Malaysian Journal of Geosciences (MJG)

GEOPHYSICAL INVESTIGATION TO ESTIMATE THE CURIE POINT DEPTH, HEAT FLOW AND GEOTHERMAL GRADIENT IN SOKO AND ANKPA, BENUE TROUGH NIGERIA

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mjg.02.2020.64.67

ABSTRACT

GEOPHYSICAL INVESTIGATION TO ESTIMATE THE CURIE POINT DEPTH, HEAT FLOW AND GEOTHERMAL GRADIENT IN SOKO AND ANKPA, BENUE TROUGH NIGERIA

Journal: Malaysian Journal of Geosciences (MJG)
Author: J. A. Yakubu, J. C. Agbedo, N.M. Ossai

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.02.2020.64.67

This work presents the interpretation of the aeromagnetic data over Soko and Ankpa area using spectral analysis method. The study area was divided into eight (8) equal spectral blocks in order to estimate the depth to the top boundary, centroid, Curie point depth, heat flow and geothermal gradient of the study area. The result of the analysis shows the range of the depths to the top boundary and centroid varies between 1.085 to 1.984 km and 6.151 to 8.730 km respectively. The Curie temperature isotherm ranges between 11.112 km and 15.476 km and the geothermal gradients associated with it ranges from 39.967 and 52.196 0 𝐶⁄𝑘𝑚. The corresponding values of heat flow ranges from 93.697 𝑚𝑊𝑚􀀀 and 130. 49􀀁 𝑚𝑊𝑚􀀀. From this analysis, it was observed that areas with high geothermal gradient correspond to high heat flow and an inverse relationship exists between the heat flow and the Curie point depth. With the high geothermal gradient especially at the southeastern part of the study area, there is a possibility of enough geothermal energy for exploration in order to boost and generate clean energy for electricity.
Pages 64-67
Year 2019
Issue 2
Volume 4

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mjg.02.2020.57.63

ABSTRACT

PETROPHYSICAL EVALUATION OF RESERVOIRS FOR HYDROCARBON RESERVE ESTIMATION IN EASTERN CENTRAL SWAMP DEPOBELT, NIGER DELTA

Journal: Malaysian Journal of Geosciences (MJG)
Author: Omigie J.I., Alaminiokuma G.I.

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.02.2020.57.63

Petrophysical properties were evaluated in five wells in eastern Central Swamp Depobelt, Niger Delta using well logs. Analyses by Kingdom Suite software reveal that reservoirs’ thicknesses ranged between 24.5ft in SNG in Afam 16 to 200.5ft in SNB in Obeakpu 005. Volume of shale varies within and across all the wells with values <30% of the total thicknesses. Relative permeability to water (Krw) ranges from 0.00 to >1.00 across the wells. Reservoirs SNE and SNF in Afam 16 have average Krw of 0.00 implying 100% water-free hydrocarbon production. SNC reservoir in Afam 15 and Afam 16 has average Krw >1 implying 100% water production. The relative permeability to oil (Kro) is very high in reservoirs with high hydrocarbon saturation. SNH in Korokoro 006 has average hydrocarbon saturation of 85.70% and Kro of 0.89. SNB in Obeakpu 005 has average absolute permeability of 62,086.9mD. Reservoirs SNB, SNC and SND contain no producible hydrocarbon in Afam 15 but contain producible hydrocarbon in Afam 16, Korokoro 003 and Obeakpu 005 wells. Reservoirs SNE, SNF, SNG and SNH in Afam 15, Afam 16, Korokoro 003 and Korokoro 006 contain producible hydrocarbon with the exception of SNF in Korokoro 003. Afam 15 and Afam 16 are mainly gas-producing with estimated gas-in-place ranging from 72,630.27cu.ft/acre in SNB in Afam 15 to 1,534,667.86cu.ft/acre in SNH in Afam 16 while Korokoro 003, Korokoro 006 and Obeakpu 005 are mainly oil-producing with estimated oil-in-place ranging from 47,590.26bbl/acre in SNB in Korokoro 003 and 387,754.83bbl/acre in SNB in Obeakpu 005.
Pages 57-63
Year 2019
Issue 2
Volume 4

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mjg.02.2020.48.56

ABSTRACT

ASSESSMENT OF SOIL EROSION BY RUSLE MODEL USING GIS: A CASE STUDY OF CHEMORAH BASIN, ALGERIA

Journal: Malaysian Journal of Geosciences (MJG)
Author: Khanchoul K., Balla F., and Othmani O.

