This study showed total excreta produced by 73 people (19 male adult, 19 female adult, 17 male children and 18 female children) was 18.97kg per day. Given an average household of 5, (2 adults and 3 children), 1321g (1.3kg) of feaces would be generated. Therefore, 500 households in any of the communities would generate 660,500g (660.5kg) of excreta. The cumulative volume of gas generated from 5kg of human excreta, combined with 15 kg of leftover rice; 5kg of vegetable waste and 25kg of water resulted in 0.167m3 biogas. By extrapolation, 500 households, generating 515kg of excreta; using 1,546kg of waste rice; 515kg of vegetables waste and 2,579kg of water, can generate 83.5m3 biogas. This quantity of biogas can power 55kw electricity generating set which can provide Community Street light for more than 6 hours. In the coastal communities of the Niger Delta where modern waste management practices are practically nonexistent, human excreta and household food wastes are discharged directly into the rivers and creeks, resulting in obnoxious effects such as foul smell, pollution and filth and even mosquito infestation. The outcome of this research has given a clear direction on how to treat domestic wastes (which in effect are resources) for bioconversion. As the world in general is changing from over reliance on fossil fuels, being wasting assets, coupled with the attendant pollution and degradation of the environment, investment into alternative energy sources such as biogas from wastes would contribute to the quest to reduce energy scarcity, guard against ecological disasters, elimination and/or control deforestation and erosion of the soil surface in particular and the environment in general. Therefore, for developing countries of Africa and especially Nigeria to surmount her current energy, environmental, food, health and unemployment crises, the anaerobic digestion of biodegradable wastes in general; excreta/household food wastes in particular should be given the attention it deserves.

Seismic and Well-log data covering three wells in tau(τ) Field in the Niger Delta were used for density modelling. Using Hampson Russell Software, Gardner’s and Lindseth’s relations were localized and subsequently transformed to obtain local fits constants for sand and shale lithologies which were used to achieved the final models. The seismic inversion was performed using four steps: well-to-seismic tie, geology model, acoustic impedance inversion and density prediction. A relationship was established between impedance and density. Pairing Gardner with those by Lindseth approaches and also obtained the average, the final models are ρ=0.1572Z_p^0.2126-16997Z_p^(-1)+1.5625 and ρ=0.09045Z_s^0.1935-7093.5Z_s^(-1)+1.4706 for sandstones lithology; ρ=0.3185Z_p^0.3103-6510Z_p^(-1)+1.42855 and ρ=0.16145Z_s^0.2308-34203.5Z_s^(-1)+1.42855 for shale lithology. These models yield a new concept which will contribute to global knowledge. In the absence of density log, these equations can be used to estimate density in the area.

Survey research method was adopted for this study. A total of 300 households, from three (3) zones (Azuabie/Slaughter, Tourist Beach and Eagle Island Coastal Communities) formed the population of this study. The data collection instrument consisted of structured questionnaire, which contained information on socio-economic and demographic characteristics of the respondents and the acceptance or otherwise of using excreta to generate energy (electricity). The result showed 83% are literate among the Azuabie respondents while those at Tourist Beach and Eagle Island were 90% and 81%, respectively. This probably made them receptive to the idea of generating useful energy from their wastes even though most of them were unaware of the biogas technology. On the issue of converting and using the human excreta, the level of awareness by the respondents was quite low. At Azuabie, 60.4%, at the Tourist Beach 71.7% and at Eagle Island 60.3% have never heard about it. It could be seen from the above that, more than halve of the respondents are unaware of the biogas technology, talk less of considering it as an alternative source of energy. Be that as it may, majority of the respondents welcomed the idea of an innovation that would convert excreta into electricity that they so desperately need. At Azuabie, 79.2% accepted this proposition, while 81.7% and 74.6% equally accepted at the Tourist Beach and the Eagle Island coastal communities respectively. Ironically, request for respondents to provide their excreta for the research was met with skepticism and rejection. At Azuabie, 62.3% were unwilling, while at the Tourist Beach, 81.7% were not ready. However, 44.4% of respondents at the Eagle Island were willing to provide their excreta for the research. Lastly, there is no significant agreement among the residents to accept the use of the energy produced from the conversion of such wastes.

