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Редактор(ы):Wiedmann J.
Издание:E.Schweizerbrat'sche Verlagsbuchhandlung, Stuttgart, 1989 г., 978 стр.
Язык(и)Английский
Cretaceous of the Western Tethys

In 1978, in Munster, the German Subcommission on Cretaceous Stratigraphy initiated a first International Symposium on the Cretaceous. The focus of the symposium was on Germany and Central Europe. The proceedings were published in 1979. The second symposium was held in 1982 in Munich and concentrated on the Alpine Cretaceous. The proceedings were published in 1983.

Published in this volume are proceedings of the third symposium, which took place in Tubingen in 1987 and whose topic was the western Tethys. The participants of the symposium unanimously decided to dedicate the volume published to TOVE BIRKELUND in response to the loss of our highly esteemed Danish colleague.

Том 2
Автор(ы):Doyle P.
Издание:The Paleontolographical Society, London, 1992 г., 62 стр.
Язык(и)Английский
The British Toarcian (Lower Jurassic) Belemnites. Part 2

Part 2 includes descriptions of 13 species belonging to 5 genera (including Simpsonibelus gen. nov. and Brevibelus nom. nov.) of the Belemnitidae d'Orbigny; 3 species belonging to one genus of the Salpingoteuthididae fam. nov.; and one species belonging to one genus of the Belemnoteuthididae Zittel.

Том 1
Автор(ы):Doyle P.
Издание:The Paleontolographical Society, London, 1990 г., 88 стр.
Язык(и)Английский
The British Toarcian (Lower Jurassic) Belemnites. Part 1

Part 1 includes sections on the history of previous research, belemnite morphology and the stratigraphy of the British Toarcian outcrop. Five Toarcian belemnite biozones are proposed  22 species belonging to 4 genera of the Belemnitidae d'Orbigny are described.


Издание:Journal Tectonophysics, 1997 г., 14 стр.
Язык(и)Английский
Platinum-group elements as petrological indicators in mafic-ultramafic complexes of the central and southern Urals: preliminary results / Элементы платиновой группы как петрологический индикатор мафит-ультрамафитовых комплексах центрального и южного Урала

Platinum-group elements (PGE) and gold were analyzed by ICP-MS after the Ni-sulphide fire assay pre-concentration step in 44 rocks from 5 orogenic mafic-ultramafic massifs of the central and southern Urals. They comprise: (a) ring-zoned, Ural-Alaskan type bodies of the 'Pt-bearing belt' (Kachkanar, Tagil, Uktus); and (b) lherzolite-harzburgite complexes overlain by layered wehrlite, gabbro, and diorite (Nurali, Mindyak) supposed to be ophiolite-type suites.

Издание 4
Автор(ы):Lindgren W.
Издание:McGraw-Hill Book Company, New York - London, 1933 г., 930 стр.
Язык(и)Английский
Mineral deposits

Mineral deposits are usually classified and described by the metals or the substances which they contain; for instance, deposits of copper are described together, with little or no effort to separate them into genetic groups. Where a genetic treatment has been attempted it appears to me to have failed in not giving due weight to the physical conditions attending the genesis. Furthermore, it is the custom to divide the mineral deposits into two groups—the metallic and the non-metallic—a line of division which can hardly be defended except on the ground of long-established habit.

Том 28, Выпуск 4
Издание:Journal Geotectonics, 1995 г., 11 стр.
Язык(и)Английский
Romanche fracture zone: Structure, evolution, and geodynamics / Зона разлома Романш: структура, эволюция и геодинамика

This work is based on survey data from the 13th and 16th cruises of the R/V Akademik Nikolai Strakhov. The tectonic structure of the Romanche fracture zone in the Equatorial Atlantic is considered. Based on its dynamics, kinematics and historical evolution, the zone does not seem to be a uniform structure. Its segments are of different age and evolved according to different dynamic and kinematic laws. The fracture zone is not continuous in space: deformations complicating it migrate both along and a cross its strike, creating new fracture zones with somewhat different orientation. Three geodynamic systems are recognized within the fracture zone, namely Rom 1, Rom 2 and Rom 3.   In the eastern junction of the rift and the Romanche fracture zone, the rift valley jumps northward with simultaneous prograding. A "dry" spreading mode is pronounced in the region.

