Application of Ground and Aeromagnetics as Reconnaissance Tool for Hydrocarbon Exploration in Part of Ikom Embayment and Lower Benue Trough, Nigeria

In addition to ground magnetic survey carried out in the study area to appraise its hydrocarbon potentials, three aeromagnetic maps on a scale 1:100,000 covering part of Ikom Embayment and Lower Benue Trough were manually digitized and analysed using computer-based programmes such as HDEP, SURFIT, MFINITE, MFFILTER, MFDESIGN, JMERGER, FRTP, PC CONTOUR, P2 GRID, OASIS MONTAJ, GEOCON AND SURFER 9.0 to determine the depth to basement as well as the configuration of the sub-basins within the study area. The average depth of the shallow and deep basins is 1.5Km and 2.5Km respectively with Nkum axis of the Ikom Embayment having the thickest sediments (about 4.0Km). The presence of few intrusives, thick pile of sediments and faults around Nkum- Edor area of Ikom Embayment indicates that they may have good prospects for hydrocarbon accumulation.

Application of Aeromagnetics as a Basin Depth Discriminating Tool Prior to Seismic Exploration: A Case Study of Central Niger Delta, Nigeria

Eight aeromagnetic maps and high resolution softcopy aeromagnetic data of the same area with available drilled well depth data were used for subsurface depth investigatuion in the Central Niger Delta, Nigeria. The data was processed, filtered and transformed to other grids using either Oasis Montaj  and/or USGS potential field software with their associated extension  packages. Anomaly Separation, Spectral Analysis, Euler Deconvolution, Horizontal Gradient Magnitude were done using the relevant softwares.The results of  spectral analysis, euler deconvolution and horizontal gradient depth maps generated clearly indicates that the well bottom (well B) depth of 3.234km compared with the different thematic magnetic basement depth from spectral 4.2km, Euler 6.421km, and HGM 4.0kmis effective in basement depth discrimination. The result show a unique closeness in comaparism  between already drilled depth with interpreted magnetic depth results. This indicate that the method can be reliable as a basin depth determining tool in virgin  sedimentary basins prior to seismic exploratioin

Aeromagnetic Mapping of Basement Releif Features in Parts of Lower Benue Trough (Afikpo – Ugep): Implications on Hydrocarbon Prospectivity South – East, Nigeria

Mapping Magnetic basement is an important tool in oil and gas exploration. Two (2) aeromanetic maps on a scale of 1:100,000 covering parts of the lower Benue Trough ( Afikpo sheet 313 and Ugep sheet314) were digitized manually along a total of 70 profiles lines to obtain 5422 data points. The digitized  values were contoured to obtain the total magnetic field intensity map of the study area.The merged data was processed and filtered using anomaly separation techniques to obtain the regional and residual fields, petters half width and maximum slope methods were analysed to  obtain depths to basements, also lineaments trend and 3-D surface plots were analsed. The results indicate a dominant NE-SW orientation, four faults were also identified mostly at the edges of sediments- basement contacts. the depth to magnetic  basement map reveals two identified sub-basins within two structural highs.the Afikpo area has  a structural high( afikpo anticlinorium) with depth ranging from 0.8km – 1.8km which is flanked by a depression (graben) 2.0km – 4.0km this sub-basin extends between  Abanwan to Amagu (ebonyi state) and extents to Biakpan (cross river state).also another structural high occurs between Iyamoyong and Okumeritit (cross river state) 0.8km -1.8km as horst, this is flanked by another depression (graben) within the Mkpani – Ugep area (cross river state) 2.0km -3.0 km in sediments thickness. Hydrocarbon prospectivity  within the study area should be within the  identified Grabens  that has shown grater sediments accumulation while  the areas identified as horst has less potentials for hydrocarbon prospectively

Application of Electrical Resistivity and Ground Magnetic Investigation of Ironstones Deposits in Abiati Akamkpa Lga Cross River State, Nigeria

Ironstones form part of production materials for cement production and is locally sourced in abaiti village as supply materials for nearby Dangote Cement Company. Geophysical investigations using vertical Electrical sounding technique and ground magnetic survey were employed to investigate the depth of occurrence of the suppose iron or deposits. Two profiles each of VES and ground magnetic data were acquired using ABEM SAS 1000 and GSM-19T magnetometer.The data sets were processed using manual and computer processed techniques. The magnetic data were corrected manually for diurnal variation corrections and plotted as anomaly profiles while the VES data was processed using the zoody software programme plotted as modelled plots. The magnetic depth results indicate that the iron ores are between 4-5m with magnetic susceptibilities of -40nT to -160nT. While the VES results indicate that the iron ore is exposed from surface to depth of 7.0m with resistivity values ranging between 4090.7 ohm/m - 5295.1 ohm/m . The study reveals a thin occurrence of about 7.0m of ironstone deposit and will require a more detail investigation in computing the volume of deposit in place

Reserve Estimation of Barite Deposits using Geological and Geophysical Investigations in Cross River State South Eastern, Nigeria.

