Geological Behavior (GBR)

Interpretation of Aeromagnetic and Radiometric Data covering the basement region of Benue-Niger confluence was executed to delineate major structures and other geologic frame works of mineral interest. The study area which hosts the Benue-Niger confluence also encloses two major geologic units which are basement complex and sedimentary basins. The Aeromagnetic data set comprising sheet 227 (Koton-Karfe), 247 (Lokoja) and 267 (Idah) was enhanced to reveal geologic structures while radiometric data was analysed to map lithology and zones affected by hydrothermal alterations. A set of mathematical algorithms was used to enhance the data for interpretation. First Vertical derivatives, Analytical Signal and Euler deconvolution filters were applied to the Aeromagnetic data while Ratio and Ternary images of the three radiogenic elements were obtained for the radiometric data. Magnetic signatures from the TMI showed a mixture of high and low susceptibility below koton-karfe due to intrusion of oolitic iron ore within the sedimentary formation. Lokoja regions recorded highest susceptibility of 165 nT due to magnetic signatures emanating from exposed basement rocks. The southern Idah regions recorded relatively low susceptibility. Result of First Vertical Derivative revealed near surface mineral potent structures labelled F1 – F8, cringing surface features B1, B2 and B3. Analytical signal revealed high amplitudes range of 0.174 to 0.579 cycles for magnetic sources majorly at the basement regions, while low amplitude range of 0.021 to 0.157 cycles were recorded around the sedimentary regions. Euler depth analysis revealed shallower depth to sources in the basement and deeper depth to sources in the sedimentary regions due to thick overburden. Radiometric signatures from the K/Th ratio map revealed portions around Latitude 8°00’ NW and 7°30’ SW shaded in pink colour and having values above known threshold of 0.2 %/ppm to be hydrothermally altered. Mapping of lithology from Ternary map revealed K-Feldspar mineral bearing rocks dominated the NW and SW regions, while sandstones, ironstones, mudstones, shale, alluvium and other fluvial sedimentary lithologies dominated the sedimentary North-east and South-Eastern regions. The western regions (NW and SW) hosted the major structures in form of magnetic lineaments trending NE-SW and E-W which also coincided with regions delineated to be hydrothermally altered and apparently represents the most prospective regions of mineralisation in the study area.

The Mentawai Megathrust is predicted to cause a tsunami with the tremendous effects to societies and environments. As the coastal area located across the epicenter, Padang City is expected to have a high vulnerability to be surged by this future hazard. This issue has gradually grown in importance to provide an effective disaster countermeasure for minimizing losses and suffering. As the fuel is one of the most critical items required in the aftermath of disaster, this study seeks to propose the disaster relief planning in Padang City, particularly in the fuel location-allocation decisions to cope with the effects caused by the probable tsunami. In this research the Geographic Information System (GIS)-based optimization is utilized to generate the appropriate number of facilities as well as its allocated capacity to serve several demand points (e.g. hospitals and refugee camps) during the emergency periods. This paper initially considers the potential inundation area based on the worst-case scenario developed by the disaster countermeasure agency to identify the likelihood of the impassable paths and the candidate facilities in the safe zone. By using P-Median analysis, this work recommends 9 strategic facilities to handle 18 demand points during the critical periods. This study provides an exciting opportunity to comprehensively obtain the suitable facilities in order to fulfill the fuel needs in the disaster aftermath. Due to practical constraints, this paper may be further improved to be Decisions Support Systems (DSS) with the consideration to the real time conditions during emergency periods.

The subsurface structures in KOCR Field, in the Coastal Swamp Niger Delta, Nigeria, are here presented, using seismic 3D timelapse. The KOCR Field lies on latitudes 4o50’58’’-4o55’19’’N and longitudes 6o18’41’’- 6o26’41’’E with aerial extent of 840km2. The base (1997) and the monitor (2009) seismic surveys resulted in a 4D response difference. The Base and Monitor data have a root-mean-square repeatability ratio (RRR) of 0.38 implying a very good repeatability when considering the acquisition, processing and environmental noises. Data processing and interpretation were carried out using Petrel software. The average thickness of the reservoir is about 69m at the depth of 3932m. Reservoir pressure decline rate of 0.062psi/day resulted in production decline rate of 1192.21bbl/day. Structural interpretation of seismic data reveals a highly-faulted field. Fault and horizon interpretation shows closures that are collapsed crestal structures. All the interpreted faults are normal synthetic and antithetic faults which are common in the Niger Delta basin. The lengths, dips and orientations of the faults and horizons, in the base and monitor stacks, are equal indicative of no faults reactivation that could have resulted from hydrocarbon production. The results of this work can be used in reservoir, field and environmental management in the area of study.

