Geological Survey Bulletin 1393 The Geologic Story of Arches National Park

Courthouse Towers Area

About 2.3 miles from the entrance station is a turnoff and parking area at the south end of the Park Avenue trail (stop 2), which is about 1 mile long and ends at another parking area 1.7 miles farther north. An interesting hike is best made from south to north in a downhill direction, and hikers generally meet the cars of relatives or friends awaiting them at the northern parking area. The trail begins in a canyon cut in the soft Dewey Bridge Member and walled by high fins of the Slick Rock Member (fig. 27), but farther north the canyon is floored by the bare Navajo Sandstone. The avenue was named from the resemblance of the east wall to a row of tall buildings. Atop the west wall, just to the left of the view in figure 27, are two balanced rocks (fig. 28). The one on the left, which resembles somewhat the head of an Egyptian queen, is offset to the right along a bedding plane, and this offset may have been caused by an earthquake.

PARK AVENUE, viewed to the north along trail. (Fig. 27)

BALANCED ROCKS ON SOUTH WALL OF PARK AVENUE, at south end of trail. (Fig. 28)

As we progress toward Courthouse Towers proper, lofty fins and monoliths lie mostly on our left, and to the right are fine distant views of the La Sal Mountains (stop 4). A general view of the Courthouse Towers is shown in figure 29, and closeups of two of the named rock sculptures—the Three Gossips and Sheep Rock—are shown in figures 30 and 31. Just beyond Sheep Rock, which some think resembles the Sphinx, we see "Baby Arch," shown in figure 15.

COURTHOUSE TOWERS, viewed to the northwest from point on park road about three-fourths of a mile northeast of the south end of Park Avenue trail. Sandstone towers are Slick Rock Member resting on Dewey Bridge Member, which also forms foreground. Three Gossips at upper left, Sheep Rock just beyond. The Organ and Tower of Babel are on right. (Fig. 29)

THE THREE GOSSIPS, shown at upper left of figure 29. (Fig. 30)	SHEEP ROCK, shown on center-left skyline in figure 29. (Fig. 31)

Five miles from the entrance station, the road crosses Courthouse Wash on a modern bridge (stop 6)—a distinct improvement over the two tracks in the sand we used in 1946. The Courthouse syncline, named after the wash, extends northwestward through here. (See figs. 8, 9, 20.) About a mile west of the bridge, Professor Stevens found another pothole arch. A mile and a half north of the bridge is stop 7, where attention is called in the booklet to the vast area of "petrified dunes" east of the road, which are simply dunelike exposures of the crossbedded Navajo Sandstone formed originally by the cementation of a vast area of sand dunes. My view of these was taken about 1 mile beyond the stop (fig. 32).

PETRIFIED SAND DUNES, looking northeast from park road 2.7 miles north of Courthouse Wash. The Navajo Sandstone was once a huge sandpile of dunes laid down by winds during an arid interval, so it is interesting to note that the irregularly weathered sandstone once again resembles a pile of crossbedded dunes. See also figure 35. (Fig. 32)

West of the road between the petrified dunes and The Windows section, the Entrada Sandstone, particularly the Dewey Bridge Member, has been weathered into grotesque spires and pinnacles resembling the so-called "hoodoos and goblins" in Goblin Valley State Park, just north of Hanksville, Utah. Typical examples of "hoodoos and goblins" are shown in figure 33 (near stop 8). It seems reasonable to assume that some of these spires are the skeletal remains of former arch abutments. From here may be seen North and South Windows and Turret Arch on the skyline to the northeast (figs. 37-40).

"HOODOOS AND GOBLINS," weathered from Dewey Bridge Member, viewed northwest from park road about 2-1/2 miles north of Courthouse Wash. (Fig. 33)