Mantle xenoliths from Tallante (Betic Cordillera): Insights into the multi-stage evolution of the south Iberian lithosphere

Lithos ◽  
2011 ◽  
Vol 124 (3-4) ◽  
pp. 308-318 ◽  
Author(s):  
Gianluca Bianchini ◽  
Luigi Beccaluva ◽  
Geoff M. Nowell ◽  
D. Graham Pearson ◽  
Franca Siena
Lithos ◽  
2004 ◽  
Vol 75 (1-2) ◽  
pp. 67-87 ◽  
Author(s):  
Luigi Beccaluva ◽  
Gianluca Bianchini ◽  
Costanza Bonadiman ◽  
Franca Siena ◽  
Carmela Vaccaro

2014 ◽  
Vol 39 (1) ◽  
pp. 383-397 ◽  
Author(s):  
M. Cassidy ◽  
J. Trofimovs ◽  
S. F. L. Watt ◽  
M. R. Palmer ◽  
R. N. Taylor ◽  
...  

Author(s):  
Andisiwe Diko ◽  
Wang Jun

Aims: Maize is of great significance in the national food security of South Africa. Maize production levels in South Africa continue to decline, further deteriorating the situation of increased food insecurity, unemployment and increased poverty levels in the face of increasing population. This paper investigated fundamental variables influencing maize yield in the South African major maize producing regions. Study Design: A multi-stage stratified sampling method was employed to select maize producing farmers in the major maize producing provinces, namely Mpumalanga, Free State and North West provinces of South Africa. Furthermore, three districts were selected from which maize farmers were then selected. Methodology: Using linear multiple regression for a sample of 202 maize farmers, maize yield as a dependent variable was regressed against land size, fertilizer usage, labour, herbicides and seeds as independent variables. The paper employed the Cobb-Douglas production function to estimate parameters. The data obtained from the field were subjected to analysis using inferential statistics using SPSS v20. Results: The study showed that fertilizer, labour, and herbicides used in the production of maize in the study area were positively and statistically significant at a 5% confidence interval (P<0.05) with elasticity coefficients of 0.55, 0.47 and 0.198 respectively. The independent variables computed in the model had positive elasticity coefficients indicating a direct positive relationship between the input variables and maize output. The study also revealed that farmers in the study area were applying fewer amounts of fertilizer than the recommended rates per hectare. Conclusion: The study recommends that the South African government should supply inputs to maize farmers at subsidized rates to promote correct application rates and attain higher yields.  The promotion of good quality extension services to foster good agricultural practices in the production of maize is also recommended.


2019 ◽  
Vol 10 (5) ◽  
pp. 1941-1959 ◽  
Author(s):  
A.V. Kargin ◽  
L.V. Sazonova ◽  
A.A. Nosova ◽  
N.M. Lebedeva ◽  
Yu.A. Kostitsyn ◽  
...  

2018 ◽  
Vol 472 (472) ◽  
pp. 231-254
Author(s):  
Cezary Sroga ◽  
Wojciech Bobiński ◽  
Wiesław Kozdrój

From 1969 to 1993, investigation for the Ba-F mineralization was executed within the metamorphic Kaczawa complex, north of the Intra-Sudetic Fault in the Jeżów Sudecki-Dziwiszów area (Kaczawa Mts., Western Sudetes). The article presents unpublished results of those prospecting works. A small deposit of Ba-F with Zn, Pb, Cu-sulphides, on the SE slope of the Szybowisko hill near Jelenia Góra, was documented in 1994. The economic mineralization is developed in the Jeżów Sudecki fault, steep fracture zone running parallel to the Intra-Sudetic Fault, and was identified at a distance of 600 m along the strike of the fault (in the W–E direction) and up to a depth of 500 m along the dip (towards the south). Two (locally three) bifurcating veins were found. The average content of the main components is: BaSO4 – 63.18%, CaF2 – 8.60%. The Ba-F mineralization is associated with the Jeżów Sudecki fault, synchronous with the formation of the Intra-Sudetic Fault zone. Both of these faults are Variscan and fall steeply southward. Younger, alpine (?) inverse and transverse normal faults were formed after the intrusion of a rhyolite dyke into the Kaczawa complex rocks and after the formation of the barite deposit. The Ba-F mineralization developed in a multi-stage process and shows a pulsatory nature. Five mineral parageneses were distinguished in the deposit. The age of the Ba-F mineralization has not been definitively established.


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