Выпуск 65
Автор(ы):Juvonen R., Kontas E.
Издание:Journal of Geochemical Exploration, 1999 г., 11 стр.
Язык(и)Английский
Comparison of three analytical methods in the determination of gold in six Finnish gold ores, including a study on sample preparation and sampling

We used samples from six Finnish ore deposits to evaluate the efficiency of sample pretreatment procedures — crushing, splitting and grinding — and to compare three analytical methods based on the atomic absorption determination of gold following: (1) classical lead fire assay (FA); (2) the aqua regia leach (AR) followed by Hg coprecipitation of Au; and (3) the sodium cyanide (NaCN) leach. Sample size used for the method comparison is 20 g. The Au deposits and ore types were: Suurikuusikko and Osikonma¨ki, refractory ores in which Au is associated with arsenopyrite and pyrite; Pampalo and Kutemaja¨rvi ores with metallic Au and Au tellurides; and Jokisivu and Pahtavaara ores containing coarse-grained metallic Au. After crushing, the samples were split into three parts, one of which was put aside into storage. Two splits were further divided into two subsamples which were ground to two grades of fineness (<0.03 and <0.06 mm). The four subsamples thus obtained were analysed for Au using the three analytical methods. Each determination was performed five times on each of the four subsamples. According to t-tests on the FA results of the two splits, crushing and splitting produced samples of equal Au content in all six cases. Grinding to a finer grain size gave a significant difference in Au results only for the Pahtavaara ore sample. If the FA results are assumed to represent 100% recovery of Au, we obtained greater than 95% recoveries for all but the Suurikuusikko sample (87% recovery) by the AR leach method. We also obtained recoveries of over 95% by the NaCN leach method for the Pampalo, Kutemaja¨rvi and Pahtavaara samples, whereas recoveries for the other three samples varied between 73 to 92%. The AR leach was also performed on 1-g samples and the NaCN leach on 250-g samples. For three of the ore samples, decreasing sample size from 20 g to 1 g did not cause a significant difference in the variance of the Au results. Increasing the sample size from 20 g to 250 g significantly improves the representativity of only the Pahtavaara sample. For the Kutemaja¨rvi, Pahtavaara and Jokisivu ores, a sample larger than 250 g is needed in order to obtain a precision equivalent to that for reference samples.

Том 20, Выпуск 7
Автор(ы):Druguet E., Hutton D.H.W.
Издание:Pergamon, 1998 г., 12 стр.
Язык(и)Английский
Syntectonic anatexis and magmatism in a mid-crustal transpressional shear zone: an example from the Hercynian rocks of the eastern Pyrenees

Hercynian metamorphism and magmatism in the Cap de Creus peninsula (eastern Pyrenees) occurred contemporaneously with non-coaxial deformation in a transpressive regime. An example of this has been taken from a migmatite complex in the northern coast. The studied area is formed by partially melted sil-limanite schists together with two different suites of igneous rocks: a calc-alkaline magmatic sequence, consisting of small granitoid bodies, and later peraluminous leucogranites and pegmatites. All these rocks occur within a NE-SW- to E-W-trending sub-vertical high-strain zone, where a first schistosity is tightly folded and transposed. The relations between folds and crenulation cleavage in the metasediments and deformational fabrics in the granitoids and migmatites provide good evidence for the penecontemporaneity of deformational processes, magmatism and migmatization. Furthermore, the analysis of cross-cutting relationships between different granitoids as well as the observation of their different degrees of deformation verifies that magmatism in this area took place as synkinematic consecutive intrusions from the more basic magmas to the peraluminous acid dykes.

Выпуск 261
Автор(ы):Mercier J.-C.C., Ross.J.V., Xu Y.
Издание:Journal Tectonophysics, 1996 г., 15 стр.
Язык(и)Английский
Diffusion creep in the upper mantle an example from the Tanlu Fault, northeastern China

Ultramafic xenoliths in Neogene alkalic basalts emplaced within the Yitong graben associated with the Tanlu Fault, northeastern China, are mostly variably deformed lherzolites, werhlites and minor pyroxenites. Glass, rich in Si02, A1203, K20 and Na20, is optically recognised as occurring in veins, triple-point grain junctions, and patches in werhlite and some lherzolite samples. Textural observations also suggest that the glass (melt) was involved in the deformation, and was present prior to sampling by the host basalt. Electron microprobe scans for these glass elements indicate that glass is not only present at triple-point grain junctions and in veins, but also completely along some planar grain boundaries.

Выпуск 168
Автор(ы):He Y., Sun M., Xia X., Zhao G.
Издание:Precambrian research, 2009 г., 10 стр.
Язык(и)Английский
SHRIMP and LA-ICP-MS zircon geochronology of the Xiong’er volcanic rocks Implications for the Paleo-Mesoproterozoic evolution of the southern margin of the North China Craton

The Paleo-Mesoproterozoic Xiong’er volcanic rocks along the southern margin of the North China Craton are lithologically and geochemically similar to those formed in subduction-related, continental margin volcanic arcs. The volcanic rocks are primarily composed of basaltic andesites and andesites, with minor dacites and dacitic rhyolites. Traditionally, the Xiong’er volcanic rocks have been divided from lower to upper into the Xushan, Jidanping and Majiahe Formations, but the ages of volcanic rocks in these formations have not been well constrained, which has hindered further understanding the tectonic significance oftheXiong’er volcanicbeltatthe southern marginofthe NorthChina Craton.

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