C. Bustamante, C. Archanjo, A. Cardona, Marcela Restrepo
{"title":"上瓜希拉省(哥伦比亚)Parashi岩群和相关岩脉群的磁性结构:加勒比-南美板块斜辐合","authors":"C. Bustamante, C. Archanjo, A. Cardona, Marcela Restrepo","doi":"10.5027/ANDGEOV48N2-3332","DOIUrl":null,"url":null,"abstract":"Anisotropy of magnetic susceptibility (AMS) and anhysteretic remanence (AAR) were used to evaluate the emplacement history of the Parashi stock and related dyke swarm situated in NW Colombia. The average magnetic susceptibility of 4.5×10-2 SI, in conjunction with low-coercivity components provided by the isothermal remanence and thermomagnetic curves with net Verwey and Curie transitions, indicates that multidomain magnetite records the anisotropy directions. The similar orientation and shape of the AMS and AAR ellipsoids indicate the absence of very fine magnetite with an inverse fabric. The magnetic foliation is the best-defined fabric element in these rocks and outlines a concentric structure, elongated parallel to the NE-SW direction of the pluton. Crystallisation age of the stock and dykes (51-47 Ma), along with pressure of emplacement determination indicate that the stock and the dyke swarm probably formed simultaneously, and they were emplaced in the shallow crust (","PeriodicalId":49108,"journal":{"name":"Andean Geology","volume":"48 1","pages":"219"},"PeriodicalIF":0.9000,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":"{\"title\":\"Magnetic fabric of the Parashi stock and related dyke swarm, Alta Guajira (Colombia): The Caribbean-South American plates oblique convergence\",\"authors\":\"C. Bustamante, C. Archanjo, A. Cardona, Marcela Restrepo\",\"doi\":\"10.5027/ANDGEOV48N2-3332\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Anisotropy of magnetic susceptibility (AMS) and anhysteretic remanence (AAR) were used to evaluate the emplacement history of the Parashi stock and related dyke swarm situated in NW Colombia. The average magnetic susceptibility of 4.5×10-2 SI, in conjunction with low-coercivity components provided by the isothermal remanence and thermomagnetic curves with net Verwey and Curie transitions, indicates that multidomain magnetite records the anisotropy directions. The similar orientation and shape of the AMS and AAR ellipsoids indicate the absence of very fine magnetite with an inverse fabric. The magnetic foliation is the best-defined fabric element in these rocks and outlines a concentric structure, elongated parallel to the NE-SW direction of the pluton. Crystallisation age of the stock and dykes (51-47 Ma), along with pressure of emplacement determination indicate that the stock and the dyke swarm probably formed simultaneously, and they were emplaced in the shallow crust (\",\"PeriodicalId\":49108,\"journal\":{\"name\":\"Andean Geology\",\"volume\":\"48 1\",\"pages\":\"219\"},\"PeriodicalIF\":0.9000,\"publicationDate\":\"2021-05-31\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"3\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Andean Geology\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.5027/ANDGEOV48N2-3332\",\"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":"Andean Geology","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.5027/ANDGEOV48N2-3332","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOLOGY","Score":null,"Total":0}
Magnetic fabric of the Parashi stock and related dyke swarm, Alta Guajira (Colombia): The Caribbean-South American plates oblique convergence
Anisotropy of magnetic susceptibility (AMS) and anhysteretic remanence (AAR) were used to evaluate the emplacement history of the Parashi stock and related dyke swarm situated in NW Colombia. The average magnetic susceptibility of 4.5×10-2 SI, in conjunction with low-coercivity components provided by the isothermal remanence and thermomagnetic curves with net Verwey and Curie transitions, indicates that multidomain magnetite records the anisotropy directions. The similar orientation and shape of the AMS and AAR ellipsoids indicate the absence of very fine magnetite with an inverse fabric. The magnetic foliation is the best-defined fabric element in these rocks and outlines a concentric structure, elongated parallel to the NE-SW direction of the pluton. Crystallisation age of the stock and dykes (51-47 Ma), along with pressure of emplacement determination indicate that the stock and the dyke swarm probably formed simultaneously, and they were emplaced in the shallow crust (
期刊介绍:
This journal publishes original and review articles on geology and related sciences, in Spanish or English, in three issues a year (January, May and September). Articles or notes on major topics of broad interest in Earth Sciences dealing with the geology of South and Central America and Antarctica, and particularly of the Andes, are welcomed.
The journal is interested in publishing thematic sets of papers and accepts articles dealing with systematic Paleontology only if their main focus is the chronostratigraphical, paleoecological and/or paleogeographical importance of the taxa described therein.