Electronic Theses and Dissertation

Penelitian ini dilakukan di kawasan situs cagar budaya Benteng Inong Balee, Desa Lamreh, Aceh Besar, yang berada pada lereng pesisir sangat curam dan memiliki tingkat kerentanan tinggi terhadap longsor. Tujuan penelitian ini adalah memodelkan struktur bawah permukaan dan mengidentifikasi zona berpotensi longsor menggunakan metode geofisika non-destruktif melalui integrasi Ground Penetrating Radar (GPR) dan geolistrik. Akuisisi data dilakukan pada empat lintasan untuk masing-masing metode. Metode GPR menggunakan antena frekuensi 250 MHz dan 700 MHz untuk mengidentifikasi struktur bawah permukaan dangkal, sedangkan metode geolistrik dengan konfigurasi Wenner–Schlumberger digunakan untuk memodelkan kondisi bawah permukaan hingga kedalaman sekitar 20 m. Pengolahan data GPR meliputi zero-time correction, dewow filtering, background removal, time-power gain, analisis kedalaman, dan FK migration, sedangkan data geolistrik diolah menggunakan metode Least Squares Inversion dan disusun dalam model pseudo-3D. Interpretasi dilakukan dengan mengintegrasikan hasil kedua metode dan data geologi singkapan. Hasil penelitian menunjukkan bahwa potensi longsor berkembang secara terlokalisasi namun berulang pada jarak tertentu di setiap lintasan, terutama pada jarak 50–100 m pada lintasan 1 dan 2. Mekanisme longsor yang berpotensi terjadi didominasi oleh longsor dangkal hingga translasi, yang berkembang pada batas transisi antara material pelapukan jenuh fluida dan batuan karbonatan yang lebih kompak. Tingkat pelapukan, distribusi fluida, dan keberadaan rekahan menjadi faktor utama pengontrol ketidakstabilan lereng, sehingga hasil penelitian ini dapat digunakan sebagai dasar awal mitigasi bencana dan upaya konservasi kawasan Benteng Inong Balee.

This study was conducted at the Benteng Inong Balee cultural heritage site in Lamreh Village, Aceh Besar, an area located on an extremely steep coastal slope with high landslide susceptibility. The objective of this study was to model subsurface structures and identify potential landslide zones using non-destructive geophysical methods through the integration of Ground Penetrating Radar (GPR) and geoelectric techniques. Data acquisition was carried out along four transects for each method. The GPR survey employed 250 MHz and 700 MHz antennas to characterize shallow subsurface features, while the geoelectric survey used a Wenner–Schlumberger configuration to model subsurface conditions to depths of approximately 20 m. GPR data were processed through zero-time correction, dewow filtering, background removal, time-power gain, depth analysis, and FK migration. Meanwhile, geoelectric data were processed using the Least Squares Inversion method and compiled into a pseudo-3D model. Interpretation was performed by integrating the results of both geophysical methods with geological outcrop observations. The results indicate that landslide potential develops in a localized yet recurrent pattern along each transect, particularly at distances of 50–100 m on transects 1 and 2. The dominant landslide mechanisms are shallow to translational slides, occurring at the transition zone between fluid-saturated weathered materials and more compact carbonate rocks. These findings suggest that the degree of weathering, fluid distribution, and fracture development are the primary controlling factors of slope instability, highlighting the significance of this study as a preliminary basis for landslide mitigation and conservation efforts in the Benteng Inong Balee area.