ROBERT M. KIRKHAM, GEOLOGIST, P.G., C.P.G.siterepository.s3.amazonaws.com/00175201202171011207942.pdf · San Juan Volcanic Region west of the town of Del Norte (Gries, 1985; Brister

ROBERT M. KIRKHAM, GEOLOGIST, P.G., C.P.G. 5253 County Road 1 South

Alamosa, CO 81101

Phone: 719-587-0139 email: [email protected]

June 27, 2011 Don Van Wormer, City Manager City of Monte Vista 4 Chico Camino Monte Vista, Co 81144 RE: mineral remoteness letter for Montez Park in the south half of section 31, T. 39 N., R. 8 E., NMPM, located in the City of Monte Vista, Rio Grande County, Colorado Dear Mr. Van Wormer,

This mineral remoteness letter was prepared in response to the Professional Services Agreement between the City of Monte Vista and GeoLogical Solutions dated May 31, 2011. The letter summarizes my evaluation of the mineral potential of Montez Park in the City of Monte Vista. It is my understanding that this mineral assessment is needed to facilitate the purchase of the property by the City. Appendix A is a legal description of this property, which includes about 2.09 acres.

Introduction: Montez Park is located within the City of Monte Vista, which is situated in the San Luis Valley in south-central Colorado (see Figure 1 at end of letter). The park is in the eastern part of Monte Vista and is at an altitude of about 7,655 feet above sea level (Figure 2). Highway 160 and 285 borders the northern side of the property, and the San Luis Rio Grande Railroad (formerly called the Denver and Rio Grande Western Railroad) is on the southern side of the property. Historically, the property has been used as public park (Figure 3).

As shown in Figure 4, the surface rights and mineral rights to Montez Park, as well as all land in close proximity to the park are privately owned. The nearest federal lands and federal mineral rights are more than three miles southwest of the easement. The State of Colorado has surface ownership of lands about 1 ½ miles east of the park (Figure 4) and has mineral rights as close as about ½ mile west-northwest of the park (Figure 5).

My evaluation of the potential for mineral development beneath Montez Park included (1) a review of published geologic maps, geologic reports, and mining records; (2) the U.S. Bureau of Land Management’s Master Title Plats for T. 39 N., R. 7 E. and T. 39 N., R. 6 E., their 1:100,000-scale, surface and mineral management map of the Del Norte 30 x 60 minute quadrangle, and their Land and Mineral Legacy Rehost System (LR2000); (3) a reconnaissance field investigation conducted on June 22, 2011 of the park; and (4) examination of the on-line database for active mines (Colorado Division of Reclamation Mining & Safety, 2011), for water wells (Colorado Division of Water Resources, 2011); and for oil and gas wells (Colorado Oil and Gas Conservation Commission, 2011).

No new subsurface information (e.g. drill holes or geophysical studies) was collected, and no assays or chemical analyses of rock, soil, or water were performed. This evaluation was conducted in a manner consistent with the level of care and skill ordinarily exercised by other professional

mineral remoteness evaluation of Montez Park for City of Monte Vista page 1

consultants under similar circumstances. No other representations, express or implied, and no warranty or guarantee are included or intended.

Geologic Setting: Your property is within the northern part of the Rio Grande Rift, which is a geologically young, pull-apart tear in the earth’s crust that extends northward from Mexico, through central New Mexico, and into Colorado at least as far as Leadville (Figure 6). The Rio Grande Rift is important to this assessment, because the geologic processes active during rifting affect the depth and type of bedrock beneath the park, as well as much of the sedimentary deposits that overlie the bedrock.

Rifting initiated about 26 million years ago and is still active today. San Luis Basin is the largest basin or structurally downdropped block within the northern part of the Rio Grande Rift (Figure 6). It extends from Poncha Pass southward to just beyond Taos, and it includes both the San Luis Valley and the Taos Plateau. Structurally, San Luis Basin is an east-tilted half graben. As the basin was tilted down to the east, it filled with sediments eroded from the adjacent San Juan and Sangre de Cristo Mountains and with local and regional volcanic flows. The rift-related sedimentary and volcanic rocks are included in the Santa Fe Group (Spiegel and Baldwin, 1963).

The northern part of the San Luis Basin consists of three structural sub-elements: (1) the deep Baca Graben that runs along the eastern side of the valley; (2) a north-south-trending uplift in the middle of the valley called the Alamosa Horst that is now buried beneath the valley floor; and (3) the Monte Vista Graben along the western side of the valley. Montez Park is within the Monte Vista Graben, in which bedrock gradually becomes deeper from west to east, until reaching the Alamosa Horst where it rises up in the subsurface.

