Rock Springs Uplift - Leucite Hills
map
WGS
Eocene Lake Gosiute GSA


Dahy, J. P., 1991, Geology and igneous rocks of the Yogo sapphire deposit, Little Belt Mountains in Guidebook of the Central Montana alkalic province, D W Baker and R B Berg, eds; Montana Bureau of Mines and Geology, Special Publication number 100, pp 45-54


hatr

Magnetic study of metamorphosed sedimentary rocks of the Hatrurim formation, Israel

mindat

mineralogy, S. Gross, 1977, Geol. Surv. Israel, Bull

buy 'em

BM r edit

Sierrita edit

View of Sierrita Mountains and copper mines from Corona de Tucson in the Santa Rita foothills some 25 miles to the east.

The Sierrita Mountains are a range in Pima County, Arizona lying some twenty to thirthy miles south-southwest of Tucson The range is a broad oval physiographic dome some 20 to 30 miles across. The central peaks, Keystone Peak (6188 ft) and Samaniego Peak (5991 ft) are on a N-S trending five mile ridge area above 5000 feet. This central ridge area is surrounded by a broad gently sloping pediment reaching an elevation of around 2500 feet on the northeast at the Santa Cruz valley in south Tucson. The arroyos around the range form a classic radial drainage pattern.

The Santa Cruz Valley bounds the range to the east separating it from the Santa Rita Mountains. The west margin of the range is the broad Altar Valley. To the southwest the Sierritas merge with the Cerro Colorado Mountains and the Penitas Hills. The Tumacacori Mountains of Santa Cruz County, Arizona lie to the southeast.

Geology edit

Mining edit

File:Pima Co. Copper mines.jpg Satellite view of the copper mines on the east flank of the range January 14, 2010.


31°57′N 111°8′W / 31.950°N 111.133°W / 31.950; -111.133


References edit

Tumacacori edit

The Tumacacori Mountains are a generally north-south range in western Santa Cruz County, Arizona although the western foothills extend into Pima County. The southern end of the range extends to the west to north of Ruby and the associated mining area. In the south the range merges with the Atascosa Mountains accross Peck Canyon ant Hells Gate gorge (elevation 3600 ft.) Ruby, Arizona, 7.5 minute Quadrangle, USGS, 2004 The Sierrita Mountains lie to the north, the Cerro Colorado Mountains and the Las Guijas Mountains are to the west and the Santa Rita and smaller Cayetano Mountains lie to the east across the Santa Cruz Valley. Sells, Arizona, 30x60 minute Quad, USGS, 1994 Atascosa, Arizona-Sonora, 30x60 minute Quad, USGS, 1994

Interstate 19 and the communities of Arivaca Junction, Tubac, and Tumacacori are to the east of the range and Arivaca Road runs to the north and west with Arivaca lying west of the range. The Ruby-Nogales Road (Arizona Route 289) runs past the southwest side of the range and connects with Arivaca.

  • Peaks include:
  • Bartollo 5381 31 30.58 111 12.22
  • Murphy 5331 31 31.11 111 09.86
  • Dicks 5391 31 31.58 111 09.73
  • Tumac 5635 31 33.03 111 06.99
  • Tumacacori 5177 31 34.26 111 05.08
  • Sardina 5616 31 35.44 111 07.35
  • Tubac 4933 31 39.02 111 07.42
  • Unnamed (highest) 5736 31 33.495 111 06.776


Yogo analysis edit

Analysis of Voynick references - article wording compared to book wording.