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.02.2020.48.56

Soil erosion by water is one of the major sources of land degradation. Erosion contributes to the temporary or permanent lowering of the productive capacity of agricultural land and sedimentation of dams. The purpose of this study is to assess soil loss rate using a GIS/RUSLE approach at the Chemorah basin by focusing on two catchments, namely, Reboa and Soultez. The assessment of soil erosion aims thus to identify the lands more prone to erosion which are vital for erosion management process. RUSLE model supported by GIS software is to predict the spatial variability of erosion occurring in the Chemorah basin and its sub-basins. Five inputs such as rainfall erosivity, soil erodibility, slope and length of slope, plant cover and anti-erosion practices, are used in the model to compute the erosion loss rates. The mean annual soil loss in Chemorah river basin is estimated at 7.52 T/ha/year, and varying between 3.78 T/ha/year in Soultez catchment and 6.06 T/ha/year in Reboa sub-basin. The study shows that low erosion (≤ 7 T/ha/year) covers 52% and high to very high erosion (> 7 T/ha/year) which does not exceed 23% of the Chemorah basin area. The results indicate that Reboa catchment faces the greatest risk of soil erosion compared to Soultez one, with contributions of 44 % and 32 % of their basin areas respectively. Use of the erosion factors’ information coupled with GIS/RUSLE program can help to design the appropriate land management to minimize soil erosion in the basin.
Pages 48-56
Year 2019
Issue 2
Volume 4

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mjg.02.2020.43.47

ABSTRACT

HYDROGEOPHYSICAL INVESTIGATION FOR GROUNDWATER RESOURCE POTENTIAL IN MASAGAMU, MAGAMA AREA, FRACTURED BASEMENT COMPLEX, NORTH-CENTRAL NIGERIA

Journal: Malaysian Journal of Geosciences (MJG)
Author: Chaanda M.S. Alaminiokuma G.I.

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.02.2020.43.47

Vertical Electrical Sounding (VES) was conducted in Salbi farm in the fractured Basement Complex, North- Central Nigeria to determine the groundwater resource potential to serve for agricultural purposes. Four VES stations using Schlumberger electrode configuration with a maximum current electrode spread of 300m were employed for data acquisition. ZHODY software was employed in computing resistivities, depths and thicknesses of the various layers and curve types. Results indicate that the area is characterized by 3 distinct geoelectric layers inferred differently at the VES locations. One potential groundwater aquifer zone was delineated at VES 1, 2, and 4 within the fractured/weathered basement columns having depths ranging between 48.8 – 59.60m and resistivities ranging between 213 – 513 Ωm. These results suggest that boreholes for sustainable groundwater supply in Salbi farm should be sited either at VES 1, 2 or 4 location and screened at a depth ≥60.0m. Wells to develop this resource should be drilled to an effective depth of 40 to 60 m for optimum yields. It is recommended that pumping test be done in order to further determine the aquifer efficiency and productivity in the area. However, the aquifers at these locations have potentials for groundwater but may be vulnerable to contamination.
Pages 43-47
Year 2019
Issue 2
Volume 4

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mjg.02.2020.37.42

ABSTRACT

MOBILITY AND REDISTRIBUTION OF MAJOR ELEMENTS IN WEATHERED PROFILE DEVELOPED ON PEGMATITE AT KITIBI-IWOYE, SOUTHWESTERN NIGERIA

Journal: Malaysian Journal of Geosciences (MJG)
Author: Jimoh, M.T., Bolarinwa, A.T, T. O. Kolawole

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.02.2020.37.42

Geochemical studies of weathering profiles around Kitibi-Iwoye revealed redistribution of elements from parental pegmatite to the regolith. Geological mapping showed that the pegmatite intrudes diorite and migmatite gneiss. Weathered samples from B-horizon were air-dried, pulverised and analysed using X-ray Fluorescence Spectrometry (XRF) in the Department of Geological Sciences, University of Cape Town, South Africa. Chemical Index of Alteration (CIA), Weathering Index of Parker (WIP), Mass balance calculation and Al2O3 – CaO+Na2O – K2O (A–CN–K) ternary plot were employed to determine elemental mobility and distribution caused by weathering. SiO₂ (74.2 and 43.4 wt %), CaO (0.43 and 0.03 wt. %), Na2O (7.14 and 0.04 wt. %), K2O (1.90 and 0.67 wt. %), MnO (0.11 and 0.03 wt. %) and P2O5 (0.20 and 0.05wt. %) displayed depletion from parent rock to the regolith respectively. But Al₂O₃ (15.5 wt. % and 33.5 wt. %), Fe2O3 (0.39 and 3.40 wt. %), TiO2 (0.04 and 0.35 wt. %) and MgO (0.08 and 0.11 wt. %) showed enrichment from parent rock to the regolith respectively. Fe₂O₃ (3.19) is the most enriched whereas Na2O (-99.8), CaO (-98.9), P2O5 (-95.3), K2O (-89.5), SiO2 (-81.9), MgO (-73.1), MnO (-64.5) and Al2O3 (-23.6) are progressively depleted. Mean CIA value of 97.8 revealed that weathering has almost reached its completion whereas CIA of 62.1 for the pegmatite suggested that the parent rock is at incipient stage of weathering. Pegmatite had a WIP of 110.5 whereas the weathered samples with WIP ranging from 2.66, 3.88, 6.03, 6.23, 6.92, 8.08, 9.08, 9.76 and 14.6 respectively showed decreasing trend of weathering. This study confirmed contrasting behaviour of CIA and WIP. A-CN-K diagram suggested strongly weathered samples plotted at the apex of Al2O3 field whereas pegmatite plots along the A-CN line.
Pages 37-42
Year 2019
Issue 2
Volume 4