To the west, southwest, and northwest of Montez Park is the San Juan Volcanic Region (Figure 7), which generally coincides with the San Juan Mountains. The San Juan Volcanic Region formed during three distinctly different periods of volcanic activity (Lipman, 2000). The oldest period of volcanism started about 35 million years ago and consisted mostly of andesitic-composition lava flows, flow breccias, and volcanic mudflows from scattered stratovolcanoes. In the eastern part of the volcanic region these rocks are called the Conejos Formation. From about 30 to 26 million years ago voluminous sheets of silica-rich ash-flow tuff were violently blown from several different volcanic calderas shortly before or as the calderas collapsed. The rocks erupted from each caldera are assigned different names (e.g. Carpenter Ridge Tuff, Bachelor Mountain Tuff, Fish Canyon Tuff, Masonic Park Tuff, etc.). During the caldera phase of volcanic activity there was continued but sporadic eruptions from several andesitic-composition stratovolcanoes.

About 26 million years ago, coincident with the inception of the Rio Grande Rift, the volcanism shifted to chiefly basaltic and minor rhyolitic activity that erupted from relatively small volcanoes and fissures and flowed out across large areas. In the San Juan Mountains near the park these rocks are usually referred to as the Hinsdale Formation, although to the south and southeast they include other named formations. The volcanic rocks in the San Juan Volcanic Region generally dip eastward towards San Luis Valley, where they lie beneath the ground surface and are concealed by young, rift-related, unconsolidated surficial deposits.

Volcanic rocks of the of the San Juan Volcanic Region are important to this evaluation because they contain the economic metal deposits in the mining districts found in the San Juan Mountains, such as at Creede, Bonanza, Summitville, and Platoro. Igneous intrusions that fed the volcanoes were probably the source of the metals found in these mining districts.

Long before the volcanic activity initiated in the San Juan Volcanic Region, during the Cretaceous Period of the Mesozoic Era (age of dinosaurs), arms of the ocean transgressed (advanced) upon the interior of North America from the north and the south. This Western Interior Seaway


divided the North American continent into two relatively narrow landmasses (Figure 8). Most of Colorado was submerged beneath the ocean from about 100 million years ago to about 70 million years ago.

Organic-rich mud accumulated on the floor of the Western Interior Seaway, and sand was deposited along the beaches, deltas, and other marginal-marine environments. These sediments were subsequently buried by younger sediments that were deposited over them, causing the mud to lithify into (turn into) shale and the sand became sandstone. While these rocks were buried deeply in the subsurface and exposed to high temperatures and pressures, oil and natural gas were eventually formed by the anaerobic decay of organic material in marine shale. In western San Luis Valley, the primary source rocks for oil and gas are thought to be the Mancos Shale and Lewis Shale.

After oil and natural gas were formed, they tended to migrate through tiny pores in the surrounding rock. Some oil and natural gas migrated all the way to the surface and escaped, as at the oil seeps on Hope Creek and Quartz Creek in the San Juan Mountains (Gries, 1985). Other oil and natural gas deposits migrated until they were trapped under impermeable layers of rock or against faults or unconformities. These trapped deposits are where economically significant deposits of oil and natural gas are found today. Rocks in which the oil and gas are trapped are commonly called host or reservoir rocks. The primary host rocks in the western part of San Luis Valley reportedly are the Dakota Sandstone, Entrada Sandstone, and Junction Creek Sandstone, although an igneous sill within the Mancos Shale northwest of Del Norte also has produced oil, and biodegraded oil was found in a core drilled into an igneous stock in the Summer Coon volcano north of Del Norte (Gries, 1985).

Starting about 80-70 million years ago, near the end of the Cretaceous Period, ancient mountains began to rise up, forcing the Western Interior Seaway to move off the interior of the continent. The uplifting started as thin-skinned (shallow) deformation well west of Colorado during what is called the Sevier Orogeny. The uplifting gradually migrated eastward into Colorado and became deep-rooted and involved basement rock. This later period of mountain building is called the Laramide Orogeny. During the Laramide Orogeny, much of San Luis Valley was an uplifted mountain block called the San Luis Uplift (Tweto, 1980).

As the mountains rose, they were eroded. The sediment eroded from the Laramide San Luis Uplift is called the Blanco Basin Formation in the Monte Vista area. The Mesozoic rocks, which are both source and host rocks for oil and gas deposits, were eroded off the mountain uplifts, but they were oftentimes preserved in the structurally lowered basins. The Mesozoic rocks were preserved in the Raton Basin on the east side of the southern Sangre de Cristo Mountains and also in the San Juan Basin west and south of the San Juan Mountains. The Mesozoic rocks were also preserved in a concealed basin called the San Juan Sag, which is buried beneath the thick pile of volcanic rocks in the San Juan Volcanic Region west of the town of Del Norte (Gries, 1985; Brister and Chapin, 1994). The approximate position of the San Juan Sag relative to San Luis Valley and the San Juan Volcanic Region is shown in Figure 9.

