Subsurface Lithostratigraphic Characterization Using Integrated Log and Cross-Plot Analysis: Re-evaluation of a Borehole in Chirirbandar, Dinajpur, Bangladesh
Aug 2026· Earth Sciences· Vol 15, pp. 193-204· 0 citations
Abstract
This research represents a detailed Litho-stratigraphic characterization of Precambrian basement complex by integrating geophysical log and drilling data of GDH-76 from technical reports of the Geological Survey of Bangladesh (GSB). It is a re-evaluation of a Borehole data by interpreting drilling parameter and interval-averaged geophysical log data. A high-resolution petro-physical “fingerprint” of the Northwestern Bangladesh basement complex is identified by integrated cross-plot analysis. This study delineates a six subsurface zones by correlated Rate of Penetration (ROP), Percentage of Core Recovery, Magnetic Susceptibility, Gamma-Resistivity signatures. The Result shows a distinct 6 meter weathered transition zone (200-206 m) characterized by low core recovery (45%) and moderate ROP (1.02 m/hr). The basement entry at 206 m is marked by moderate to high (0.46 to 1.1 m/hr) in ROP and moderate resistivity (72.5 ohm-m) indicating weathered condition. Notable feature include a 15-meter thick magnetic anomaly zone (295-310 m), identified with a peak susceptibility of 1130 cgs unit, suggesting a mineralization zone. Moreover, a high-gamma unit (318-336 m) exhibiting a value of 375 cps (peak value) with extremely low ROP (0.132 m/hr) indicates a high strength potassium-rich felsic lithology. Furthermore, the research also pinpointed the F39 fault boundary between two boreholes.
This study presents a multi-methodological approach combining subsurface characterization with dynamic structural assessment to evaluate Soil–Structure Interaction (SSI) mechanisms at the Palazzo Centrale. The 3D Electrical Resistivity Tomography (ERT) and active Multichannel Analysis of Surface Waves (MASW) results were compared with a lithostratigraphic core log to outline the subsurface framework. The stratigraphic framework mapped geotechnical heterogeneities within the upper 6.0 m, where a low-resistivity anomaly (≤1 log(Ω·m)) outlines a mechanically weakened, water-saturated cover deposit overlaying the basaltic lava. This characterization provides the physical baseline useful for interpreting the site response. In this framework, the ambient vibration recordings performed at the free-field sites exhibit a flat Horizontal-to-Vertical Spectral Ratio (HVSR) response within the 1.0–10.0 Hz range, whereas a localized stratigraphic peak emerges at higher frequencies near 15.0 Hz, particularly evident in the building’s courtyard. The building resonance frequency peaks, derived from the Horizontal-to-Horizontal Spectral Ratio (HHSR) analysis at 3.74 ± 0.09 Hz (NS) and 3.58 ± 0.22 Hz (EW), do not overlap with the site resonance frequencies, demonstrating a dynamic decoupling between the soil and the building within the low-to-medium frequency domain. Conversely, the secondary stratigraphic peak near 15.0 Hz overlaps with higher-order structural frequencies tracked in the HHSR datasets. Given the localized nature of this stratigraphic peak and the involvement of higher-order structural modes, this overlap suggests a limited, localized high-frequency amplification confined to specific architectural components, rather than a global site-structure hazard. Furthermore, torsional analysis reveals significant effects within the 3.8–4.0 Hz frequency band, targeting the North-East corner (peak value of 2.85 at station A4), indicating a localized dynamic anomaly due to structural heterogeneities. Overall, this multi-method approach proves highly effective for non-invasive structural diagnostics, establishing a rigorous physical reference that could be successfully integrated into future preventive conservation frameworks and routine monitoring protocols for ancient architectural heritage.
S. Imposa, Claudia Pirrotta, S. Grassi et al.· The Heritage· 0 citations
To address the growing challenges of water resource management in coastal karst areas, this study investigated subsurface lithological characteristics and evaluated aquifer potential in Mon Ikeun Village, Aceh Besar. The research integrated Electrical Resistivity Tomography (ERT) and grain size gradation analysis to provide a scientific basis for sustainable groundwater exploration. Resistivity data were collected along three survey lines, each 420 m long, using the Wenner-Schlumberger configuration. The 2D inversion results identified conductive zones with resistivity values below 454 Ωm, interpreted as alluvium comprising sand, silt, and gravel. These high-porosity, permeable layers extend to depths of approximately 25 m, indicating significant aquifer potential. In contrast, resistive zones above 454 Ωm were interpreted as limestone bedrock, representing impermeable layers with very low porosity. Laboratory grain size analysis using the hydrometer method revealed sand-dominated samples with high porosity (25-50%) and moderate permeability (2.5-45 m/day), while gravel-sand mixtures displayed moderate porosity (25-40%) and high permeability (150-450 m/day). The strong correlation between resistivity data and grain size distribution confirms the consistency of the lithological interpretation. This integrated approach offers an effective framework for securing freshwater resources in regions with complex geological settings and high vulnerability to water scarcity.
