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- Review books or articles provide a critical and constructive analysis of existing published literature in a field, through summary, analysis, and comparison, often identifying specific gaps or problems and providing recommendations for future research. These are considered as secondary literature since they generally do not present new data from the author's experimental work. Review articles can be of three types, broadly speaking: literature reviews, systematic reviews, and meta-analyses. It also the researcher to stay abreast of new literature in the field.
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Recent Submissions
Exploring Soil Pollution Patterns In Ghana’s Northeastern Mining Zone Using Machine Learning Models.
(Journal of Hazardous Materials Advances, 2024-09-22) Kwayisi, D.; Kazapoe, R.W.; Alidu, S.; Sagoe, S.D.; Umaru, A.O.; Amuah, E.E.Y.; Kpiebaya, P.
This study assessed the pollution status and effectiveness of machine learning models in predicting pollution
indices in soils from a mining area in Northeastern Ghana. 552 soil samples were analysed with an Energy
Dispersive X-ray Fluorescence (ED-XRF) spectrometer for their elemental concentrations. Four pollution indices;
Nemerow Integrated Pollution Index (NIPI), degree of contamination (Cdeg), modified degree of contamination
(mCdeg) and Pollution Load Index (PLI). Additionally, the Multivariate Adaptive Regression Splines (MARS)
machine learning approach were used. The high CV%, skewness, and kurtosis values show a high degree of
variability and uneven distribution patterns which denotes dispersed hotspots that can be interpreted as an
influence of gold anomalies and illegal mining activities in the area. V (120.86 mg/L), Cr (242.42 mg/L), Co
(30.92 mg/L) Ba (337.62 mg/L), and Zn (35.42 mg/L) recorded values higher than the global and regional
contaminant thresholds. The NIPI shows that 46.74% and 26.81% of samples are slightly and moderately
polluted respectively. The Cdeg analysis supports these findings, with 36.96% and 41.49% of samples classified
as having “moderate” to “considerable” contamination, respectively. The PLI indicates progressive soil quality
deterioration (43.84%) of samples reflecting substantial environmental disturbance. The pollution indices show
the effect of illegal mining on Shaega, Buin and other areas in the eastern boundary of the study. The MARS
models developed for the study demonstrated high predictive capabilities with an R2 value of 0.9665 for model 1
(NIPI), and RMSE and MAE values of 0.8227 and 0.4287 respectively. For model 2 (Cdeg), R2 value of 0.9863,
RMSE and MAE of 1.0416 and 0.6181, respectively. Model 3 (mCdeg) produced an R2 value of 0.9844, RMSE and
MAE of 0.1225 and 0.0670. These findings suggest MARS models can be an integral tool for soil quality analysis
in cooperation with pollution indices. The study suggests that remedial and legislative measures be implemented
to address the issue of illegal mining in the area.
Patterns And Source Apportionment Of Potentially Toxic Elements Distribution In The Soils Of The Nangodi Area, Northeast Ghana: A Multivariate And Machine Learning Approach.
(Journal of Hazardous Materials Advances, 2025-03-14) Kazapoe, R.W.; Kwayisi, D.; Alidu, S.; Fynn, O.F.; Sagoe, S.D.; et al.
