7 research outputs found
Physicochemical Characteristics and Heavy Metals Level in Groundwater and Leachate around Solid Waste Dumpsite at Mbodo, Rivers State Nigeria
The dump site at Mbodo study area is characterized by diverse kinds of waste, from municipal waste to industrial waste, agricultural waste, and solid waste. Hence, this study evaluated the physicochemical characteristics and heavy metals level in groundwater and leachate around solid waste dumpsite at Mbodo, Rivers State, Nigeria using standard methods after sample treatment. The physiochemical results of the underground waters were studied and the results range are pH (4.50-4.77); Total dissolved solid (7.0-8.0); Total hardness (2.40-4.04); Turbidity (0.4); Conductivity (14-17); chloride (4.6- 6.0), Nitrate (0.9). The physiochemical parameters are within the world health organization standard except for pH of the waters which indicates low pH (4.48-4.477). The low pH of the underground water could be due to surrounding factors like elemental compositions of the aquifer, the nature of the underground water, reactions of the elemental components in the water, reactions of metals at the subsurface, dissolution of confined CO2 in the underground water. The leachates have average composition of (Cu= 0.015; Mn=5.565; Fe=15.01). The heavy metals in the underground water are within the permissible limit which can be tolerated by human beings as compared with the world health organization standard. The heavy metals concentrations range from (Ca =0.06-0.11; Mg= 0.05-0.2; Mn=0.02-0.03; Fe= 0.033; Ni=0.047) while Cd, Cr and Pb are not significant. The waste dump at Mbodo study area did not have any significant effect on the proxy underground water
Api gravities and geochemical evaluation of crude oils from sapele, niger – delta, nigeria
The investigation is to provide information on source organic matter input, depositional conditions and the correlation between crude oils recovered from Sapele oilfield in the Niger Delta. A suite of twenty-five crude oils from the Agbada reservoirs (synsedimentary) of the Tertiary Niger Delta (Southern Nigeria) were analysed based on API gravities and geochemically compared with extracts from source rock of the Akata and Agbada Formations. The Sapele shallow reservoirs occur between the depths of 4000ft and 6000ft, containing heavy crudes with API gravities 20 – 22 degrees. The deep reservoirs lie within 7000ft and 12000ft accumulating the light crudes with API gravities of 24.70-35.60 degrees, and viscocity of 1.64cP. The investigated biomarkers indicated that the Sapele oils were derived from mixed marine and terrigenous organic matter and deposited under suboxic conditions. This has been achieved from normal alkane and acyclic isoprenoids distributions, terpane and sterane biomarkers. These oils were also generated from source rock with a wide range of thermal maturity and ranging from early-mature to peak oil window. Based on molecular indicators of organic source input and depositional environment diagnostic biomarkers, one petroleum system operates in the Niger Delta Region; as observed on the source rocks from the Agbada organic – rich shale sediments. Therefore, the hydrocarbon exploration processes should be concentrating on the Akata and Agbada area of the Tertiary strata for determining the source kitchen
Pyrolytic and provenance evaluation of organic matter from the tertiary niger delta basin, nigeria: implication on hydrocarbon generation.
The present work deals with evaluation of organic matter based on detailed Rock-Eval pyrolysis techniques studies to evaluate hydrocarbon generation potential of source rocks by collecting twenty- nine shale samples from well cuttings in the Tertiary Formations of the Niger Delta, Nigeria. The values of vitrinite reflectance (0.57–0.74%Ro) and maximum (Tmax: 420–445°C) confirmed that samples are at early maturity to matured stage enough to generate liquid and gaseous hydrocarbon. The cross-plot between hydrogen index (HI) and oxygen index (OI) atomic ratio indicates that samples were predominant in the bituminous rank and having kerogen Type III makes it suitable for hydrocarbon generation. Rock-Eval pyrolysis analysis (Types II-III and Type III kerogen) on shale samples from the Niger Delta reveals organic matter of predominantly terrestrial origin based on type III kerogen. The organic matter (OM) assemblages suggests a marine setting but dominated by terrestrial inputs likely related to fluvial processes which is function of most delta system. Based on high total organic carbon (TOC) value of 5.42wt% and Type III kerogen made the shale an excellent source rock, with gas-prone kerogen. The high OI, low total sulphur (TS) suggests terrestrially derived OM and deposition in an oxic and dysoxic shallow marine environment. In addition, HI and Tmax values describe the samples as a characteristic Type III dominant kerogen and potential to generate oil and gases while the Tmax, consistently indicate an immature to mature on the shale organic matter
A Review of Rainfall Erosivity as a Natural Factor of Gully Erosion
In this 21st century which is climate change-driven with more extreme rainfall events, gully erosion is increasingly becoming a global environmental problem influenced by both natural and anthropogenic factors. This paper is a literature review of rainfall erosivity as one of the natural factors of gully erosion. The central objective of the paper is to show in a global context how rainfall erosivity has influenced gully erosion. The method used is a review of academic/journal articles, textbooks, internet materials, conference papers and publicly available materials on gully erosion and rainfall erosivity as one of its factors. Previous authors whose works were reviewed on rainfall erosivity as a factor of gully erosion have a convergent view that rainfall is the primary cause of water-induced erosion and its power to do so is known as erosivity. They were of the view that a more intense rainfall of short duration can cause gully erosion more than a less intense one for a longer period of time. The authors also have a unity of opinion that areas with high rainfall regime such as the tropics are more prone to soil erosion than areas with low rainfall events. Recommendations to reduce the influence of rainfall as a factor of soil erosion include planting of trees and grasses that reduce the impact of rainfall to detach soil particles, conservation practices such as terracing, strip cropping and contour ploughing, a shift from rain-fed agriculture to dry season farming and grants to the affected people and landholders to manage gully erosion using adaptive measures based on their indigenous knowledge