The 1:250,000-scale map by Steven and others (1974) depicts the regional geology in the vicinity of Montez Park (Figure 10). Alluvial deposits consisting chiefly of sand, gravel, and silt are shown as underlying Montez Park on this regional map. These unconsolidated deposits blanket the entire valley floor and conceal the underlying bedrock. The closest bedrock outcrops to the park are in the foothills about four to five miles west, where small areas of the Carpenter Ridge Tuff and basalt flows of the Hinsdale Formation crop out. Field work by me has confirmed the information on the geologic map of Steven and others (1974).

The thickness of the unconsolidated deposits, depth to bedrock, and types of bedrock beneath Montez Park are important factors affecting the economic mineral potential of the property. A cross


section published by Brister and Gries (1994) summarizes much of what is known about the subsurface geology near the Park. A colorized version of the cross section is shown in Figure 11. The cross section is based upon geophysical seismic lines and lithologic logs from oil exploration drill holes.

In the cross section of Brister and Gries (1994) the sedimentary sand, gravel, and clay of the Santa Fe Group (includes Alamosa Formation) extends from the ground surface to about 2,000 feet deep; the underlying ash-flow tuffs lie at depths of about 2,000 feet to 3,600 feet; the Conejos Formation is about 3,600 to 7,800 feet deep; and the Blanco Basin Formation is from about 7,800 to 9,800 feet deep. The Blanco Basin Formation rests directly on the ancient Precambrian crystalline rocks. None of the Mesozoic rocks that are both the source and host rocks of oil and gas deposits are believed to exist in the subsurface beneath Montez Park.

Known Mineral Deposits in the Region: There are no permitted metal mines within many miles of the park (Colorado Division of Reclamation, Mining, and Safety, 2011). The large, well-known, metallic mining districts in the San Juan Mountains, such as at Summitville, Silverton, Bonanza, Creede, Lake City, and Platoro, are all within or adjacent to collapsed calderas. Much of the mineralization in these mining districts occurs in veins and lodes associated with faults in volcanic rocks. As shown in Figure 7, the nearest caldera is over 15 miles southwest of the park.

The Conejos Formation locally hosts relatively small metal deposits where those rocks are in close proximity to igneous intrusions. Examples include the small mining districts of Crystal Hill, Embargo Creek, and Cat Creek. Although these small mining districts are many miles from the park, they are the closest known metal deposits.

Gold and silver were recently extracted from the Conejos Formation at the Crystal Hill mine, which was in the foothills north of the town of La Garita. This mine is over 20 miles north of Montez Park. The mine was permitted in 1982 and shut down in 1995 (Tony Waldron, Colorado Division of Reclamation, Mining, and Safety, 2008, personal communication). The mineralization occurred in a steeply dipping intrusive breccia pipe within the Conejos Formation that was localized along the Beidell-Klondike fault zone (Pansze, 1987). The gold and silver were hosted in the matrix of the breccia, but the breccia clasts were barren. Ore grades averaged 0.035 to 0.038 ounces of gold per ton and 0.33 ounces of silver per ton, with reserves of about 1.5 million tons (Pansze, 1987).

Vanderwilt (1947) reported gold, silver, lead, and copper in the Embargo Creek area that was “presumably in veins”. These deposits also are in close proximity to Conejos-age intrusions (Steven and others, 1974). Patented and unpatented mining claims have been established in the Embargo Creek area, and small abandoned workings can be seen in this area, but no mines have been permitted in the area by the Colorado Division of Reclamation, Mining, and Safety (2011) since the permitting of metal mines began in Colorado. No metal production has been reported for these mines (Vanderwilt, 1947).

The nearest Conejos-age igneous intrusion is a very small igneous plug located over 8 miles to the west (Lipman, 1976). No metal mineralization has been reported at this intrusion. Numerous dikes and several stocks associated with the Summer Coon volcano are as near as about 12 miles northwest of the park (Lipman, 1976). Exploration for metals has occurred in this area, but no economically significant metal deposits have been discovered there.The nearest hard-rock mines to Montez Park with which I am familiar are north-northwest-trending calcite veins in the Fish Canyon Tuff that are located about 9 miles west of Montez Park (see Figure 12), and stone quarries, which are located in Section 10, T. 39 N., R. 6 E., also about 9 miles west of the park. At the stone quarries, blocks of Fish Canyon Tuff were produced for use as building stone.


