Geological Behavior (GBR)

The usefulness of groundwater vulnerability mapping cannot be overemphasized in planning, policy formulation and decision-making for groundwater management and protection. The present study employed geographic information system based overlay and index methods (DRASTIC, DRASTIC-LU, GOD and AVI models) in assessing and mapping groundwater vulnerability zones in Ile Oluji area of Ondo State, Southwestern Nigeria. The models’ parameters were prepared using hydrogeological (well/borehole) data, geophysical data, and satellite imageries. The weightage of different parameters was done using analytical hierarchy process. The DRASTIC map classified the area into the low vulnerability (30 % of the area), moderate (4%), high-vulnerability zone (60 %), and very high vulnerability zone (6 %). The DRASTIC-LU distinguished the area into high – very high groundwater vulnerability zone (90 %), while low – moderately low area has 10 % aerial extent. The GOD and AVI models, categorized the vulnerable areas into quite low (<0.03) to low (0.03 – 0.3); and high (0.98 – 1.85) to extremely high (<0.98) vulnerability zones respectively. As a result, the DRASTIC, DRASTIC-LU, and AVI models all showed predominate high vulnerability zone, which was also confirmed by the nitrate map. The index values in the DRASTIC and DRASTIC-LU models revealed significant overlap. Therefore, in the research region, slope, hydraulic conductivity, net recharge, soil medium, and depth to water level are the factors that have the greatest influence on groundwater quality. Due to the significant number of highly vulnerable places, the aquifers must be protected immediately.

The Banket Series, which is a paleoplacer deposit, is the third formation in the stratigraphy of Tarkwaian Supergroup. This project seeks to study petrographically; the lithologies in the banket series to confirm the rocks identity as already known or state otherwise. Two different photomicrographs of each of the rock samples, coupled by their petrographic descriptions were obtained from the laboratory. The main areas of our arguments were based in Bowen’s reaction series, metamorphic facies of the rocks, the earth structure and thermodynamic phase diagrams. The sampled rocks can be confirmed with the help of thin sections and mineral facies to be conglomerate, dolerite and quartzite. The minerals in the banket series range in temperature between 200°C and 800°C. The abundance of silica (SiO2) in the rocks conglomerate, dolerite and quartzite are of crustal origin, whereas pyroxene and olivine originate from the upper mantle. The common stable minerals in the studied rocks, namely, amphibole, chlorite and plagioclase are less likely to change compared to the other minerals in the rocks. The three (3) different metamorphic facies of the rocks conglomerate, dolerite and quartzite are respectively greenschist, epidote-amphibolite and amphibolite facies.

The Hawal Basement Complex is located in Nigeria’s NE region. Satellite imagery used in this study covers longitude 12º 00’ to 13º 30’E, and latitudes 9º 30’ to 11º 00’N. The aim of the study is to decipher the regional geologic structures based on analysis and to determine the mineralization implications from the landsat lineament data. The total land surface area covered is about 23,674.88 km2 and includes part of the north sector of Yola sedimentary Rift Basin. The data consists of LANDSAT TM and SPOT XS scenes collated as mosaics. The imagery was monoscopically studied. Classical aerial imagery interpretation techniques of mapping lineaments and tracing regional geological boundaries were used. A total of 368 lineaments were mapped and analyzed using multi-graphical analytical techniques. The results are presented as isolinear contour maps (isodensity and lineaments intersection maps). The isodensity lineament maps show two main areas of lineament concentrations, namely Shani area lying westward and Michika-Mubi area to the east. Reasons advanced for the preponderance of lineaments in parts of the study area are the combined effects of isostatic basement uplift and lithospheric stretching during the formation of Yola Rift and Chad Basin respectively, which caused large scale crustal deformations. Also, Precambrian and Cenozoic magmatic activities that caused emplacements of older granites and basaltic bodies respectively in the area contributed to fracturation of the crust. Fewer lineaments are observed over the sedimentary Rift zone and this is attributed to masking effect of the sediments on basement fractures. The lineament intersection map shows a prominent NE-SW zone of highest intersection which is parallel to the general flow direction of the Hawal River. Prominent lineament directions are N-S (0-20º), and NE-SW (40º- 60º), which are Pan African Orogenic directions. Aerogeological studies of this type are important in national economic development.