Three-dimensional (3D) land seismic datasets were acquired from Central Depobelt in the Niger Delta region, Nigeria, with with the aim of attenuating ground roll noise from the dataset. The Omega (Schlumberger) software 2018 version was used along with frequency offset coherent noise suppression (FXCNS) and Anomalous Amplitude Attenuation (AAA) algorithms for ground roll attenuation. From the results obtained, Frequency Offset Coherent Noise Suppression (FXCNS) attenuates ground roll while AAA algorithm attenuates the residual high amplitude noise from the seismic data. Average frequency of the ground roll in the seismic data is 10.50Hz which falls within the actual range of ground roll frequency which is within the range of 3.00 – 18.00Hz. The average velocity of the ground roll in the seismic data is 477.36ms-1 while the velocity of ground roll ranges between 347.44 and 677.37ms-1. The wavelength of ground roll in the seismic data is 50.28m. The amplitude of the ground roll of -6.24dB is maximum at 4.2Hz. Frequency of signal ranges between 10.21 and 25.12Hz with an average of 17.67Hz. Signal amplitude of -8.32dB is maximum at 6.30Hz, while its wavelength is 57.12m. The results of this work can be used in the seismic source-receiver design for application in the area of study. Moreover, with ground roll noise attenuated, a better image of the subsurface geology is obtained hence reducing the risk of obtaining a wild cat drilling.

The novel coronavirus disease (COVID-19) has already changed the world in many respects, and its impact cuts across many fields of human endeavours. An area of temporary setbacks in geomorphological research posed by the pandemic is in the restriction placed on fieldwork exercise. Apart from bringing a lot of constraints to fieldwork, the need to meet the learning outcomes ensured that the already in-use technologies were easily adapted to simulate the necessary fieldwork in evaluating dynamics in geomorphological environment and the natural world. Despite the success, however, the fieldwork remains ‘signature pedagogy’ for geography, geomorphology and any other Earth Science disciplines. The dynamic nature of landforms, the serendipity of on-site field training and exercises, the ability to have a first-hand experience of field phenomenon, etc. are some of the expected rewards that could not be simulated remotely. Hence, when COVID-19 pandemic is over, the aspects of fieldwork should not be jettisoned for the simulated alternatives embraced in the pandemic. The two should work hand-in-hand for the diverse fields of geomorphological research.

Geopark is an innovation of protection for geological, biological and cultural diversity. Protection implementation need strong and active participation from many stakeholders such as government, private, media, academically and, most importantly is local communities. Collaborative and cooperation between stakeholders need to begin from the early of planning, implementation, monitoring and evaluation. The pentahelix model, a five-party partnership can be applied as a model in the protection and maintenance of Geopark-Ciletuh, South-Sukabumi of West Java. The aim of the study is to identify stakeholders that are involved in the management of Geopark Ciletuh in Sukabumi. The study focuses on the interaction between the stakeholders identified in the management of the Ciletuh Geopark. The research is using descriptive method with qualitative approach and the data are collected from primary and secondary sources. The informants were purposively determined, based on consideration and goals connected with the focus of the research. The informants in the research is various parties connected with the effort of mapping the stakeholders in local community within the area of Ciletuh Geopark of Southern Sukabumi. The result show that the five-party partnership model (pentahelix) can be expanded and explored according to the needs of interested community groups on Geopark Ciletuh protection. Efforts to protect Geopark Ciletuh by involving various parties need to be implemented in harmony so it is expected also to generate the socio-economic conditions of local communities. Increasing local knowledge of the importance of Geopark Ciletuh protection can be implemented by increasing the income of the people as the number of tourists’ increases.

