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Post by vegasjames on Jan 7, 2018 7:27:13 GMT -5
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Post by vegasjames on Jan 7, 2018 7:31:12 GMT -5
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Post by vegasjames on Jan 7, 2018 7:34:55 GMT -5
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Post by fernwood on Jan 7, 2018 7:51:36 GMT -5
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Sabre52
Cave Dweller
Me and my gal, Rosie
Member since August 2005
Posts: 20,466
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Post by Sabre52 on Jan 7, 2018 9:32:48 GMT -5
*L* Well it seems my childhood geology mentor was a bit more progressive in teaching theories than yours was. I remember being enthralled by his suggestion the the land masses were floating about the planet. Really never thought about continental drift much at all except as a theory in Geology class, until the late 60's when I was on a museum fish collecting trip to Baja and met a team of geologists measuring drift down by the Bay of Los Angeles. Fascinating stuff to think about....Mel
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Post by 1dave on Jan 7, 2018 10:08:29 GMT -5
Am loving this discussion of strewn fields, possible impact sights, etc. Information contained in the links is very good. I enjoy contemplating what strewn fields look like after a billion years of geologic processes. Impacts, erosion, deposition, continental collision, subduction, volcanism, stretching, compressing, - That is what creates our favorite rock hunting places!
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Post by 1dave on Jan 7, 2018 10:22:27 GMT -5
And all because of the loss of a horseshoe nail! The great thing about science is people keep digging. Science "knew" blood falls was caused by bacteria - until they finally found another answer.
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Post by 1dave on Jan 7, 2018 10:38:57 GMT -5
THAT IS WORTH REPRINTING!
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Tommy
Administrator
Member since January 2013
Posts: 12,665
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Post by Tommy on Jan 7, 2018 11:20:55 GMT -5
1dave - I love this thread you posted - or should I say both halves of this thread It's yours and I try not to meddle but would you mind if I split the posts into two threads? "Bucket List" would stay here and a new one would be created in the general rocks area "Origins of Copper."
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Post by fernwood on Jan 7, 2018 13:11:35 GMT -5
1dave - I love this thread you posted - or should I say both halves of this thread It's yours and I try not to meddle but would you mind if I split the posts into two threads? "Bucket List" would stay here and a new one would be created in the general rocks area "Origins of Copper." I was hoping someone would suggest/offer to do this.
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Tommy
Administrator
Member since January 2013
Posts: 12,665
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Post by Tommy on Jan 7, 2018 13:30:51 GMT -5
Yes- I had several others also contact me and say "yes please" so I went ahead and dun it. Hopefully my friend 1dave will forgive me for not waiting
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Post by 1dave on Jan 7, 2018 14:33:27 GMT -5
Yes- I had several others also contact me and say "yes please" so I went ahead and dun it. Hopefully my friend 1dave will forgive me for not waiting (Hoarse from screaming NOOOOOO!) Just kidding. Thanks to fernwood for posting www.weismuseum.org/uploads/3/4/9/3/34934999/flambeau_revised_final_20140719.pdfThinking about how it came to be - 1. Impact - otherwise no copper. 2. subduction to become part of volcanic system 3. volcanic eruptions, first basalt, then as silica increased changed to rhyolite. 4. interaction with other elements to form copper minerals 5. Compression from continental collision to compress cone into linear form, then tip it on it's side. 6. discovering the material.
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Post by fernwood on Jan 7, 2018 14:46:11 GMT -5
1dave Great summary of the process there.
The pit was pretty amazing. With binoculars, one could see veins of minerals at times.
Though not mentioned in the paper, a huge price was paid. Many of the properties near the mine have contaminated water now. One includes a WI Sate building, which remains active. Apparently something did not work out as planned. Some of the properties were purchased by the mining company, as compensation to the owners.
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Post by vegasjames on Jan 7, 2018 16:46:37 GMT -5
That was the other thing I was thinking was radioactive decay, which is still going on in the Earth. I was trying to find what decays in to copper when I found those other links.
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Post by vegasjames on Jan 7, 2018 16:50:24 GMT -5
And how much of the metal has come back to the surface from magma?
Also keep in mind that a lot of ore deposits are found in faults. Around here many of the mines are located on thrust faults where the lower layers of material are thrust upward bringing them above the previous surface.
