IOSR-JAGG   Volume-2 ~ Issue-4 ~ JULY-AUG-2014

Abstract: A design of electrode disk device of Electrical Resistivity (ER) has been tested its stability of the data and its relationship closeness with the electrodes stick devices. The designed electrode device was easy to use and recorded data quickly and accurately. The design of this device consisted of a sleeve electrode, a disk-shaped electrode, and shockbreaker; it was also equipped with wheels and a tool box. A testing process of the disk electrode device was done by measurements of apperant Electrical Conductivity (ECa) repeatedly to see the consistency of data measurement, with a correlation value of 0.988. The testing was also done by correlating the ECa data between the use of the disk electrode and the use of the stick electrode, with a correlation of 0.985 . The results of the testing showed that the disk electrode could be applied quickly and accurately to the ECa measurement of agricultural land with uneven topography and levees lied on rice fields.

Key words: Electrical Resistivity, apparent Electrical Conductivity, disk electrode device.

Abstract: An assessment of the geotechnical parameter in the formation of gullies in high risk erosion areas such as Mbaukwu town of south-eastern Nigeria is presented. The soil around the Mbaukwu gully erosion sites were investigated by collecting samples from the gully channels and excavation trial pits. The trial pits depth ranges between 0-1.0m and 0-1.5m, also samples were collected at depths of 35, 60, and 62m along the gully channels. Eight disturbed and undisturbed samples were collected and analyzed. Sieve analysis, Atterberg limits and Compaction tests were carried out on the selected soil samples. The soils are generally not uniform even though similarities exist between some. The liquid limit ranges from 32.00 to 46.00 and has a mean of 35.95. The Plastic Limit ranges from 17.50 to 28.10 and has a mean of 21.15. The Plasticity Index ranges from 10.50 to 20.00 and has a mean of 14.80. The Maximum Dry Density (MDD) ranges from 2.001 to 3.910 and has a mean of 2.490. The Optimum Moisture Content (OMC) ranges from 7.90 to 11.00 and has a mean of 8.980.Result of geotechnical investigation and laboratory analysis showed that the soil in the study area is majorly loose sand. They contain very small amount of clay which serves as a binding material. The lithology of the area is dominated by sandstone with very little binding material and is one of the chief reasons for the high intensity of the gullies in the area. The maximum dry density values are generally low which indicates that the soils are unconsolidated and friable. Enlightenment and awareness of erosion control should include land use habits of the people in their agricultural practices and care of vegetation. Concrete terracing of gully affected areas is recommended to reduce the impact or the force of rain-drop. This will restrict the widening of incipient gullies. Holistic rehabilitation development programs of monitoring the earth surface to reclaim devastated land as well as to ensure a safe environment should be encouraged.
Keywords: geotechnical properties gully erosion, maximum dry density, optimum moisture content, Mbaukwu..

Abstract: In India silica sands are produced from loosely consolidated sands and weakly cemented sandstones ranging from Recent to Pre-Cambrian in age. In this paper an attempt has been made to estimate the silica sand resources, belonging to Holocene age, located at about 20km east of Gudur town, Nellore District, Andhra Pradesh. Silica sand occurs in this region as dunes of marine origin covering an area of 110 Sq.Km. Ayyavaraiah et al (2013) reported that production and reserves estimated and declared by State Mines & Geology and Indian Bureau of Mines do not match and a difference exists. Hence an attempt has been made to estimate the actual reserves of silica sand deposits of this area using Google Earth imagery, GIS and field auger hole data. The total area that was mined already is about 9.538 Sq.Km. amounting to 117 Million Tons of silica sand that was produced in past 10-15 years with 59 Million Tons still to be excavated in the currently active mines. By surface area mapping using GIS, the prospective areas for further exploration and exploitation are suggested, giving rise to total prospective reserves of silica sand of 849 Million Tons.
Keywords: Glass-grade silica sand, Resource evaluation, GIS, Gudur, Nellore Dt., Andhra Pradesh

Abstract: GIS and spatial analysis have enjoyed a long and productive relationship over the past decades. GIS has been seen as the key to implementing methods of spatial analysis, making them more accessible to a broader range of users, and hopefully more widely used in making effective decisions and in supporting scientific research. It has been argued (e.g. Goodchild 1988) that in this sense the relationship between spatial analysis and GIS is analogous to that between statistics and the statistical packages.

Keywords: Spatial Distribution, GIS, Statistical Analysis, Poisson distribution.

Abstract: Hydrogeological work was carried out to providing an alternative source of portable water supply to Omoku and its environs as their major source of water which is surface water had been contaminated/polluted by oil and gas exploration, exploitation and other anthropogenic activities in the area. To obtaining reliable data and achieving the aim, geoelectric sounding method and Schlumberger array was employed with the use of a digital averaging instrument ABEM terrameter SAS 300 model that displays the resistance measurements directly with a maximum current electrode separation (AB) of 100m. WinResist software computer iterative procedure was used, which aided to obtaining interpreted depths and resistivities from field data. The results of the geoelectric survey were tied to various lithologies by calibrating the geoelectric values with borehole data which enabled us to establish the aquiferous zones. The aquifers were located at depth of about 22m to 30m based soil profile and high resistivity values ranging from 3415m to 4555m. The information from the findings can be successfully used to harnessing and supply safe, portable and sustainable water to the people of Omoku and its environs in Rivers State, Nigeria.

Keywords: Groundwater, aquifer, geoelectric layer, Vertical Electrical Sounding (VES)

Abstract: Four (4) magnetic profiles were established for the evaluation and the magnetic anomaly map, the regional geology and its Residual Magnetic Anomaly helped in identifying the nature and depth of the magnetic sources in the study region. The magnetic residual values range from -134 nT to +116 nT. The depth to bed rock from the four profiles taken across profiles A-A', B-B' C-C' and D-D' are 2.40km, 2.23km, 0.90km and 1.60km respectively. The area shows magnetic closures of various sizes at the Western part of the study area trending Northeast-Southwest and West-East. From the Residual map, Anomalies high are observed at the southern part of the study area reaching a maximum value of +116nT around Malleri and Dukul villages while Anomalies low were also observed at Northeastern part of the study area reaching a minimum value of -134nT around Bajoga and Bage towns.