  • ref 5 pp. xii, 116: p xxi is a map, as is 116
  • ref 8 p 116 map, last usage re Jake Hoover not supported by p 116, but is on p. 15 w/ no prob
  • ref 11 p 10 first use ok, 2nd ok, 3rd ok but on p. 11
  • ref 12 p ix-xi used once rather close p'raps - modified
  • ref 15 p 6-8: 2nd use ok, 1st use not supported directly, implied & rather obvious
  • ref 17 p 31-32: first two uses ok - third use not supported on those pages , not fixed replaced w ref 60 ref name=voynickflood
  • ref 18 p 62-63: ok
  • ref 23 p 193: first ok, 2nd and 3rd - not on that page, not fixed replace 2nd w/ ref name=voynickothers previously ref #36 Removed 3rd usage as not supported.
  • ref 24 p vii: "many gem experts[23][24] consider Yogos to be among the world's finest sapphires."
    • book says "some gem experts consider the world's finest sapphire." too close?
  • ref 36 p 19-21: ok
  • ref 37 p 16-19: ok
  • ref 39 p 76-78: ok
  • ref 41 p viii & 2-3 "While on a weight-for-weight basis sapphires are worth more than gold" and "whereas gold was easier to identify and merely required digging and selling."
    • book p. viii: "While far more valuable on a weight-for-weight basis, were unlike gold" and "Gold required merely digging and selling." too close - Edit comment added
  • ref 42 pp. 3–4, 29–31: ok, just uses p 31
  • ref 43 pp. 31, 29–31: just p. 31 a quote from the book, quoting Kunz: "the finest precious gemstones ever found in the United States". It is a quote of a quote. Refs 42 & 43 only seem to use p 31 and are redundant
  • ref 45 pp. 32–35: no problem noted
  • ref 46 pp. 109–112: no probs.
  • ref 47 pp. 74–76: no probs
  • ref 48 p 21: seems ok, most of this must be from ref 49
  • ref 52 pp. 22–30: ok the relevant page is 23
  • ref 57 pp. 36–42: first ok, 2nd and 3rd not in that page range
  • ref 58 pp. 71–73: ok...? re: focused
  • ref 59 pp. 80–81: seems ok
  • ref 60 pp. 102–109: ok
  • ref 61 pp. 117–122: ok but didn't see the $29,000 figure in the book - removed the "spent $29,000 of" as failed verification (Feb 05)

18:23, 2 February 2012 (UTC)

  • ref 62 pp. 57–64: ok ref for 1st part of paragraph
  • ref 63 pp. 75–77, 95–96: pp95-96 support last two sentences (ok), pp 75-77 1909 bankruptcy, ok
  • ref 64 pp. 122–130: ok
  • ref 65 pp. 125–134: mostly ok, "The final price was $65,000 and various stock considerations." vs (book p 131) "The final agreement was $65,000 cash and various stock considerations ..." is close
  • ref 66 pp. 134–135: ok
  • ref 67 pp. 136–138: ok
  • ref 68 pp. 138–144: most ok, "... first serious effort to mine Yogo Gulch since the early days of the English Mine." vs book p 142: "... first truly serious mining since the days of the English Mine." close...
  • ref 69 pp. 144–150: ok
  • ref 70 pp. 151–154, 158–164: ok
  • ref 71 pp. 165–181: lots of material covered ... seems ok
  • ref 72 pp. 181–185: ok except 1985 Pa movement is on p 187 (fixed Feb 05)

02:33, 4 February 2012 (UTC)

  • ref 73 pp. 185–191: seems ok
  • ref 74 pp. 193–195: 280 ft shaft depth no suppoerted in that page range, p 197 says 200 ft in 1994. Note new info re: maar & diatreme on p 196 - geology section stuff ... kinda like a diamond pipe, thinkin
  • ref 75 pp. 196–198: 11 carat rough is on p 197 quoting a news report. "...extension of the main dike" don't see that and the discussion on that section adds complexity - interesting stuff there
  • ref 76 pp. 198–201: ok except phrase, "...what is known as the Eastern Flats Dike" worded identical to book
  • ref 77 pp. 201–207: ok, the number heavy part is necessarily similar perhaps
  • ref 84 pp. 62–64: should be pp 61-62 (fixed Feb 05)
  • ref 86 pp. 57–58: ok - wasn't this "silver medal" bit mentioned earlier?
  • ref 87 p. 93: ok
  • ref 88 pp. 114–115, 204: broach illustration in plates bet. 114, The most elaborate piece of jewelry ever made with Yogos is almost a direct copy of the image caption. p 204 repeats thi with "magnificent" instead of "elaborate". Reminds me of image caption problems discussed on the talk page earlier
  • ref 90 p. 163: 1st use not supported, 2nd use also not supported except maybe by WP:SYN (removed as failed verification on Feb 05)

I've examined all refs and found a few problems - will return to do some fixin' later. Vsmith (talk) 16:14, 5 February 2012 (UTC)

