More than 1,000 ft (305 m) of four-way closure exists on the doubly plunging Red anticline, which is exposed at the eastern front of the Wet Mountains, Colorado. This anticline is the only one with large closure exposed in the Denver basin area. The Precambrian basement, intermittently exposed through the overlying Pennsylvanian Fountain Formation, is folded concentrically with the overlying Paleozoic and Mesozoic section, as shown by structure contours and cross sections. The anticline is steeply asymmetric to the west, toward the mountains, and the east flank dips 10° eastward toward the Denver basin. The anticline is exposed in an 18-mi-long (29-km-long) window in the Wet Mountains thrust, and it plunges northwest and southeast under the window's edges.

Recent seismic work on the Rampart Range thrust along the southeastern flank of the Front Range, north of the Wet Mountain, permits about 6 mi (10 km) of overhang and allows an underlying structure similar to the 5 mi wide (8 km) Red anticline. The trace of the Rampart Range thrust plunges north and south from its midpoint at Monument, Colorado, and may reflect the double plunge of such a subthrust anticline.

In both the Wet Mountains and the southeastern Front Range, a system of normal faults is present about 6 mi (10 km) west of the mountain front. These faults probably are listric, and their downthrown west blocks probably collapsed down the west side of an anticline below the thrust.

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