Muhammad Syukri, Adila Latifa, D. Sugiyanto et al.· IOP Conference Series: Earth...· 0 citations
Tunnel design in tropical regions requires careful attention to subsurface variability due to intense weathering and complex lithology. The ongoing design of the Jatinegara Diversion Tunnel, with a diameter of 6 meters and a length of 439 meters, relies solely on the 2024 borehole data without considering the recent 2017 data, revealing a contrast subsurface geological characteristic. This study investigates lateral lithological variations along the tunnel alignment by integrating surface geological mapping with multi-year borehole data from 2017 and 2024. The methodology includes geological mapping of a 2.0 × 2.0 km area, corebox analysis, surface-subsurface stratigraphic correlation, and rock mass quality evaluation using the Rock Mass Rating (RMR) system. Results show the tunnel traverses five zones with distinct rock mass characteristics. Zone 1, Zone 3, and Zone 5 consist of andesitic breccia with RMR values ranging from 20.21 – 39.57, indicating poor quality of rock mass. Zone 2 comprises interbedded carbonate sandstone and siltstone overlain by andesitic breccia, with RMR values ranging from 42.82 – 52.40 (fair). Zone 4 consists of interbedded carbonate sandstone and siltstone overlain by massive sandstone with siltstone intercalation with an RMR of 52.43 (fair). Given these rock mass conditions, the recommended excavation method is a top heading and bench approach with 1.0–1.5 meters advance in the top heading with support system consist of rock bolt, shotcrete, and steel set. These findings highlight the importance of integrating multi-year geotechnical data to support an adaptive and safe tunnel design in complex geological environments.
Eka Dhamayanti, H. Setiawan, S. Husein· IOP Conference Series: Earth...· 0 citations
Rapid urban expansion along Egypt’s northwestern Mediterranean coast requires reliable subsurface characterization capable of supporting both geotechnical safety and sustainable groundwater management. This study integrates 87 Electrical Resistivity Tomography (ERT) profiles with borehole logging data, including gamma ray (GR), spontaneous potential (SP), and granulometric analyses, to establish a high-resolution geotechnical and hydro-stratigraphic framework for the Ras El-Hekma coastal zone in Egypt. The integrated dataset resolved four principal subsurface units with distinct resistivity signatures, lithological compositions, and engineering characteristics, calibrated through co-located borehole logs and laboratory granulometric analyses. Statistical analyses revealed strong inverse relationships between resistivity and both porosity (r ≈ − 0.52; r ≈ − 0.85 for thickness-corrected values) and clay content (r ≈ − 0.78; 95% CI (− 0.85, − 0.69)), while GR values showed a strong positive correlation with clay percentage (r ≈ 0.95; p < 0.001). The third geoelectrical layer, dominated by clay-rich Pliocene shale, represents the most problematic geotechnical unit, characterized by resistivity values below 12 Ω·m, clay content exceeding 34%, and thicknesses ranging from approximately 1.5 to 3.5 m. Spatial analysis demonstrates marked NE–SW heterogeneity associated with buried oolitic ridges, sabkha environments, and localized saline intrusion. Based on integrated petrophysical signatures, the study area was classified into four competency zones (A–D), each linked to specific foundation and ground-improvement recommendations. The proposed workflow provides a transferable, cost-effective framework for coastal arid regions by combining geophysical imaging, borehole calibration, and statistical interpretation to support sustainable urban planning, infrastructure development, and subsurface risk assessment.
Raghda M. Abd Elhamid, A. Basheer, M.S. Toni et al.· Scientific Reports· 0 citations
Abstract A geothermal potential assessment was conducted in the Suban Curup–Rejang Lebong Hot Spring Area, Bengkulu Province, Indonesia. This study aimed to identify subsurface geological structures—faults, volcanic features, and sedimentary layering—that may control the development of geothermal reservoirs and caprock units. Two complementary geophysical approaches were integrated: (1) Three-dimensional (3-D) inversion modeling of Bouguer gravity anomalies derived from Global Gravity Model plus (GGMplus) 2013 and corrected using SRTM2gravity at 1,937 measurement points, and (2) microtremor acquisition at 106 sites with 60-minute recording duration, processed using the Horizontal-to-Vertical Spectral Ratio (HVSR) method. The residual gravity inversion results reveal density contrasts of 2.40–3.40 g/cm3 and sediment thicknesses exceeding 80 m, interpreted as potential geothermal reservoir units. These findings are consistent with the HVSR results, which show moderate to high amplification (A0 = 3–9) and natural frequencies of 1–10 Hz, indicating porous and fractured formations favorable for fluid storage. Overall, the integration of satellite gravity and microtremor data highlights the presence of thick sedimentary deposits and structurally controlled pathways, suggestive of promising geothermal reservoir targets in the Suban Curup area.
P. K. Putri, Ahmad Fauzi Pohan, A. M. Lubis et al.· Civil and Environmental Engi...· 0 citations
In the Nepalese and Indian Terai Arc Landscape (TAL), protected nature areas are supported by groundwater systems that have remained largely understudied. This study schematizes the lithology of the Karnali fluvial fan located in the Bardia district (Nepal) as a basis for future hydrogeological investigations. Inversion results of 2D electrical resistivity tomography (ERT) profiles at 21 locations were interpreted by comparing with the local borehole lithology and regional geophysical studies. Multiple lithological cross-sections were prepared to develop a 3D lithological model spanning the fan, and the adjacent Bardia National Park up to the Babai River in the east. Sediment resistivities found were in the range of 8–6000 Ω m. Resistivity less than 40 Ω m was identified as clay, 40–80 Ω m represented silt and fine sand, 80–400 Ω m identified as fine to coarse sand and resistivities higher than 400 Ω m were interpreted as coarse sand, gravel and boulders. A coarse sand-gravelly layer is present at the fan apex and along the foot of the Himalayas in the north that functions as a recharge area and aquifer. The central part of the fan has sandy layers which transition to fine sand and silt layers in the distal south and southeast. Clay layers locally create confining conditions, within the sand and silt dominated areas. These findings on subsurface lithology provide valuable insights for the groundwater systems which sustain ecohydrological processes relevant to the protected ecosystem and fills a critical knowledge gap on regional hydrogeology of the TAL.
Mayuri Phukan, P. Schot, M. Rijal et al.· Hydrogeology Journal· 0 citations