Crustal structure of Wrangellia and adjacent terranes inferred from geophysical studies along a transect through the northern Talkeetna Mountains

J.M.G. Glen; J. Schmidt; L. Pellerin; D.K. McPhee; J.M. O’Neill

doi:10.1130/2007.2431(02)

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Crustal structure of Wrangellia and adjacent terranes inferred from geophysical studies along a transect through the northern Talkeetna Mountains

J.M.G. Glen·J. Schmidt·L. Pellerin·D.K. McPhee·J.M. O’Neill

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Abstract

Recent investigations of the Talkeetna Mountains in south-central Alaska were undertaken to study the region's framework geophysics and to reinterpret structures and crustal composition. Potential field (gravity and magnetic) and magnetotelluric (MT) data were collected along northwest-trending profiles as part of the U.S. Geological Survey's Talkeetna Mountains transect project. The Talkeetna Mountains transect area comprises eight 1:63,360 quadrangles (∼9500 km 2 ) in the Healy and Talkeetna Mountains 1° × 3° sheets that span four major lithostratigraphic terranes ( Glen et al., this volume ) including the Wrangellia and Peninsular terranes and two Mesozoic overlap assemblages inboard (northwest) of Wrangellia. These data were used here to develop 2½-dimensional models for the three profiles.

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J.M.G. Glen, J. Schmidt, L. Pellerin, D.K. McPhee, J.M. O’Neill. 2007. Crustal structure of Wrangellia and adjacent terranes inferred from geophysical studies along a transect through the northern Talkeetna Mountains. https://doi.org/10.1130/2007.2431(02)

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