An Olivine-bearing Hornfels from South-Eastern Queensland

1959 ◽  
Vol 96 (5) ◽  
pp. 377-384 ◽  
Author(s):  
E. R. Phillips

AbstractContact metamorphism by a gabbro of an unusual slightly metamorphosed argillite with comparatively high magnesia and total iron has produced an olivine-bearing hornfels. The sediment is of such a chemical composition that an almost isochemical transformation is considered to have taken place. Only Mg shows any significant change from the sediment to the hornfels.

2020 ◽  
Vol 17 (2) ◽  
Author(s):  
Milan D. Ilić ◽  
Mirjana D. Marčetić ◽  
Bojan K. Zlatković ◽  
Branislava S. Lakušić ◽  
Nada N. Kovačević ◽  
...  

2021 ◽  
Vol 22 ◽  
Author(s):  
Rodrigo de Andrade Ferrazza ◽  
Elena Castellani

Abstract In this study, we investigated the principal transformations in dairy farming among Brazilian federative units in the period from 2006 to 2017. Data were drawn from the Agricultural Censuses from 2006 and 2017. In order to compare the variations between the states and macroregions, descriptive analyses were performed. Pearson correlation was used to test the correlation among the variables. A 4.63% decrease was observed in the number of establishments supporting cattle, notably in the states of PE (-23.02%), RS (-20.67%) and PR (-19.65%). Some states showed greater participation in terms of increase in number of cattle, particularly in the Northern region. No significant change in pasture area was observed. A decrease of 12.92% in number of milk producers was observed, mainly in the traditional dairy basins, such as RS (-36.62%), PR (-27.33%), SP (-24.67%) and SC (-20.21%). Producers who continued in the activity had a rise in the scale of their daily production. Although there was a 9.47% reduction in the number of cows milked, the herd productivity showed a 61.96% surge, particularly in the Southern (72.98%) and South-eastern (62.31%) areas. Milk production revealed higher correlation with number of cows milked (P<0.05; r=0.97) and productivity per cow (P<0.05; r=0.63), than with area of the rural establishments (P<0.05; r=0.38). In conclusion, there were significant changes in dairy farming over an eleven-year period, including changes in the geography of production, greater concentration and professionalization of the activity, as well as the expressive growth of milk production in almost every state, which is reflective of higher productivity of the national herd.


1980 ◽  
Vol 11 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Jan Økland

In 50 lakes in south-eastern Norway hydrogen-ion concentration (pH) and total hardness (°dH) were measured in surface water in the 1950's and then once again 10 years later. Significant acidification was observed. In the total material average pH dropped from 7.0 to 6.8. The lakes were grouped into a low-total-hardness (0-l°dH) and a high-total-hardness group (&gt;l°dH). [l°dH = 10 mg »CaO«/l]. In the low-total-hardness group average pH had dropped from 6.6 to 6.3 and the average H+ concentration increased with 4.33. 10−7 mol/1. In the high-total-hardness group significant acidification could hardly be traced. The data confirm previous observations that also lakes which in previous years had pH close to the neutral point have become acidified. Total hardness showed no significant change. Acidification seems to occur most frequently in lakes with total hardness ⩽l°dH. Such lakes are present all over Norway and are dominant in many areas.


2021 ◽  
Author(s):  
Larisa M. Sorokovikova ◽  
Olga Netsvetaeva ◽  
Irina Tomberg ◽  
Yelena Molozhnikova

1969 ◽  
Vol 37 (287) ◽  
pp. 317-332 ◽  
Author(s):  
D. R. C. Kempe

SummaryThe cell parameters of 35 members of the arfvedsonite-eckermannite series and catophorites (17 from the literature, 18 newly determined) are presented and an attempt made to relate them to chemical composition. In general, all parameters (including β, obtuse) decrease from arfvedsonite to eckermannite, but for different reasons: a, b, and β (very slightly) as the Mg: Fe2+ ratio and F increase; c as Fe3+ decreases. The apparent decrease in a and b with high Li is coincidental, due to its strong correlation with F, which varies inversely With (OH). In addition, b is increased by high Ca and slightly reduced by high A1.Also, the empirical and calculated curves relating MgO and total iron as Fe2O3 (weight %) with the Mg ratio, 100 Mg/(Mg + Fe2+ Fe3+ + Mn), for all amphibole groups are given, as a rapid method of obtaining an estimate of the Mg ratio.The full lists of possible hkl values for an arfvedsonite and an eckermannite are enumerated up to 45° 2θ, Cu-Kα, to illustrate the difficulty in indexing X-ray photographs and diffractometer charts of this group.


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