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High‐resolution aeromagnetic data over the Bida Basin, North Central Nigeria has been analysed to investigate the possible continuity of Ifewara fault zone, through the Bida Basin, to Zungeru fault zone. Analytic signal magnitude, horizontal gradient magnitude, and Euler deconvolution methods were applied to the aeromagnetic data to delineate the subsurface structures. The results showed that a prominent NNE–SSW trending fault associated with the Ifewara fault zone extends through the study area. Other faults trending in the ENE–WSW, NE–SW, NW–SE, E–W, and WNW–ESE directions were also mapped. Interpreted models revealed the presence of intrusives and a possible mineralised zone within the study area. We therefore concluded that the inferred fault zones within the basin have affinity with the trend of the Ifewara fault zone, which is an indication of possible extension and linkage with Zungeru fault zone through the Bida Basin.  相似文献   
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Cohabitation, as a form of sexual relationship, is becoming popular among tertiary students in developing countries. This is largely due to emergence of sexual liberalization that projects premarital sex as acceptable societal norm. The paper analyses the spatial pattern of cohabitation in communities abutting tertiary institutions in Ibadan, Nigeria. Snowball sampling technique was used to identify cohabiters at Agbowo and Apete and the Coordinates of their residence were taken using Global Positioning System. Nearest Neighbour Analysis (NNA) was adopted for spatial analysis. Spatial pattern of cohabitation at Agbowo (NNA value 1.072615) shows a random pattern. The pattern at Apete (NNA value 0.802374) displays a cluster pattern. Finding identifies, ownership, use and types of building; inadequate on-campus accommodation; peer pressure and poverty as cohabitation causal factors influencing the observed spatial patterns. Therefore, parents and guardians should adopt high-investment strategy in safeguarding the welfare and wellbeing of their wards.  相似文献   
3.
The occurrence of earthquakes in oceanic trenches can pose a tsunami threat to lives and properties in active seismic zones. Therefore, the knowledge of focal depth, magnitude, and time distribution of earthquakes along the trenches is needed to investigate the future occurrence of earthquakes in the zones. The oceanic trenches studied, were located from the seismicity map on: latitude +51° to +53°and longitude-160° to 176°(Aleutian Trench), latitude+40° to +53° and longitude +148° to +165°(Japan Trench), and latitude-75° to-64° and longitude –15° to+30°(Peru–Chile Trench). The following features of seismic events were considered: magnitude distribution, focal depth distribution, and time distribution of earthquake. The results obtained in each trench revealed that the earthquakes increased with time in all the regions. This implies that the lithospheric layer is becoming more unstable. Thus, tectonic stress accumulation is increasing with time. The rate of increase in earthquakes at the Peru–Chile Trench is higher than that of the Japan Trench and the Aleutian Trench. This implies that the convergence of lithospheric plates is higher in the Peru–Chile Trench. Deep earthquakes were observed across all the trenches. The shallow earthquakes were more prominent than intermediate and deep earthquakes in all thetrenches. The seismic events in the trenches are mostly of magnitude range 3.0–4.9. This magnitude range may indicate the genesis of mild to moderate tsunamis in the trench zone in near future once sufficient slip would occur with displacement of water column.  相似文献   
4.
The occurrence of earthquakes in oceanic tren- ches can pose a tsunami threat to lives and properties in active seismic zones. Therefore, the knowledge of focal depth, magnitude, and time distribution of earthquakes along the trenches is needed to investigate the future occurrence of earthquakes in the zones. The oceanic trenches studied, were located from the seismicity map on： latitude ＋51 ° to＋53° and longitude -160° to 176° （Aleutian Trench）, latitude ＋40° to ＋53° and longitude ＋148° to＋165° （Japan Trench）, and latitude -75° to -64° and longitude -15° to ＋30° （Peru-Chile Trench）. The following features of seis- mic events were considered： magnitude distribution, focal depth distribution, and time distribution of earthquake. The results obtained in each trench revealed that the earthquakes increased with time in all the regions. This implies that the lithospheric layer is becoming more unstable. Thus, tectonic stress accumulation is increasing with time. The rate of increase in earthquakes at the Peru-Chile Trench is higher than that of the Japan Trench and the Aleutian Trench. This implies that the convergence of lithospheric plates is higher in the Peru-Chile Trench. Deep earthquakes were observed across all the trenches. The shallow earthquakes were more prominent than intermediate and deep earthquakes in all thetrenches. The seismic events in the trenches are mostly of magnitude range 3.0-4.9. This magnitude range may indi- cate the genesis of mild to moderate tsunamis in the trench zone in near future once sufficient slip would occur with displacement of water column.  相似文献   
5.
Arabian Journal of Geosciences - Turabah area is located in the southwestern Arabian Shield of Saudi Arabia. The present study aims to shed light on the origin and mechanism of formation of the...  相似文献   
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The study of hydrochemical models and probable pollution in Euphrates River from Qaem–Al-Falluja was performed through regime observation in ten water points. The hydrochemical properties of Euphrates River waters are determined by using the analysis results of 21 physico-chemical variables during the water year (2008). The interpretation of the hydrochemical phenomena is achieved in accordance with the statistical results of Polynomial Regression Statistic, calculating the coefficient of variation among the physico-chemical components of the water terminating by 14 models. The results of monitoring during the water year 2008 indicate a pollution case by SO4 and Cd in Ramadi and downstream stations; TDS, Mg, Na, Cl, Mn, and CO2 in Ramadi station; TDS, Ca, Na, Cl, and Fe in Baghdadi station; and Ca and H T in Qaem station and Mg in Obaydi station. The research suggests the best locations for hydrochemical monitoring as continuous hydrologic stations used for the long-term monitoring. These stations are in Qaem city as inlet location and Al-Baghdadi and Ramadi cities terminating in Falluja city as outlet location. Furthermore, daily record system is recommended for the other stations in each city to complete the regime observation of Euphrates water type. From the configuration approach of hydrochemical models with the pollution phenomena, there are potential point sources of pollution such as municipal effluent pipes and reused water from mining process for building materials in the first sector of river, which extends between Qaem and Haditha dam. Also groundwater seepages and springs discharge of mineralized water mixed with sewage water from cities act as potential point sources of pollution on the river water in the second sector extended between Haditha and Ramadi scheme. The third sector of the river is affected by all reasons in the first and second sectors as well as the effectiveness of agricultural activities throughout drainage canals and irrigation projects extended between Ramadi and Falluja cities.  相似文献   
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