This study assessed the sources, distribution and pollution status of heavy metals in the Nangodi area of Northwestern Ghana. Cr (120.86 mg/kg) and Co (30.92 mg/kg) had respective average values of 2.4 and 1.2 times
higher than their Continental Crustal Averages of 100 mg/kg and 25 mg/kg. The Potential Toxic Elements (PTE)
displayed a decreasing trend in the order Ba > Cr > V > Sr > Cu > Zn > Co > Mo. The Metal Index assessment
highlighted the significant effect of galamsey on the soil health of the area. The samples were ranked as slightly
(26.45 %), moderately (25.18 %), Strongly (21.20 %) and seriously (23.91 %) affected. The positive Matrix
Factorization identified three Factors as controlling PTEs in the area. Factor 1/anthropogenic (V = 84 %, Cu = 84
%, Co = 75.5 % and Zn = 58.9 %). Factor 2/geogenic (Ba = 87.5 %, Sr = 83.1 %, Pb = 57.8 %). Factor 3/mixed
source (Cr = 91.8 % and Mo = 43.4 %). The Pearson correlation matrix outlined two groups of PTEs; (1) PTEs
with moderate to strong correlation (V, Co, Cu and Zn) and (2) PTEs with weak to moderate correlation (Sr, Mo,
Ba and Pb). The first group occurs at the southwestern boundary of the study area, reflecting the influence of
local geology and mining practices on the levels of potentially toxic elements (PTEs) in the soil. The Self
Organising Map (SOM) identified three higher concentration clusters, V, Zn, Cu, and Co, inferred to be the
mining activities. Geogenic-sourced Sr and Ba are located centrally. Pb, Mo, and Cr show distinct distributions,
suggesting mixed factors affecting their spread. The study identified systematic heavy metal pollution, which
could pose a deleterious risk to the environment and inhabitants of the area.
Source-Specific Probabilistic Health Risk Assessment Of Potentially Toxic Elements In Soils From A Mining Area Using Monte Carlo Simulation: A Case Study From Southwestern Ghana.
(Ecological Indicators, 2025-04-11) Kazapoe, R.W.; Kwayisi, D.; Alidu, S.; Sagoe, S.D.; Amuah, E.E.Y.; et al.
This study evaluates the impact of mining on soil contamination by conducting a source-specific probabilistic
health risk assessment of Potentially Toxic Elements (PTEs) in Southwestern Ghana. Using an Energy-Dispersive
X-ray Fluorescence (ED-XRF) spectrometer, 720 soil samples were analyzed for their elemental concentrations.
The samples were obtained in 2024 from the B-horizon to provide better accuracy in detecting actual contam ination levels linked to illegal mining activities. The PTEs with the highest frequency above their Upper Con tinental Crustal Averages (UCC) were As(100 %), Ba(13 %), Cr(5.8 %), Pb(2.7 %), Co(2 %), V(2 %), Cu(0.4 %)
and Zn(0.4 %). Correlation Coefficient, Self-Organizing Maps (SOM) and Principal Component Analysis (PCA)
identified three groups of PTEs, which are geochemically linked elements (Ba, Cr, Cu, Ni, V), anthropogenically
influenced As, and a group with low correlations (Co, Pb). Results indicate that anthropogenic activities, such as
gold extraction, partly drive As distribution. Geoaccumulation and Pollution Indices reveal varying levels of
pollution in As, Cr, and Pb. Health risk assessments, using deterministic and probabilistic methods, found that
while non-carcinogenic risks were within safe limits for adults (Hazard Index [HI] < 1), children faced higher
risks (HI > 1) for As, Cr, Co, and V. Carcinogenic risks for both groups were within the acceptable threshold
(10− 4
–10− 6
), with children at greater risk. Ingestion was identified as the primary exposure pathway. The study
highlights the higher susceptibility of children to PTE pollution, emphasising the need for interventions to
mitigate risks from PTEs.
Provenance And Source Area Weathering Of Sandstones From The Tarkwaian Group At The Northeastern Extent Of The Paleoproterozoic Ashanti Belt, Ghana: Constraints From Petrography And Geochemistry.
(Journal of African Earth Sciences, 2025-01-09) Sedziafa, V.; Song, Y.; Sunkari, E.D.; Kwayisi, D.; Anani, C.Y.; Asiedu, D.K.