Applied some fixes (page # changes etc) and removed a couple of refs as failed verification. Note the ref numbers above were as of 16:14, 5 Feb, due to the nature of the ref system the numbers will change - so refer to that "edition" if it gets confusing, sorry 'bout that. Vsmith (talk) 01:15, 6 February 2012 (UTC)


Comments: The bit about "many experts" I think could be verified by adding a couple more sources. Or we could say "Voynich says "some". If there is stuff that needs a fix, put a hidden text tag in that says "rephrase" or something and I'll take a whack at it. Montanabw(talk) 19:06, 2 February 2012 (UTC)

Storage edit

WP:ANI 18:42, 2 August 2012

Work in progress edit

The following is a machine translation of WP:de http://de.wikipedia.org/wiki/Navajo_Volcanic_Field and cleanup is in progress 11/13/12

NVF tr WP:de edit

File:Map of the Navajo Volcanic Fields.jpg The Navajo Volcanic Field, in the Navajo language tsézhiin 'íí' Ahi ("black prominent rock"), is an approximately 30,000 square-mile volcanic field[1] in the Four Corners designated border area of the four U.S. states of Utah, Colorado, Arizona and New Mexico. It is located on the Colorado Plateau at 1800 meters high and was built in the Oligocene and Lower Miocene before about 28 to 19 million years ago. The volcanic manifestations consist of more than 80 diatremes and tuff breccias and smaller intrusions, dikes, sills, lava flows, maars and volcanic necks, exposed by the erosion of the surrounding relatively soft sandstone.

The geological significance of the Navajo Volcanic Field lies in the fact that the volcanic phenomena occurred relatively shortly after the end of the Laramide orogeny. They thus provide an insight into the mantle beneath the Colorado Plateau, a geologically relatively peaceful region.[2] In fact, numerous magma flows swept rocks from the mantle and they are now embedded in the exposed rocks. Such objects are called xenoliths known and often consist of spinel and rare garnet peridotite and eclogite.[1]

Geographical overview edit

(image of Shiprock) Shiprock, probably the best known example of a volcanic necks from the Navajo Volcanic Field)

The Navajo Volcanic Field has a roughly arcuate structure of the north-west to south of about 300 km long and 100 km wide, with a recessed area in the northeast near the Mesa Verde plateau. The northwestern boundary of the volcanic field forms the eastern edge of the Monument Upwarp, its northern section extends into the Paradox Basin, near the center stand the Carrizo Mountains and its southern part includes the Defiance Uplift and the Chuska Mountains. The east part of the field is in the San Juan Basin.

The pre-volcanic geological environment of the Navajo Volcanic Field consists mainly of Mesozoic sandstones with an age from 251 to 65 million years ago (mya), such as the Chinle Formation, in the area of Chuska Mountains as well as younger rocks from the Paleogene, with an age of 65 to 28 mya as the Chuska Sandstone.

The volcanic phenomena are concentrated along the monoclines designated exterior steps, as part of the Laramide orogeny caused some 80 to 40 million years ago. The invading of the necks of monocline aligned magma bodies was facilitated by the existing fracture zones associated with the monocline structures.[3]

Volcanism edit

(Image of Agathla Peak)
Neck of Agathla peak, also called El Capitan

The volcanoes of the Navajo Volcanic Field are predominantly maar-diatreme volcanoes. They were phreatomagmatic eruptions produced when magma encountered groundwater. This triggered steam explosions with a particularly high resulting eruption energy.[4] Under the multiple outbreaks the diatreme vent through to the surface and a flat maar crater is blasted out to a tuff ring of pyroclastic material. With the gradual depletion of the groundwater supply the explosions migrate further into the depths, leaving a funnel-shaped chimney, filled with breccias of solidified magma and country rock fragments.[5] After the explosive activity can magma ascending to Schlotbrekzien and as lava fill the maar crater. Occasionally, lava flows also overflows and leaves the crater. In the final stage, it is then often a Nachstürzen the top chimney area.

Eight exceptions in the field are serpentinized ultramafic microbreccias (acronym: SUM) existing chimneys, seven of which are in close proximity to the monoclines. The emergence of these microbreccias explained by the fact that gas-rich magma under relatively low temperatures encountered water-bearing rock causing the magma to cool very rapidly and fracture forming fine fragments.[6]

Due to its high elevation the erosion in the Colorado plateau is particularly strong. Many volcanic centers of the Navajo Volcanic Field have been uncovered by erosion, and project beyond the current ground level. The prime example is Shiprock - a neck of tuff breccia, which roughly represents the central portion of a diatreme. At its peak just Nachsturzeffekte is present as typical of the upper portion of a diatreme. Another familiar example is the Agathla Peak.