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mjg.02.2020.32.36

ABSTRACT

THE EFFECT OF DENSITY-VELOCITY RELATION PARAMETERS ON DENSITY CURVES IN TAU (τ) FIELD, NIGER DELTA BASIN

Journal: Malaysian Journal of Geosciences (MJG)
Author: Atat, J. G., Akankpo, A. O., Umoren, E. B., Horsfall, O. I., Ekpo, S. S

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.02.2020.32.36

We considered the constants obtained for tau (𝜏)Field in the Niger Delta basin from well-log data of three wells (A,B,C) to investigate the effect of inclusion of these constants on density-velocity relation using Hampson Russell Software to generate density curve in tau field. The curves were compared to those generated from Gardner and Lindseth constants and in-situ density curves. Many researchers have worked on constants for density-velocity equations for different Fields; their results always differ from Gardner and Lindseth constants including the constants of Atat et al., 2020 which are considered in this investigation as Tau Field local fit constants. Our findings support the results of these researchers. Results indicate over estimation of density curves when using Gardner and Lindseth constants. The challenge is that in-situ density curves are not accurate due to sand-shale overlap of density values. The most improved and accurate result is given by the density curves obtained using the constants for specific sand and shale lithologies (local fits). This verifies the need for the determination of constants for local fit of the oil field under investigation. The pink curves truly indicate the density estimation for the tau field which is very reliable in the characterisation of reservoir.
Pages 32-36
Year 2019
Issue 2
Volume 4

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mjg.02.2020.32.35

ABSTRACT

GEOLOGICAL RECONCILIATION STUDY: ESTIMATED REMAINING OVERBURDEN MATERIAL AND RESERVE AT SIBANYIS QUARRY, KUCHING, SARAWAK

Journal: Malaysian Journal of Geosciences (MJG)
Author: Jong E Cheng, Rodeano Roslee

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.01.2020.32.35

This study presents the estimated remaining quantity of overburden material (topsoil, completely to highly weathered rock) and remaining geological reserve at Sibanyis Quarry, Kuching after the quarry has been operated for years. Desktop study including literature search was carried out prior field investigation. Three boreholes together with latest topographical and detail survey was conducted to obtain the latest data at Sibanyis Quarry, Kuching. Based on this Geological Reconciliation Study, the estimated total remaining geological rock reserve is 40,022,767 metric tons, and the weathered rock and top soil are 2,159,688 BCM and 1,247,697 BCM respectively. The assumptions that are taken into consideration are top soil thickness of 11m, weathered rock thickness of 15m and rock density of 2.64 mt/m3.
Pages 32-35
Year 2019
Issue 2
Volume 4