The hydraulic properties of deeper Coastal Plain Sands, which form the main aquifer in the Niger Delta, were investigated around Eleme, Rivers State. The intent was to find out if frequent well failure was as a result of the aquifer not having enough transmitting capacity to sustain the huge withdrawal necessary for Eleme and its environs where demand for groundwater withdrawal is very high because Eleme axis serves as a major industrial axis of River State or whether the frequent well failure was due to inefficient well construction practice. Constant discharge pumping tests were conducted in 8 deep borehole (250 - 310 m). Data generated during the test were analysed using Cooper-Jacob's straight line method. The calculated transmissivity of the aquifers ranged from 1324 m2/day - 5815 m2/day. These values when compared with transmissivity values elsewhere indicate that the aquifers in the study area have excellent water yielding properties, plotting within the range of "Very Good" in water transmitting capacity scale. Coefficient of permeability ranged from 13.65 m/d - 59.9 m/d. Coefficient of Storage ranged from 28.2 × 10-5 - 29.1 × 10-5 while the Specific capacities of the wells ranged from 48.75 3 - 78.13 m3/d/m. It is concluded that the deep aquifers of the Niger Delta do possess the capacity to produce and sustain large groundwater withdrawal. It is further recommended that competent drilling contractors be engaged in deep well construction in the area.

The generation of tsunamis with the help of a simple dislocation model of an earthquake and their propagation in the basin are discussed. In this study, we examined the formation of a tsunami wave from an initial sea surface displacement similar to those obtained from earthquakes that have generated tsunami waves and its propagation through the sea to the shore. Linear shallow water wave equations were employed to explain the propagation of the waves in the open sea while nonlinear wave equations were introduced to explain the behaviour of the wave near the shore. The influence of the Coriolis force on the propagation of tsunami was shown to become very important when the tsunami travel distance is significant in relations to the earth’s complete rotation time. The group velocity of tsunami waves which is the velocity of wave energy propagation and its independence on the wave number was demonstrated

PurposeThe purpose of this paper is to review oil spill incidents and pipeline vandalism in Nigeria between 1970 and 2006 and to examine the potential danger posed by such activities to public health.Design/methodology/approachThe approach adopted to achieve this objective is questionnaire administration on health impacts. Also secondary sources of information come from textbooks and journals. However, data from natural resources exploitation and hazards are collated and analyzed.FindingsIt is evident that, out of the 1,000 reported oil spill incidents analyzed, some hundreds of thousands of barrels of oil are lost to the environment. Graphic pictures of typical oil spill through acts of vandalism in Ishiagu, Ebonyi State, Nigeria are analyzed and reviewed. The run‐off and sedimentation of this pollutant in fresh water systems severely degrade water quality, affect fish spawning and aquatic invertebrates' habitats, thus lowering food web productivity. Incidentally the spill‐over effect on humans who directly depend on fish and other aquatic food as an alternative protein supplement is quite inundating. The effects on humans include irritation, dermatitis, cancer, occurrence of abortion, organ failure and genetic disorder.Research limitations/implicationsThe limitations encountered in this research work include logistics problems, poor response and uncooperative attitude from respondents, transportation difficulties and restricted access to impacted sites by law enforcement agents and funding. Therefore subsequent researchers in this area should be equipped adequately with both the necessary protective gadgets and increased funding to meet challenges of this nature.Practical implicationsThe practical implication of the study is that oil spill incidents should be documented and reported early enough for prompt attention by the regulatory agencies in order to protect and enhance the quality of the environment.Originality/valueThe value of the paper is that oil spill and pipeline vandalization devastate the environment, pollute dependable potable water sources such as streams and rivers and should be seen as a serious threat and negation to the attainment of the United Nations Millennium development goals.

