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Articles 61 - 90 of 127

Full-Text Articles in Geology

Phytoremediation Potential Of Four Heavy Metals In Soil By Chromolaena Odorata (L.) King & Robinson At The Phytotoxicity Screening Benchmarks, Gloria O. Omoregie, Beckley Ikhajiagbe, Geoffery O. Anoliefo Dec 2019

Phytoremediation Potential Of Four Heavy Metals In Soil By Chromolaena Odorata (L.) King & Robinson At The Phytotoxicity Screening Benchmarks, Gloria O. Omoregie, Beckley Ikhajiagbe, Geoffery O. Anoliefo

Tanzania Journal of Science

The remediative capacity of Chromolaena odorata with respect to heavy metal induced growth-stress was investigated. This was with a view to providing information on the adaptive mechanisms adopted by the test plant during the phytoremediation of selected heavy metals such as copper, manganese, zinc and cadmium. Stems of C. odorata were planted in soils polluted with  Mn, Zn, Cd, and Cu at the ecological screening benchmark (ESB) of 50 mg/kg (Mn and Zn), 4 mg/kg (Cd) and 100 mg/kg (Cu) of metal per kilogram of soil, in varying concentrations of 0 ESB (control), 1 ESB, 3 ESB and 5 ESB. …


Quantitative Assessment Of Resistivity Anisotropy In Evaluation Of Laminated Shaly Sand Hydrocarbon Reservoirs–A Case Study In The Barents Sea, Norway, Ernest S. Mulaya Dec 2019

Quantitative Assessment Of Resistivity Anisotropy In Evaluation Of Laminated Shaly Sand Hydrocarbon Reservoirs–A Case Study In The Barents Sea, Norway, Ernest S. Mulaya

Tanzania Journal of Science

Resistivity anisotropy in shaly sand lamination sequences affects the hydrocarbon evaluation in multiple dimensions of petrophysical logs. Currently, vertical resistivity (Rv) and horizontal resistivity (Rh) from 3D triaxial induction measurements can be applied simultaneously to resolve these petrophysical impacts. In this paper, an extensive analysis is offered with a focus on the hydrocarbon evaluation based on advanced petrophysical logs from a well. A critical analysis is done on the three comparable cases including clean formation as a base case, shaly sand case and laminated shaly sand case towards resolving resistivity anisotropy in a typical shaly sand laminated reservoir. The analysis …


Multivariate Assessment Of Metal Contamination In Mtoni Sedimentary Environment, Tanzania, Matobola Mihale Aug 2019

Multivariate Assessment Of Metal Contamination In Mtoni Sedimentary Environment, Tanzania, Matobola Mihale

Tanzania Journal of Science

Enrichment factor, geo-accumulation factor, contamination factor, degree of contamination, modified degree of contamination and potential contamination index were applied to assess the contamination of metals (Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd and Pb ) in the Mtoni estuary sediments in Dar es Salaam, Tanzania. The sediment samples were sampled as appropriate, treated using established methods and analysed using inductively coupled plasma-high resonance mass spectrometry. The calculated enrichment factor values indicated contamination varying from minor (EF > 1) to severe contamination (EF > 50). The determined geo-accumulation index, contamination factor, degree of contamination, modified degree of contamination and potential contamination …


Geological Modeling Of Hydrocarbon Reservoir Rocks In The Mafia Basin, Offshore Tanzania, Bahati Mohamed, Elisante Mshiu, Ernest Mulaya Aug 2019

Geological Modeling Of Hydrocarbon Reservoir Rocks In The Mafia Basin, Offshore Tanzania, Bahati Mohamed, Elisante Mshiu, Ernest Mulaya

Tanzania Journal of Science

This study presents a 3D geological model of reservoir rocks in the Mafia Basin based on interpretation of 2D seismic and well data towards understanding the hydrocarbon prospectivity. 2D seismic data were used to generate surface maps and therefore the subsurface configuration of the reservoir complemented with petrophysical analysis to determine lithology and reservoir properties. Structural and petrophysical properties modeling were distributed stochastically within the constructed 3D grid using Sequential Indicator Simulation (SIS) and Gaussian Random Function Simulation (GRFS) algorithms. Results from well log analysis and petrophysical models classify the reservoir under a moderate reservoir quality with 19% to 20% …