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mjg.01.2020.26.31

ABSTRACT

GEOLOGICAL ASSISTED ON WATER RESOURCES PLANNING IN MOUNTAINOUS CATCHMENTS IN KUNDASANG, SABAH, MALAYSIA

Journal: Malaysian Journal of Geosciences (MJG)
Author: Rodeano Roslee

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.01.2020.26.31

Based on geological mapping and geohydrologic data, water resources planning in mountainous catchment areas in Kundasang are outlined. The area is underlain by thick Paleogene clastic sediment and old Quaternary gravels. These rock units are carved by numerous lineaments with complex structural styles developed during series of regional Tertiary tectonic activities. The tectonic complexities reduced the physical and mechanical properties of the rock units and produced intensive displacements and discontinuities among the strata, resulting in high degree of weathering process and instability. The weathered materials are unstable and may cause subsidence and sliding induced by high pore pressure subjected by both shallow and deep hydrodynamic processes. Evaluation of 60 boreholes data in the study area reveals that the depth of the groundwater table ranges from 1.90 m (6 feet) to 11.20 m (35 feet) deep. The groundwater level in the study area fluctuates even within a short period of any instability of climatic change. The Quaternary sand and gravel layers with variable thickness defined the major shallow aquifers within the underlying weathered materials while the highly fractured sedimentary rocks defined the major deep aquifers. Most of the aquifers within the top unconsolidated weathered clastic material are under unconfined condition. The sedimentary formations are coarse-grained clastic materials generally contain fractured porosity and exhibit higher permeability. However, below subsurface, much of the groundwater is partially confined. Movements of groundwater are sufficiently restricted area to cause slightly different in head depth zones during periods of heavy pumping. During periods of less draught, the various groundwater levels will be recovered to their respective original level. This condition resulted from discontinuous nature of sediments where zones of permeable sand and gravel are layered between less permeable beds of silt and clay. Aquifer characterization and geological data are given to assist the local agencies on the water resources planning of the study area.
Pages 26-31
Year 2019
Issue 1
Volume 4

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mjg.01.2020.22.25

ABSTRACT

TUNNEL SUPPORT BY ROCK QUALITY INDEX (Q) SYSTEM FOR ULTRABASIC ROCK: A CASE STUDY IN TELUPID, SABAH, MALAYSIA

Journal: Malaysian Journal of Geosciences (MJG)
Author: Ismail Abd Rahim, Mohamad Saiful Nizam Mohamad

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.01.2020.22.25

The study area is underlain by the ultrabasic rock of partly Sabah Ophiolite Complex of Cretaceous ages. The objectives of this study are to determine the Q-value and to estimate the permanent support measures for 20m span, 10m high and eastern direction of the proposed tunnel in the study area. Engineering geological mapping (lithological and surface mapping and discontinuity survey), laboratory study (petrographical study) and testing (Uniaxial Compressive Strength testing) and data analysis (stereographic plots, Q system parameters evaluation and support estimation) was used in this study. The results show that the rock mass is classified as lherzolite, strong, excellent quality, more than four joint sets, slightly altered discontinuity wall, dry excavation and favourable stress condition. The equivalence dimension (De) are 15.4 for the permanent roof. The Q-value for permanent roof and wall of the proposed tunnel are 1.4 (Class D or poor and type 5) and 3.5 (Class D or poor and type 3), respectively. The permanent and temporary supports for the roof and wall are systematic bolting, 700J energy absorption of fiber reinforce sprayed concrete, 9-12 and 5- 6 cm thick fiber reinforce shotcrete, respectively.
Pages 22-25
Year 2019
Issue 1
Volume 4

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mjg.01.2020.19.21

ABSTRACT

THE ECONOMIC IMPACTS OF REHABILITATION OF SELABAT MUDFLATS NATURE RESERVE, KUCHING, SARAWAK

Journal: Malaysian Journal of Geosciences (MJG)
Author: Mukrimah Abdullah, Mohd Parid Mamat, Abang Ahmad Abang Morni, Thanlany Kamri, Lim Hin Fui

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/mjg.01.2020.19.21

Coastal erosion is a concern to coastline management, and it affects the socio-economic well-being of local communities. The rehabilitation of Selabat Mudflats Nature Reserve (SMNR) in Sarawak is one of the most impressive achievements of the “Mangrove and Suitable Tree Species Planting at the National Coastline Program” implemented by the Ministry of Natural Resources and Environment (NRE). The rehabilitation efforts began in 2009, where 20 hectares of Rhizophora mucronata were planted and followed by an additional 1.7 hectares of Casuarina equisetifolia. Previously, this area was a sandy coastline where coastal erosion occurred every year causing local loss of land and properties. However, through conservation and rehabilitation efforts, this area was restored and is now able to generate more income for local communities as well as playing a protective role against coastal erosion caused by coastal waves and strong winds. In 2016, this study was conducted to assess the economic impacts of SMNR rehabilitation. The findings from a sample of 42 households showed that the income generated for local communities around SMNR amounted to RM250, 320 per month or RM3, 003,840 per year. A non-user survey of 401 samples was also conducted, using Contingent Valuation Method to estimate the economic value of SMNR rehabilitation. The result showed the economic value of rehabilitation of SMNR was RM39 million for the year 2016 or RM195, 980 per hectare. These findings showed that the function of rehabilitation and conservation of mangroves forests against coastal erosion brings positive economic impacts. Rehabilitation and conservation of mangrove areas in Malaysia should be given more attention as global warming and rising sea level are going to have negative impacts on coastal settlements. Wise decision-making in the utilisation and allocation of limited resources is important particularly in the context of conflict between conservation and other development that led to its destruction.
Pages 19-21
Year 2019
Issue 1
Volume 4

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