by Salahddine Didi, Humberto Bracamontes del Toro, Fatima Ezzahra Housni and Abdessamad Najine
Original Research
A geophysical study based on 49 electric holes with a long line length (up to 4 km) was carried out in the southwestern part of the plateau of Meknès (Morocco). This is located between the Rif to the north and the Middle Atlas to the south. The plateau of Meknes contains two main aquifer formations: the groundwater of the Plio-Quaternary and the deep layer of the Lias. The quantitative interpretation of the electric soundings, the geological data and the description of the drillings made it possible to draw isoresistivity and isopaque maps. These maps helped to better understand the hydrogeological structure of the region from a quantitative and qualitative point of view.
Journal of Geosciences and Geomatics. 2017, 5(4), 205-217. DOI: 10.12691/jgg-5-4-5
Pub. Date: August 31, 2017
8097 Views1963 Downloads
by Rendy Putra Maretika
Original Research
There are many commercial software that can be used to perform Digital Surface Model (DSM) extraction from stereo satellite imagery based on Rational Function Model (RFM), however the license price is quite expensive. Therefore, this research aims to build the new software prototype for DSM extraction from stereo satellite imagery based on RFM, by using free development tool and integrating various components or libraries that are non-commercial (free and/or open source). The method applied in the software prototype consists of 3 main steps, i.e. conjugate points collection manually and automatically using image matching with RFM based Cross Correlation method, Forward RFM based Virtual Intersection to perform 3D reconstruction of conjugate points, and interpolate data conjugate points with Ordinary Kriging method to establish DSM in the raster format. Stereo satellite imagery of WorldView-2 which is equipped with Rational Polynomial Coefficients (RPCs) from the vendor was applied to verify the DSM accuracy that obtained from the software prototype. Based on RFM formed from the RPCs can be obtained DSM with accuracy of 2.47639575534581 meters in planimetry (CE90) and 4.21487430387638 meters in height (LE90).
Journal of Geosciences and Geomatics. 2017, 5(4), 195-204. DOI: 10.12691/jgg-5-4-4
Pub. Date: August 25, 2017
16784 Views2928 Downloads
by Samuel K. Abanyie, Steve Ampofo and Nang Biyogue Douti
Original Research
The quality of any water for drinking purposes has grave consequences on the health and wellbeing of humans. As a result, the monitoring of groundwater in any region is crucial. Geographic Information Systems (GIS) can be used to monitor the quality of groundwater in any area with respect to time and space to avoid health challenges that may be encountered. This study aimed to access the quality of groundwater in three districts in the Northern Region of Ghana using GIS. Water quality data of 254 boreholes from the three districts were used for this study, for which the following parameters were considered: Fluoride, Chloride, Manganese and Iron. The GPS coordinates of the boreholes were used to produce a spatial distribution map using Geographic Information Systems (Arc GIS Version 9.3) in detailing the selected water quality attributes in the three districts. Fluoride concentration in Gushiegu was very high in the central part of the district. Savelugu-Nanton also had high concentrations of fluoride scattered within the district. It is recommended in communities where the groundwater was not suitable for drinking purposes, it may be used for agricultural purposes, or the water be treated before use.
Journal of Geosciences and Geomatics. 2017, 5(4), 186-194. DOI: 10.12691/jgg-5-4-3
Pub. Date: August 10, 2017
12856 Views2293 Downloads
by Guedjeo C. S, Kagou Dongmo A., Wotchoko P., Nkouathio D. G., Chenyi M. L., Wilson Buma G and Kamgang K. V
Original Research
The Bamenda Mountain (with over 250,000 inhabitants) is one of the strato-volcanoes along the Cameroon Volcanic Line (CVL) with an accidental landscape. This area is frequently affected by landslides, which most at times result in destruction of property and loss of lives. An informative value statistical method using GIS is use to prepared a landslide susceptibility map for the Bamenda Mountain area as well as a quantitative and qualitative risk assessment. This is aimed at revealing areas where future landslide would occur and potential loss. Nine landslide controlling factors including; slope, slope orientation (aspect), curvature, stream density, proximity to roads, geomorphology, proximity to streams, geology and land use were use in the model. A total of 64 slides were inventoried in the area and use to prepare the landslide density map. The weighted informative values for the combined factor and landslide density were used to prepare the landslide susceptibility map for the area. The most significant landslide causing factors in this area are; slope, stream density and slope aspect. The susceptibility map was classified into very high (17.8%), high (25.9%), moderate (33.6%) and low (22.7%). The validated model using the success rate curve indicates that the area under curve is 0.823 and predicts landslides at 82.3% in relatively high classes. Landslide risk assessment in the area indicates 406 buildings, 2,436 people, 1,291.1km of roads, 2152 ha of farmland and an approximate USD83,540,000 worth in assets are expose to high and very high risk. This approach can be implemented in other areas along the CVL to map and assess landslide risk.
Journal of Geosciences and Geomatics. 2017, 5(4), 173-185. DOI: 10.12691/jgg-5-4-2
Pub. Date: August 01, 2017
19838 Views3886 Downloads
by Obi E. O., Abong A. A and Ogbeche J. U
Original Research
The rate at which earthquake occurs in Taiwan was investigated for the period of fifty years (1961 – 2010). The result shows that the study area is characterized predominantly by minor, light and moderate earthquakes with the percentage of strong and major extremely low. The result also revealed that for each magnitude range, the number of shallow focus earthquakes is more than the intermediate focus earthquakes. No deep focus earthquake was observed. The shallow earthquake events with magnitude 4.0-4.9 (light) were the most frequent, followed by 5.0-5.9 (moderate), 3.0-3.9 (minor), 6.0-6.9 (strong) and the least frequent were with magnitude 7.0-7.9 (major). While for intermediate earthquakes, events with magnitude 4.0-4.9 were the most frequent, followed by 3.0-3.9, 5.0-5.9, 6.0-6.9 and the least frequent with magnitude 7.0-7.9 . It was also discovered that about three (3) shallow earthquakes occur monthly and about two (2) intermediate earthquakes occur yearly in Taiwan on the average. Furthermore the b-values were calculated for shallow and intermediate focus earthquakes to be 0.80 and 0.74 respectively. The b- values were calculated using the Gutenberg-Richter Relation. The low b- value indicates localized high stresses which are favourable for future rupture.
Journal of Geosciences and Geomatics. 2017, 5(4), 167-172. DOI: 10.12691/jgg-5-4-1
Pub. Date: July 31, 2017
10381 Views1825 Downloads