Organic and trace elements geochemistry of western Niger delta oils

Author(s):  
J Nwachukwu ◽  
A Mustafa
Keyword(s):  
2017 ◽  
Vol 36 (2) ◽  
pp. 130-135 ◽  
Author(s):  
Oluwabamise L. Faboya ◽  
Abiodun A. Ojo ◽  
Hafsat Bello ◽  
Ilesanmi Osasona

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
S. O. Oni ◽  
A. S. Olatunji ◽  
O. A. Ehinola

Provenance analysis serves to reconstruct the predepositional history of a sediment/sedimentary rock. This paper focuses on the reconstruction of the provenance and tectonic settings of the Niger delta clastic facies using geochemical approach. The main types of geochemical tests include major, trace, and rare earth element (REE) tests. Twenty-one samples of shales and sandstones units were purposely collected from a depth between 1160 and 11,480 m, grinded, pulverized, and sieved with a <75 μm. About 5 g was packed and sent to Acme analytical Laboratory Ltd., Vancouver, Canada. The analyses were carried out by both induced coupled plasma-mass spectrometry (ICP-MS) and induced coupled plasma-emission spectrometry (ICP-ES). Bulk-rock geochemistry of major oxides, trace elements, and rare earth elements was utilized for the provenance and tectonic setting determination. Based on the discrimination diagram for major oxides, the probable provenance of the south eastern Delta clastic sediments was mainly of the active continental margins. The bivariate plots of La versus Th, La/Y versus Sc/Cr, and Ti/Zr versus La/Sc and the trivariate plots of La-Th-Sc, Th-Sc-Zr/10, and Th-Co-Zr/10 are all plotted on the fields of active continental margin sediments which is consistent with the known actively opening of a failed arm of triple junction. The trace elements and REE analysis indicates that they are virtually Fe-rich, lithic/quartz arkosic sandstones. The normalizing factors used for the REE are Wakita chondrite. Their rare earth elements (REE) pattern displays high light REE/heavy REE (LREE/HREE) ratio, flat HREE, and a significant negative Eu anomaly which correlate well with the UCC and PAAS average composition. The source area may have contained felsic igneous rocks.


2020 ◽  
Vol 26 (2) ◽  
pp. 141-155
Author(s):  
Florence O. Amiewalan ◽  
Frankie .O. Balogun ◽  
Kingsley Ejairu

The sedimentology and geochemistry of the major oxides and trace elements of DF-2 well, Onshore, Niger Delta, are presented in this study. The study is aimed at describing the sedimentological characteristics as well as using the major oxides and trace elements to investigate the provenance, tectonic history and palaeo-depositional conditions of the well. Selected samples were investigated with fused bead X-Ray Fluorescence (XRF) spectrometry to determine their major oxides and fused bead laser ablation inductively couple plasma mass spectroscopy (LA-ICP-MS) for  their trace elements. Sedimentological analysis from the well shows that the lithology ranged from shaly sand, sandy shale, sandstone and shale. The results show the dominance of silicon oxide (SiO2) contents which ranges from 81.1 to 91.4 wt. % (average of 87.1 wt. %). The low average concentration of Cr<150 ppm and Ni <100 ppm, the ratios of Th/Sc, Th/Co, Th/Cr, Cr/Th, La/Sc, as well as the plots of Th/Co versus La/Sc and TiO2 versus Zr, all infer a felsic source rock. The discrimination plots of ratioK2O/Na2O against SiO2 and Log K2O/Na2O against Log SiO2/Al2O3 indicated passive continental margin. Various chemical classifications of the sediments show that the sandstone facies plotted mainly in quartzarenite, sublitharenite and Fe-rich sand domains. The samples were deposited under oxic environment based on the average values of U/Th (0.26 ppm), Ni/Co (2.79 ppm) and Cu/Zn (1.81ppm) and bivariate plot of Ni/Co versus V/Cr. However, the bivariate plot of Ni/Co versus V/ (V+Ni) specifies oxic to  anoxic conditions and V/Vi + Ni ratios indicate oxic, suboxic to euxinicpalaeode positional environments for the sediments. Geochemical characterization illustrates mixed marine and terrigenous source input, deposited mainly in semi humid/humid climate. The positive values attained from ratios of Al2O3/(CaO+MgO+Na2O+K2O) infers mineralogical maturity based on stable mobile oxides content in the studied samples. Keywords: Felsic Rock, Quartzarenite, Litharenite, Passive Margin, Mobile Oxide, Mature Sediments.