This study is focused on the interpretation of structural style in Wabi field in the Niger Delta Nigeria using seismic and well log data. From the results, faults and horizons correlated on Wabi wells tied perfectly to reflections on the seismic. The faulting pattern shows that the structural geometry over the Wabi field consist of an elongated N-W to S-E trending, collapsed crest, roll-over structure with two crests separated by a central saddle. Based on their lateral extent and throws Faults in Wabi Field is classified into boundary faults that confined the Wabi structure, synthetic and antithetic faults are within the crestal roll-over structure. The interplay of these faults, combined with the structural dip, provides the closure for the hydrocarbon accumulation within the field. Hydrocarbons in the field are encountered between 9,560 and 12,750ftss, and are contained within 3 stacked B, O, and R1 reservoirs in crestally collapsed rollover anticline. The reservoirs are predominantly shore face and are correlatable throughout the Field. Well correlation and sand analysis showed that sand R1 was the thickest sand unit by 320ft. Sand B is the thinnest sand unit in Wabi Field, it is 50ft. Results from this study provides interpretation and modelling of structural and stratigraphic interplays that would help in understanding of the feature and factors that control them reservoirs thereby creating room for predictive models that can be applied in other reservoirs at greater depth prospects. This helps to make informed decisions for optimum exploration and development of hydrocarbons in the field of study.

This paper seeks to assess the potential of Alkali-Silica Reaction on some granitic rocks in Kumasi in Ghana. Alkali-Silica reactions occur over time between alkaline cement paste and silica contained in rock aggregates as a result of the swelling due to the reaction of certain constituents in the rock aggregates with alkali hydroxides. Alkali-Silica reactions become potentially harmful when they cause significant expansion. Aggregates used for this research were sought from three different quarries, namely, Consar Stone Quarry in Barekese, Nnagot Quarry in Kona and Modern Granite Quarry in Buoho. To achieve the objectives of this project, two test methods were employed such as Accelerated Mortar Bar test (ASTM C1260) and Petrographic analysis. Presence of strained quartz is an indicator for the occurrence of Alkali-Silica Reaction. Samples from Kona contained quite an appreciable amount of strained quartz and exhibited an expansion above the ASTM C 1260 specification, implying that it is potentially reactive and thus not useful for construction works, whilst samples from Barekese, and Buoho were innocuous and may be used for construction works. Supplementary cementing materials such as pozzolans (which are readily available) can be added to concrete mixtures with aggregates from Kona to reduce the harsh effects of ASR.

Sandstones are abundant in the regions of Azad Jammu and Kashmir in northeastern Pakistan. However, physio-mechanical data for project planning and construction of these sandstones, which serve as aggregates and foundations for a variety of infrastructures, are lacking. This research aims to investigate the petrographic and physio-mechanical characteristics of Murree and Kamlial Formation sandstones in the Rawalpindi group. The physio-mechanical parameters included specific gravity, water absorption, unconfined compressive strength (UCS), slake durability, Ultrasonic pulse velocity (UPV), and Brazilian. The findings suggest that the sandstone of the Murree and Kamlial formations can be classified as construction-grade rocks. A comprehensive analysis of physico-mechanical observations of these sandstones shows a statistically significant correlation with point load index, Brazilian tensile strength, and UPV in a saturated condition against unconfined compression strength (UCS). Whereas the specific gravity, water absorption, slake durability index, and UPV in dry conditions found no statistically significant correlation against UCS. By rigorous petrographic research, the texture of quartz %, mineralogy and mineral alteration, the existence of micro-fractures, and mineral size distribution all contribute to the total strength qualities of these sandstones. To comprehend the suitability of Muree and Kamlial Formation sandstones, physio-mechanical characteristics were then correlated with the sequence (Murree sandstone) exposed at the Jena Kor village in Peshawar Basin. Based on the results, the sandstones of the Murree and Kamlial Formations in the study area are found appropriate for construction.

