Virginia Dale Area

1 route · Outer cap rock monzogranite of the Virginia Dale ring-dike complex · 6,977 ft

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How well located

Crag only 1

No route here has its own point yet. The map pin is the crag. At the wall? Survey it: 30 seconds per route.

Rock, from the geologic map

Outer cap rock monzogranite of the Virginia Dale ring-dike complex — monzogranite. Mesoproterozoic, about 1,600 to 1,000 million years old.

Pinkish-gray, medium-grained, porphyritic biotite monzogranite, similar in all respects to inner cap rock monzogranite (YgVi) except that phenocrysts are smaller and better aligned, and biotite-rich streaks are more common; color index generally 7 to 9. Contact with inner cap rock monzogranite is gradational

This is the map unit under this crag's map point, read from the 1:100,000 sheet (Workman and others, 2018, U.S. Geological Survey Scientific Investigations Map 3399). The point can be a few hundred metres from the rock, a cliff often stands on the line between two units, and at that scale a line on the map is about 100 m wide on the ground, so the wall itself may be the neighbouring unit. Every crag on this unit: Outer cap rock monzogranite of the Virginia Dale ring-dike complex. Geology data: Macrostrat (CC BY 4.0), serving USGS and Colorado Geological Survey maps.

On the map since 1907

The USGS has mapped this ground since 1907. 20 historical sheets cover this crag's map point; the oldest is below.

Thumbnail of the 1907 USGS sheet covering Virginia Dale Area — **USGS 1:125000-scale Quadrangle for Livermore, CO 1907** · U.S. Geological Survey · 1907 · 1:125,000 sheet
USGS Historical Topographic Map Collection · Public domain · the record · placed by its coordinates

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Hidden as soon as you tell us, everywhere it appears, before anyone reviews it.

Public domain, U.S. Geological Survey. The sheet shows the ground as the survey found it then, which is why a trail or road you know may be missing. Every sheet over this point, 1907 to 1980: USGS topoView.

In print since 1877

1877 Geologic Map of Colorado (Hayden), high-resolution scan · F. V. Hayden; scan by the Colorado Geological Survey · 1877

The whole-state sheet of the 1877 atlas, scanned at full resolution by the state survey and free to download.

Colorado Geological Survey (publication HM-01-04) · Public domain · read it
Geological and geographical atlas of Colorado and portions of adjacent territory · F. V. Hayden, U.S. Geological and Geographical Survey of the Territories · 1877

The first geology anyone drew of this ground. Hayden's survey mapped the state in the 1870s; these are the sheets, with the rock units coloured as they understood them then.

Internet Archive (Brigham Young University copy) · Public domain · read it

Free to read: public domain or government work. About Fort Collins as a whole, not this wall. More in the reading room.

From the archives

Photographs of this area held by the Library of Congress, oldest first. Every one carries the Library's own "no known restrictions on publication"; anything else is left out.

After the Explosion of a Ten-Ton Blast above Fort, Collins, Colorado · Keystone View Company · 1908 · stereograph
Library of Congress, Prints & Photographs Division · Public domain · the record · found by place name, not yet checked

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