Assessment Of The Effect Of Acid Activation Of Kaolin From Malangali On Water Defluoridation, Hosea Shuma, Lupituko Mkayula, Yahya Makame Aug 2019

Assessment Of The Effect Of Acid Activation Of Kaolin From Malangali On Water Defluoridation, Hosea Shuma, Lupituko Mkayula, Yahya Makame

Tanzania Journal of Science

Malangali kaolin clay was activated by means of an acid for defluoridation studies. The Acid Activated Malangali Kaolin (AAMK) clay and the Untreated Malangali Kaolin (UMK) were both characterized using spectroscopic and adsorption techniques. BET analysis of AAMK and UMK showed that both clays have mesoporosity characteristics with surface areas ranging from 55 to 58 m2/g. Spectroscopic studies showed that in both clays the major mineral forms are kaolinites and albites with high amounts of SiO2 and Al2O3. AAMK and UMK are endowed with surface functional groups such as OH, Si–O–Si, and Al–O–Al all of which being suitable for adsorption …


The Efficacy Of Raw Malangali Kaolin Clay In The Adsorptive Removal Of Cadmium And Cobalt Ions From Water, Nyemaga Masanje Malima, Esther Hellen Lugwisha, Alinanuswe Simon Mwakaboko Jul 2018

The Efficacy Of Raw Malangali Kaolin Clay In The Adsorptive Removal Of Cadmium And Cobalt Ions From Water, Nyemaga Masanje Malima, Esther Hellen Lugwisha, Alinanuswe Simon Mwakaboko

Tanzania Journal of Science

The suitability of raw Malangali kaolin (RMK) clay for the removal of cadmium and cobalt ions from water was investigated using a batch technique whereas the characterization of adsorbent material was performed by XRD, XRF, ATR-FTIR and N2 physisorption techniques. Various experimental parameters were tested for the effectiveness of RMK in removing heavy metals whereby quantitative determination of both Cd2+ and Co2+ ions has shown that, the factors such as adsorbent particle size, solution pH, contact time, adsorbent dose as well as initial metal ion concentration had significant effects on the adsorption processes. The equilibrium data described by Langmuir and …


Preliminary Sedimentology And Stratigraphy Of The Enigmatic Middle Lake Beds Succession (Pleistocene?) In The Rukwa Rift Basin, Tanzania, Cassy Mtelela May 2018

Preliminary Sedimentology And Stratigraphy Of The Enigmatic Middle Lake Beds Succession (Pleistocene?) In The Rukwa Rift Basin, Tanzania, Cassy Mtelela

Tanzania Journal of Science

This paper presents sedimentology and stratigraphic overview of a series of previously unrecognized lithostratigraphic unit in the Rukwa Rift Basin, Tanzania. Based on the cross-cutting relationship and pilot detrital zircon geochronology, these isolated, enigmatic strata are herein informally termed the middle Lake Beds (mLB). Facies analysis reveals that the mLB units were deposited within a complex array of depositional environments, ranging from alluvial to fluvial channels, floodplains and shallow lakes.  The mLB are characterised herein as isolated outcrop exposures with uncertain age relationships, but which can be divided into five distinctive lithostratigraphic units herein identified as informal members (A-E). These …


Indoor Radon Concentration Levels And Annual Effective Doses For Residence Of Houses Near Uranium Deposit In Bahi District, Dodoma, Tanzania, Najat K. Mohammed, Erasto Focus May 2018

Indoor Radon Concentration Levels And Annual Effective Doses For Residence Of Houses Near Uranium Deposit In Bahi District, Dodoma, Tanzania, Najat K. Mohammed, Erasto Focus

Tanzania Journal of Science

The objective of this study was to determine the levels of indoor radon concentration in houses in Bahi District situated in the neighbourhood of uranium deposit. The study aimed also to assess the annual effective dose due to indoor radon exposure to individuals residing in the houses as a step to control the radon exposure in Tanzania. Two villages were involved in this study; Bahi Makulu, which is within the proximity of Uranium deposit and Bahi Sokoni, which is about 7 km from the deposit. The Indoor radon concentration levels were detected using Alpha Guard radon monitor and the obtained …


Assessment Of Indoor Radon-222 Concentrations In The Vicinity Of Manyoni Uranium Deposit, Singida, Germana W Mlay, Ismael N Makundi May 2018

