Engineering Geological Setting and Risk Evaluation of the Aghdam District, Azerbaijan

This study presents a comprehensive engineering–geological assessment of the Aghdam district, Azerbaijan, based on field investigations, laboratory analyses, and morphometric–hydrographic mapping. A total of 11 geotechnical boreholes, with depths ranging from 3.0 to 15.0 m and a cumulative depth of 90.0 m, were drilled by “Engineer Geolog” MMC. Soil samples obtained from Late Quaternary deluvial–proluvial (dpQIV) and Middle Quaternary alluvial–proluvial (apQII) deposits were tested to determine their physical and mechanical properties. The dpQIV deposits were found to have a silty–clayey sand composition of medium plasticity (CL–CI type), with moderate density and poor drainage conditions. The apQII deposits, in contrast, are dominated by clayey–silty soils with high plasticity (CI–CH type), higher natural unit weight, and increased susceptibility to settlement and swelling when saturated. Gravelly apQII deposits contain a sand– silt matrix of low plasticity (CL–ML type) and display favorable drainage and stability characteristics. Shear strength tests revealed that dpQIV deposits exhibit moderate cohesion (average 32 kPa) and a friction angle of 22°, whereas apQII deposits show higher cohesion (average 51 kPa) but a lower friction angle (21°), reflecting their clay-rich nature. In addition to soil properties, thematic maps generated using ArcMap including elevation, slope, aspect, and hydrography maps were used to evaluate morphometric and hydrographic conditions. The district is predominantly characterized by gently sloping plains (0–6°) that are favorable for settlement and agriculture. However, steeper slopes in the western and southwestern regions present risks of erosion, landslides, and slope instability. The dense river network, including the Gargarchay and Khachinchay, enhances agricultural potential but contributes to flood and seasonal runoff hazards. The findings indicate that the engineering–geological conditions of the Aghdam district are heterogeneous, with zones of moderate suitability (dpQIV and gravelly apQII deposits) and zones requiring special geotechnical precautions (clayey apQII deposits). This integrated approach provides a reliable framework for evaluating geotechnical risks and supports sustainable planning, settlement, and infrastructure development in the region.