Thermal conductivity estimates are computed from nineteen petroleum wells in the northwestern Niger Delta, Nigeria, using a geometric mean model. Sonic and gamma-ray logs were digitised and used in the estimation of in situ conductivity. The Niger Delta is composed of three major diachronous lithostratigraphic units of shaly Akata, shaly-sandstone Agbada and sandy Benin formations, which form the bulk of the deltaic sediments. All the wells used in the study could only penetrate the top-most Benin and the underlying Agbada formations, except Akata that is the last deeply lying formation. Mineralogy, porosity and lithology exert the most important control on the matrix thermal conductivity in the Niger Delta sedimentary basin. There is a decrease of thermal conductivity with increasing shale fraction. The bulk conductivity also show an increase with increasing sandstone fraction. Increase in porosity results in a decrease in bulk conductivity. Thermal conductivity values and variations for a given lithologic unit are reduced at increased porosity, such that thermal conductivity of the top-most continental Benin sand-stone formation vary between 2.39W/m°C and 2.74W/m°C with an average of 2.52W/m°C. Thermal conductivity for the underlying, marine shaly-sandstone Agbada formation varies between 2.16W/ m°C and 2.69W/m°C with an average of 2.33W/m°C. Keywords: Thermal conductivity, porosity, lithology, well logs, geometric mean model, Niger Delta Basin, NigeriaDiscovery and Innovation Vol. 19 (4) 2007: pp. 269-275

An investigation was conducted into the suitability of either of the batch or continuous (CSTR) digesters for anaerobic degradation of municipal solid waste (MSW) in the production of biogas. Mathematical models were developed for the design and evaluation of the two systems. The development of the models was based upon a material balance analysis of the digesters'operation. A Microsoft Visual Basic Version 6.0 Programme was developed for the solution ofthe model equations, and the digesters' operations simulated over a range of percentage total solids (PTS) concentration of 4-10% for the CSTR and 4-30% for the batch digester, and fractional conversion of 0.2-0.8. The results of the simulation show that although the amount of methane (0.0764m3) produced per unit volume of the batch digester is about 4 times less than the amount (0.284m3) per unit volume of the CSTR, the cost per unit volume of the batch digester ($5.98) is 6 times less than that of the CSTR ($33.8), suggesting that the overall cost of producing gas with the batch digester would be more economical. So, it was deduced that the batch digester is better suited for the digestion of MSW for biogas production, compared to the CSTR

Municipal Solid Waste (MSW) contains a relatively large amount of organic matter, which decomposes by the actions of microorganisms under anaerobic conditions to produce biogas. The total solids (TS) concentration of the waste influences the pH, temperature and effectiveness of the microorganisms in the decomposition process. This work investigated various concentrations of the TS of MSW in an anaerobic continuously stirred tank reactor (CSTR) and the corresponding amounts of biogas produced, in order to determine conditions for optimum gas production. Five laboratory-scale anaerobic batch digesters of 5 litres volume each were set up for the digestion of 2kg of shredded MSW diluted to a %TS concentration of 26.7%. The results from the batch experimentation were adapted to the design of a CSTR for the digestion of MSW. The CSTR was simulated over a range of %TS concentration of 4-10, at a maximum fractional conversion of 0.8 to cater for system inefficiencies. Mathematical models were developed for the process and solved using the Microsoft Visual Basic version 6.0 Programme. The results show the amount of biogas produced as a power function of the %TS concentration, indicating that as the process continues, a time comes when any marginal increase in the %TS concentration would no longer contribute to the increasing volume of biogas produced. The results further show that, given the limiting upper boundary of the %TS concentration, optimum biogas production in a CSTR digesting MSW cannot be ascertained with the concentration of the %TS alone.

Municipal solid waste (MSW) contains a relatively high proportion of organic matter, which, when allowed to decompose under the actions of microorganisms, yields biogas. The amount of water available, dictating the level of pH, temperature, etc. of the system, largely influences the conditions for the effective performance of the microorganisms in the decomposition process. Total solids concentration expresses the relative proportion of the amounts of solids and liquid in the system. This work investigated various proportions of solids and liquid in MSW in an anaerobic batch digester and the corresponding amounts of biogas produced with a view to optimizing gas production from the system. Five laboratory-scale anaerobic batch digesters of 5 litres volume each were set up for the anaerobic batch digestion of 2 kg of shredded MSW diluted to a percentage total solids concentration of 26.7%. From the results of the investigation, mathematical relationships were developed to evaluate the operation of the digester and solved using the Microsoft Visual Basic version 6.0 Programme. The digester's operation was then simulated over a range of percentage total solids concentration of 4-30, at a maximum fractional conversion of 0.8 to cater for system inefficiencies. The amount of biogas produced in the digester was a power function of the percentage total solids concentration, indicating that at some point in time any marginal increase in the percentage total solids concentration was not relevant to the increasing volume of biogas produced. The results showed that optimum biogas production occurred at 20% total solids concentration.

