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It is shown that post-island-arc intrusive magmatism of the West-Magnitogorsk Zone embraced the time from Late Devonian to Late Carbon. The new systematization scheme for all variety of intrusive formations is proposed based on the new geological-geochemical data and evolutionary-genetic reconstructions. It presents four discrete intrusive series: 1) gabbro-norite-diorite, 2) gabbro-diorite-granite, 3) peridotite-gabbro-diorite-granite, 4) lamprophyre-dolerite. Each series is characterized by original properties of the body’s morphology and rocks petrography, mineralogy and geochemistry.
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Изложены результаты предварительной оценки базальтов ходжирбулакской свиты гор Сурхантау в качестве базальтового волокна. По данным петрографическо-го исследования породы представлены базальтами миндалекаменной структуры. По содержанию стекловой массы и миндалин кальцита выделены три группы базальтов. Установлена обратная связь между содержаниями основной массы и содержанием кальцита: чем больше основной массы вулканитов, тем меньше кальцита, и наоборот. Модуль кислотности составляет в среднем 3,52.
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Приведены результаты сравнительных минералого-геохимических исследований материала пеплов вулканов Ключевского и Камбального, практически одновременно извергавшихся на Камчатке в марте–апреле 2017 г. Определены химический, фазовый, нормативно-минеральный и микроэлементный составы вещества. Проанализирован состав водных вытяжек из пеплов. По комплексу данных сделан вывод о том, что в обоих случаях пеплы в значительной степени имеют изначальное расплавное происхождение и обнаруживают 75 %-ное сродство с недифференцированным в коровых условиях, т. е. глубинным по источнику, магматогенным веществом. В пеплах Ключевского вулкана обнаружены нитевидные формы и частицы конденсированного абиогенного органополимерного вещества СNОсостава. В пеплах Камбального вулкана, вероятно, имеется примесь резургентного материала из древней постройки кратера, а также минералов гидротермального происхождения. Предложен вероятный сценарий образования преимущественно плагиоклазовых по минеральному составу вулканических пеплов.
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Приведены библиография и краткие аннотации монографий, учебных пособий и тематических сборников статей сотрудников геологического факультета Пермского госуниверситета за 2016 г.
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Впервые в продуктах современного вулканизма на Камчатке обнаружены частицы органических полимеров, вероятно, абиогенного происхождения, что дает возможность трактовать результаты проведенных исследований с позиции вулкано-атмосферно-океанической гипотезы зарождения жизни на Земле, по А.И. Опарину–Дж. Холдейну.
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A physical model of gas discharges, which are one of the four physical processes leading to the formation of heavy elements, is proposed. The possibility of synthesis of heavy elements in laboratory conditions is shown. The results of the study suggest that in the early stages of the evolution of the Universe, the cause of the formation of heavy elements from the hydrogen-helium medium is gas discharges-lightning.
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This paper is an edited version of a submission made to the Lower Hutt City Council Town Planning Hearings Committee in August 1986. The submission was made in support of an objection by the Lower Hutt City Council to a proposed ordinance which prohibited building adjacent to the section of the Wellington fault in Lower Hutt City.
The inadequacies of the proposed ordinance are examined and the issues analysed with particular reference to the protection of life and property, and the risks involved.
Earthquake risks are further analysed and the risk of damage due to shaking compared with those due to fault movement. Comparisons of earthquake risk with other risks accepted by the community are made.
The conclusion drawn is that the additional risk of earthquake damage in a potential fault zone is sufficient to warrant constraints to development, but not so large, in the context of overall risks, to justify prohibition of all development in a fault zone.
Comment and recommendation is made as to appropriate constraints to building development in such zones.
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On March 2 1987, at 01h 42m 34s UT an earthquake of magnitude (ML) 6.3 occurred near 37.91°S, 176.79°E close to the town of Edgecumbe in the North Island, New Zealand. The depth is provisionally estimated to be 12 ± 1 km. Seismic activity in the general area during the previous week culminated in a foreshock on March 2 of ML 5.2 at 01h 35m 37s. Four aftershocks with magnitudes in excess of 5.0 occurred on March 2 at 01h 51m 08s (ML 5.6), 02h 07m 23s (ML 5.1), 06h 56m 32s (ML 5.2) and 07h 55m 09s (ML 5.2).
The earthquakes occurred at the end of summer after a long period of dry weather.
Modified Mercalli Intensities of MM IX have been reported in and around Edgecumbe, with possible instances of MM X. Strong motion accelerographs recorded peak ground acceleration of up to 0.33 g within 15 km of the epicentre. The main shock produced a complex series of surface scarps, the longest being about 7 km long striking SW from Edgecumbe. About 1.3 m maximum extension occurred across the scarp with the area to the north-west being downthrown by about a maximum of 1.5 m which continued to subside slowly. Other smaller normal fault traces have also been detected as well as compressional rolls.
There was extensive evidence of level ground liquefaction and lateral spreading near rivers. Both these phenomena produced eruption of sands at the ground surface. Some wells were observed to have increased flows or increased pressures whilst others were had decreased flows.
General regional subsidence of the alluvial plains in the area up to 2m has been confirmed by levelling completed within three weeks of the earthquake.
Structural damage was confined to the alluvial plains in which the town of Edgecumbe is centred. The depth of sediments on the plains is not less than 350 m.
There was extensive minor damage to roads. Severe damage to many houses and other single storey structures. A dairy factory complex in Edgecumbe, two paper mills in Kawerau and a paperboard mill in Whakatane all sustained damage, in some cases considerable. At present information on the damage in the paper mills is not available.
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This paper was presented as a keynote address at the Pacific Conference on Earthquake Engineering, Wairakei, 5-8 August 1987.
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Although liquefaction of soils during earthquakes has been researched intensively for more than 20 years, it has remained a confusing problem - owing to seemingly divergent viewpoints as to the fundamental nature of the problem. During the past several years there has been a clarifying and coming together of these viewpoints, and hence a much clearer framework of understanding has been established. This new perspective is presented and related to previously developed methods of investigation and analysis, and remaining problems are identified and discussed. Several recent advances re parts of the problems - prediction of limited permanent deformations and delayed failure - are also summarized.
