巴西米纳斯吉拉斯州的淘金热：地质勘察和金块的起源

IF 0.8 4区地球科学 Q3 GEOLOGY Geology of Ore Deposits Pub Date : 2024-08-28 DOI:10.1134/s1075701524600087

Alexandre Raphael Cabral, José Maria Leal, Rogerio Kwitko-Ribeiro

{"title":"巴西米纳斯吉拉斯州的淘金热：地质勘察和金块的起源","authors":"Alexandre Raphael Cabral, José Maria Leal, Rogerio Kwitko-Ribeiro","doi":"10.1134/s1075701524600087","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Gold nuggets, loose in talus material, triggered an ongoing gold rush in the southern Serra do Espinhaço, Minas Gerais, Brazil. The talus material has abundant fragments of vein quartz in a clay-rich matrix, resting on metagreywacke of the Neoproterozoic Macaúbas Group. Quartz lodes, which truncate the metamorphic foliation of the bedrock metagreywacke, are the source of the gold nuggets, which formed after the main tectonic and metamorphic overprint of the Ediacaran–Cambrian Brasiliano orogeny. The gold nuggets are hypogene in origin, but they have a minor component of supergene gold, which occurs as dendrites of bud-like gold particles, mostly <1 µm across. Amongst the latter, apically branched hyphae of essentially pure gold are noteworthy and suggest pseudomorphism after fungi.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"36 1","pages":""},"PeriodicalIF":0.8000,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Gold Rush as it Happens in Minas Gerais, Brazil: Geological Reconnaissance and Origin of Gold Nuggets\",\"authors\":\"Alexandre Raphael Cabral, José Maria Leal, Rogerio Kwitko-Ribeiro\",\"doi\":\"10.1134/s1075701524600087\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<h3 data-test=\\\"abstract-sub-heading\\\">Abstract</h3><p>Gold nuggets, loose in talus material, triggered an ongoing gold rush in the southern Serra do Espinhaço, Minas Gerais, Brazil. The talus material has abundant fragments of vein quartz in a clay-rich matrix, resting on metagreywacke of the Neoproterozoic Macaúbas Group. Quartz lodes, which truncate the metamorphic foliation of the bedrock metagreywacke, are the source of the gold nuggets, which formed after the main tectonic and metamorphic overprint of the Ediacaran–Cambrian Brasiliano orogeny. The gold nuggets are hypogene in origin, but they have a minor component of supergene gold, which occurs as dendrites of bud-like gold particles, mostly <1 µm across. Amongst the latter, apically branched hyphae of essentially pure gold are noteworthy and suggest pseudomorphism after fungi.</p>\",\"PeriodicalId\":12719,\"journal\":{\"name\":\"Geology of Ore Deposits\",\"volume\":\"36 1\",\"pages\":\"\"},\"PeriodicalIF\":0.8000,\"publicationDate\":\"2024-08-28\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Geology of Ore Deposits\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.1134/s1075701524600087\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"GEOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geology of Ore Deposits","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1134/s1075701524600087","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOLOGY","Score":null,"Total":0}

引用次数: 0

摘要

摘要巴西米纳斯吉拉斯州南部塞拉杜埃斯平哈索（Serra do Espinhaço）的金块散落在距骨材料中，引发了持续不断的淘金热。距石材料中有大量的脉石英碎片，基质富含粘土，位于新新生代马考巴斯组的岩屑岩上。在埃迪卡拉纪-寒武纪巴西里亚诺造山运动的主要构造和变质叠压作用之后形成的石英矿脉截断了基岩玄武岩砾岩的变质褶皱，是金块的来源。金块的来源是次生金，但其中有少量超生金，以芽状金粒的树枝状出现，直径大多为 1 微米。在后者中，值得注意的是顶端分枝的基本上是纯金的菌丝，这表明它们是仿真真菌的假形态。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

摘要图片

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

Gold Rush as it Happens in Minas Gerais, Brazil: Geological Reconnaissance and Origin of Gold Nuggets

Abstract

Gold nuggets, loose in talus material, triggered an ongoing gold rush in the southern Serra do Espinhaço, Minas Gerais, Brazil. The talus material has abundant fragments of vein quartz in a clay-rich matrix, resting on metagreywacke of the Neoproterozoic Macaúbas Group. Quartz lodes, which truncate the metamorphic foliation of the bedrock metagreywacke, are the source of the gold nuggets, which formed after the main tectonic and metamorphic overprint of the Ediacaran–Cambrian Brasiliano orogeny. The gold nuggets are hypogene in origin, but they have a minor component of supergene gold, which occurs as dendrites of bud-like gold particles, mostly <1 µm across. Amongst the latter, apically branched hyphae of essentially pure gold are noteworthy and suggest pseudomorphism after fungi.

求助全文

通过发布文献求助，成功后即可免费获取论文全文。去求助

来源期刊

Geology of Ore Deposits 地学-地质学

CiteScore

1.10

自引率

14.30%

发文量

审稿时长

6-12 weeks

期刊介绍： Geology of Ore Deposits is a periodical covering the topic of metallic and nonmetallic mineral deposits, their formation conditions, and spatial and temporal distribution. The journal publishes original scientific articles and reviews on a wide range of problems in theoretical and applied geology. The journal focuses on the following problems: deep geological structure and geodynamic environment of ore formation; distribution pattern of metallogenic zones and mineral deposits; geology and formation environment of large and unique metallic and nonmetallic deposits; mineralogy of metallic and nonmetallic deposits; physicochemical and isotopic characteristics and geochemical environment of ore deposition; evolution of ore-forming systems; radiogeology and radioecology, economic problems in exploring, developing, and mining of ore commodities.