{"title":"巴西南埃斯帕纳帕拉索山脉的手工和小规模金矿,利用时域电磁感应:勘探、效率和环境方面","authors":"Henrique Borgatti, Aline Tavares Melo, Luiz Guilherme Knauer","doi":"10.1590/2317-488920232022090","DOIUrl":null,"url":null,"abstract":"Gold mining has profound ties to the history of Brazilian colonization and still takes place with many communities involved in artisanal and small-scale gold mining. The most relevant gold deposits in the Southern Espinhaço Range are related to the occurrence of shear zones in the region between the cities of Diamantina and Gouveia, Minas Gerais, Brazil. Former colonial-dated gold mines were depleted; however, the use of newer prospecting practices has brought new interest in these areas. In this context, this study assesses the efficiency, environmental impacts, and economic viability of time-domain electromagnetic induction as a gold exploration method for small-scale prospecting in Gouveia county. Additionally, this study provides a characterization of the local gold mineralization and brings awareness to the prospecting community regarding environmental and legal aspects of gold mining. This article presents the results of a field campaign of prospecting efforts in which 114 metallic targets were located, 35 of which were identified as native gold. The gold samples have specific morphology, depth, and weight that suggest a hypogenic origin with a low degree of transport at eluvial levels. From an environmental perspective, the time-domain electromagnetic induction method has presented fewer impacts, related mostly to site-specific remobilization of the soil.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"30 1","pages":"0"},"PeriodicalIF":1.3000,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Artisanal and small-scale gold mining in the Southern Espinhaço Range, Brazil, using time-domain electromagnetic induction: prospecting, efficiency, and environmental aspects\",\"authors\":\"Henrique Borgatti, Aline Tavares Melo, Luiz Guilherme Knauer\",\"doi\":\"10.1590/2317-488920232022090\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Gold mining has profound ties to the history of Brazilian colonization and still takes place with many communities involved in artisanal and small-scale gold mining. The most relevant gold deposits in the Southern Espinhaço Range are related to the occurrence of shear zones in the region between the cities of Diamantina and Gouveia, Minas Gerais, Brazil. Former colonial-dated gold mines were depleted; however, the use of newer prospecting practices has brought new interest in these areas. In this context, this study assesses the efficiency, environmental impacts, and economic viability of time-domain electromagnetic induction as a gold exploration method for small-scale prospecting in Gouveia county. Additionally, this study provides a characterization of the local gold mineralization and brings awareness to the prospecting community regarding environmental and legal aspects of gold mining. This article presents the results of a field campaign of prospecting efforts in which 114 metallic targets were located, 35 of which were identified as native gold. The gold samples have specific morphology, depth, and weight that suggest a hypogenic origin with a low degree of transport at eluvial levels. From an environmental perspective, the time-domain electromagnetic induction method has presented fewer impacts, related mostly to site-specific remobilization of the soil.\",\"PeriodicalId\":9221,\"journal\":{\"name\":\"Brazilian Journal of Geology\",\"volume\":\"30 1\",\"pages\":\"0\"},\"PeriodicalIF\":1.3000,\"publicationDate\":\"2023-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Brazilian Journal of Geology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1590/2317-488920232022090\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"GEOSCIENCES, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Brazilian Journal of Geology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1590/2317-488920232022090","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
Artisanal and small-scale gold mining in the Southern Espinhaço Range, Brazil, using time-domain electromagnetic induction: prospecting, efficiency, and environmental aspects
Gold mining has profound ties to the history of Brazilian colonization and still takes place with many communities involved in artisanal and small-scale gold mining. The most relevant gold deposits in the Southern Espinhaço Range are related to the occurrence of shear zones in the region between the cities of Diamantina and Gouveia, Minas Gerais, Brazil. Former colonial-dated gold mines were depleted; however, the use of newer prospecting practices has brought new interest in these areas. In this context, this study assesses the efficiency, environmental impacts, and economic viability of time-domain electromagnetic induction as a gold exploration method for small-scale prospecting in Gouveia county. Additionally, this study provides a characterization of the local gold mineralization and brings awareness to the prospecting community regarding environmental and legal aspects of gold mining. This article presents the results of a field campaign of prospecting efforts in which 114 metallic targets were located, 35 of which were identified as native gold. The gold samples have specific morphology, depth, and weight that suggest a hypogenic origin with a low degree of transport at eluvial levels. From an environmental perspective, the time-domain electromagnetic induction method has presented fewer impacts, related mostly to site-specific remobilization of the soil.
期刊介绍:
The Brazilian Journal of Geology (BJG) is a quarterly journal published by the Brazilian Geological Society with an electronic open access version that provides an in-ternacional medium for the publication of original scientific work of broad interest concerned with all aspects of the earth sciences in Brazil, South America, and Antarctica, in-cluding oceanic regions adjacent to these regions. The BJG publishes papers with a regional appeal and more than local significance in the fields of mineralogy, petrology, geochemistry, paleontology, sedimentology, stratigraphy, structural geology, tectonics, neotectonics, geophysics applied to geology, volcanology, metallogeny and mineral deposits, marine geology, glaciology, paleoclimatology, geochronology, biostratigraphy, engineering geology, hydrogeology, geological hazards and remote sensing, providing a niche for interdisciplinary work on regional geology and Earth history.
The BJG publishes articles (including review articles), rapid communications, articles with accelerated review processes, editorials, and discussions (brief, objective and concise comments on recent papers published in BJG with replies by authors).
Manuscripts must be written in English. Companion papers will not be accepted.