Lithofacies, Petrology and Depositional Environment of Limestone in Ohafia-Ozu Abam Area in Southeastern Nigeria
Lithofacies and petrological studies of the limestones in the Nsukka Formation were carried out so as to understand their diagenetic history and depositional environments. The Nsukka Formation in the study area consists of two facies associations; shale-limestone and cross bedded sandstone. The limestone-shale facies association consists of the following lithofacies; rippled clayey sandstone, carbonaceous shale, heterolithic sandstone-shale, laminated grey shale, fossiliferous limestone, fine grained sandstone, silty shale, medium grained sandstone and carbonaceous sandstone. The cross bedded sandstone facies association consists of only cross bedded sandstone, which is made up of fine to coarse grained sandstones. Petrological analysis of the limestones shows that the limestones consists of allochemical biosparites or bioclastic packstones and grainstones. The textural and mineralogical characteristics of the limestones show that the limestones have undergone some diagenetic processes such as cementation, neomorphism, micritization, compaction and dissolution. Dolomitization is almost absent in the limestones. The shale-limestone facies association is interpreted as sediments from a lagoon / swamp, mixed tidal flat and shoreface to shallow marine shelf environments. The crossbedded sandstone suggests deposition in a moderate to high energy, upper shoreface shallow marine environment
Lithology and economic potential resource of Igumale-Nsukka area, SE Nigeria
The Maastrichtian Mamu and Nsukka Formations in the Anambra Basin (SE Nigeria) consist of a cyclic succession of coals, carbonaceous shales, silty shales and siltstones interpreted as deltaic deposits. The studied area is located in the northern part of Nsukka within the Anambra Basin southeastern Nigeria. The aim of this investigation is to examine the litholologic and economic aspect of some rocks in this area. Four main stratigraphic units belonging to the Enugu Shale, the Lower and Upper Mamu Formation and the Ajali Sandstone were identified. The Enugu Shale is the oldest unit which forms the base of the sequence and could be subdivided into subunits; carbonaceous shale, grey shale and sandy shale. The carbonaceous shale consists of dark, soft bluish shales-thinly laminated. The grey comprises laminated shales alternating with sandstones and the sandy shale consists of alternating shale, fine sandstones and siltstones. The Mamu Formation succeeded the Enugu Shale and two members of this formation; Lower and Upper Mamu Formation are identified. The Lower Mamu Formation is made up of three subunits, carbonaceous shale, grey shale, and sandy shale. The Upper Mamu unit consists of friable fine white sandstones. The Ajali Sandstone overlain the Upper Mamu Formation and consists of whitish to pinkish red, poorly consolidated medium grained sandstones. It is well cross-bedded and contains plant impression, and burrow-fills as ichno-fossils. The sandstones are used in the manufacturing of glass while laterites are used for various construction purposes such as roads, buildings and bridges. The clays are for pottery, glazed tiles, in ceramics industry. The coal has a future prospect for industries, such as iron and steel industry as cooking coal, cement industries and raw materials for chemical industries and also use locally for cooking. The alternation of shales and sandstones in the Enugu Shales, Mamu Formation and Ajali Sandstones provide a good petroleum system.Key Words: Lithofacies, sandstone, shale, mineralogy, depositional environment potential resource
A comparison of spontaneous combustion susceptibility of coal from the Benue trough according to rank
This study investigated spontaneous combustion susceptibility of coal according to the rank. To estimate the spontaneous combustion susceptibility of coal, both crossing-point temperature (CPT) measurement and gas analysis by using gas chromatography (GC) were performed. For the experiment, Ihuoma coal, Orlu lignite, and Onyeama coal and Owukpa coal that are sub- bituminous coal, Obi/Lafia bituminous coal was used. The lignite such as Ihuoma coal contains more functional groups that easily react to oxygen more so than Onyeama and Owukpa coals. Also, Onyeama and Owukpa coal more functional groups than Obi/Lafia coal. For this reason, the lignite is more easily oxidized than sub-bituminous coal and sub-bituminous more easily oxidized than bituminous at low temperature, which results in high O2 consumption, increase in CO and CO2 generation, and low CPT. Although the CPT of Onyeama coal and Owukpa coal is identical to each other as they are the sub-bituminous, Owukpa coal has a lower initial oxidation temperature (IOT) and maximum oxidation temperature (MOT) than those of Onyeama coal. This means that although each coal has the same rank and CPT, spontaneous combustion susceptibility of coal may vary because the initial temperature of the coal at which oxidation begins may be different due to the substances that participate in oxidation.Key Words: Coal rank, cross-point-temperature, spontaneous combustion, low temperature oxidation