Assessment Of Indoor Radon-222 Concentrations In The Vicinity Of Manyoni Uranium Deposit, Singida, Germana W Mlay, Ismael N Makundi

Tanzania Journal of Science

This study aimed to assess indoor radon concentrations in the vicinity of the Manyoni Uranium Deposit in Singida. The concentrations were measured for two months in 32 houses in the vicinity of Manyoni Uranium Deposit and 9 houses at Manyoni town using a portable radon gas monitor (Alpha –GUARDTM). The radon concentrations ranged from 27±3 to 518±28 Bq/m3with the overall mean of 166±12 Bq/m3 which is above recommended values of 100 Bq/m3 and 148 Bq/m3 set by WHO (World Health Organization) and EPA (Environmental Protection Agency's), respectively. The overall mean of indoor radon concentrations from each village were Kipondoda (169±13 …


Structural Classification Using Aeromagnetic Data And Pseudogravity Transforms: A Case Study Of Pategi Area Of Bida Basin, Nigeria, Ayodele K Olawuyi, Halima M Amir, Mkabwa Lk Manoko Apr 2018

Structural Classification Using Aeromagnetic Data And Pseudogravity Transforms: A Case Study Of Pategi Area Of Bida Basin, Nigeria, Ayodele K Olawuyi, Halima M Amir, Mkabwa Lk Manoko

Tanzania Journal of Science

The structural classification with 3D Euler deconvolution method in the Pategi area, a transition environment between the Basement complex rocks of the southwestern Nigeria and the Sedimentary rocks of the Nupe Basin was carried out. It was aimed at identification of the structural features responsible for the hydrogeology and mineralization potentials of the area. This work involves the qualitative and quantitative analysis of aeromagnetic data and pseudogravity transforms using Oasis MontajTM. The 3-D Euler deconvolution of the acquired aeromagnetic data and pseudogravity transforms using Oasis montajTM software and the geologic information on this area was employed in the structural classification …


Speciation Of Lead, Chromium, Cadmium, Copper And Zinc In Sediments And Plants Along Msimbazi River In Dar Es Salaam, Tanzania, Faustin N Ngassapa, Othman C Othman, David Mihayo, Kessy F Kilulya Apr 2018

Speciation Of Lead, Chromium, Cadmium, Copper And Zinc In Sediments And Plants Along Msimbazi River In Dar Es Salaam, Tanzania, Faustin N Ngassapa, Othman C Othman, David Mihayo, Kessy F Kilulya

Tanzania Journal of Science

The speciation of lead, chromium, cadmium, copper and zinc in sediments and plants (pumpkin) along Msimbazi River in Dar es Salaam were determined using Atomic Absorption Spectrophotometry.  Results in sediments indicated that the heavy metal contents (mg/kg) in the form of total trace metals ranged from 50.34 to 161.63 for Pb, 68.38 to 501.85 for Zn, 18.43 to 66.61 for Cu, 20.93 to 76.46 for Cr and BDL to 0.23 for Cd. The contents (mg/kg) in the form of metals bound to organic matter ranged from 18.24 to 46.58 for Pb, 27.64 to 228.62 for Zn, 3.55 to 16.76 for …


Assessment Of Radioactivity Levels In Coal And Coal Ash In Kiwira Coal Mine Using Gamma-Ray Spectrometry, Ismael N Makundi, Mungubariki M Nyaki, Najat K Mohammed Apr 2018

Assessment Of Radioactivity Levels In Coal And Coal Ash In Kiwira Coal Mine Using Gamma-Ray Spectrometry, Ismael N Makundi, Mungubariki M Nyaki, Najat K Mohammed

Tanzania Journal of Science

This study aimed to assess the radioactivity levels and associated dose rates from the naturally occurring radionuclides 226Ra, 232Th and 40K in coal and coal ashes at Kiwira coal mine. The radioactivity of 40 representative coal, fly ash samples were measured using gamma spectroscopy of the Tanzania Atomic Energy Commission (TAEC) in Arusha, Tanzania. The activity concentrations of 226Ra, 232Th and 40K in coal and coal ashes from Kiwira were higher by several orders of magnitude than their worldwide average values. The calculated radium equivalent activity, the air absorbed dose rate, external hazard index and the average annual effective dose …


Petrographic And Geochemical Characteristics Of The Kiejo, Rungwe And Ngozi Volcanic Rocks, Southern Tanzania: Implication For Tectonic Activities And Magmatic Differentiation, Athanas S. Macheyeki Jul 2016

