Collaborative Research: Three Dimensional Magmatic Strain within Laccoliths, Bysmaliths, and Sills in the Henry Mountains, Utah

合作研究：犹他州亨利山脉的 Laccoliths、Bysmaliths 和 Sills 内的三维岩浆应变

• 批准号: 0003574
• 负责人: Sven Morgan
• 金额: $ 5.6万
• 依托单位: Central Michigan University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-01-01 至 2003-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0003574&HistoricalAwards=false
• 关键词: Collaborative; Research; Three; Dimensional; Magmatic

EAR-0003574EAR-0003463This project is designed to understand the three-dimensional fabrics and strain associated with magmatic forceful expansion by comparing simple natural and experimental examples. The project involves data collection using: 1) anisotropy of magnetic susceptibility (AMS), 2) shape preferred orientations (SPO), 3) computed X-ray tomography (X-ray CT), 4) field measurements on the magmatic fabrics and strains associated with sills, laccoliths, and bysmaliths in the Henry Mountains, Utah, and 5) lab measurements on particles within artificial flows. The Henry Mountains intrusives are Oliogocene - Miocene age and intruded the upper crust of the Colorado Plateau, which is a late Paleozoic and Mesozoic section of flat-lying sandstones and shales.The goal is to relate magmatic fabrics to the displacement of the wallrocks caused by magmatic intrusion (inflation), and the intrusives in the Henry Mountains provide the best opportunity to understand this fundamental process. The floors, walls, interiors, and roofs of these intrusions are all very well exposed in the desert plateau of southern Utah. These plutons have raised the overburden by either bending the overburden or faulting the overburden immediately above the intrusion. The shapes of the intrusions represent a complete gradation between sills and laccoliths. By documenting the magmatic fabric in these bodies, the temporal fabric development of the intrusions is being interpreted and related to steps in the evolution of flow in the physical models.The boundary conditions of intrusion are well understood: laccoliths, bysmaliths, and sills intruded into the undeformed, horizontal strata of the Colorado Plateau. The strata act as markers to record the translation, rotation, and internal strain caused by magma intrusion. Moreover, the plutons intruded into a part of the Colorado plateau that has not experienced regional deformation. This setting precludes tectonic forces being involved with emplacement and allows an interpretation that unambiguously describes fabrics in terms of magmatic processes.The project involves a detailed field study to document the foliation and lineation within these intrusions. In addition, the three-dimensional SPO of the phenocrysts is being recorded and the intrusions are being sampled for AMS. The AMS technique will be corroborated by X-ray CT techniques, which will allow the documentation of the orientation and spatial distribution of magnetite on the same samples. The field studies are being conducted in tandem with physical experiments of non-uniform flows. These intrusives are the perfect examples to be modeled since their shapes are simple and known, and the low crystal content of the magmas is well constrained. The flows that are being modeled include decelerating flow and cylindrical flow, which provide a first-order approximation of magma intruding a laccolith and a bysmalith, respectively. Passive, neutrally-buoyant markers are being placed in these experiments in order to obtain quantitative strain associated with various amounts of fluid flow into a chamber. The results are being compared with the fabrics from the Henry Mountains intrusives, which were emplaced with varying amounts of magma. Using this variety of techniques, and the ideal setting provided by the Henry Mountains, the three-dimensional fabric associated with forceful emplacement of magmatic intrusions will be understood.

EAR-0003574EAR-0003463 THIS项目旨在通过比较简单的自然和实验示例来了解与岩浆有力扩张相关的三维织物和应变。该项目涉及数据收集：1）磁化率的各向异性（AMS），2）形状优选方向（SPO），3）计算的X射线层析成像（X射线CT），4）在岩浆面料和菌株和菌株上的现场测量，与凹槽，laccoliths，laccoliths，symaliths ins the Henry Mornahs Mornahs Mornahs intahs Mornahs intah intah intahs Mornahs和5亨利山脉的侵入物是奥族新世时代的年龄，并侵入了科罗拉多高原的上皮，这是扁平层砂岩和页岩的晚古生代和中生代的晚期，目的是将岩浆织物与元素造成的岩浆造成的材料相关联（与杂志的流离失所）相关联（杂志），并融入了杂物的融合（浮雕），并将其融入式的杂物（以及杂志），并将其与众不同。基本过程。这些入侵的地板，墙壁，内部和屋顶在犹他州南部的沙漠高原都非常曝光。这些岩石通过弯腰覆盖层或使覆盖层的压倒在入侵之上，从而提高了覆盖层。入侵的形状代表了窗台和laccoliths之间的完整渐变。通过记录这些物体中的岩浆织物，正在解释侵入的时间织物的发展，并与物理模型中流动演变的步骤相关。入侵的边界条件充分了解：laccoliths，bysmaliths和sills和斜纹浸入未侵入的人，侵入了未造成的层次。地层是记录由岩浆入侵引起的翻译，旋转和内部应变的标记。此外，岩石侵入了没有发生区域变形的科罗拉多高原的一部分。这种设置排除了构造力涉及驻扎，并允许一种解释，该解释明确地描述了岩浆过程中的织物。该项目涉及一项详细的现场研究，以记录这些侵入中的叶面和线条。 此外，正在记录该表晶的三维SPO，并为AMS采样了侵入。 AMS技术将通过X射线CT技术证实，这将允许在同一样品上的方向和空间分布进行文档。 现场研究是与非均匀流动的物理实验一起进行的。 这些侵入物是要建模的完美例子，因为它们的形状简单且已知，并且岩浆的低晶体含量受到良好的约束。正在建模的流量包括减速流和圆柱流，这些流量分别提供了岩浆的一阶近似，分别侵入了laccolith和bysmalith。这些实验中正在放置被动，中性的标记，以便获得与各种流体流入腔室的定量应变。将结果与亨利山脉侵入物的织物进行了比较，亨利山脉的侵入剂中有不同量的岩浆。使用这种各种技术以及亨利山脉提供的理想设置，将了解与岩浆入侵有力扩增相关的三维织物。