Author(s):  
O.T. Woo ◽  
G.J.C. Carpenter

To study the influence of trace elements on the corrosion and hydrogen ingress in Zr-2.5 Nb pressure tube material, buttons of this alloy containing up to 0.83 at% Fe were made by arc-melting. The buttons were then annealed at 973 K for three days, furnace cooled, followed by ≈80% cold-rolling. The microstructure of cold-worked Zr-2.5 at% Nb-0.83 at% Fe (Fig. 1) contained both β-Zr and intermetallic precipitates in the α-Zr grains. The particles were 0.1 to 0.7 μm in size, with shapes ranging from spherical to ellipsoidal and often contained faults. β-Zr appeared either roughly spherical or as irregular elongated patches, often extending to several micrometres.The composition of the intermetallic particles seen in Fig. 1 was determined using Van Cappellen’s extrapolation technique for energy dispersive X-ray analysis of thin metal foils. The method was employed to avoid corrections for absorption and fluorescence via the Cliff-Lorimer equation: CA/CB = kAB · IA/IB, where CA and CB are the concentrations by weight of the elements A and B, and IA and IB are the X-ray intensities; kAB is a proportionality factor.


Author(s):  
D. A. Carpenter ◽  
Ning Gao ◽  
G. J. Havrilla

A monolithic, polycapillary, x-ray optic was adapted to a laboratory-based x-ray microprobe to evaluate the potential of the optic for x-ray micro fluorescence analysis. The polycapillary was capable of collecting x-rays over a 6 degree angle from a point source and focusing them to a spot approximately 40 µm diameter. The high intensities expected from this capillary should be useful for determining and mapping minor to trace elements in materials. Fig. 1 shows a sketch of the capillary with important dimensions.The microprobe had previously been used with straight and with tapered monocapillaries. Alignment of the monocapillaries with the focal spot was accomplished by electromagnetically scanning the focal spot over the beveled anode. With the polycapillary it was also necessary to manually adjust the distance between the focal spot and the polycapillary.The focal distance and focal spot diameter of the polycapillary were determined from a series of edge scans.


1979 ◽  
Vol 7 (6) ◽  
pp. 1330-1331
Author(s):  
E. D. WILLS

2004 ◽  
Vol 74 (4) ◽  
pp. 247-251 ◽  
Author(s):  
Lombardi-Boccia ◽  
Lanzi ◽  
Lucarini ◽  
Di Lullo

This study was undertaken to estimate the contribution of meat and meat products consumption to the daily intakes of trace elements (Fe, Zn, Cu, Se), heme iron, and selected B vitamins (thiamine, riboflavin, niacin) in Italy. Meat and meat products were selected on the basis of their consumption frequency reported by the most recent nationwide dietary individual survey carried out in Italy (INN-CA study). The daily intakes of total iron and heme iron were 1.65 and 1.13 mg/person/day. Zinc intake was 3.65 mg/person/day. Beef made the main contribution to iron, heme iron, and zinc daily intakes. Copper daily intake was 107.3 mug/person/day, with meat products provided the highest contribution (40 mug/person/day). Daily intake of selenium (7.14 mug/person/day) was provided mainly by poultry consumption. Thiamine intake was 228 mug/person/day, and meat products were the main source (110 mug/person/day). Riboflavin intake was 136 mug/person/day, with both beef and meat products as the main contributors (40 mug/person/day). Niacin intake was 7.53 mg/person/day, and poultry was the main source (2.28 mg/person/day). Meat and meat products were a valuable source of micronutrients, supplying 47, 48, and 24% of zinc, niacin, and thiamin daily requirements, respectively, and over 10% of iron, copper, selenium, and riboflavin daily average requirement values of the italian RDAs calculated for the population involved in the survey (INN-CA study).


2003 ◽  
Vol 107 ◽  
pp. 945-948 ◽  
Author(s):  
P. M. Nicolaysen ◽  
E. Steinnes ◽  
T. E. Sjobakk

Sign in / Sign up

Export Citation Format

Share Document