Open Access Original Research Article

Geochemical Pattern and the Evolution of the Mafic Rocks of Southwest Obudu Plateau, Bamenda Massif, Nigeria

E. E. Ukwang, V. U. Ukaegbu

Journal of Geography, Environment and Earth Science International, Page 1-12
DOI: 10.9734/JGEESI/2016/25536

The mafic and ultramafic rocks of southwest Obudu, Nigeria are located within the Paleoproterozoic granulites facies rocks of the Bamenda Massif. These mafic and ultramafic rocks were not subjected to high level deformation and metamorphism which the surrounding rocks experienced. Since there are no pervasive signatures of the Pan-African Orogeny, these rocks were probably emplaced as later stage intrusive into these Pan-African rocks. The unmetamorphosed dolerite and diorite occur as boulders and veins cross-cutting the charnockitic rocks of Ukwortung and the environs. The ultramafic rock massively outcrops in Ukwortung and in other localities as mostly dykes in the granulite facies rocks. The Mg# (magnesian number) for the mafic and the ultramafic rocks of southwest Obudu, southeastern Nigeria are high (Mg# ranges from 19.95 to 65.15) and the FeOT is equally high (FeOT is 9.87–13.20). The Mg number of the ultramafic rock on the average is higher than those for partial melts from the lower crust (basaltic magma, Mg# <40) lower than values for Qingbulake intrusion in China (59–81) and those for metaperidotite in ophiolites (89 – 91), suggesting that its derivation was not directly from the partial melting of the lower crust. Its formation may have involved derivation interaction with mantle peridotite. However, the Mg numbers for the dolerites and the diorites are less than 40, lower than those of partial melts from the lower crust. This precludes their formation from interaction peridotite. The LILE and LREE enrichment, considerable depletion in HSFE with low La/Nb ratios are indicative of subduction related activities. The Zr/Y (>4) and Nb/Y (>2) are suggestive of materials derived from enriched mantle source which may have been metasomatised by slab melts during subduction/collision. Variable Ce/Y ratios, the elevated Sr/Nd ratios at low Th/Yb ratios reflect the addition of fluids from a subducting slab. However the low Th/Yb ratios of the mafic and ultramafic rocks preclude importance of sediment melts from the subducting slab. Therefore, hydrous melting of the metasomatised mantle material may have introduced significant LILE into the source.

 

Open Access Original Research Article

A Regression Analysis of Residents’ Socio-economic and Subjective Wellbeing Attributes in Nigeria Western Border Settlements

Abel Omoniyi Afon, Deborah Bunmi Ojo

Journal of Geography, Environment and Earth Science International, Page 1-9
DOI: 10.9734/JGEESI/2016/25397

This paper examined the various socio-economic attributes of residents such as gender, age, income, length of stay, occupation, household size among others in Seme border settlements of  Nigeria using  data collected from a survey of 329 randomly selected residents’ in the study area. It also assessed the effects of these attributes on residents’ overall quality of life with a view to determining the implication that the socio-economic attributes have on their well-being of life. Frequency and percentage was used in analysing the socio-economic attributes Multiple Regression technique was used to evaluate the relationship that exists between these attributes and the overall quality of life of residents’. The results of the regression analysis revealed that length of stay in current residence and income among other socio-economic attributes affect the residents ‘overall quality of life in Seme border. The study therefore concluded that residents’ socio-economic attributes does not generally influence the overall quality of life of residents in the border.

Open Access Original Research Article

Examination of Land Surface Deformation in the Eastern Tennessee Seismic Zone (ETSZ) Using Persistent Scatterers Interferometric Synthetic Aperture Radar (PSInSAR)

Zhiming Yang, Abdella Salem

Journal of Geography, Environment and Earth Science International, Page 1-18
DOI: 10.9734/JGEESI/2016/26110

Aims: The purpose of this study is to detect land surface deformation in the Eastern Tennessee Seismic Zone using persistent scatterers interferometric synthetic aperture radar technique.

