Surface observations along the southern margin of the Wind River Range indicate that motion on the Wind River and Continental faults controlled depositional patterns and lithologic character of early Eocene syntectonic sediments. The stratigraphic sequence consists of alluvial plain, lake margin, deltaic, and alluvial fan units. Subsequent movement on the Wind River fault warped this sequence into a monocline 2 mi (3.2 km) long. This structure dies out to the northwest and southeast along the Wind River fault and is overlain by undeformed middle Eocene sediments. Clast composition and paleocurrent studies of post-early Eocene conglomerates indicate that there were additional sources for coarse clastics formed by subsequent uplift in the Precambrian core of the range.

Tectonic implications of these interpretations are: (1) early motion on the Wind River fault controlled the margin of Eocene Lake Gosiute and generated a distal sediment source to the east; (2) last motion on the Wind River-Continental fault system was episodic and principally over by the end of early Eocene; (3) the Continental fault, now a post-Miocene collapse

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feature, was a tear fault with a vertical component up on the north; (4) the Wind River fault is a zone consisting of segments that moved separately; and (5) there are at least two unmapped fault zones along which the core of the Wind River Range was uplifted.

These interpretations suggest that compression in the Wyoming foreland continued significantly later than early Eocene. An imbricate thrust model is proposed to accommodate these observations and interpretations.

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