Volcanism and geochemistry of soil and vegetation cover of Kamchatka. Communication 2. Specificity of forming the elemental composition of volcanic soil in cold and humid conditions

Volcanic soils of Kamchatka have the low contents of most the chemical elements in relation to their overall prevalence in the soils of continents and volcanic soils of Europe. Relatively increased gross contents of elements typical for volcanic rocks of medium and basic composition: Na, Ca, Mg, Cd, Mn, Co, Cu, and steadily low contents of elements characteristic of acid volcanics: La, Ce, Pr, Nd, Nb, Hf, Tl, Rb and Th, is most characteristic of the soils of different areas of the peninsula. The existing in the past and currently observed different conditions of volcanism in the previously allocated soil areas of Kamchatka determine the diversity of the chemical composition of the soils in these territories.

Volcanism and geochemistry of soil and vegetation cover of Kamchatka. Communication 2. Specificity of forming the elemental composition of volcanic soil in cold and humid conditions

Volcanic soils of Kamchatka have the low contents of most the chemical elements in relation to their overall prevalence in the soils of continents and volcanic soils of Europe. Relatively increased gross contents of elements typical for volcanic rocks of medium and basic composition: Na, Ca, Mg, Cd, Mn, Co, Cu, and steadily low contents of elements characteristic of acid volcanics: La, Ce, Pr, Nd, Nb, Hf, Tl, Rb and Th, is most characteristic of the soils of different areas of the peninsula. The existing in the past and currently observed different conditions of volcanism in the previously allocated soil areas of Kamchatka determine the diversity of the chemical composition of the soils in these territories.

Schoenus rupicola: a narrowly endemic species distinguished from S. melanostachys (Cyperaceae, Schoeneae) in eastern Australia

Widespread, common species are of limited value for regional biogeographic studies and of least concern for conservation and land management. In contrast, narrow endemics may be informative for such studies and are usually of high conservation priority. A new species is separated from the widespread species Schoenus melanostachys on the basis of phenetic analysis of morphological data, and integrating evidence from culm anatomy, culm and fruit ornamentation, and corroborated by ecological differentiation. Schoenus rupicola Musili & J.J.Bruhl is found on acid volcanics of south-eastern Queensland and north-eastern New South Wales, adding yet another narrow endemic to the suite of species that characterises the McPherson Range and associated igneous outcrops.

Geochemistry of the felsic metavolcanic rocks of the Wakeham Group: a metamorphosed peralkaline suite from the eastern Grenville Province, Quebec, Canada

The Wakeham Group is a suite of low-grade (greenschist facies) rocks located in the eastern Grenville Province. In order of volumetric importance, it consists of sandstones, acid volcanics, and gabbro dykes and sills. This report deals with the acid volcanic member of the group. Primary textural features have in large part been preserved. The minerals present include stilpnomelane, white mica, albite, titanite, and zircon. Calculations using 33 chemical analyses show that 29 of the compositions have normative corundum. The rocks would therefore appear to be predominantly peraluminous; however, incompatible trace-element data show affinities with other anorogenic, peralkaline suites. It is proposed that alkali loss, probably during the subsequent Grenvillian orogeny, imposed a peraluminous composition on originally peralkaline rocks. The Wakeham Group cannot be definitively correlated with other metavolcanic rocks found in the region.