The production of biogas is of growing interest as fossil-fuel reserves decline. However, there exists a dearth of literature on the design considerations that would lead to process optimization in the development of anaerobic digesters aimed at creating useful commodities from the ever-abundant municipal solid-waste. Consequently, this paper provides a synthesis of the key issues and analyses concerning the design of a high-performance anaerobic digester.

Six very low frequency electromagnetic (VLF-EM) lines were surveyed across the expected strike of a lead sulphide lode in a mine in the Abakaliki lead/zinc field of Nigeria. The aim of the survey was to investigate the lateral extension of the lode and establish the potential of this tool for mapping sulphide deposits in an area underlain principally by shales. VLF-EM field values were filtered using Fraser filter and the results plotted directly over the survey lines. The plots were examined for significant anomalies that could be related to the lode. About 40 m length of the lode was successfully mapped by this simple, inexpensive tool. The anomalies strike NW–SE following the strike of one of the predominant set of faults. A depth of 10 m and a dip of 90° were calculated for the conductor.

A total of 14 upholes were shot in the Mangrove Swamp of the Niger Delta of Nigeria. The aim of the survey was to determine the thickness and velocity of the low velocity layer (LVL). The velocities and thickness of the layers were computed from the reciprocals of the slopes of the straight-line segments using the FACE Static computer program. Results obtained showed a variation in the thickness of the weathering layer from 2.0m to 5.7m with an average of 3.40m. The variation was random and did not show any trend. The velocity of the low velocity layer ranges between 295ms-1 and 727ms-1 with an average of 562.7 ms-1 while the velocity of the sub-weathering layer ranges between 1502 ms-1 and 1918 ms-1 with an average of 1716 ms-1. These data are important in seismic static corrections and in geotechnical engineering. Key words: Thickness, Velocity, Low velocity layer, Uphole [Global Jnl Pure & Appl. Sci. Vol.9(3) 2003: 369-374]

Wanakom and its environs are underlain by shales of the Asu River Group which have been intruded by diorites and gabbros during the Santonian orogeny. Electromagnetic and magnetic measurements were made over the area along seven profiles spaced 900m apart on 328° Azimuth. Interpretation of the Electromagnetic (EM) and magnetic data reveals three anomalies that can be correlated with igneous rocks of moderate magnetic susceptibility. These anomalies strike NE-SW, the dominant structural trend. Weathering and fractured overburden are the sources of high background level adn large amplitude variations of the inphase and quadrature components and reflect its thickness and conductivity espacially at high frequency. Two other isolated anomalies have a conductive zone which dips at 90° with a conductivity thickness product of 140 and 100 siemens at depths of 8.1 and 7.2 meters. Drilling may prove the presence of mineralization.

The nature and chemical composition of mine pit-water was investigated in Ishiagu lead/zinc (Pb/Zn) mine in southeastern, Nigeria. Laboratory determination of some physicochemical parameters namely, temperature, total dissolved solids (TDS), conductivity , chloride, pH, alkalinity, hardness, sulphate and dissolved metal constituents like calcium and magnesium were assessed in the three mine pits using standard methods. The results showed that Ishiagu Pb/Zn mine is slightly acidic with moderate levels of dissolved metal constituents. Seasonal variation observed in the parameters indicate higher levels for pH (6.7-8.1), alkalinity (36.4--115.3mg/l) and sulphate (6.8-84.4) in the wet season when compared with corresponding values, pH (6.1-7.3), alkalinity (31.3- 98.4mg/l) and sulphate (6.1-78mg/l) in the dry season. The consistently the higher levels of pH, alkalinity, hardness, calcium, magnesium, total dissolved solids (TDS) and conductivity in more than 66% of the mine pits (mine 1and mine 3) investigated across the season is an indication of changing state of the mine pit-water to more alkaline mine drainage. This phenomenon is attributable to preponderance and buffering effect of carbonate minerals in the area.