The calcite veins in the Fish Canyon Tuff are associated with two mapped faults. The fault traces are a mile or less from the surface outcrop of a small plug of intermediate-composition intrusive rock (unit Tci in Figure 12). The calcite mines were very small operations. Most mines that I have seen worked veins along a west-dipping fault, although one worked a vein on an east-dipping fault that was parallel to and west of the east-dipping fault.

The mined calcite apparently was calcined into lime in nearby small kilns. Although no production history is available for these mines, they probably were last active at least 50 years ago and perhaps 100 or more years ago, at a time when proximity to market was a major economic factor. Today, lime is easily and cheaply produced by calcination of thick and widespread limestone beds, and the transportation of lime over long distances is relatively inexpensive. Although the economic potential of these calcite veins is very low, they may have been deposited in a hydrothermal system that could have precipitated metals elsewhere along the vein, at as yet undiscovered locations.

I visited the northerly four calcite mines a couple of decades ago, but was recently unsuccessful in gaining access onto these privately owned lands. I was able to examine the two southerly mines in 2009. Figure 13 is a photograph of the vein exposed in the small mine pit that is located on the west-dipping fault. Here the vein has a strike azimuth of 340 to 345o, a dip of 75 to 85o east, and a width of about 6 to 9 feet. No evidence of metallic mineralization was observed in the vein.

Sand and gravel has been mined in many areas of San Luis Valley, including the Monte Vista area. It is the only mineral resource that has been recently mined or is actively mined in the vicinity of Montez Park (Colorado Division of Reclamation, Mining, and Safety, 2011).

Several wells have been drilled in San Luis Valley to evaluate the potential for oil and gas (Colorado Oil and Gas Conservation Commission, 2011), but none have led to the discovery of an economic oil or gas resource. The most promising results were obtained in the San Juan Sag (Gries, 1985; Brister and Chapin, 1994). The eastern boundary of the San Juan Sag is not precisely constrained, but drilling in the San Francisco Creek area south of Del Norte indicates the boundary of the sag is over 8 miles west of the park.

Several of the wells drilled in the San Juan Sag encountered shows of oil and gas, and one well, the Kirby Petroleum Jynnifer #1 well, reportedly produced 30 barrels of oil per day (Gries, 1985, 1989). The interest in the San Juan sag was stimulated by the discovery of Mesozoic rocks beneath the volcanic cover of the San Juan volcanic field and oil seeps found at the surface. In 2008 oil and gas leases on federal lands in the San Juan Sag were proposed, but subsequently deferred for additional analysis. Another oil and gas prospect is in the eastern part of San Luis Valley, over 25 miles northeast of Monte Vista (Watkins, 1996; Morel and Watkins, 1997). This play by Lexam Energy Exploration is on the Baca National Wildlife Refuge on the northwest side of the Great Sand Dunes National Park and Preserve. Shows of oil were encountered in several shallow mineral exploration holes and in two deeper oil tests (Lexam Energy Explorations Baca no. 1 and 2 wells) that were previously drilled in the area. No production has occurred in this play. Two proposed 14,000-feet-deep test wells have been permitted but not yet drilled (Colorado Oil and Gas Conservation Commission, 2011). Again, the presence of Mesozoic rocks in the subsurface and in outcrop was a key element of this exploration effort.

Biogenic gas has been produced as a by-product of water wells in the east-central part of the San Luis Valley. The biogenic gas is both sourced by and hosted in the Alamosa Formation, which is on the order of 1,000 feet thick in that part of the valley. The biogenic gas from the Alamosa Formation has been utilized historically only for on-site purposes such as cooking. No commercial


production of biogenic gas is known to have occurred. Siebenthal (1910) provided perhaps the most comprehensive published information on these biogenic gases. A map by Siebenthal (1910) depicts the “limit of the gas field” near the time of highest historical use of the biogenic gases, and a map by Gries and Brister (1989) shows locations of water wells that produced biogenic gas. These maps indicate that the limit of the “gas field” and the gas-producing water wells are over 15 miles east of the park. Also, the Alamosa Formation is very thin beneath the park relative to its thickness in the biogenic gas area.

Potential for Economic Mineral Resources at Montez Park: Section 12-17-140 of the City of Monte Vista Zoning Code states: “Extractive industries and salvage yards shall be located a minimum of six hundred sixty (660) feet from any residential district or school.” Montez Park is within 660 feet of both a school and a residential district, which eliminates the potential for mining or oil and gas production on the park property.

However, zoning codes can be modified or eliminated in the future, or contested in court. Therefore, the following discussion of the potential for economic mineral resources of the park is warranted.

