The mineralized (U bearing) rocks, near Bangurdih area, in the western part of the Singhbhum shear zone (SSZ) are strongly deformed and metamorphosed. The host and country rocks are mylonitic in nature with strong linear and planar fabrics. Surface studies indicate that the mineralized bodies are discontinuous in nature and occur sporadically. The thickness of the individual mineralized bodies is also not uniform. Present work is aimed at studying meso- and micro-scale deformational structures, their bearing on regional scale structure and their relation with the occurrences of U-mineralization in and around Bangurdih area. The area comprises predominantly of quartz–chlorite schist/quartz–chlorite–sericite schist with intercalated quartzite, meta-conglomerate and feldspathic schist of varying thickness. Apatite–tourmaline–magnetite-rich quartzite, chlorite schist and conglomerate are commonly radioactive. The uranium mineralized body at Bangurdih shows pinch-and-swell structure. Stretched thin quartz veins, observed within the sheared quartzite layers, have undergone layer parallel flow resulting in bidirectional pinch-and-swell structure lying on YZ and XZ sections of strain ellipsoid with their axes parallel and perpendicular to the shear lineation, respectively. Oriented samples were collected from quartz veins and the country rocks to prepare thin sections parallel to XY, YZ and XZ plane of strain ellipsoid from each sample for microstructural study. Aspect ratios of strain ellipses of XY, YZ and XZ sections are measured using Fry analysis. Flinn diagram shows that the rocks of the Bangurdih were subjected to bi-directional flattening (average k = 0.77), which indicates that in addition to simple shear deformation there is a shortening component perpendicular to the shear plane in this area. To correlate the strain pattern of Bangurdih with nearby areas, deformed pebbles from conglomeratic horizons and oriented samples of other rocks from Bhurkuli–Bundu and Rangamatia–Simulbera area were studied. Flinn diagram, prepared using all data, reveals that while the strain type in Bangurdih area shows intense flattening type of deformation, the Rangamatia–Simulbera area shows constrictional type of deformation (k values range from 0.57 to 0.88 and 1.02 to 2, respectively). Other locations (Bhurkuli–Bundu) in between Bangurdih and Rangamatia–Simulbera show both constriction and flattening type of strain (k values vary from 0.67 to 1.35). Therefore, it is concluded that the intense flattening type of simple shear deformation in Bangurdih area leads the ore rich layers to be stretched and detached in two directions (X and Y), which in turn, causes the mineralized body to occur intermittently with systematic trend on the surface and possibly in subsurface conditions too.

位于 Singhbhum 剪切带 (SSZ) 西部的 Bangurdih 地区附近的矿化 (U 轴承) 岩石发生强烈变形和变质。寄主和围岩本质上是糜棱质，具有强烈的线性和平面结构。地表研究表明，矿化体本质上是不连续的，并且零星出现。各个矿化体的厚度也不均匀。目前的工作旨在研究中微尺度变形结构、它们对区域尺度结构的影响以及它们与班古尔迪地区及其周围 U 型矿化发生的关系。该地区主要由石英-绿泥石片岩/石英-绿泥石-绢云母片岩组成，夹有不同厚度的石英岩、变砾岩和长石片岩。富含磷灰石-电气石-磁铁矿的石英岩，绿泥石片岩和砾岩通常具有放射性。Bangurdih 的铀矿化体显示出收缩和膨胀结构。在剪切石英岩层内观察到的拉伸薄石英脉经历了层平行流，导致位于应变椭球 YZ 和 XZ 截面上的双向挤压和膨胀结构，其轴分别平行和垂直于剪切线。从石英脉和围岩中收集定向样品，从每个样品制备平行于应变椭球的 XY、YZ 和 XZ 平面的薄片，用于微观结构研究。使用 Fry 分析测量 XY、YZ 和 XZ 截面的应变椭圆的纵横比。弗林图显示班古尔迪的岩石受到双向压扁（平均k = 0.77)，这表明除了简单的剪切变形外，该区域还有垂直于剪切平面的缩短分量。为了将 Bangurdih 的应变模式与附近地区相关联，研究了来自砾岩层的变形卵石和来自 Bhurkuli-Bundu 和 Rangamatia-Simulbera 地区的其他岩石的定向样品。使用所有数据制作的 Flinn 图显示，虽然 Bangurdih 地区的应变类型显示出强烈的扁平类型变形，但 Rangamatia-Simulbera 地区显示出收缩类型的变形（k值范围分别为 0.57 至 0.88 和 1.02 至 2）。Bangurdih 和 Rangamatia-Simulbera 之间的其他位置（Bhurkuli-Bundu）显示出收缩和扁平类型的应变（k值从 0.67 到 1.35 不等）。因此，可以得出结论，班古尔迪地区强烈的扁平型简单剪切变形导致富矿层向两个方向（X和Y）拉伸和分离，进而导致矿化体以系统趋势间歇发生。在地表上，也可能在地下条件下。