy with younger rifts elsewhere and consistent with the MCR's extension to northwest Alabama along the East Continent Gravity High, southern Appalachian rocks having Amazonian affinities, and recent identification of contemporaneous large igneous provinces in Amazonia.

[1]  W. Gose,et al.  Reconnaissance paleomagnetic studies of Mesoproterozoic alkaline igneous complexes in the Kaapvaal craton, South Africa , 2013 .

[2]  D. Daniels,et al.  Upper crustal structure of Alabama from regional magnetic and gravity data: Using geology to interpret geophysics, and vice versa , 2013 .

[3]  M. Ritzwoller,et al.  Crustal and uppermost mantle structure in the central U.S. encompassing the Midcontinent Rift , 2013 .

[4]  M. Hamilton,et al.  Mesoproterozoic intraplate magmatic ‘barcode’ record of the Angola portion of the Congo Craton: Newly dated magmatic events at 1505 and 1110 Ma and implications for Nuna (Columbia) supercontinent reconstructions , 2013 .

[5]  G. R. Keller,et al.  Variations in Mid‐Continent Rift magma volumes consistent with microplate evolution , 2013 .

[6]  Z. Altamimi,et al.  A new velocity field for Africa from combined GPS and DORIS space geodetic Solutions: Contribution to the definition of the African reference frame (AFREF) , 2013 .

[7]  Maria Seton,et al.  Global continental and ocean basin reconstructions since 200 Ma , 2012 .

[8]  S. Stein,et al.  Learning from failure: The spree mid-continent rift experiment , 2011 .

[9]  Peter J. Berquist,et al.  Whole-rock Pb and Sm-Nd isotopic constraints on the growth of southeastern Laurentia during Grenvillian orogenesis , 2010 .

[10]  J. McLelland,et al.  Review of the Proterozoic evolution of the Grenville Province, its Adirondack outlier, and the Mesoproterozoic inliers of the Appalachians , 2010 .

[11]  W. Teixeira,et al.  A review of the tectonic evolution of the Sunsás belt, SW Amazonian Craton , 2010 .

[12]  D. Aslanian,et al.  A new starting point for the South and Equatorial Atlantic Ocean , 2010 .

[13]  M. Duchesne,et al.  What's the St. Lawrence Estuary Shallow Subsurface and Seafloor Made of? A Regional Appraisal Based on an Integrated Geophysical and Geological Study , 2010 .

[14]  S. Elming,et al.  Uplift deduced from remanent magnetization of a proterozoic basic dyke and the baked country rock in the Hoting area, Central Sweden: a palaeomagnetic and 40Ar/39Ar study , 2009 .

[15]  B. Weiss,et al.  No asymmetry in geomagnetic reversals recorded by 1.1-billion-year-old Keweenawan basalts , 2009 .

[16]  S. Elming,et al.  A palaeomagnetic and 40Ar/39Ar study of late precambrian sills in the SW part of the Amazonian craton: Amazonia in the Rodinia reconstruction , 2009 .

[17]  S. Elming,et al.  Direct dating of paleomagnetic results from Precambrian sediments in the Amazon craton: Evidence for Grenvillian emplacement of exotic crust in SE Appalachians of North America , 2008 .

[18]  W. Carlson,et al.  Mesoproterozoic plate tectonics: A collisional model for the Grenville-aged orogenic belt in the Llano uplift, central Texas , 2008 .

[19]  L. Heaman,et al.  Further refinement to the timing of Mesoproterozoic magmatism, Lake Nipigon region, Ontario , 2007 .

[20]  B. Pluijm,et al.  Restored transect across the exhumed Grenville orogen of Laurentia and Amazonia, with implications for crustal architecture , 2006 .

[21]  I. Dalziel,et al.  Eastern Laurentia in Rodinia: constraints from whole-rock Pb and U/Pb geochronology , 2003 .

[22]  S. King,et al.  Post-rift deformation of the Midcontinent rift under Grenville tectonism , 2002 .

[23]  B. Pluijm,et al.  Paleogeography of the Amazon craton at 1.2 Ga: early Grenvillian collision with the Llano segment of Laurentia , 2002 .

[24]  J. C. Green,et al.  The Mesoproterozoic Midcontinent Rift System, Lake Superior Region, USA , 2001 .

[25]  I. Dalziel,et al.  Laurentia‐Kalahari Collision and the Assembly of Rodinia , 2000, The Journal of Geology.

[26]  D. Gao,et al.  Along-Axis Segmentation and Growth History of the Rome Trough in the Central Appalachian Basin , 2000 .

[27]  D. Davis,et al.  Geochronology of the North American Midcontinent rift in western Lake Superior and implications for its geodynamic evolution , 1997 .

[28]  S. Nicholson,et al.  Rift-wide correlation of 1.1 Ga Midcontinent rift system basalts: implications for multiple mantle sources during rift development , 1997 .

[29]  Donald C. Adams,et al.  Precambrian Basement Geology of the Permian Basin Region of West Texas and Eastern New Mexico: A Geophysical Perspective , 1996 .

[30]  R. Blakely.  Potential theory in gravity and magnetic applications , 1996 .

[31]  W. F. Cannon,et al.  Crustal‐scale thrusting and origin of the Montreal River monocline‐A 35‐km‐thick cross section of the midcontinent rift in northern Michigan and Wisconsin , 1993 .

[32]  W. F. Cannon.  The Midcontinent rift in the Lake Superior region with emphasis on its geodynamic evolution , 1992 .

[33]  A. Green,et al.  Geophysical investigations and crustal structure of the North American Midcontinent Rift system , 1992 .

[34]  P. Hoffman.  Did the Breakout of Laurentia Turn Gondwanaland Inside-Out? , 1991, Science.

[35]  M. Gordon,et al.  Collision-induced rifting: The Grenville Orogeny and the Keweenawan Rift of North America , 1986 .

[36]  A. Cox,et al.  Paleomagnetic Euler poles and the apparent polar wander and absolute motion of North America since the Carboniferous , 1984 .

[37]  G. R. Keller,et al.  Evidence for a major Late Precambrian tectonic event (rifting?) in the Eastern Midcontinent Region, United States , 1982 .

[38]  L. Pesonen,et al.  9: Paleomagnetism of Keweenawan rocks , 1982 .

[39]  H. Halls,et al.  Remagnetization in Keweenawan rocks. Part II: lava flows within the Copper Harbor Conglomerate, Michigan , 1981 .

[40]  E. Irving.  Paleopoles and paleolatitudes of North America and speculations about displaced terrains , 1979 .

[41]  C. G. Chase,et al.  Precambrian plate tectonics: The midcontinent gravity high , 1973 .

[42]  I. Zietz,et al.  Aeromagnetic Study of the Midcontinent Gravity High of Central United States , 1971 .

[43]  Seongryong Kim,et al.  American Geophysical Union. All Rights Reserved. Evidence of Volatile-Induced Melting , 2022 .