Preliminary results of geologic mapping and structural studies raise questions about terrane accretion models as presently applied to interior Alaska and suggest an alternative model of tectonic development. Among the regional geologic patterns and problems pertinent to any model for interior Alaska are (a) the present Z-shaped configuration of the northern Cordilleran fold-and-thrust belt (CFTB), (b) the means by which 450 km of dextral strike-slip is dispersed on splays of the Tintina fault system, (c) the original continuity of the crystalline terranes of interior Alaska and their pre-Tintina Z-shaped distribution paralleling that of CFTB, and (d) the origins of two belts of deep-water deposits with mafic-igneous and locally ophiolitic associations--one outboard and th other inboard of the crystalline belt. The proposed model features (1) a relatively straight and passive North American margin with a Proterozoic to Middle Devonian sedimentary prism that underwent intermittent extension and volcanism in its distal part, (2) a Devonian-Mississippian continental arc at the outer edge of (1) and flanked cratonward by (3), an extending and rapidly subsiding basin also developed on (1) but containing Mississippian to Triassic deep-water sediments and abundant mafic-igneous material. Collapse and structural telescoping of the margin and intense reactivation of the continental arc occurred in Jurassic through Early Cretaceous time as oceanic crust converged with North America, and exotic terranes were accreted to the outboard side of arc. Oroclinal Z-bending f Cordilleran trends probably accompanied Late Cretaceous and earliest Tertiary strike-slip movement on the Tintina and other fault systems based and rearranged.

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