Lineaments in enhanced remote sensing images: An example from the Upper Perak Valley, Perak Darul Ridwan


Author : Juhari Mat AkhirPublication : Bulletin of the Geological Society of MalaysiaVolume : 48Page : 115-119Year : 2004


Description

Bulletin of the Geological Society of Malaysia, Volume 48, June 2004, pp. 115-119

 

Lineaments in enhanced remote sensing images: An example from the Upper Perak Valley, Perak Darul Ridwan

JUHARI MAT AKHIR

School of Environmental Science and Natural Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan

 

Abstract: Linear structural features (lineaments) mapped from remotely sensed images are often used as indicators of fractures in near-surface rocks. Previous lineament mapping and interpretations of Malaysia have used aerial photographs and relatively unenhanced satellite images. Images covering the Upper part of Perak River Basin have been produced from LANDSAT MSS data using several digital image processing techniques, particularly filtering, intended to enhance the visibility of lineaments. The contrast stretched of MSS band 7 was found to be the best in displaying lineaments for the area, hence, was further processed by using directional filters. The four directionally filtered images, which contain lineaments in EW, NS, NE-SW and NW-SE direction, were used for lineament mapping. All lineaments longer than 1 km were traced and mapped at scale 1:250,000; their orientations were determined and lengths measured, and further analyzed by preparing rose diagrams for analysis, interpretation and comparison with published maps. Fracture analysis of the mapped lineaments was carried out together with its relation with rock types and mineral deposits in the study area. A good correlation, both in terms of direction and location, do exist between image lineaments and previously mapped faults. In addition, new prominent lineaments which are probably newly identified faults were delineated and recorded along with new circular features, thus, updating the structural geologic map of the area as well as to facilitate the planning of mineral exploration and identification of new mineral deposits.

 

Abstrak: Fitur struktur linear (lineamen) yang dipetakan daripada imej penderiaan jauh sering digunakan sebagai penunjuk kepada retakan batuan hampir permukaan bumi. Pemetaan dan tafsiran lineamen terdahulu di Malaysia menggunakan fotograf udara dan imej satelit yang secara relatifnya tidak ditonjolkan. Imej kawasan Hulu Lembah Perak telah dihasilkan daripada data LANDSAT MSS menggunakan teknik pemprosesan imej secara digit, terutamanya penapisan, bertujuan untuk menonjolkan maklumat lineamen. Imej MSS jalur 7 yang diregangkan kontrasnya didapati memaparkan maklumat lineamen terbaik dan dipilih untuk diproses menggunakan tapisan berarah. Empat imej hasil penapisan berarah yang mengandungi lineamen arah TB, US, TL-BD dan BL-TG, telah digunakan untuk pemetaan lineamen. Semua lineamen melebihi 1 km panjang disurih dan dipetakan pada skala 1:250,000; orientasi dan panjangnya ditentukan dan diukur, dan seterusnya dianalisis menggunakan rajah mawar, ditafsirkan dan dibandingkan dengan peta geologi yang diterbitkan. Lineamen yang dipetakan dilakukan analisis retakan dan juga mengkaji perkaitan antara ketumpatannya dengan jenis batuan dan juga longgokan mineral di kawasan ini. Wujud perkaitan yang baik, sama ada daripada segi arah dan kedudukan, antara lineamen dengan maklumat sesar yang dipetakan. Selain itu, beberapa lineamen baru yang terpapar jelas berkemungkinan merupakan sesar yang belum dipetakan turut disurih dan direkodkan di samping fitur membulat. Ini bermakna hasil kajian ini membolehkan peta struktur geologi dikemaskinikan serta memudahkan perancangan eksplorasi serta penentuan lokasi baru longgokan mineral.

https://doi.org/10.7186/bgsm48200422