Plasma Analyzer (IAP) and Langmuir Probe (ISL) experiments of the DEMETER microsatellite were used to check the state of the ionosphere in the region of the M8.1 East of Kuril Islands earthquake of 13th January, 2007,30 days afore and 10 days after the event using statistical approach. The study strongly revealed that all three investigated ionospheric parameters of electron density, total ion density and electron temperature displayed unfamiliar ionospheric variations eight days before the earthquake in the daytime time half orbit measurement. To this, the electron density, total ion density and electron temperature recorded a variation of 4.09, 5.73 and -2.03 respectively. These irregularities were vetted for untrue signals using the geomagnetic indices of Kp and Dst. It was however realized that the state of the ionosphere was geomagnetically quiet during this day, hence the observed variations were seismogenic.

In this appraisal, heavy metal concentrations in soils from Zamfara State were enumerated approximately a decade after the lead poisoning saga using indexes of pollution. The area is enhancement with valuable ores and minerals including gold making mining the most lucrative business in the area. The soils were moderate to slightly basic with a pH range from 6.49 ± 0.12 to 7.96 ± 0.15 (water) and 6.15 ± 0.10 to 7.80 ± 0.17 (KCl). Contamination / pollution (C/P) values reported for cadmium, lead, zinc and copper was 42.66, 0.59, 0.85 and 3.04 in the respective order (severe contamination to excessive pollution). The contamination factor (CF) was greater than the highest factor of 6, indicating very high contamination. The calculated values for geochemical accumulation (Igeo) and ecological risk factor (ERf) for Cd, Pb, Zn and Cu was (19.26, 0.27, 0.38, 1.37) and (1280, 2.95, 0.85, 15.2) respectively while the potential ecological risk index (ERi) was 1299, indicating that the soils were perturbed (polluted). Considering the deleterious effects heavy metals could cause and the resultant health implications, there is need to further remediate the polluted areas so as to avert harm to organisms and humans would consume crops grown in such environment.

Seismic refraction survey was conducted at Ibiono Ibom Local government area of Akwa Ibom State, Nigeria, using 12 channels ES 3000S enhancement seismograph. This was done to evaluate and obtained information on depth and thickness of the shallow subsurface and characterized the bearing and engineering parameters on the bases of soil and rock competencies for stability of engineering works. The travel times of refracted waves measured were used to calculate P and S wave velocities employed in the evaluation of bearing strength and engineering parameters. The results revealed that seismic waves penetrated into three layers. The values of depth and thickness for upper layer ranged from 0.0 m to 4.5 m and 4.5 m, middle layer ranged from 5.0 m to 12.5 m and 7.5, lower layer ranged from 15.0 m to 25.2 m and 10.2 m. The bearing capacity parameters calculated were allowable bearing capacity and ultimate bearing capacity, engineering parameters: Concentration Index, Stress Ratio, Material Index and Density Gradient. The third layer reflected good competent soil and rock quality in the southeastern part of the study area, and was delineated as a better layer for engineering stability.

Geophysical study involving aeromagnetic method was carried out to investigate parts of Niger Delta in Nigeria, aimed at investigating the cause and nature of anomalous bodies within the study area. Spectral analysis technique was employed in quantitative interpretation to determine depth/thickness of the sedimentary basin, basement topography, structural trends, curie point depth, thermal gradient and heat flow in the area. The total magnetic intensity (TMI) anomalies had values of between -53.7nT and 119.5nT while the residual magnetic intensity ranged from -52.5 to 58.0nT. The spectral analysis revealed the depth to magnetic sources varying from 2.5 to 5.5km while the shallow magnetic sources varied from 0.89 to 1.47km. The geothermal analysis revealed the curie point depth between 11.782 and 18.048km while the calculated geothermal gradient ranged lie between 32.137 and 49.231o𝐶𝑘𝑚−1. The heat flow values ranged from 80.343 to 123.080𝑚𝑊𝑚−2. The results from this study have thrown more light to the understanding of the variation of subsurface structures in the study area. These will enhance the development of the resources and will be of economic benefit to the country if well harnessed. However, possible future research work on this active area is proposed for more robust results.