Barite deposits occur mostly as concealed mineralization dominantly in shales and sandstones of Cretaceous age in Cross River State. Vertical Electrical Sounding (VES) and Horizontal Resistivity Profiling (HRP) have been carried out in areas with less mining activities. Also, field geological mapping in which the lengths and the widths of barite veins were measured has been undertaken.The geophysical data collected within 22 communities was done in 52 locations and the results indicate that the barite occurs in veins located at 10 – 12.2m depth and could be up to 40m in open mine pits. The lateral extent of the veins range from 4m to 65m from the from the horizontal resistivity profiling results, and could be traced from the field mapping to about 950m . The  general direction of the barite mineralization is  NE-SW . The result of the reserve estimate indicate that the Agoi village of Oban Massif has 1,981,177.0  metric tons of reserves, these are greater than the reserve found at mamfe embayment villages of Ekukunela and Nkarasi with reserve deposits of about 865, 684 metric tons. These reserves are also greater than those found in parts of the lower Benue trough villages of Osina and Okpoma (Ogoja) with reserve deposits of about 774, 345 metric tons.  An estimated reserve of over nine (9) million metric tons of barite have been calculated and documented for Cross River Stat for the first time. This has unarguably put Cross River State as having the largest reserve of barite in Nigeria. Keywords: Barite, VES, HRP, Reserve, geophysical, mineralization , resistivit

Overpressure/ Depositional Analysis of Parts of Onshore (X-Field) Niger Delta Basin Nigeria, Based on Well Logs Data

Overpressure in the world’s sedimentary basins are known to be allied with permeability barriers, tectonics, shale digenesis, basin structure and undercompaction factors. The Niger Delta basin has many overpressured zones with different depositional enviroments. This study was done using six drilled wells log suits in an x- field (Gama ray log, deep induction log, Density log, and sonic log). The data was acquired from Cheveron Nigeria Ltd in ascii softcopy format, which was analysed using both manual method and computer processed interactive petrophysics (IP) version 3.6 software. The logs were loaded and printed to hardcopies and digitization done at 5m interval to extract the data across the log suits. Characteristic curve patterns along the gamma log were delineated for shape patterns such as bell shape, funnel shape, and blocky to reveal paleoenviroments of the study area. The results indicate twenty one (21) overpressure zones within the wells, three (3) subsurface overpressure zones are correlated across the wells at depth interval between 3000m – 3200m for wells A,B,C,D,E and 2900m – 3000m for wells E and C , and 3600m – 3700m for wells C and F respectively,these overpressured zones occurred within a dominantly fluvial channel with minor detlaic distribution and barrier bar complexes. The areas identified as overpressured zones should be critically  examined during drilling to avoid rig blow outs

Determination of Thermal Conductivity of Some Shale Samples in Awi Formation and Its Geophysical Implications, Cross River State, Nigeria

The thermal Conductivity of some about sixty – two (62) shale samples from four locations within the Awi formation using modified Lee’s method were determined. It was observed that the thermal agitation in the sample increases as the temperature increases, after which thermal stability was attained. The Shale samples collected from location two and four tend to have high  average thermal conductivity values ranging from 1.4490 W/m0C and 1.0802 W/m0C respectively while location one and three exhibits low values of thermal conductivity ranging from 0.8544 W/m0C and 0.7027 W/m0C respectively during the rising temperature measurement. During the falling temperature measurement location two and four still have high average thermal conductivity values of 1.3020 W/m0C and 0.9884 W/m0C respectively and location one has an average value of 0.8339  W/m0C while location Three has 0.6544 W/m0C. The low values exhibited by Location one and three is largely due to the fact  that the outcrops in these locations were along the road  and have been exposed to weather and  human activities. However, the values from location two and four, suggests that shales within this location are post matured. Keywords: Conductivity, agitation, stability, outcrops, post- mature

The Impact of ICT on Career Counseling Services: A case Study of Nigerian Secondary Schools

