Magnetic fabric of the Parashi stock and related dyke swarm, Alta Guajira (Colombia): The Caribbean-South American plates oblique convergence

IF 0.9 4区地球科学 Q3 GEOLOGY

Andean Geology Pub Date : 2021-05-31 DOI:10.5027/ANDGEOV48N2-3332

C. Bustamante, C. Archanjo, A. Cardona, Marcela Restrepo

引用次数: 3

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 (

查看原文本刊更多论文

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

利用磁化率各向异性（AMS）和无磁滞剩磁（AAR）来评估位于哥伦比亚西北部的Parashi岩群和相关岩脉群的侵位历史。4.5×10-2 SI的平均磁化率，以及等温剩磁和具有净Verwey和居里跃迁的热磁曲线提供的低矫顽力分量，表明多畴磁铁矿记录了各向异性方向。AMS和AAR椭球的相似方向和形状表明不存在具有相反组构的非常细的磁铁矿。磁性叶理是这些岩石中定义最好的组构元素，勾勒出一个同心结构，平行于深成岩体的东北-西南方向延伸。岩堆和岩脉的结晶年龄（51-47Ma），以及侵位压力的确定表明，岩堆和岩墙群可能同时形成，它们侵位在浅地壳中(

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Andean Geology 地学-地质学

CiteScore

3.90

自引率

0.00%

发文量

审稿时长

>12 weeks

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.