Rock composition edit

The typical volcanic rocks in the Navajo Volcanic Field are mostly dikes. The end of the eruption caused lava flows usually consist of trachybasalt. These consist of the same material as the dikes, but have a different structure, because they occur at the surface, which is at atmospheric pressure; harden as dikes in the conduit below the surface and under pressure. In addition to the dikes with eight chimneys are called serpentinized ultramafic microbreccia filled chimneys. They were initially considered to be kimberlites[6] to the new, descriptive name has been established.[7]

Also occurring in the Navajo Volcanic Field sporadically alongside the mine tablets are some very rare rock types, such as sodium-containing lamprophyres (monchiquite) Olivinmelilithit and Katungit.[5]

The dikes are lamprophyres, due to their high magnesium and iron content than mafic be classified. They consist of about 50 weight percent of SiO2 in combination with a very high K2O content from an average of 6%. Few dikes have higher SiO2 contents of up to 60% SiO2 and are classified as felsic.[7] The higher SiO2 -shares can be achieved by fractional crystallization explain in later stages of ascent. The temperature of the dike magma during the eruption is estimated to be 1000 ± 75 °C or after another melt sample to between 1000 and 1200 °C.[5]

The rocks of the Navajo volcanic field show that the mantle beneath the Colorado Plateau has strong similarities with oceanic crust. It was there, so presumably in the Precambrian subduction of a submarine tectonic plate under a continental plate occurred,[1] was to explain the Laramide orogeny related to subduction of the Farallon plate fits. However, the rocks are in their chemical composition is not fully with prevailing rock in the mantle peridotite is identical, but there is a lack of political groups Peridotits whereby potassium, as well as the iron and magnesium content relative increase.

For the origin of the magma and the declaration of its petrology different approaches are discussed.[5] In particular, it is proposed that the mantle-peridotite earlier from a potassium metasomatism was gone before he aufschmolz partially and ascended along fault lines in the earth's crust; is also possible that the chemistry of the volcanic field, missing ingredients were separated in a previous partial melting. Alternatively it is believed that the high iron and magnesium components outside of your actual mantle rocks themselves are, but are geologically much earlier accumulated by melt process and intrusive rocks in the mantle reached, which would later melt to magma. Finally comes an unspecified fractional crystallization of an existing ultramafic magma into consideration.

It follows that the eight SUM diatremes owe their origin to a magma with very high gas content, the few felsic mine tablets date from the uppermost part of melting, the majority of mafic mine tablets from deeper layers.[7] The analysis of rock distribution within the diatremes suggests that the Mohorovičić discontinuity is below the Colorado Plateau at about 43 km depth.[8]

History and ethno geology edit

In the environment of the Navajo Volcanic Fields are a large number of spectacular signs of settlement of prehistoric Southwest, especially the Anasazi cultures and their pueblos. With Chaco Culture National Historical Park, Canyon de Chelly National Monument , the Mesa Verde National Park , Navajo National Monument, Aztec Ruins National Monument, Canyons of the Ancients National Monument, Hovenweep National Monument, and Yucca House National Monument reaches the region the highest concentration of national parks and memorials in the United States.

Today the region settle the Navajo, who call themselves Diné call. Nearly the entire Navajo Volcanic Field is located in the Navajo Nation , its own management area. You have a large number of myths and legends, they bring the volcanic rock formations in conjunction. It is the world view of an all-encompassing dualism dominated. The earth and all forms of animate and inanimate nature, owe their origin in the idea of the interaction of Navajo Nohosdzáán (earth) and Yadihil (heaven). The individual processes are distinguished in creating, female, and destructive, male factors. In a traditional to a tsé na'alkaah scale (rock doctrine) designated ethnic geology of the Diné statement, the volcanic formations of the Navajo Volcanic Fields as by the violent (male) interaction of magma from the earth are described with water originating from the sky. The rocks in the chimneys were then exposed by interaction of the (female, coming from the ground) uplift of the Colorado Plateau with the (male, coming from the sky) erosion. This classification of scientific geology is used in schools and colleges of the Diné to integrate the teaching of science in the culture of the Diné.[5]

Literature edit

Steven Semken: BlackRock protuding up: The Navajo Volcanic Field . In: New Mexico Geological Society Guidebook . 54th Field Conference, Geology of the Zuni Plateau, 2003, pp. 133-138 (online: Field Guide to the Navajo Volcanic Field PDF file, 1.14 MB).

