Shulou(Shulou.com)11/24 Report--

Gold (Aurum) is a metal element, the element symbol is Au, the atomic number is 79. Perhaps there is providence in the dark. As one of the earliest metals used by human beings, gold has been recognized and highly valued in prehistoric times. after all, who can not like gold, which is brilliant and not easy to change its nature? In that era of material scarcity (well, although gold is also scarce now), this metal was often used in important ceremonies such as decorations and sacrifices of the rich and powerful. The ancient seal Zen book, with water and gold powder as clay, was used to seal the jade ultimatum. it was said in the "Custom Tong is losing the seal of the father of Mount Tai Zen Liang" in the Han Dynasty: "the record of the stone is his own achievements." or: gold and silver rope, seal. " [1]

In the Neolithic period, the ancients mixed natural gold grains with plant juice, painted them on the surface of stone tools for decoration, and could also show the status of the master, which should be the earliest clay gold process.

From the 6th century to the 1st century, gold began to be used in the form of money. The earliest known place to use gold as currency was Lydia. In China during the 6th or 5th centuries before, a kind of gold coin called "Yu" has been in circulation in the State of Chu. "Yi" is the name of the capital city of Chu, and "Yi" is the unit of monetary weight, which is the earliest gold coin known to be unearthed in China. [2]

In addition to being used as a currency, the improvement of technology has also enriched the artistic attribute of gold because of its good malleability and plasticity. In the Mycenaean cultural relic exhibition area of the National Archaeological Museum in Athens, there is the famous "Agamemnon Gold Mask" (Mask of Agam-emnon). Its image is a gold mask made according to its appearance after the death of King Agamemnon, which is the best proof of the mighty Mycenaean civilization. [3]

As an ancient civilization, although we are thousands of miles away from Greece, we happen to coincide in the use of gold. In the Sanxingdui site in 2020 (Sanxingdui site: the upper limit is 4500 ±150years ago, roughly lasting to about 3000 years ago, that is, from the late Neolithic Age to the Xia and Shang periods of the Central Plains, it is an important site of China's ancient Shu culture.) in the archaeological excavation team of the sacrificial area, a series of important gold relics, such as gold masks and golden scepters, have been unearthed, which can be seen in the worship of gold in the ancient Shu civilization. [4]

It can be said that, whether in ancient and modern times or at home and abroad, the love for gold is deep and long-lasting. "the diamond is everlasting" may be more appropriate to describe gold, so that people even try to develop this rare precious metal and even make it into painted pigments to decorate porcelain, lacquer ware and other handicrafts.

The peach of the blue golden porcelain bowl burns its bloom. When the son returns, it is suitable for his family. Marriage is the first joy of the four happy events in ancient China. In the ancient Ningbo area, a kind of glowing dowry is indispensable, which is mud and gold paint. As the first batch of non-heritage in China, clay gold paint covers gold decoration, combined with placer gold, gold grinding, silver grinding, Lei powder, gold painting, gold carving, mica, green, blue and other handicraft techniques, magnificent and brilliant. [5]

Ningbo lacquer gold wood carving so how is gold formed? Before we look at the glittering gold mine, let's look up at the vast expanse of space. according to current research, nuclear fusion (fusion) in stars increases the number of protons in the process of "melting" nuclei, forming elements with a larger atomic number.

However, this reaction is not infinite, and the nuclear fusion reaction of stars can last until the formation of iron nuclei. The iron nucleus is the most stable of all heavy elements, and when the mass of the star is large enough, it can continue to promote the fusion of the iron nucleus, and when it promotes the fusion reaction of the iron nucleus, it will produce a supernova explosion at the same time, at that moment, it will bloom the most brilliant light at the end of life. At the same time, the core will continue to capture neutrons, producing elements with a larger atomic number than iron atoms, as well as heavy metals at the bottom of the periodic table, as well as mouthwatering precious metals. [6]

But is all the gold generated in it? The answer is still not accurate. Maybe the supernova explosion did produce some gold, but this does not explain why there are so many elements in the universe with a larger atomic number than iron. So scientists discovered another sneaky alchemist "neutron star", or "double neutron star system" in the universe.

When a supernova explodes, the inner core of the star is squeezed by strong gravity, and the protons and electrons inside are forced to fuse to form neutrons, turning the core into a neutron star. Neutron stars are extremely dense celestial bodies, and the mass of neutron stars can reach hundreds of millions of tons with a spoon of matter. If two neutron stars meet in the universe, they will gradually get closer to each other under the action of gravity and eventually merge together, causing neutron star fusion. In the process of merging neutron stars, a large number of elements with large atomic numbers such as gold and silver will be produced.

Both neutron star fusion and supernova explosions can produce gold, but their "output" is not of the same order of magnitude. If supernova explosions can produce gold the size of the moon, then neutron star fusion can produce gold the size of Jupiter. Tens of thousands of times more than the former, it can be called the strongest alchemist in the universe! However, supernova explosions and neutron star fusion (the fusion of two neutron stars requires the accidental collision of two neutron stars, which occurs only once every 100 million years), this astronomical phenomenon is rare in the universe. this is why heavy metal elements, including gold, are so low in the universe that they are faint, so they are expensive. [7]

After appreciating the charm of deep space, let's look down at the deep earth we love. In the early days of the formation of the earth 4.5 billion years ago, our earth was still a large melting pot. Small celestial bodies with some metal elements in the universe were melted when it hit the earth, and the precious metals were also left in this "furnace." because of its high density, liquid iron flows to the core of the earth, forming the core of the earth. Because of the high density of gold, heavy matter is concentrated in the center of the earth, and the molten liquid gold sinks to the center of the earth.