Sand and gravel is the only significant mineral resource that potentially may exist beneath Montez Park. Available information indicates the potential for economic deposits of all other minerals, including oil and gas, beneath the park is very low.

Several factors indicate the potential for economic metal deposits on and beneath the park is very low. These factors include: (1) thick deposits of unconsolidated sediments and sedimentary rocks conceal the volcanic bedrock beneath Montez Park; this discourages exploration for metal deposits in the bedrock; (2) placer deposits are not known to exist in the unconsolidated deposits along the Rio Grande in the vicinity of the park; (3) nearly all metal mining in the San Juan Mountains has been in or adjacent to calderas, and the closest caldera to the park is over 15 miles away; (4) minor metal mineralization is associated with some of the Conejos-age intermediate-composition intrusions in the San Juan Mountains, but the nearest intrusion crops out over 8 miles west of the park, and no known significant mineralization is associated with it; and (5) calcite was produced from the closest known mined veins to the park (9 miles to the west), but this type of calcite mineralization is no longer economically significant, and metallic mineralization apparently does not occur in these veins.

Hard, indurated bedrock suitable for dimension stone or other industrial uses does not crop out at the park, and it is found only about 2,000 feet below the park. There is no potential for stone quarrying on the property.

The potential for economic deposits of oil or gas at Montez Park is very low. Available information indicates the Mesozoic-age source and host rocks associated with the known or potential deposits in the region do not exist beneath the park. The nearest area known to potentially have economic oil or gas deposits is within the San Juan Sag, whose margin is about 8 miles west of the park. The park also is over 25 miles from the potential gas play proposed by Lexam Energy Exploration at the Baca Ranch, which also involves Mesozoic source and host rocks. The biogenic gas area is over 15 miles east of the park, and the source and reservoir rock for the biogenic gas (Alamosa Formation) is thin and unlikely to generate or host economic biogenic gas in the vicinity of the park. Hence, Montez Park is not only many miles from any known potential oil and gas area, but there probably are not any significant source rocks beneath the park.


Keller and Wray (2001) conducted reconnaissance investigations of the mineral and mineral fuel potential of state mineral lands administered by the Colorado State Land Board in Rio Grande, Alamosa, and Conejos Counties. Tract 105-12 of Keller and Wray includes parcels of state-owned minerals that are adjacent to the west and northwest parts of the city of Monte Vista, less than 1 mile from Montez Park. These parcels are geologically similar to Montez Park in that relatively thick sequences of alluvial sediments overlie the same sedimentary and volcanic rocks that project beneath the park. Keller and Wray (2001) stated that these state mineral lands were “…not prospective for metallic mineral resources”. They also stated that there was little or no potential for oil and gas resources on these tracts “due to the lack of most of the essential elements for hydrocarbon accumulation”. Keller and Wray used a numeric scale to rate the mineral potential of the tracts with state-owned mineral rights. On a scale of 0 to 5, with 0 indicating little to no potential and 5 indicating proven mineral reserves, the tract was rated at 0.1 for both metallic mineral resources and oil and gas resources.

Keller and Wray (2001) recognized that the sand and gravel resources of the nearby state-owned mineral estates were significant. They assigned a commodity rating of 4 (an identified resource) to the industrial minerals/construction minerals on the state property. I conclude that a similar identified sand and gravel resource probably exists at the park, although subsurface investigations were not conducted to confirm this interpretation.

However, there are several factors that minimize the potential for or preclude future mining of sand and gravel at the park:

(1) The park is only 70 feet wide. This narrow width probably is too restrictive to allow for a commercial sand and gravel operation on the property.

(2) The narrow park is also divided into three tracts by city streets (Franklin and Lyell streets), which further restricts the operational area available to a commercial sand and gravel operation.

(3) A commercial sand and gravel operation also would have to overcome the current zoning codes of the city, which precludes extractive mineral activities at the location of the park.

(4) The groundwater table probably is shallow at Montez Park. A sand and gravel pit likely would expose groundwater to evaporation, which would necessitate the acquisition of a court-approved water augmentation plan and probably the purchase of surface water rights. Costs related to the augmentation plan would probably make sand and gravel mining uneconomic.

