Jonathan Macarius, Mjemah Ibrahimu C, Kimambo Offoro N, Hamad Amina A
Department of Geography and Environmental Studies, College of Natural and Applied Science, Sokoine University of Agriculture, Morogoro, Tanzania.
Heliyon. 2024 Sep 24;10(19):e38346. doi: 10.1016/j.heliyon.2024.e38346. eCollection 2024 Oct 15.
The study sought to utilise Geographic Information Systems (GIS), Remote Sensing, and a blend of manual and automatic techniques to delineate and analyse the spatial distribution and orientation of lineaments within the terrain of Mpwapwa District. The study employed various techniques, including the Optimum Index Factor (OIF), Band Combination, Principal Component Analysis (PCA), and Directional Filtering on the Landsat 8 imagery, and Hill Shading technique was used on Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM). These techniques were employed in the processing steps for both manual and automatic lineament extraction, utilizing various software tools. Lineament control and validation were executed using digitized geological maps, topographical maps, and Google Earth images. The results revealed lineaments with a total length of 2060.6 km, non-uniformly distributed and predominantly present in hard rock lithologies, such as migmatitic granite, migmatitic biotite gneiss, biotite gneiss, granitoid gneiss, and porphyroblastic gneiss. The findings further indicate that NE-SW and NW-SE are the dominant lineament trends. Additionally, the study revealed that areas with medium, high, and very high lineament density and intersection are primarily located in the southwest and northeast parts of the Mpwapwa District. Meanwhile, regions with low lineament density are spread through the entire district. In this study, GIS and remote sensing emerged as valuable tools for identifying and mapping lineaments within a challenging hydrogeological setting. Findings from this study will serve as a foundational framework for subsequent geological and hydrogeological investigations in the area of study.
该研究旨在利用地理信息系统（GIS）、遥感技术，以及手动和自动技术相结合的方法，来描绘和分析姆普瓦普瓦区地形内线性构造的空间分布和走向。该研究采用了多种技术，包括最佳指数因子（OIF）、波段组合、主成分分析（PCA），以及对陆地卫星8号影像进行方向滤波，同时在航天飞机雷达地形测绘任务数字高程模型（SRTM DEM）上使用了山体阴影技术。这些技术被应用于手动和自动线性构造提取的处理步骤中，利用了各种软件工具。线性构造的控制和验证使用了数字化地质图、地形图和谷歌地球图像来执行。结果显示，线性构造的总长度为2060.6公里，分布不均匀，主要存在于混合花岗岩、混合黑云母片麻岩、黑云母片麻岩、花岗质片麻岩和斑状片麻岩等硬岩岩性中。研究结果进一步表明，东北-西南和西北-东南是主要的线性构造走向。此外，该研究还表明，线性构造密度和交叉点处于中等、高和非常高的区域主要位于姆普瓦普瓦区的西南部和东北部。与此同时，线性构造密度低的区域遍布整个地区。在这项研究中，GIS和遥感成为在具有挑战性的水文地质环境中识别和绘制线性构造的宝贵工具。本研究的结果将作为后续在研究区域进行地质和水文地质调查的基础框架。
