scholarly journals THE ISLAND ARC FERROCORDIERITE-ALMANDINE PLAGIORHYOLITES OF THE MOUNT KASTEL, MOUNTAIN CRIMEA

Author(s):  
E. M. Spiridonov

Plagio rhyolites of the Pre-Late Jurassic dyke contain restitegamet (cribrate inter grow ths of almandinespessartine and quartz) and ferrocordierite. The garnets of such habit and composition and with such kind of zonality - the content of Mg increases and the content of Mn decreases from the center to the edges - are typical for ferriferous metapelites of amphibotite facies. Composition of the rocks, during palingenesis of which the melt of plagiorhyolites of the Mount Kastel formed, probably corresponded to the cordierite-almandine plagiogneisses. An assessment of the parameters of these metamorphic rocks forming according garnet and cordierite compositions is »550° С and 4 kbar, so they are metamorphic rocks of the amphibotite facies of moderate pressure. There is an assumption, that Mountain Crime a tectonic zone was possibly formed on the ancient crystalline basement, on the mature continental crust, possible continuation of the structures of Russian Plattorm to the south. Ferro cordierite - sekaninaite has been described in Crimea for the first time. A part of garnet and cordiertte was replaced by highly ferriferous chlorite (daphnite) and pumpellyite-(Fe), a part of biotite, titanomagnetite and ilmenite - by chlorite, epidote, pumpellyite-(Fe) and mineral with intermediate compotition between titantte and vuagnatite. The reby, plagio rhyoltes were subj ected by metamorphism of prehnite-pumpellyite facies.

2009 ◽  
Vol 4 ◽  
pp. 273-288 ◽  
Author(s):  
S. D. Sokolov ◽  
G. Ye. Bondarenko ◽  
A. K. Khudoley ◽  
O. L. Morozov ◽  
M. V. Luchitskaya ◽  
...  

Abstract. A long tectonic zone composed of Upper Jurassic to Lower Cretaceous volcanic and sedimentary rocks is recognized along the Asian continent margin from the Mongol-Okhotsk fold and thrust belt on the south to the Chukotka Peninsula on the north. This belt represents the Uda-Murgal arc, which was developed along the convergent margin between Northeast Asia and Northwest Meso-Pacific. Several segments are identified in this arc based upon the volcanic and sedimentary rock assemblages, their respective compositions and basement structures. The southern and central parts of the Uda-Murgal arc were a continental margin belt with heterogeneous basement represented by metamorphic rocks of the Siberian craton, the Verkhoyansk terrigenous complex of Siberian passive margin and the Koni-Taigonos Late Paleozoic to Early Mesozoic island arc with accreted oceanic terranes. At the present day latitude of the Pekulney and Chukotka segments there was an ensimatic island arc with relicts of the South Anyui oceanic basin in a backarc basin. Accretionary prisms of the Uda-Murgal arc and accreted terranes contain fragments of Permian, Triassic to Jurassic and Jurassic to Cretaceous (Tithonian–Valanginian) oceanic crust and Jurassic ensimatic island arcs. Paleomagnetic and faunal data show significant displacement of these oceanic complexes and the terranes of the Taigonos Peninsula were originally parts of the Izanagi oceanic plate.


2018 ◽  
Vol 40 (1) ◽  
pp. 31 ◽  
Author(s):  
T. Danelian ◽  
G. Galoyan ◽  
Y. Rolland ◽  
M. Sosson

Micropalaeontological age evidence for the sedimentary cover of ophiolites is important to understand the palaeogeographic and geodynamic evolution of Tethyan realms. The Stepanavan ophiolitic suite of Northern Armenia consists of peridotites, gabbros, plagiogranite and lavas with a radiolarite sedimentary cover. It is regarded as the northern extension of the Sevan Akera ophiolitic zone and may be considered as the eastern extension of the Izmir-Ankara suture zone. It represents the relics of a slow-spreading mid oceanic ridge that was active between Eurasia and the South-Armenian Block of Gondwanian origin. Radiolaria extracted from radiolarites of the Stepanavan ophiolite provide for the first time a Late Jurassic (late Kimmeridgian to early Tithonian) age constraint for this part of Tethyan oceanic crust preserved in Lesser Caucasus.


2017 ◽  
Vol 51 ◽  
pp. 232-241 ◽  
Author(s):  
G. Ya. Doroshina ◽  
E. Yu. Kuzmina ◽  
I. A. Nikolajev

Information on the Sphagnum mosses of the South Ossetia is generalized, the resulted list is presented. Nine species of Sphagnum are included in the list, whereabouts data and references to the publications are given, and the presence of a sample in the Herbarium of the Komarov Botanical Institute RAS (LE) is noted. The species Sphagnum platyphyllum (Lindb. ex Braithw.) Warnst. rarely occurring in the Caucasus is reported in the South Ossetia for the first time. The species was found in the Caucasus, South Ossetia, at the side of the Ertso Lake (42°28ʹN, 43°45ʹE), 1720 m a. s. l., among sedge thickets at the margin of the overgrowing lake. The peculiarities of its occurrence and ecological conditions are considered. Its distribution in the Caucasus and in the world is discussed.


