Natural Arch -- Grapevine Hills Trail, Big Bend NP TX
N 29° 23.991 W 103° 12.125
13R E 674452 N 3253631
A small natural arch on the Grapevine Hills Trail in Big Bend National Park
Waymark Code: WMTZZK
Location: Texas, United States
Date Posted: 01/30/2017
Views: 4
This small natural arch is located high up the cliffs at the spot where the Balanced Rock trail splits off from the Grapevine Hills Trail in Big Bend National Park.
This arch looks like it is made of sandstone, or a sedimentary layer of ash or sea floor that overload the magma dome that one day 38 million years ago rose up and fractured this area in to boulders.
A sign at the Grapevine Hills Trail (from which the Balanced Rock trail branches) reads as follows:
"GRAPEVINE HILLS TRAIL
The easy 2 mile round-trip trail follows a sandy wash through the jumble of boulders. After reaching a low pass, find a “window” of boulders by hiking another hundred yards along the ridge to the right.
This trail enters a realm of petrified fire. Here, under enormous pressure, a molten rock ballooned up beneath the earth surface. As erosion stripped away overlying layers the exposed domes fractured into a moonscape of giant boulders.
Grapevine Hills is a laccolith - a mushroom shaped intrusion of magma.
As the laccolith slowly cooled and hardened into granite, the overlying sedimentary layers began to wear away."
Photo of the Arch by itself?: yes
Type of Arch: Water Eroded
Type of Material:
sedimentary rock softer than the volcanic granite of the lava dome
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Visit Instructions:
You must post a picture of you with a GPSr or Geocaching/Waymarking attire/equipment and the subject arch in the background.