As a result, gold, which is already scarce in the universe and even less on earth, is only about 1% in the earth's crust, but it accounts for 99% of the total gold in the earth's core. And you don't think about digging through the core to open the mine, not to mention the technical difficulty is full, the extracted gold is also very radioactive, as an ornament, the words show is quite show, but cool will also cool quickly. [8]

As a result, people focus on the few "1%" left in the earth's crust. Fortunately, China is one of the top three gold-rich countries in the world, so there is no need to watch others eat grapes. Since the 1970s, China has gradually carried out systematic geological exploration for gold resources. Under the scientific research activities of the geological research brigade for decades, the distribution and genesis of gold deposits in China have finally been systematically sorted out.

Combined with the location map and geological structure map of gold deposits in China, it can be clearly seen that gold deposits in China are mainly distributed in the boundary zone between platform and geosyncline, the uplift zone inside the geosyncline, and the deep-cut control zone of large faults (often the junction of different secondary geotectonic units). It is obvious that the genesis of gold deposits is closely related to geological tectonic activities. [9]

For example, the most important gold metallogenic belt-Lujiaodong metallogenic belt. The belt is located in the eastern Shandong uplift area of Jiaoliao uplift, where Neo-Archean and Proterozoic basement metamorphic rock series are widely exposed. The magmatic tectonic activity in the area is frequent. After multi-stage tectono-magmatic thermal events, the Archean metamorphic rock series formed mixed granite and crust source remelting granite, which provided ore source and heat source for Jiaodong gold mineralization. The unique geological advantages make this region stand on the finish line as soon as it is born, and become the largest gold base in China at present, and it is really an example of "living on talent". [10]

The main tectonic framework and distribution map of granitoids in Shandong Province, and the Lujiaodong metallogenic belt is also located in North China. North China is dominated by the North China block, the north is the Tianshan-Xingmeng orogenic system, and the south-southeast is the Qinling-Dabie-Sulu orogenic system. Generally, it is located at the confluence of paleo-Asia, Tethys and circum-Pacific tectonic systems, with a long history of geological evolution, frequent magmatic activity and superior ore-forming geological conditions. its connotation covers important metallogenic provinces such as North China, Daxinganling, Qinling-Dabie-Sulu and so on. The area is rich in mineral resources. More than 160 minerals and more than 15000 mineral areas have been discovered since the founding of the people's Republic of China, which constitute a number of important national mineral resource bases. [11]

The gap between the distribution map of metallogenic units in North China and the earth is so large. The Lujiaodong metallogenic belt is not only "born with a heaven-falling vision", but also properly stood on the shoulders of giants, just like destiny. Jiaodong is also at the junction of the two tectonic domains of the Pacific Rim and Paleo-Tethys.

The subduction of the Mesozoic Pacific plate to the Eurasian plate and the frequent activity of the Tan-Lu fault led to the development of a series of NE-NNE directions in Jiaodong area (tip: NE-NNE is the strike of the fault, which refers to the direction of the fault in the plane, that is, the direction of the fault in the plane, NE refers to the NE direction, and NNE refers to the NE direction, which is between the north and NE (45 degrees), more northerly. It's a geological term. ) compressive and torsional fracture. Due to the intense crust-mantle interaction with diagenesis and mineralization, the activation, migration and enrichment of gold components in the Jiaodong Group have become an important source bed for gold deposits in Jiaodong area. Under the action of compressional tectonic stress, the surface uplift and granite intrusion activate the ore-forming materials, resulting in the formation of gold deposits in the favorable areas of NE-NNE tectonic mineralization. [12]

The Tan-Lu fault zone and the East Asian continent after the combination of Mesozoic era

Map of Mulu metallogenic belt and geotectonic location in Jiaodong

Gold is obtained by melting and reengineering as soon as the star is broken into the dust on the side map of the gold orebody in the central and eastern Rushan area. Born from the bright moment of the universe, Jin, like a traveler in a foreign land, listened to the roar of the Nile Valley in ancient Egypt, felt the gentle breeze of the Mesopotamian plain, and looked at the rise and fall of the ancient Roman Empire. It also witnessed the ebb and flow of the land of China, which does not change with time or environment, shining, it comes from the starry sky, and tells history.

reference

[1] Gold clay. Encyclopedia (baidu.com)

[2] Kim Encyclopedia (baidu.com)

[3] Agamemnon gold mask. Encyclopedia (baidu.com)

[4] Sanxingdui gold mask. Encyclopedia (baidu.com)

[5] Pan Lei, Shao Liang and Wei Yifei. Inheritance and development of Ningbo clay gold lacquer [J] Chinese raw lacquer. 2020pr 39 (03)

[6] Zhong Ming talks about science. How did gold form? Are there any planets in the universe full of gold?. 2020-12-20. NetEase subscription (163.com)

[7] Encyclopedia of the Universe. How does gold, which is heavier than other metals, come into being in the universe?. Keep an eye on science. Sina News (sina.com.cn)

[8] Environmental protection equipment in Beiye. How gold is formed. Zhihu.com

[9] Wang Hao, Zhang Xiaoyan and Yang Qinghai. General situation of gold deposit distribution in China [J] Geological science and technology information. 1989, (04)

[10] Land and Resources physical Geological data Center. Distribution characteristics of gold resources in China and selection of national physical geological data [J] Modern mining industry. 2016pr 32 (03)

[11] Li Junjian Peng Yi Zhang Tong. Division of metallogenic units in North China [J] Geology of North China. 2021 Jing 44 (03)

State key Laboratory of Geological processes and Mineral Resources, China University of Geosciences (Beijing). Plate collision mineralization and prospecting direction of gold in Mulu metallogenic belt, Jiaodong. 2011 Jol 32 (02)

This article is from the official account of Wechat: stone popular Science Studio (ID:Dr__Stone). Author: Bian Zhou

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