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Post by 1dave on Jan 8, 2018 11:23:40 GMT -5
Huge amounts of copper have been swept up from the Pacific Ocean floor as the Andes Mountains were formed in Chile and Peru. Have you noticed most copper mines are bowl shaped? Why that configuration? Why such concentration in that place AND unusual combinations of other normally scarce metals? www.thebalance.com/the-world-s-20-largest-copper-mines-2014-23397451. At present the world’s largest copper producer, the Escondida mine in Chile's Atacama desert accounts for 5 percent of total global copper mine production. Gold and silver are extracted as by-products from the ore. 2. The Grasberg mine, located in the highlands of Indonesia's Papua province, is the world's largest gold mine and second-largest copper mine. Operated by PT Freeport Indonesia Co., the mine is a joint venture between Freeport McMoRan (90.64 percent) and the Indonesian government (9.36 percent). 3. The Morenci mine in Arizona is the largest copper mine in North America. Operated by Freeport McMoRan, the mine is jointly owned by the company (85 percent) and Sumitomo Affiliates (15 percent). Morenci opened for operation in 1872 and now made up of three mining pits 4. Buenavista, also known as Cananea copper mine, located in Sonora, Mexico, is the world’s second-biggest copper mine by reserve. The open-pit mine contains 27 million metric tons of copper reserve. Opened in 1899, Cananea is one of the oldest open-pit mines in North America and is currently owned and operated by the Southern Copper Corporation (SCC), a subsidiary of Grupo Mexico. 5. Cerro Verde copper mine, located 20 miles southwest of Arequipa in Peru, is the seventh-largest copper mine in the world. The open-pit mine contains an estimated 12.9 million metric tons of recoverable copper. Cerro Verde has been operational since 1976. 6. Chile's second-largest copper mine, Collahuasi, is a owned by a consortium of Anglo American (44 percent), Glencore (44 percent), and Mitsui + Nippon (12 percent). Collahuasi mine produces copper concentrate and cathodes as well as molybdenum concentrate. Most of the concentrate produced at Collahuasi is sold to smelters in China for further refining.0. 7. The Antamina copper-zinc mine is located 170 miles north of Lima. Silver, bismuth, molybdenum, and lead are also separated from the ore produced at Antamina. Jointly owned by BHP Billiton (33.75 percent), Teck (22.5 percent), Glencore (33.75 percent), and Mitsubishi Corp. (10 percent), the mine is scheduled to cease production in 2019. 8. Las Bambas Peru has Bambas has mineral reserves of 7.2 million metric tons of copper and mineral resources of 12.6 million metric tons. The mine's operators estimate that in coming years, more than 2 million metric tons of copper will be produced in concentrate. Mine operators had to move 75 million tons of material in 2014 before commencing mining operations. They estimate that the Las Bambas operation will last more than 20 years since its exploration potential is considerable; only 10 percent of the property has been explored so far. 9. Polar Division (Norilsk/Talnakh Mills) - Russia The mine is operated as part of the Polar Division of MMC Norilsk Nickel. Located in Siberia, you wouldn't want to work here unless you really like the cold. The underground nickel mine began production in the 1930s and is a source of cobalt, gold, silver, and platinum group metals, as well as copper. 10. El Teniente, The world's largest underground mine, is located in the Andes of central Chile. Owned and operated by Chilean state copper miner Codelco, El Teniente has been mined since the 19th century and is now comprised of more than 1,500 miles of tunnels
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Post by vegasjames on Jan 8, 2018 16:36:53 GMT -5
Our copper mines out here are tunnels, but are also in hard rock. Maybe the do the pits because the ground is not stable for tunneling or it is just faster and easier to remove the material.
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Post by 1dave on Jan 8, 2018 17:50:33 GMT -5
Our copper mines out here are tunnels, but are also in hard rock. Maybe the do the pits because the ground is not stable for tunneling or it is just faster and easier to remove the material. I think the metals are in the upper portion. I heard when they got ready to close down Bingham Canyon They marked and mined all the fractures that contained gold, mined them, then closed it down.
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Post by youp50 on Jan 8, 2018 22:03:01 GMT -5
I am pondering this...
On the subject of open pit mining. What shape should they be? The bowl is the only practical shape. The payload of modern mining dumptrucks exceeds 65tons. They are huge and needs lots of room to operate. No sharp turns and no backing up.
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Post by Rockoonz on Jan 8, 2018 23:47:17 GMT -5
I bought my 24 inch saw from a former employee of the Stillwater mine in Montana, Platinum related minerals along with some gold and copper. He claimed it is all from a large meteor strike long ago. He gave me a small bit of ore, supposedly from a rhodium rich part of the reef. Boring grayish quartz but flecks of the metal here and there.
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