An integrated geochemical and petrographic study was conducted on the Paleoproterozoic sandstones of the
Tarkwaian Group exposed at the northeastern extent of the Ashanti Belt, Ghana. Recognizing the economic
importance of the Tarkwaian Group, particularly owing to its extensive gold deposits, the primary objective was
to investigate the provenance, tectonic setting, and crustal evolution of the Tarkwaian Group. The dominant
quartz (polycrystalline and monocrystalline), together with minor muscovite, feldspar, hematite, and lithic
fragments, characterize the sandstones and thus, the sandstones are classified as sublitharenite, and lithicsubarkose. Based on mineralogical composition and major element content, the sandstones can be classified as
litharenite, sublitharenite, and minor greywacke. The high values of SiO2/Al2O3 (average: 12.74), relatively
moderate values of K2O/NaO2 (average: 1.42), and high quartz content (average: 88%) suggest that the sediments are compositionally sub-mature to mature. The sandstones likely underwent low to moderate levels of
sedimentary sorting and recycling owing to angular to sub-rounded grains and moderate Zr/Sc and Th/Sc values.
The high Chemical Index of Alteration (CIA) signature (average: 76.79 wt%), Plagioclase Index of Alteration
(PIA) values (average: 90.13 wt%), and Index of Compositional Variability (ICV) (average: 0.61 wt%) suggest
moderate to intense chemical weathering within the region of origin. Overall, the mineralogical and geochemical
features of the sandstones, such as a high proportion of quartz and feldspar, and elevated concentrations of
elements such as Zr, Sc and Th, and moderate to high ratios of Al2O3/TiO2 and La/Sc indicate that they were
likely sourced from felsic to intermediate igneous rocks and deposited in an active continental margin such as
magmatic arc setting.
Petrology And Geochemistry Of The Suhum Basin Granitoid Complex, Ghana: Implications For Crustal Growth During The Rhyacian Orogeny Of The West African Craton.
(Journal of African Earth Sciences, 2024-11-12) Kwayisi, D.; Amponsah, P.O.; Awunyo, E.K.; Sapah, M.S.; Sakyi, P.A.; et al.
The Suhum Basin granitoid complex is an important granitoid complex of the Birimian terrane of Ghana for
unravelling the crustal growth and evolution of the West African Craton (WAC) during the Rhyacian Eburnean
orogeny. Almost the entire Suhum Basin is occupied by an extensive granitoid complex, which contains useful
information for constraining debatable plate tectonic issues, especially during the Archean-Paleoproterozoic
transition period. We present petrography, whole-rock geochemistry, and mineral chemistry data of biotite,
amphibole, and plagioclase to constrain the temperature-pressure conditions of emplacement, petrogenesis,
tectonic setting, the evolution of the granitoids complex of the Suhum Basin, and its implications for the crustal
growth and evolution of the WAC. Four lithological types; granite gneiss, migmatites, leucogranites, and mafic
enclaves, characterise the granitoid complex of the Suhum Basin. Biotites from the granitoid complex have an
annite-siderophyllite composition, and that, coupled with their calc-alkaline and I-type signatures, indicates
crystallisation of the granitoid complex of the Suhum Basin under oxidised conditions. The medium-to high-K
character of the rocks, together with the calc-alkaline nature, may be a reflection of the generation of magma in
regions where the mantle wedge might have interacted with enriched fluids from the underlying plate during
dehydration. The enrichment of LILE and LREE relative to HREE and HFSE and the negative Eu, Nb-Ta, and Ti
anomalies of the granitoids complex may indicate derivation from enriched magma sources with varying degrees
of fractionation in an arc environment. Amphibole-plagioclase thermobarometry indicates that the granitoid
complex formed at P-T conditions of 600–712 ◦C and 5.2–7.2 kbar, signifying a deeper depth (19–27 km) of
emplacement. The overall geochemical data suggest that the rocks formed during a single orogenic event related
to a volcanic arc environment where subduction zone components played a role in the generation of their
parental magmas. This finding is therefore consistent with the onset of “modern-style” subduction-related pro cesses during the Archean-Paleoproterozoic transitional period.