Petrographic And Geochemical Characteristics Of The Kiejo, Rungwe And Ngozi Volcanic Rocks, Southern Tanzania: Implication For Tectonic Activities And Magmatic Differentiation, Athanas S. Macheyeki

Tanzania Journal of Science

Rock samples were collected from the Kiejo, Rungwe and Ngozi volcanoes, southern Tanzania. Results show that, in the Ngozi and Rungwe volcanoes, magma cooled relatively fast. After large part of the magma had crystallized, nucleation of crystals at a relatively slow rate crystallized from interstitial fluids of the primary magma that had already crystallized fine grained minerals resulting into large grains of minerals. In the Kiejo volcano, both zoned and unzonned olivine crystals exist; unzoned crystals being primary and the zoned ones are secondary. Such observations also indicate that the magma responsible for these rocks had interstitial fluids that crystallized …


Establishment Of Background Radiation Dose Rate In The Vicinity Of The Proposed Manyoni Uranium Project, Singida, Joyce Elisadiki, Ismael Makundi Jul 2015

Establishment Of Background Radiation Dose Rate In The Vicinity Of The Proposed Manyoni Uranium Project, Singida, Joyce Elisadiki, Ismael Makundi

Tanzania Journal of Science

The absorbed dose rate in air in the vicinity of the proposed Manyoni uranium mining project located in Singida region, Tanzania, was determined so as to establish the baseline data for background radiation dose rate data prior to commencement of uranium mining activities. Twenty stations in seven villages were selected and monitored for six months from June 2012 to November 2012. The absorbed dose rate in air was measured by means of CaF2:Dythermoluminescent dosimeters (TLD-200). The annual effective dose was estimated using outdoor occupancy factor of 0.2 and conversion coefficient  factor of 0.7 SvG y-1. The mean dose rate was …


Assessment Of Heavy Metal Concentration In Water Around The Proposed Mkuju River Uranium Project In Tanzania, Firmi P. Banzi, Peter K. Msaki, Najat K. Mohammed Jul 2015

Assessment Of Heavy Metal Concentration In Water Around The Proposed Mkuju River Uranium Project In Tanzania, Firmi P. Banzi, Peter K. Msaki, Najat K. Mohammed

Tanzania Journal of Science

Effective verification for compliance with water quality standards in uranium mining in Tanzania requires data sensitive to monitor heavy metal concentration in water around the Mkuju River Uranium Project before mining commences. The area susceptible for pollution by the project was estimated using AERMOD dispersion model and found to cover about 1300 km2. Thirty one surface and groundwater samples were collected and analysed for heavy metals and physicochemical properties using ICP-MS and standards techniques, respectively. The physicochemical properties for water samples analysed ranges from 5.7 to 7.8 for pH, 2.8 to 80.2 mg/L for TDS and 15 to 534.5 mS/cm …


Determination Of Radon Gas And Respirable Ore Dust Concentrations In The Underground Merelani Tanzanite Mines, Evarist M. Kahuluda, Ismael N. Makundi Nov 2014

Determination Of Radon Gas And Respirable Ore Dust Concentrations In The Underground Merelani Tanzanite Mines, Evarist M. Kahuluda, Ismael N. Makundi

Tanzania Journal of Science

This study has estimated the concentrations of radon gas and respirable ore dust in the Merelani underground tanzanite mines. Two different portable monitors were used to measure the radon gas and respirable ore dust concentrations, respectively. The mean radon gas concentrations (disintegrations per second per cubic meter) ranged from 40.1 Bq/m3 to 4.2 x 103 Bq/m3 with the geometric mean of 118.4 Bq/m3 which is below the ICRP workplace guidance level of 500 - 1500 Bq/m3. The estimated mean annual effective dose (D) was 1.6 mSv which is significantly lower than the external exposure annual effective dose of 20 mSv …


Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha Nov 2014

Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha

Tanzania Journal of Science

This study analyzed variability in body shapes among the small Barbus species of the family Cyprinidae currently occurring in the Malagarasi and Pangani River basins years after uplift of the east African topology. Fish specimens were collected from Songati, Muumbara and Nyamagoma within the Malagarasi River basin; Hale and Pangani fall located on Pangani River. It was found that although the landmarks were placed at the same anatomical regions, significant body shapes variations existed. The relative warps analysis for Barbus trimaculatus and Barbus jacksonii populations from Malagarasi and Pangani wetlands revealed intra-locality variations as for populations from other African countries. …