and (5) Montez Park was originally part of tracts of land that were patented February 5, 1885. The SE ¼ of section 31 was homesteaded by Hiram H. Marsh (BLM serial number COCOAA033681), and the SW ¼ of section 31 was homesteaded by Henry Taylor (BLM serial number COCOAA033684) (BLM, 2011). The federal government did not reserve any minerals, including sand and gravel, when these lands were patented. Colorado courts have typically determined that when minerals rights are privately owned, the rights to the sand and gravel belong to the surface owner unless it has some unusual quality like being a placer deposit or the sand and gravel were specifically reserved by a seller when the property was sold in the past. This aspect is described in Colorado Coalition of Land Trusts (2008). This publication states on pages 18 and 19 “Most state courts that considered this same issue in the context of grants or reservations by private parties have concluded that ordinary sand and gravel is not conveyed to or reserved by the mineral estate owner unless the parties have done something to express clearly their intent that those materials are indeed to be included within the mineral estate”. As such, the city of Monte Vista may well be the owner of the sand and gravel after it purchases this land, and thus be able to restrict future mining of sand and gravel on the property. No attempt was made to thoroughly research all deeds relating to this property to


ascertain whether the sand and gravel has been reserved during prior land transfers because the four other above described factors probably are by themselves sufficient to assess the likelihood of future sand and gravel development at Montez Park.

Conclusions: On the basis of available information and current economic conditions, as well as the City of Monte Vista Zoning Codes, I conclude that the potential for mining or the development of oil and gas resources at Montez Park is so remote as to be negligible.

Sincerely,

Robert M. Kirkham AIPG certified professional geologist #4782



SELECTED REFERENCES

BLM, 2005, Del Norte, Colorado 1:100,000-scale map showing surface and mineral management status: U.S. Bureau of Land Management, scale 1:100,000.

BLM, 2011, General Land Office Records: U.S. Department of Interior, Bureau of Land Management website http://www.glorecords.blm.gov/results/default.aspx?searchCriteria=type=map|st=CO|twp_nr=39|twp_dir=N|rng_nr=8|rng_dir=E|m=23|sec=31.

Brister, B.S., and Chapin, C.E., 1994, Sedimentation and tectonics of the Laramide San Juan Sag, southwestern Colorado: The Mountain Geologist, v. 31, p. 2-18.

Brister, B.S., and Gries, R.R., 1994, Tertiary stratigraphy and tectonic development of the Alamosa Basin (northern San Luis Basin), Rio Grande Rift, south-central Colorado, in Keller, G.R., and Cather, S.M., eds., Basins of the Rio Grande Rift; Structure, stratigraphy, and tectonic setting: Geological Society of America Special Paper 291, p. 39-58.

Colorado Coalition of Land Trusts, 2008, Mineral development and land conservation: Denver, Colorado Coalition of Land Trusts, 130 p.

Colorado Division of Reclamation Mining & Safety, 2011, On-line mine database and GIS maps: available on the internet at http://mining.state.co.us

Colorado Division of Water Resources, 2011, Digital water well information: available digitally at the State Engineer’s office at 1313 Sherman Street, Room 818, Denver, CO, and at any CDWR division office.

Colorado Oil and Gas Conservation Commission, 2011, On-line oil and gas well information: available on the internet at http://oil-gas.state.co.us

Gries, R.R., 1985, San Juan Sag: Cretaceous rocks in a volcanic-covered basin, south central Colorado: The Mountain Geologist, v. 22, no. 4, p. 167-179.

Gries, R.R., 1989, San Juan Sag; Oil and gas exploration in a newly discovered basin beneath the San Juan volcanic field, in Lorenz, J.C., and Lucas, S.G., eds., Energy frontiers in the Rockies: Albuquerque Geological Society, New Mexico, p. 69-78.

Gries, R.R., and Brister, B.S., 1989, New interpretations of seismic lines in the San Luis Valley, south-central Colorado, in Harmon, E.J., ed., Water in the valley: Colorado Ground-Water Association, 8th annual field trip, p. 241-254.

Jackson, J. A., 1997, Glossary of geology: American Geological Institute, Alexandria, Virginia, 769 p. Keller, J.W., and Wray, L.L., 2001, Evaluation of mineral and mineral fuel potential of Alamosa, Conejos, and

Rio Grande Counties state mineral lands administered by the Colorado State Land Board: Colorado Geological Survey, Open-File Report 00-15, CD-ROM.

Lipman, P.W., 1976, Geologic map of the Del Norte area, eastern San Juan Mountains, Colorado: U.S. Geological Survey Miscellaneous Investigations Series I-952, scale 1:48,000.

Lipman, P.W., 2000, Central San Juan caldera cluster: Regional volcanic framework, in Bethke, P.M., and Hay, R.L., eds., Ancient Lake Creede: Its volcano-tectonic setting, history of sedimentation, and relation to mineralization in the Creede Mining District: Geological Society of America Special Paper 346, P. 9-58.

Lipman, P.W., 2006, Geologic map of the central San Juan caldera cluster, southwestern Colorado: U.S. Geological Survey Geologic Investigations Series I-2799, scale 1:50,000.

