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.

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.

В статье изложены результаты проведенного автором изучения кимериджских отложений Подмосковного края, до последнего времени принадлежавших к наименее известным мезозойским осадкам этой территории. Указывается распространение нижне- и верхнекимериджских отложений, отмечаются их фациальные особенности, дается фаунистическая и литологическая характеристики. Описывается новая для Подмосковного края, вообще редкая порода — спонголит.

The Romanche transverse ridge (equatorial Atlantic) is located in the northern flank of the fracture zone, opposite the eastern ridge-transform intersection (RTI). It constitutes a major positive topographic anomaly that reaches a height of over 4 km above the level predicted by the thermal subsidence curve. A series of E-W aligned peaks, located on the crest of the transverse ridge, were at sea level during early and middle Miocene times; they are presently capped by a ~300 m thick, shallow-water carbonate platform that grew on a subsiding oceanic crust basement surface flattened by erosion at sea level. These structures are now about 1 km below sea level. High resolution seismic reflection surveys and multibeam morphobathymetry as well as study of samples recovered from the carbonate platform allowed a reconstruction of the paleoenvironment and of the vertical movements of the peaks starting from the lower Miocene. Ages derived from microfossils suggest that the base of the carbonate platform dates from 17-25 m.y. ago and the sinking of the platform started between 18 and 13 m.y. ago. These data were included in a numerical simulation model that takes into account thermal and tectonic subsidence, growth potential of the carbonates, subaerial and submarine erosion rates and Mio-Pliocene absolute sea level fluctuations. The results outline the subsidence history of the Romanche transverse ridge and suggest post-Miocene subsidence faster than that predicted by the thermal cooling model.

We report the results of permeability measurements of fault gouge and tonalitic cataclasite from the fault zone of the Median Tectonic Line, Ohshika, central Japan, carried out during triaxial compression tests. The experiments revealed marked effects of deformation on the permeability of the specimens. Permeability of fault gouge decreases rapidly by about two orders of magnitude during initial loading and continues to decrease slowly during further inelastic deformation. The drop in permeability during initial loading is much smaller for cataclasite than for gouge, followed by abrupt increase upon failure, and the overall change in permeability correlates well with change in volumetric strain, i.e., initial, nearly elastic contraction followed by dilatancy upon the initiation of inelastic deformation towards specimen failure. If cemented cataclasite suffers deformation prior to or during an earthquake, a cataclasite zone may change into a conduit for fluid flow. Fault gouge zones, however, are unlikely to switch to very permeable zones upon the initiation of fault slip. Thus, overall permeability structure of a fault may change abruptly prior to or during earthquakes and during the interseismic period. Fault gouge and cataclasite have internal angles of friction of about 36j and 45j, respectively, as is typical for brittle rocks.

On the occasion of the III Colloquium on the Cretaceous of Spain, which took place in More-lla on the 6th, 7th and 8th September 1991 sponsored by the Spanish Group of Mesozoic, there were two field trips to illústrate the present knowledge of the Lower Cretaceous of Northeastern Iberia. These excursions are the object of the present guide-book. In the period passed between when this guide-book was written and its final publication, new results were published which represent a significant increase in our previous knowledge. These publications in international journals, which are referenced at the end of the foreword, together with the figure captions of this guide-book, which have been translated in English, will help the English reader to obtain the information necessary to understand the Lower Cretaceous of Northeastern Iberia.

Геологи всегда мечтали увидеть, что же находится в недрах Земли. Ведь самая глубокая скважина в мире на Кольском полуострове проникла в толщу горных пород всего лишь на 12 км 262 м. Тем не менее о внутреннем строении земного шара мы знаем очень много, и эти знания основаны главным образом на изучении скоростей прохождения упругих волн в недрах Земли. Значения скоростей различных сейсмических волн позволяют рассчитать распределение плотности вещества и давления внутри Земли. Все это дало возможность геофизикам предложить несколько моделей внутреннего строения Земли с выделением в ее пределах ряда сферических оболочек, характеризующихся более или менее однородными физическими свойствами и достаточно четкими поверхностями или границами разделов, обозначенными благодаря изменению скоростей упругих объемных сейсмических волн. Наибольшим признанием ученых до последнего времени пользовалась модель строения Земли К.Е. Буллена, созданная в 1959–1969 годах. В последнее время используется более новая, уточненная модель PREM (Prelimenary Reference Earth Model), которая характеризуется “нормальным”, то есть усредненным распределением с глубиной различных физических параметров, в том числе скоростей сейсмических волн. Наиболее важным источником информации о строении Земли являются землетрясения, самые глубокие очаги которых располагаются на уровне примерно 700 км. Все землетрясения порождают сейсмические волны деформации, пронизывающие в различных направлениях земной шар.

Книга состоит из двух частей. Первая часть посвящена выявлению основных закономерностей распространения, особенностям строения и условиям и источникам накопления соленосных толщ, а также аккумуляции в них органического вещества. В этой части приводятся данные о распространении соленосных толщ во всех соляных бассейнах мира и о количестве содержащейся в них соли. Показано, что соль распределена неравномерно по системам фанерозоя.