Population Dynamics Of Pseudo-Nitzschia Species (Bacillariophyceae) In The Near Shore Waters Of Dar Es Salaam, Tanzania, Charles Lugomela Jul 2013

Population Dynamics Of Pseudo-Nitzschia Species (Bacillariophyceae) In The Near Shore Waters Of Dar Es Salaam, Tanzania, Charles Lugomela

Tanzania Journal of Science

The genus Pseudo-nitzschia is a chain-forming diatom comprising about 30 species some of which are known to produce domoic acid (DA) that causes amnesic shellfish poisoning (ASP). The current study aimed at assessing the population dynamics of Pseudo-nitzschia in the near shore waters of Dar es Salaam. Samples were collected between August 2008 and July 2009 from two stations. The first station was located in the open waters off Mbudya Island and the second was located at a point in-between Kunduchi and Mbudya Island. Three Pseudo-nitzschia species, i.e., Pseudo-nitzschia pungens, Pseudo-nitzschia seriata and Pseudo-nitzschia cuspidata were encountered with Pseudo-nitzschia pungens …


Theoretical Study Of Physiochemical Properties Of Insulin-Like Growth Factor 1, A Ilkhani Dec 2012

Theoretical Study Of Physiochemical Properties Of Insulin-Like Growth Factor 1, A Ilkhani

Tanzania Journal of Science

The computational approach to studying structural changes in a wide range of physical and biological problems, the empirical force fields, have great difficulty in simulating folding of Insulin-like Growth Factor 1 (IGF-1). In an effort to understand the conformational preferences that may be attributed to stereoelectronic effects, a number of computational studies were carried out. Monte Carlo, Molecular Dynamics and Langevin simulation methods by MM+, AMBER and OPLS force fields of calculations have been performed on IGF-1 as growth factors. The parameters of a minimized structure of IGF-1, calculated potential energy for important dihedral angles and the effect of temperature …


Salt Lakes Of The African Rift System: A Valuable Research Opportunity For Insight Into Nature’S Concenrtated Multi-Electrolyte Science, Jyn Philip, Dms Mosha Dec 2012

Salt Lakes Of The African Rift System: A Valuable Research Opportunity For Insight Into Nature’S Concenrtated Multi-Electrolyte Science, Jyn Philip, Dms Mosha

Tanzania Journal of Science

The Tanzanian rift system salt lakes present significant cultural, ecological, recreational and economical values. Beyond the wealth of minerals, resources of these rift salt lakes include unique wildlife, for instance Lesser Flamingo (Phoenicopterus minor) and Cichlids (Alcolapia spp), which adapted chemically aggressive environments like that of Lake Natron. The general hydrochemical equilibria of these salt lakes is governed by Na+ > K+ >> Ca2+ ~ Mg2+ : (CO32- + HCO3-) > Cl- > SO42-~ F- ionic concentration pattern. Salt accumulation mechanism in these endorheic lakes is considered to base on thermo-mechanical disintegrative stress of the geochemistry sourcing. The rains chemically interact with rift terrains, …


Biorecognition Ability Of Polysaccharides As Piezo Quartz Biosensors, En Kalmykova, Ca Mgina Dec 2012

Biorecognition Ability Of Polysaccharides As Piezo Quartz Biosensors, En Kalmykova, Ca Mgina

Tanzania Journal of Science

Piezoquartz biosensors (PQB) which are analytical devices for recognition of biochemical interactions have recently attracted increasing interest from different researchers such as analysts, immune-chemists, medical doctors, environmentalists, etc. This is due to the advantages of PQB for having high detection sensitivity (at ng and mg level depending on the mass of sorbates or micro-organisms) and the ability to monitor biochemical reactions in turbid or highly coloured liquids (including in biological fluids) in real time. The use of additional markers and preliminary sample preparation are not required in this biorecognition process. This paper reports on the principle of the PQB and …


Ni Mineralization And Pge Characterization In The Kabanga And Luhuma Ni-Cu Sulfide Deposits, North West Tanzania, As Macheyeki Jul 2012

Ni Mineralization And Pge Characterization In The Kabanga And Luhuma Ni-Cu Sulfide Deposits, North West Tanzania, As Macheyeki