Lipman, P.W., and McIntosh, W.C., 2006, Field trip to northeastern San Juan Mountains; North Pass & Cochetopa calderas: Geological Society of America, Rocky Mountain Section, May 15-16,2006, 19 p.

Morel, J., and Watkins, T., 1997, More data point to potential in S. Colorado sub-basin: Oil & Gas Journal, v. 95, no. 35, p. 78-80.

http://mining.state.co.us/

Pansze, A.J., 1987, Geologic sketch of the Crystal Hill breccia pipe, Saguache County, Colorado, in Gee, W.R., and Thompson, T.B., eds., Gold mineralization of Colorado’s Rio Grande Rift: Denver Region Exploration Geologists Society, September 1987 field trip guidebook, p. 23-25.

Siebenthal, C.E., 1910, Geology and water resources of the San Luis Valley, Colorado: U.S. Geological Survey Water-Supply Paper 240, 128 p.

Spiegel, Z., and Baldwin, B. 1963, Geology and water resources of the Santa Fe area, New Mexico: U.S. Geological Survey Water-Supply Paper 1525. 258 p.

Steven, T.A., Lipman, P.W., Hail, W.J., Jr., Barker, F., and Luedke, R.G., 1974, Geologic map of the Durango quadrangle, southwestern Colorado: U.S. Geological Survey Miscellaneous Investigations Series I-764, scale 1:250,000.

Tweto, O., 1980, Summary of Laramide Orogeny in Colorado, in Kent, H.C., and Porter, K.W., eds., Colorado Geology: Denver, Colorado, Rocky Mountain Association of Geologists, 1980 symposium, p. 129-134.

Vanderwilt, J.W., 1947, Mineral resources of Colorado: State of Colorado, Mineral Resources Board, 547 p. Watkins, T.A., 1996, Geology of the northeastern San Luis Basin, Saguache County, Colorado, in Thompson,

R.A., Hudson, M.R., and Pillmore, C.L., eds., Geologic excursions to the Rocky Mountain and beyond: Colorado Geological Survey, Special Publication 44, CD-ROM.

Figure 1. Regional location map. The property is within the City of Monte Vista in south-central Colorado. (base map from National Geographic TOPO! software)


Figure 2. Location map of Montez Park, which is shown by the narrow yellow polygon (base map from National Geographic TOPO! software, which uses the U.S. Geological Survey’s Monte Vista 7.5-minute quadrangle maps; contour interval = 10 feet)


Figure 3. Photograph of the central section of Montez Park looking east-south. Cars in left side of photo are on highway 160/285; tracks of the San Luis Rio Grande Railroad are on the right side of the park; and Franklin Street is in the foreground. Note the absence of bedrock outcrops on and near the property.

Figure 4. Map showing the proximity of tracts with Federal minerals to Montez Park. Small, narrow, yellow polygon in Monte Vista indicates location of Montez Park. Closely spaced vertical lines on left side of map denote tracts with Federal mineral rights; areas without the closely spaced lines indicate private or state-owned mineral rights. Surface ownership is indicated by colors: yellow-brown = Federal land administered by the Bureau of Land Management; light blue = State of Colorado Trust Lands administered by the State Land Board; and white = private land.


Figure 5. Map showing State-owned mineral rights near Montez Park (modified from Keller and Wray, 2001).

Figure 6. Map of the Rio Grande Rift in the United States. Rift continues south into Mexico. Structural basins within the rift are shown by the yellow, green, brown, and purple colors. Image courtesy of U.S.G.S.


Figure 7. Regional relationship between Montez Park, the present surface extent of the San Juan Volcanic Region (in blue), and the calderas (in light red) within the volcanic region. The names of the calderas are shown. The number in parentheses below the name indicates the age of the caldera in millions of years.


Figure 8. Paleogeographic map during the Late Cretaceous (~90 million years ago). Brown areas indicate landmasses at that time; dark blue areas were deep ocean areas (up to miles deep); and pale blue areas denote shallow ocean areas (less than a few 1000 feet deep).

Figure 9. Regional map showing location of Montez Park relative to the San Juan Sag (after Gries, 1985).


Figure 10. Regional geologic map (modified from Steven and others, 1974). Montez Park and adjacent lands are underlain by the pale yellow unit labeled Qa, which consists of Quaternary alluvial sediments deposited by the Rio Grande. Unit QTg consists of poorly lithified sedimentary rocks that are late Tertiary to Quaternary in age and overlie volcanic rocks. From youngest to oldest, the volcanic formations include the Miocene-age Hinsdale Formation (unit Thb on map); the Oligocene-age Bachelor Mountain and Carpenter Ridge ash-flow tuffs (unit Tbc), Fish Canyon ash-flow tuff (unit Tfg), and Masonic Park ash-flow tuff (unit Tmp); and the Eocene- to Oligocene-age lava flows and breccias in near-source vent facies of the Conejos Formation (unit Tev) and sedimentary rocks in the volcaniclastic facies of the Conejos Formation (unit Ten).