Information and communication technologies (ICT) will need to be fully integrated into the delivery of careers services as the world is now in the global era. Such integration would not only have the potential to achieve more but would also increase the flexibility of services and enhance their quality. Career choice is an  important  decision  a  person  needs  to  make  in  his  life  time.  Unfortunately, many young people find it uneasy to make appropriate career choice. The  paper  focused  on  the  usage  of  career  counseling  services  in  selected public secondary schools in Nigeria. It sought to find out how students and teachers utilize  career  counseling  services,  students’  expectations  in  career  counseling services  and  how  school  principals  support  career  counseling  services.  Simple random  sampling  was  used  to  select  380  from 34  public  secondary  schools  from  the  sample  population.  Four-point Likert scale questionnaires were used to obtain data for the study. The findings revealed that the students use career counseling services to take career decision and aspiration, gather career information and select and take subjects that match their career interest. Secondary school teachers use career counseling services to guide students to make appropriate subject choice that match their career interest and help them with their career challenges and plans. This paper recommends that career counselors should integrate use of ICT, through the use of chat rooms, email and social networking. In other words several choice of career could be show to the students on DVD and CD Video. They should also be exposed to TV and radio Chat on Career choice.DOI: http://dx.doi.org/10.11591/ijere.v1i1.70

Oscillations of the superconducting critical current in Nb-Cu-Ni-Cu-Nb junctions

We report on experimental studies of superconductor-ferromagnet layered structures. Strong oscillations of the critical supercurrent were observed with the thickness variation of the ferromagnet. Using known microscopic parameters of Ni, we found reasonable agreement between the period of oscillations and the decay of the measured critical current, and theoretical calculations.Comment: 5 page

Molecular basis of virulence in clinical isolates of Escherichia coli and Salmonella species from a tertiary hospital in the Eastern Cape, South Africa

<p>Abstract</p> <p>Background</p> <p>Apart from localized gastrointestinal infections, <it>Escherichia coli </it>and <it>Salmonella </it>species are major causes of systemic disease in both humans and animals. <it>Salmonella </it>spp. cause invasive infections such as enteric fever, septicemia, osteomyelitis and meningitis while certain types of <it>E. coli </it>can cause systemic infections, including</p> <p>pyelonephritis, meningitis and septicemia. These characteristic requires the involvement of a myriad of virulence factors.</p> <p>Methods</p> <p>This study investigated the virulence factors of <it>Escherichia coli </it>and <it>Salmonella </it>species in clinical specimens from patients with diarrhoea presenting to health care centres in Oliver R. Tambo District Municipality, Eastern Cape Province, Republic of South Africa. Microbiology analysis involved the use of cultural and molecular techniques.</p> <p>Results</p> <p>Out of a total of 315 samples screened, <it>Salmonella </it>isolates were obtained in 119 (37.8%) of cases and these comprised: <it>S. choleraesuis </it>(6%), <it>S. enteritidis </it>(4%), <it>S. eppendorf </it>(1%), <it>S. hadar </it>(1%), <it>S. isangi </it>(8%), <it>S. panama </it>(1%), <it>S. typhi </it>(52%), <it>S. typhimurium </it>(25%) and untyped <it>Salmonella </it>spp. (2%). Among the <it>Salmonella </it>species 87 (73.1%) were invasive. Using molecular diagnostic methods, diarrheagenic <it>E. coli </it>were detected in 90 cases (28.6%): the greater proportion of this were enteroaggregative <it>E. coli </it>(EAEC) 37 (41.1%), enteropathogenic <it>E. coli </it>(EPEC) 21 (23.3%) and enterohemorrhagic <it>E. coli </it>(EHEC) 21 (23.3%). The predominant virulence gene among the diarrheagenic <it>E. coli </it>was EAEC heat-stable enterotoxin <it>astA </it>genes while the virulence genes identified in the <it>Salmonella </it>strains were 15 (12.6%) flic and 105 (88.2%) inv genes. The amino acid identity of the representative genes showed 95-100% similarity to corresponding blast searched sequence.</p> <p>Conclusions</p> <p>This study showed the diversity of virulence gene expression in two major enteric pathogens. <it>S. typhi </it>and enteroaggregative <it>E. coli </it>were the predominant enteropathogens in our study area with an indication that EAEC is endemic within our study population. It was observed among other things that some diarrheagenic <it>E. coli </it>isolated from apparently asymptomatic subjects expressed some virulence genes at frequency as high as seen in diarrheagenic cases. This study underlines the importance of understanding the virulence composition and diversity of pathogens for enhanced clinico-epidemiological monitoring and health care delivery.</p