Average properties of ellipsoidal fabrics: Implications for two- and three-dimensional methods of strain analysis
Average properties of ellipsoidal fabrics: Implications for two- and three-dimensional methods of strain analysis
复制标题
椭圆体织物的平均特性：对二维和三维应变分析方法的影响
DOI：
10.1016/0040-1951(86)90232-5
复制
发表时间：
1986
期刊：
影响因子：
2.9
通讯作者：
J. Wheeler
中科院分区：
文献类型：
--
作者：
J. Wheeler
许多岩石含有椭球体（如卵石或还原带），其显示出各种形状和方向。在变形岩石中，这种物体可以通过使用平均椭球（这里称为“组构椭球”）的概念来进行应变分析。定义了两个织物椭球，它们是两个不同代数平均过程的结果。在椭球分布的变形过程中，组构椭球的变化就好像它们本身是物质椭球一样，因此在应变分析中具有重要意义。迄今为止，在大多数研究中，这种三维组构椭球是由岩石样品剖面上的二维平均椭球得到的。以前的工作假设，平均椭圆将近似通过一个单一的织物椭圆截面。我在这里表明，这是不是这种情况下，作为切片介绍了系统的偏见到截面椭圆数据。这种偏差与其他工作中讨论的统计误差（由于有限的样本大小和测量误差）不同，并且必须在使用截面的任何应变分析方法中加以考虑。
Many rocks contain ellipsoidal objects (such as pebbles or reduction zones) which display a variety of shapes and orientations. In deformed rocks such objects may be used for strain analysis by using the concept of an average ellipsoid (here called the “fabric ellipsoid”). Two fabric ellipsoids are defined which are the results of two different algebraic averaging processes. During deformation of ellipsoidal distributions, the fabric ellipsoids change as if they were themselves material ellipsoids and are therefore of fundamental importance in strain analysis.In most studies to date, such 3-D fabric ellipsoids have been obtained from 2-D average ellipses determined on section planes cut through the rock sample. Previous work has assumed that the average ellipses will approximate to section through a single fabric ellipsoid. I show here that this is not the case as sectioning introduces a systematic bias into the section ellipse data. This bias is distinct from the statistical errors (due to finite sample size and measurement errors) discussed in other work and must be considered in any method of strain analysis using section planes.