References edit

  1. ^ a b c Michael F. Roden, Douglas Smith, V. Rama Murthy: Chemical constraints on lithosphere composition and evolution beneath the Colorado Plateau, In: Journal of Geophysical Research , Volume 95, No. B3, 1990, Pages 2811-2831
  2. ^ Douglas Smith, William L. Griffin, et al. trace element zonation in garnets from The Thumb: heating and melt infiltration beneath the Colorado Plateau . In: Contributions to Mineralogy and Petrology . 107, 1991 , pp. 60-79
  3. ^ Paul T. Delaney: Ship Rock, New Mexico - the vent of a violent volcanic eruption . In: Beus, SS (eds): Geological Society of America Centennial Field Guide, Rocky Mountain Section , Volume 2, Boulder, Co., 1987, pp. 411-415
  4. ^ Wohletz, K. and Heiken, G.: Volcanology and geothermal energy, University of California Press, Berkeley, 1992, p 432
  5. ^ a b c d e Steven Semken: BlackRock protuding up: The Navajo Volcanic Field, In: New Mexico Geological Society Guidebook. 54th Field Conference, Geology of the Zuni Plateau, 2003, pp. 133-138 (online: Field Guide to the Navajo Volcanic Field PDF file, 1.14 MB).
  6. ^ a b Douglas Smith, Susan Levy: Petrology of the Green Knobs diatremes and implications for the upper mantle below the Colorado Plateau, In: Earth and Planetary Science Letters, Volume 29 (1976), pages 107-125
  7. ^ a b c Michael F. Roden: Origin of coexisting minette and ultramafic breccia, Navajo volcanic field . In: Contributions to Mineralogy and Petrology . 77, 1981 , pp. 195-206
  8. ^ Thomas R. McGetchin, Leon T. Silver dike A crustal-upper mantle model for the Colorado Plateau based on observations of crystalline rock fragments in the Moses Rock . In: Journal of Geophysical Research . 77, 1972 , pp. 7022-7037
  • 1↑ a b c Michael F. Roden, Douglas Smith, V. Rama Murthy: Chemical constraints on lithosphere composition and evolution beneath the Colorado Plateau . In: Journal of Geophysical Research , Volume 95, No. B3, born 1990, Pages 2811-2831
  • 2↑ Douglas Smith, William L. Griffin, et al. trace element zonation in garnets from The Thumb: heating and melt infiltration beneath the Colorado Plateau . In: Contributions to Mineralogy and Petrology . 107, 1991 , pp. 60-79.
  • 3↑ Paul T. Delaney: Ship Rock, New Mexico - the vent of a violent volcanic eruption . In: Beus, SS (eds): Geological Society of America Centennial Field Guide, Rocky Mountain Section , Volume 2, Boulder, Co., 1987, pp. 411-415
  • 4↑ Wohletz, K. and Heiken, G.: Volcanology and geothermal energy . University of California Press, Berkeley, 1992 , p 432nd
  • 5↑ a b c d Steven Semken: BlackRock protuding up: The Navajo Volcanic Field
  • 6↑ a b Douglas Smith, Susan Levy: Petrology of the Green Knobs diatremes and implications for the upper mantle below the Colorado Plateau . In: Earth and Planetary Science Letters , Volume 29 (1976), pages 107-125
  • 7↑ a b c Michael F. Roden: Origin of coexisting minette and ultramafic breccia, Navajo volcanic field . In: Contributions to Mineralogy and Petrology . 77, 1981 , pp. 195-206.
  • 8↑ All statements by Steven Semken: BlackRock protuding up: The Navajo Volcanic Field , with further references
  • 9↑ Thomas R. McGetchin, Leon T. Silver dike A crustal-upper mantle model for the Colorado Plateau based on observations of crystalline rock fragments in the Moses Rock . In: Journal of Geophysical Research . 77, 1972 , pp. 7022-7037.

Kid edit

Background: See: here, here and here

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