Figure 11. Interpretive east-west cross section across the San Luis Basin (modified from Brister and Gries, 1994). Line of section is about 3 ½ miles north of Montez Park, which projected to the cross section would be located immediately east (right) of the Tennessee Gas well.


Figure 12. Detailed geologic map of the area where historic calcite mining has occurred in sections 21, 28, and 33, T. 39 N., R. 6 E. Area is located in the foothills about 9 miles west of Montez Park. See Figure 10 for the location of this detailed map.

Figure 13. Photograph of the calcite vein in a mine pit at UTM coordinates 383725 m N, 4160620 m E, approximately 9 miles west of the easement. Hammer rests against fine-grained, more-or-less massive calcite. Nearly vertical layers to the left of the hammer are undulating, banded, coarsely crystalline calcite. Smooth surface to left of the banded calcite is the footwall of the vein, which consists of a thin layer of calcite against in-place ash-flow tuff bedrock.



Appendix A. Legal description of Montez Park. (from survey plat by Reynolds Engineering Company, 21626 C.R. AA.5, Alamosa, CO 81101; phone # 719-274-3218; plat dated February, 2011) LEGAL DESCRIPTION A tract of land being a part of the right-of-way for the Denver and Rio Grande Western Railroad situated within Section 31, Township 39 North, Range 8 East, of the New Mexico Principal Meridian and being within the city limits of Monte Vista, Rio Grande County, Colorado and more particularly described by metes and bounds as follows to-wit: Considering the centerline of the existing railroad tracks for the Denver and Rio Grande Western Railroad as bearing N 62o30’30” W and with all bearings contained herein relative thereto: Commencing at the southeast corner of said Section 31: Thence N 55o43’29” W a distance of 1997.30 feet to a point that is 30.00 feet northeast of the centerline of the railroad right-of-way, being the true point of beginning; thence N 62o30’30” W along a line that is 30.00 feet northeast of and parallel with the centerline of the railroad right-of-way a distance of 1385.00 feet to the intersection of the south right-of-way line for U.S. Highway 160; then along the south right-of-way line of U.S. Highway 160 for the following three (3) courses: Thence S 89o42’49” E a distance of 32.13 feet to a point of curve: thence 237.41 feet along the arc of a curve to the right having a central angle of 27o12’19”, a radius of 500.00 feet and a chord which bears S 76o06’39” E a distance of 235.19 feet to a point of tangency: thence S 62o30’30” E a distance of 1127.84; thence S 27o29’30” W a distance of 70.00 feet to the true point of beginning, containing 2.090 acres more or less.


Appendix B. Statement of Qualifications.

STATEMENT OF QUALIFICATIONS for

Robert M. Kirkham

Mr. Kirkham is Certified Professional Geologist #4782 by the American Institute of Professional Geologists and is Registered Professional Geologist #1242 by the State of Wyoming Board of Registration for Professional Geologists. He meets the qualifications of a Professional Geologist as defined by Colorado Revised Statute 34-1-201. Mr. Kirkham received a B.S. degree in Geology in 1973 from Western Illinois University and a M.S. degree in Geology in 1976 from the Mackay School of Mines, University of Nevada at Reno. He has over 30 years of experience working as a professional geologist doing geologic mapping, engineering geology and active fault evaluations, environmental geology, mine reclamation, and mineral assessments. During much of his career he worked as a geologist for the Colorado Geological Survey and as a reclamation specialist for the Colorado Mined Land Reclamation Division (currently called the Colorado Division of Reclamation, Mining, and Safety). He retired from the State of Colorado in 2003 and began working as a consultant. He presently is the owner of a sole proprietorship called GeoLogical Solutions, based in Alamosa, Colorado. Mr. Kirkham has published about 120 reports and abstracts, including about forty geologic maps of 1:24,000-scale quadrangles in Colorado and Wyoming. He currently belongs to seven professional geological organizations, is the Secretary of the Colorado Field Institute, and was the co-chair of the Colorado Earthquake Hazard Mitigation Council for the past ten years.

Documents

ROBERT M. KIRKHAM, GEOLOGIST, P.G., C.P.G.siterepository.s3.amazonaws.com/00175201202171011207942.pdf · San Juan Volcanic Region west of the town of Del Norte (Gries, 1985; Brister