Study Design: This study employed persistent scatterers interferometric synthetic aperture radar technique to analyze a series of ESA SAR images and derive surface deformation velocity along the slant range direction in Eastern Tennessee Seismic Zone which is the second most active seismic zone in the eastern United States.

Place and Duration of Study: Department of Environmental, Earth and Geospatial Sciences, North Carolina Central University, Services between June 2012 and July 2014.

Methodology: In this study, forty six ESR ½ SAR (SLC format) images covering two study areas with different seismic activity were inputted to ENVI/SARscape/Persistent Scatterers Stacking Interferometry Module with DEM (10-meter resolution) acquired from USGS. These SAR images cover a part of the ETSZ, with spatial extent between 35.118 and 36.824 degrees north in latitude, and between 83.707 and 84.871 degrees west in longitude and were acquired between 1992 and 1999. After interferometric SAR analysis, ArcGIS 10.2 software was used to conduct spatial statistics of surface deformation velocity along line of sight in both study areas and to examine the land surface deformation in cities located in the west and east of the New York-Alabama lineament.

Results: It was found that average uplift/subsidence velocity was higher in the study area which was more seismically active. Results also show that there was no significant difference in average uplift, subsidence and overall velocity between two sides of New York-Alabama lineament in ETSZ.

Conclusion: Our findings indicate that there is no direct association between the land surface deformation and the position relative to the NY-AL lineament in the study areas. However, interpretation of results from this study needs to be cautious since there are many factors, in addition to seismotectonic processes, that contribute to land surface deformation. Geodetic measurements such as ground leveling measurements are highly suggested in the ETSZ to verify finding from this study and to identify the deformation sources.

 

Open Access Original Research Article

On the Mechanism of Catastrophic Caldera-forming Eruptions: Yellowstone’s Approval

Andrei Nechayev

Journal of Geography, Environment and Earth Science International, Page 1-9
DOI: 10.9734/JGEESI/2016/27330

This paper proposes and analyzes a possible scenario of preparation and development of Caldera-forming eruptions of Yellowstone. As a physical mechanism of eruption the imbalance between the column of liquid (magma in the chamber and the conduit) and closed volume of gas (fluid accumulated within the magma chamber) is considered. To demonstrate the mechanism operating a simple experiment with water is realized and described. Theoretical conditions for the supposed Yellowstone super-eruption are formulated and discussed.

 

Open Access Original Research Article

Water Tower Ecosystems Services and Diversification of Livelihood Activities to Neighbouring Communities; A Case Study of Chyulu Hills Water Tower in Kenya

Titus Ikusya Kanui, Jacob K. Kibwage, Mwobobia Royford Murangiri

Journal of Geography, Environment and Earth Science International, Page 1-12
DOI: 10.9734/JGEESI/2016/26620

The study was commissioned by the Kenya Water Towers Agency (KWTA) to provide information that would guide the agency in achieving one of its key strategic objectives of providing community livelihood support for sustainable management of water towers. The focus of the study was to provide information on how the neighbouring community benefits from Chyulu hills water tower and also provide suggestions of the community on livelihood activities that can be undertaken to ease pressure on the hills. The study was done at Chyulu hills water tower and the neighbouring community.

Questionnaires, key informant interviews, field observations, photography and Focus Group Discussions (FGD) data collection methods were used to collect data. Focused group discussions with representatives of 10 key stakeholders involved in Chyulu hills conservation and interviews through structured questionnaires to 12 randomly selected community members residing within 10 Km from the boundary of the water tower were undertaken.

Resident’s mainly apportioned their land for crop; livestock farming or both but had no land ownership documents. The main three livelihood options were livestock keeping, crop farming and poultry rearing while main crop preferences were green grams, maize and cowpeas farming. Main benefits from the forest were medicinal herbs, rain, grazing and recreation facilities. The main development options were provision of water, bee keeping, goat farming, poultry rearing, capacity building, dairy & fish farming and tree farming in the order which they are listed.

A development action plan was recommended to ease pressure and prevent destruction of the water tower. Those who benefit from the water tower could contribute towards the community development actions. The information gathered gives insights into ways of protecting water towers in Kenya and elsewhere in the world.