Tanzania Journal of Science

Nickel mineralization in the Kabanga sulfide ores is found associated with (1) peripheral veins in the country-rock metapelites, (2) contact type massive sulfide mineralization, and (3) disseminated and vein mineralization. This work, apart from giving general highlight of the Ni mineralization (and other associated elements) in the Kabanga and Luhuma, intends to assess the PGE content in both areas. Cores (mafic-ultramafic and metasedimentary rocks as well as ore sections) from both Kabanga and Luhuma areas were sampled, cut, crushed, pulverized and analyzed for both major and trace elements. Results show that all the Iridium Platimum Group Elements (IPGEs) have very …


Paleoseismic Investigations Along The Bubu Fault, Dodoma-Tanzania, As Macheyeki, D Delvaux, Md Batist, A Mruma Jul 2012

Paleoseismic Investigations Along The Bubu Fault, Dodoma-Tanzania, As Macheyeki, D Delvaux, Md Batist, A Mruma

Tanzania Journal of Science

The central part of Tanzania, Dodoma, was hit by an Mw= 5.5 earthquake in November 4, 2002. It was part of a swarm of moderate earthquakes that affected the area. This paper, reports the first attempt to investigate significant past earthquakes along one of the known seismically active riftfaults (Bubu fault, Gonga segment) by paleoseimological trenching. The trench revealed over 3 episodes of faulting (2 of which correspond to Mid-Holocene faulting). The magnitude of the largest earthquake illustrated in the trench is estimated at Mw = 6.3-6.4 and the slip rate between two recent faulting events is about 0.11 to …


Spectral Analysis Of Ground Magnetic Data In Magadi Area, Southern Kenya Rift, Jg Githiri, Jp Patel, Jo Barongo, Pk Karanja Mar 2012

Spectral Analysis Of Ground Magnetic Data In Magadi Area, Southern Kenya Rift, Jg Githiri, Jp Patel, Jo Barongo, Pk Karanja

Tanzania Journal of Science

The area surrounding Lake Magadi in the southern Kenya rift is characterized by hot springs that issue from fractures distributed along the shores of the lake. Presence of earthquake swarms that cluster in northern margin of Lake Magadi strongly indicate magmatic activity in the area. This study was done as a follow-up to investigate depth to the heat source possibly causing high seismic activity and high heat flow in the area. A ground magnetic survey was conducted to investigate geothermal potential of the area and a magnetic anomaly contour map prepared. Spectral analysis involving determining power spectrum was applied to …


Mg-Rich Metabasalts From The Southern Musoma –Mara Greenstone Belt: Possible Evidence For Mantle Plume Activity In The Tanzania Craton?, S Manya Mar 2012

Mg-Rich Metabasalts From The Southern Musoma –Mara Greenstone Belt: Possible Evidence For Mantle Plume Activity In The Tanzania Craton?, S Manya

Tanzania Journal of Science

Mg-rich metabasalts from the Simba Sirori to Majimoto segment of the southern Musoma-Mara greenstone belt are the most magnesian lavas reported in the Archaean Tanzania Craton. The lavas yielded a Sm-Nd isochron age of 2768 ± 38 Ma (MSWD = 1.2) and corresponding !Nd(2.7 Ga) values in the range of + 0.66 to + 2.81. The lavas exhibit high MgO contents of up to 16 wt %, Cr (140 – 1590 ppm), Ni (80 – 510 ppm), values which are higher than those of primitive NMORB, but are comparable with those of Archaean komatiitic basalts and modern oceanic plateau basalts. …


Landsat Remote Sensing Data As An Alternative Approach For Geological Mapping In Tanzania: A Case Study In The Rungwe Volcanic Province, South-Western Tanzania, E. E. Mshiu Dec 2011

Landsat Remote Sensing Data As An Alternative Approach For Geological Mapping In Tanzania: A Case Study In The Rungwe Volcanic Province, South-Western Tanzania, E. E. Mshiu

Tanzania Journal of Science

Rungwe Volcanic Province (RVP) is mostly covered by extrusive rocks that overlain the Precambrian basement. The use of Landsat data in this area has revealed the need of effective use of these data in geological mapping programs in Tanzania. Landsat band ratios 5/1, 3/7, 5/7 and 5/4 as well as R: G: B composite images 7:4:1, 7:5:4, 1/3:5/7:3/5 and 4/5:6/7:4/6 played an important role in identifying different rock types in the study area. Ratio images managed clearly to distinguish between mafic and felsic rocks whereby two lithological blocks were identified, Block 1 covers a combination of intrusive and metamorphic rocks …


