Abstract The major lithostratigraphic units of the eastern Dahomey Basin are the Araromi, Ewekoro and Akinbo Formations. Field studies show that the Araromi and Akinbo Formations contain shaly facies, while the Ewekoro Formation contains essentially fossiliferous limestones. The Araromi shales are dark and bituminous, while those of the Akinbo are fissile and concretionary. Selected subsurface and outcrop samples of these lithotypes were analysed to ascertain their palaeodepositional environm...
Abstract Clay bodies occur as lenses and interbeds within the predominantly shaley Akinbo Formation in the eastern Dahomey Basin. They are greenish to grayish, plastic, and in some places contain concretions. In order to assess their sedimentological significance as well as evaluate their potential as industrial raw materials, representative outcrop arid borehole samples .were subjected to mineralogical, chemical and physical characterisation. • • •, •, > l j . Mineralogical determin...
Abstra c t: Since the year 2000, the city o f Gweru has had an unprecedented proliferation o f unattended potholes on most o f its roads These potholes have caused discomfort to the motoring public, caused death to others and damaged vehicles. This paper presents the results o f a study that sought to establish the spatial distribution o f potholes and determine their socio-economic impacts in Gweru’s residential areas. Pothole location and dimensions were measured in the field whilst inter...
Abstract Some intrusive rocks of doleritic to dioritic compositions horn the Ejekwe-Wanikande and Okigwe-Ishiagu districts in the Lower Benue Trough have been studied using thin section microscopy and X-ray (powder) difiaction method. The rocks have intmded pre-Santonian sedimentary rocks which are predominantly calcareous shales. The exposures of these intrusive rocks generally have widths ranging from about 40m to 228 m. s The intrusive rocks are generally melanocratic to mesocratic (dark.t...
table of contents fireword Acknuwledgemettts iii Executive Surtzmary 1. In t reduction 1.1 Main objectives and stnlcture of the paper 7 1.2 Some historical perspectives 7 The Present as a key to the future: a look at the last 20 years of the upstream oil and gas industry 2.1 Strategic and organisational changes 8 2.2 World demand for crude oil arid gas 10 2.3 Spot oil prices 10 2.4 World crude oil and gas resources 12 2.5 lmprovements in discovery and recovery rates 14 2.6 Lessons from the Gu...
ABSTRACT This project addresses the effects of increase in fines contents on the geotechnical properties of sandy soils and the roles the fines play in slope instability in Nsukka, Enugu state in Nigeria. Field investigation revealed that the major landslides and gully erosion sites in south eastern Nigeria are localized within areas where these sandy soils are present. Geotechnical investigation of these sandy soils was carried out to assess their importance in the numerous geohazards in the...
Abstract Combinations of geological, geophysical and geochemical techniques have been used to explore for gold deposits at Misaki within the Iramba-Sekenke Greenstone Belt in Singida region. The Misaki area is occupied by different rocks including homogeneous coarse-grained granite containing numerous xenoliths (> 5 vol. %), tonalite, K-rich granite, pegmatite and dolerite dykes. All granitic rocks have been intruded by dolerite dykes, cut by epidote veins and are found juxtaposed to a tonal...
ABSTRACT Geo-environmental hazards associated with active and abandoned borrow pits are on the increase following rising trend in road construction. This situation presents a major challenge to Citizens, Environmentalists and Governments. Several highway failures have been directly linked to the action of erosion initiated by active or abandoned borrow pits situated close to roads. This study investigated environmental hazards and reclamation requirements associated with abandoned borrow ...
ABSTRACT This study explored the impact of small-scale mining activities on the environment in two regions in Namibia: Erongo (examples: Uis, Neu Schwaben, Xoboxobos) and Omaheke (example: Otjinene). Limited research is done on the activities of small-scale mining in Namibia which results in unavailability of data. Although recent studies reveal that about 5 000 to 10 000 Namibians work as small-scale miners, information about mining activities in Namibia remain a rare commodity. Small-scale ...
ABSTRACT This study explored the impact of small-scale mining activities on the environment in two regions in Namibia: Erongo (examples: Uis, Neu Schwaben, Xoboxobos) and Omaheke (example: Otjinene). Limited research is done on the activities of small-scale mining in Namibia which results in unavailability of data. Although recent studies reveal that about 5 000 to 10 000 Namibians work as small-scale miners, information about mining activities in Namibia remain a rare commodity. Small-scale ...
ABSTRACT Volcanic and sedimentary rocks of the Sinclair Supergroup occur in the Konkiep Terrane of Southern Namibia. Three volcanic and sedimentary cycles are recognised. The Barby Formation belongs to the second cycle which consists of the Kunjas Formation, Barby Formation and the Guperas Formation. In this work, the volcanic rocks of the Barby Formation, a key unit in the Sinclair area are described and dated. The coeval Spes Bona Syenite and the Tiras Granite are also described and dated. ...
Abstract Knowledge of groundwater age / residence time in Okongo perched aquifer is important in understanding key issues in the evolution of groundwater, recharge rates, recharge mechanisms, resource renewability, flow rate and distribution of recharge areas. The build-up in the atmosphere of trace gases such as sulfur hexafluoride (SF6) and tritium (3H) from over a centenary ago offers a convenient way of dating groundwater up to the age of 60 years. These gases are well mixed in the atmosp...
Geogenic groundwater pollution in volcanic rock aquifer systems on the eastern, western and northern flanks of mount Meru, Tanzania – special reference to fluoride
ABSTRACT Namibia has been known as water-scarce, attributing mostly to its geographic location and primarily because of the limited surface water as well as the high potential evaporation rates beyond 2000 mm/year. Groundwater therefore quickly becomes crucial, most of which is located in aquifers in the savannah biome which covers a large part of the country. This is also where most industrialization, as well as most farming, is practised. It is however unknown how these savannah aquifers ...