Small Format Aerial Photography:
Goemmer Butte, Colorado
By Steven Wade Veatch
Introduction
In the shadow of the legendary Spanish Peaks near La Veta, Colorado an unusual volcanic plug, Goemmer Butte, rises more than 840 feet from the Cuchara Valley floor. The butte was named after the Goemmer family who homesteaded nearby in the 1860s. The butte is composed of a dark latite, a porphyritic rock intermediate in character between trachyte and andesite — the extrusive equivalent of monzonite. There is little or no quartz in the crystalline groundmass. The latite is characterized by phenocrysts of plagioclase and potassium feldspar in almost equal amounts. There are scattered medium to coarse-grained mafic inclusions. (Penn and Lindsey, 1996).
Goemmer Butte is unique in that it marks the only site in the immediate Spanish Peaks area where magma vented to the surface. Breccia, composed of fragments of Cuchara sandstone and latite, is exposed on the south and west sides of the plug where it had erupted from a central fissure or diatreme (Lindsey, 1995). Thin dikes of latite extend from the plug and intrude the breccia. Goemmer Butte likely post-dates the intrusion of the stocks of West and East Spanish Peak by some time (Penn, Pers. Comm 1999).
The Spanish Peaks were formed during the late Oligocene to early Miocene when masses of molten lava intruded into layers of sedimentary rock. The Spanish Peak intrusive rocks range in composition from lamprophyres to granite porphyries with diverse mineralogies. A number of volcanic dikes formed when molten rock was injected into cracks and fissures in the regional sedimentary rocks. Over time the softer sedimentary layers eroded away to expose the more resistant rock of the Spanish Peaks. These dikes are now exposed as long and thin walls (1-100 feet in width). More than 400 separate dikes have been identified.
The Spanish Peaks marked the boundary between the seemingly endless eastern plains and the southern Rocky Mountains, and were important landmarks that that guided Indians, Spanish settlers, French trappers, and American explorers. The twin mountain peaks had religious meaning for the Ute and other Indians of the area. They called the mountains " Wahatoya", or breasts of the earth. The Spanish knew the mountains as Las Cumbres Españolas. Diego de Vargas, the governor of Spanish New Mexico, was one of the first Europeans to see the Spanish Peaks in 1694 (Gregory, 1996).
| View from the summit of West Spanish Peak of Goemmer Butte and Profile Dike. A variety of intrusive features dominate the landscape. Photo courtesy B. Penn. |
| View of the Spanish Peaks from Lathrop State Park on the south side of CO 10 looking SSW. The Spanish Peaks (West Spanish Peak is 13,626 feet in elevation, and East Spanish Peak is 12,683 feet in elevation) lie on the western edge of the Great Plains in south central Colorado. Photo courtesy of B. Penn. |
Kite Aerial Photographs
| East Spanish Peak, which intruded after West Spanish Peak, is on the left; West Spanish Peak is on the right. The dark rock in front of the Spanish Peaks is Goemmer Butte (pronounced "Gimmer"), a volcanic plug that intruded into the Cuchara Formation as part of the Spanish Peak intrusives. The Eocene age Cuchara Formation is an arkosic conglomerate. Photo date 3/99 by J.S. Aber. |
| View NNW showing a dike separating Cross Mountain in the background from HR Carson reservoirs. A former river channel, lined by willows and a few cottonwood trees, is seen in the front left corner. Photo date 3/99 by S. W. Veatch. |
| In this low-oblique view Indian Creek is seen winding its way through ranchland owned by the Goemmer family. Cottonwood trees and willows grow on either side of the creek. The water level is low at this time of year. The depth of the eroded river channel reveals that Indian Creek has been a larger creek in the past. North is toward the top of the photo. Photo date 3/99 by S. W. Veatch. |
| County road 421 viewed to the northwest. A series of parallel dikes extend along the top left. The upper portion of a ravine, which exposes the Cuchara Formation, can be seen in the lower left corner. Photo date 3/99 by S. W. Veatch. |
Photo Acquisition
Kite aerial photography (KAP) presents a bird's eye view and is one of the oldest forms of remote sensing (gathering data about an object from a distance) and has several important advantages. Not only is KAP easy to use, it also provides an inexpensive method to acquire photographs and supplies a permanent record. KAP can play important roles in scientific surveys, land-use surveys, documenting landscapes, and habitat analysis. KAP is especially useful in documenting change at a site by providing a chronological sequence of aerial photographs over a span of time.
The photographs for this project were taken on March 22, 1999 between 2:30 and 3:30 p.m. The afternoon was partly cloudy with a breeze between nine and 11 mph. A delta kite was flown at an elevation of about 250 feet above the ground on a 250-pound dacron line. A 15-foot tail was attached to the kite to improve flight stability. This type of kite is very easy to launch and works well under gentle to moderate wind (10 - 20 mph). A radio-controlled KAP rig held a 35-mm point-and-shoot camera that could be pointed 360° in the camera's horizontal position (pan). The camera's vertical position (tilt or depression angle) could be moved between 0° (horizontal) to 90° (straight down).
| Kite | Type | delta kite |
| Size | 11 foot wing span | |
| Air surface | 30 ft2 | |
| Weight | 19 ounces | |
| Kap rig | Radio controlled with picavet suspension that holds a camera cradle with 360 degree pan and 90-degree tilt | |
| Camera | Olympus Stylus Epic point-and-shoot camera with 35 mm fixed-focal-length lens | |
| Film | Elite Chrome 200 slide film | |
A Hewlett Packard PhotoSmart scanner was used to scan color slides with 24-bit color at a resolution of 600 dpi — adequate for low-elevation aerial photographs. The conversion of the slides to a digital file format (JPEG — Joint Photographic Experts Group) allows the application of computer processing, handling, storage, analysis, and image enhancement.
Acknowledgments
I would like to thank Dr. James Aber for traveling to Colorado to show me the finer points of kite aerial photography. This report is part of an earth science course requirement (ES 555 Small Format Aerial Photography) completed at Emporia State University.
References
Gregory, L., 1996, Colorado Scenic Guide: Southern Edition, Johnson Books: Boulder, CO p. 182-1894.
Penn, B. S. and Lindsey, D. A., 1996, Tertiary igneous rocks and Laramide structure and stratigraphy of the Spanish Peaks region, south-central Colorado: Road Log and description form Walsenburg to La Veta (first day) and Le Veta to Aguilar (second day), Colorado Geological Survey: Open-file report 96-4, p.9.
Penn, Brian, pers. comm.: Department of Geological Sciences, University of Texas at El Paso, El Paso, TX April 8, 1999, (interview).
Lindsey, D.A., 1995, Geologic map of the Cuchara quadrangle, Huerfano County, Colorado: U.S. Geological Survey: Miscellaneous Field Studies Map MF-2283, scale 1:24,000.
April 19, 1999