This work is focused on the members of the Late Cretaceous-Early Paleogene (K-Pg) diagnostic benthic foraminiferal genus Orthokarstenia which is regionally important in paleontology and stratigraphic correlations. The large number of tests available and the rapid morphologic changes, offer an opportunity to study evolutionary changes in these foraminiferal taxa over a time span of about 25 m. y. (75-50 Ma). Six species of the genus Orthokarstenia are presented: O. applinae, O. eleganta, O. esnehensis, O. higazyi, O. nakkadyi and O. oveyi, which were recorded in eight localities in the Southern Tethys: Nigeria, Tunisia, Egypt (central and north Africa), Jordan, Saudi Arabia, UAE, Iran and Pakistan (southwest Asia). Evolutionary changes of them are indicated by such criteria, such as changes in the test-size, chambers arrangement, type of sutures, periphery or surface ornamentation. These changes help to define the major faunal change of the Campanian/Maastrichtian (C/M) boundary, K/Pg boundary, and can used in biostratigraphic subdivisions and correlations based on benthic foraminifera, beside planktic foraminiferal zonation.

Geodetic observations for both vertical and horizontal control networks cannot be compromised for any reason in accuracy and precision in the field of geomatics. Due to the error-prone nature of survey measurements, standards are established to allow for comparing the obtained results with a set of guidelines, regulations, or pre-determined specifications. The University of Benin’s Ugbowo Campus in Nigeria does not have enough control points, which informs this study. The densification of more reliable control points using the most recent technology is necessary. Before the observations, control network design, excavation, casting, and monumentation of first-order compliance beacons had been completed. Eight GNSS receivers were connected to the CORS_Geosystems multi-link access point and simultaneously deployed for observations. The stages involve the adjustment of observed data, the presentation of adjusted results, and the determination of horizontal and vertical accuracies. The result of horizontal accuracy showed that the RAPH_GNSS_08 station had the highest horizontal accuracy standard ratio of 1:432,193, while the Raph_GNSS_04 station had the lowest, 1:133,271. The highest vertical accuracy standard was 4.0mm, achieved between Cors_Geo and RAPH_GNSS_09, while the lowest, which was 3.1mm, was observed between Cors_Geo and RAPH_GNSS_08. High-precision engineering projects in the research area will benefit from the established first-order controls in terms of execution, monitoring, and maintenance. The Surveyors Council of Nigeria (SURCON) has recommended GNSS as one of the methods for achieving geodetic control densification in Nigeria.

Thirty three small diagnostic benthic foraminiferal species of the Textulariid genus Spiroplectinella are common in the Late Cretaceous-Neogene rocks from many Tethyan localities: North Atlantic (USA, Mexico, Caribbean), South America (Brazil, Argentina, Chile, Venezuela, Ecuador), Europe (North Sea, Norway, Spain, France, Poland, Czech, Italy, Hungary, Slovenia, Croatia, Romania, Bulgaria, Ukraine, Turkmenistan), North Africa (Tunisia, Egypt), Southwest Asia (Turkey, Jordan, Iraq, UAE, Iran, Pakistan) and Indian Ocean (Australia, Antarctic Basin). These diagnostic species are: Spiroplectinella adamsi, baudouiniana, carinata, chicoana, costata, cretosa, dalmatina, dentata, deperdita, desertorum, elongata, esnaensis, excolata, hamdani, henryi, israelski, jarvisi, knebeli, laevis, longa, nuttalli, paleocenica, paracarinata, pectinatiforma, plummerae, praelonga, richardi, rossae, semicomplanata, sigmoidina, subhaeringensis, wilcoxensis and wrightii. The paleontology, stratigraphy, paleoenvironment and paleogeographic distribution of them in the Tethys are presented.

The purpose of this research is to establish the relationship between the gold grades and the various pebble sizes from a mine. This objective was reached by choosing parameters of interest from the logging and sampling data, lithological data and assay data from the mine. These parameters were further processed using Microsoft Excel to plot graph of pebble size against gold grade. In order to build a concrete ground for the analysis, an average gold grade for the various samples used was calculated and compared to the cut-off grade at the Mine which is 0.45g/t. Upon further analysis, it was observed that, gold grade which are considered economically feasible at the mine is associated with the coarse pebbles, which has a diameter range of (5mm-30mm) and those which are considered as waste are associated with the fine pebbles (less than 5mm diameter). Some of these coarser pebbles are not economically feasible, since their average gold grade when calculated falls below the cut-off grade at the mine. The mode of deposition as well as the topography of the medium at the time of deposition of gold determine the gold grade of a reef. The degree of roundness and sorting of the conglomerates associated with mineralization as well as ore dilution within the depositional medium by the pebbly quartzite and quartzite waste account for the fall in gold grade of the reef.