2013 ◽  
Vol 47 ◽  
pp. 215-221 ◽  
Author(s):  
A. B. Ismailov ◽  
G. P. Urbanavichus

49 lichen species and 2 species of non-lichenized saprotrophic fungi are recorded for the first time in beech forests of the south-eastern part of piedmont Dagestan. Among them, 34 species and 9 genera are new to Dagestan Republic, and 2 species, Diplotomma pharcidium (Ach.) M. Choisy and Rinodina albana (A. Massal.) A. Massal., are new to Caucasus Mountains.


2020 ◽  
Vol 29 (1) ◽  
pp. 75-76
Author(s):  
V.B. Golub ◽  
E.V. Sergeeva
Keyword(s):  

The lacebug species Agramma atricapillum (Spinola, 1837) (Heteroptera: Tingidae) is recorded in the Asian part of Russia, namely in the south of the Tyumen’ Province, for the first time.


2021 ◽  
Vol 356 ◽  
pp. 106104
Author(s):  
D.R. Mole ◽  
P.C. Thurston ◽  
J.H. Marsh ◽  
R.A. Stern ◽  
J.A. Ayer ◽  
...  

2003 ◽  
Vol 140 (1) ◽  
pp. 25-30 ◽  
Author(s):  
MARIA A. MANGE ◽  
JOHN F. DEWEY ◽  
DAVID T. WRIGHT

Heavy minerals in Ordovician successions in western Ireland record, in the Upper Arenig Sheeffry Formation, the erosion of an ophiolite/island arc complex. The appearance of staurolite and garnet at a basin-wide horizon in the Lower Llanvirn Upper Derrylea Formation signals the unroofing of the Dalradian metamorphic complex. Parts of the Ordovician sequence on Inishturk and in two small inliers are correlated with the standard sequence with unexpected results. The garnet-, sillimanite-, and staurolite-bearing Letter Formation correlates with the Upper Derrylea Formation and, on Inishturk, heavy minerals in south-younging turbidites reveal a sinistral ramp zone, that places the Sheeffry Formation structurally above and to the south of the younger Derrylea Formation.


Zootaxa ◽  
2021 ◽  
Vol 5071 (4) ◽  
pp. 451-491
Author(s):  
ANDREY I. KHALAIM ◽  
ENRIQUE RUÍZ-CANCINO

Mexican species of three pimpline genera, Apechthis Förster (one  species), Itoplectis Förster (six species) and Pimpla Fabricius (20 species, including one unidentified taxon), are reviewed. Four species of Pimpla are described as new to science: P. chamela sp. nov., P. oaxacana sp. nov., P. tequila sp. nov. and P. xalapana sp. nov. Pimpla thoracica Morley, 1914 is found to be a junior synonym of P. ellopiae Harrington, 1892 (syn. nov.). Apechthis zapoteca (Cresson) is recorded for the first time from Venezuela, Pimpla dimidiata (Townes) from Mexico, P. caeruleata Cresson, P. croceiventris (Cresson), P. sanguinipes Cresson and P. sumichrasti Cresson from Honduras, P. ichneumoniformis Cresson and P. viridescens Morley from Guatemala and Honduras, and P. punicipes Cresson from Panama. The South American species Pimpla caerulea Brullé and the Nearctic species P. pedalis Cresson are excluded from the Mexican fauna. Male of Itoplectis mexicana and female of Pimpla dimidiata are recorded for the first time. Identification keys to the species of Itoplectis and Pimpla occurring in Mexico are provided.  


1975 ◽  
Vol 5 (4) ◽  
pp. 13-20
Author(s):  
Philip E. Chartrand

In December 1974, Ian Smith, the leader of the white minority regime in Rhodesia, announced for the first time since declaring his country’s independence from Britain in 1965 that his government was willing to begin direct negotiations with the African liberation movements seeking to achieve majority rule in Rhodesia. The prospect of such talks leading to an end to guerrilla fighting in Rhodesia and a termination of the United Nations authorized sanctions against the illegal Smith regime is dimmed by the fact that the Africans demand African rule for Rhodesia in the near future if not immediately, while Smith and his supporters have refused to consider such a development “in his lifetime.” Still the announcement constituted a step forward which few informed observers would have deemed likely even a few weeks before.


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