Evaluation Of Single-Step Steam Pyrolysis-Activated Carbons From Lesotho Agro-Forestry Residues, I. Hapazari, V. Ntuli, W. Parawira Dec 2011

Evaluation Of Single-Step Steam Pyrolysis-Activated Carbons From Lesotho Agro-Forestry Residues, I. Hapazari, V. Ntuli, W. Parawira

Tanzania Journal of Science

Activated carbon has been widely used worldwide as an effective filtration or adsorption material for removing biological and chemical contaminants from drinking water. The potential of producing activated carbon (AC) from local agroforestry residues by single-step steam pyrolysis processes was investigated. The research aims to promote innovative use of local raw materials and relatively low-cost techniques in production of activated carbon. Four varieties of activated carbons from four different agroforestry residues, pine (Pinus contorta) cones (PC), Abies (Abies cilicica) seeds (AS), maple (Acer ginnala) seeds (MS) and peach (Prunus persica) stones (PS), were prepared and evaluated. The ACs were evaluated …


Petrography And Geochemistry Of Mafic Granulites Of The Ubendian Belt: Contribution To Insights Into The Lower Continental Crust Of The Paleoproterozoic, N. Boniface Dec 2011

Petrography And Geochemistry Of Mafic Granulites Of The Ubendian Belt: Contribution To Insights Into The Lower Continental Crust Of The Paleoproterozoic, N. Boniface

Tanzania Journal of Science

Mafic granulites of the Ubendian Belt have geochemical signature, trace and REE patterns, similar to that of the lower continental crustal rocks. A SHRIMP U-Pb single zircon date at 1977±40 Ma indicates that these rocks belong to the Paleoproterozoic Ubendian orogenic cycle, which was followed by the Mesoproterozoic tectonic disturbance that contributed to their exhumation. Orthopyroxene, clinopyroxene, garnet, hornblende, plagioclase and quartz is a frequent mineral assemblage for the mafic granulites of the Ubendian Belt, and garnet frequently form corona between plagioclase and clinopyroxene. Geothermobarometric calculations have revealed the equilibration of these rocks at a temperature range between 650 and …


Contact Metamorphism In The Supracrustal Rocks Of The Sukumaland Greenstone Belt In The North West Tanzania, N. Boniface Dec 2011

Contact Metamorphism In The Supracrustal Rocks Of The Sukumaland Greenstone Belt In The North West Tanzania, N. Boniface

Tanzania Journal of Science

Biotite-granite intrusions in meta-ironstones at Geita Hills and the Bukoli alkali-granite intrusion in metabasites at Mawemeru area produced heat that baked the respective country rocks through epidote-amphibolite- to amphibolite-facies. Critical and informative mineral assemblages in the metairostones of Geita Hills are garnet-grunerite-epidote-quartz and garnetferrogedrite- biotite-quartz and in the metabasites of Mawemeru is ferrotschermakite-(Naplagioclase)- quartz. Peak temperatures ranging between 438°C and 544°C were calculated from the above mineral assemblages and a pressure not exceeding 3 kbar was inferred to from the composition of magnesium-iron amphiboles (grunerite with XFe ratio of 0.83, i.e. Gru83). Hornfels textures in the metaironstones are suggested by …


Serotonin Immunoreactive Cells And Nerve Fibers In The Mucosa Of The Rat Stomach, A P Gesase Jul 2009

Serotonin Immunoreactive Cells And Nerve Fibers In The Mucosa Of The Rat Stomach, A P Gesase

Tanzania Journal of Science

The current study has showed the morphological features of serotonin (5-hydroxytryptamine) immunoreactivity in the pyloric mucosa of the rat stomach. The immunoreactive elements included the endocrine cells, mast cells and mucosal nerve fibers in the lamina propria. The immunopositive endocrine cells were oval in shape and located mostly in the basal part of the gastric glands. The cell contained a central non-staining area and the peripheral staining zone. The mast cells stained homogenously and appeared to be oval-round in shape. They were located in the upper, middle and basal parts of the mucosa. Serotonin immunoreactive nerve fibers with varicosities were …