摘要:

A gravity survey has been carried out in the dolerite area of eastern Ångermanland, central Sweden. A Bouguer map, covering the regions N and NE of Örnsköldsvik, has been prepared. The dolerite can be traced as a large body between and beneath outcrops of dolerite, suggesting a roughly circular shape for the intrustion. However, only a semi-circle can be confirmed, because the dolerite body borders the Bothnian Sea. Gravity profiles across outcropping dolerite sheets have been measured in other parts of the area not included in the Bouguer map. From these, it was found that the dip of the dolerite contacts is parallel to the igneous layering present in the dolerite

ISSN:0016-786X    

DOI:10.1080/11035897909452548

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A geochemical study of the low-grade Seve amphibolites from Mt. Sylarna indicates that they have an affinity to abyssal, tholeiitic magma. The spilitic character of the amphibolites is emphasized in the interpretation of their magma-tectonic implications. A proposed pre-orogenic relationship between, the underlying Särv tholeiitic dykes and the Seve amphibolites in the Sylarna-Helags area is discussed. It is concluded that a magma-genetic relation may exist, which, however, does not place constraints on the translation distance of the Seve Nappe. A hypothetical model for a comagmatic origin of the Särv dolerites and the Mt. Sylarna amphibolites is proposed, involving early basaltic volcanism in the Iapetus Ocean.

ISSN:0016-786X    

DOI:10.1080/11035897909452549

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

ISSN:0016-786X    

DOI:10.1080/11035897909452550

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Recent foundation and rock-excavation works have shown that the gneiss bedrock in the harbour area of Karlshamn is clay-weathered. Swelling clay minerals form part of the weathering products and this has created a number of practical problems, the choice of a suitable foundation pressure to avoid heaving being the most important one. This requires the prediction of a reasonably safe value of the swelling pressure and it is shown that the Yong & Warkentin theory can be used for this purpose, provided that the density of the clay mass is fairly moderate and that the particle orientation is taken into consideration.

ISSN:0016-786X    

DOI:10.1080/11035897909452551

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

ISSN:0016-786X    

DOI:10.1080/11035897909452552

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The Wenlockian Högklint Beds of Gotland represent a “barrier zone” of large bioherms and intervening channels. Three bioherms sampled north of Visby consist of 53% calcilutite matrix and represent quiet-water mud-mounds with organism stabilization but no skeletal framework or properties of wave resistance. The dominant organisms are stromatoporoids (35%), crinoids (18%), tabulate corals (15%) and calcareous algae (13%). Large colonies are less than 0.5 m in size, have relatively simple, massive growth forms and provide few special habitats for other organisms. In consequence, the bioherm-dwelling fauna consists of unspecialized mud-dwellers with the same diversity and taxonomic composition as co-eval, level-bottom communities. No ecologic succession is apparent within bioherms, and an upward change from stromatoporoid to algal dominance reflects a simple change in physical conditions.

ISSN:0016-786X    

DOI:10.1080/11035897909452553

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

On the basis of stratigraphical and diatom-analytical investigations of a series of lakes, the highest shore-line on the Hunneberg hill was determined at around, probably slightly above, 133–134 m above sea-level. From several14C datings of the oldest sediments in the lakes, it appears that the Hunneberg area was already deglaciated in the Bølling Chronozone.

ISSN:0016-786X    

DOI:10.1080/11035897909452554

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Modern land-use planners have to deal with a flood of information, for example special thematic maps, which leads to congestion and complicates the planning procedures. Even an adept planner who may have to resolve conflicts may find that coping with the flood is beyond his capacity. For this reason, the contributions from the geosciences have to be clear-cut, the language of explanation must be easily understandable, and the map arrangements should be clear and precise. The Geoscientific Map of the Natural Environment's Potential (GMNEP) was prepared and published by the Geological Survey in Hannover, Federal Republic of Germany, and adapted by the IUGS Map Commission for that purpose. It consists of a basal set of maps, such as geological, soil and ground-water maps, surficial- and subsurface-resources maps and geological-engineering maps. In a second step, these maps are translated into land-use claim maps, indicating the specific possibilities of land use. When such claim maps are placed one over the other, areas of conflict become apparent between the various interests involved in the utilization of the environmental potential. As a final step in making preparations for planning, a GMNEP Utilization Map (GMNEPU) is prepared from these conflict maps. This final map is the contribution of the geoscientists to planning - an interpretation of the facts at their command in a form more comprehensible to the planner than ever before.

ISSN:0016-786X    

DOI:10.1080/11035897909452555

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

ISSN:0016-786X    

DOI:10.1080/11035897909452556

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The problem of a basement of the supracrustal Åmål group in the Precambrian of south-western Sweden is considered on the basis of the evidence available in the shape of primary, depositional contacts and conglomerate pebbles. The identified pre-Åmål rocks mostly comprise coarse, unmigmatized augen-plutonics, which also occur as inclusions in granodioritic rocks of the provisional Åmål-I group.

ISSN:0016-786X    

DOI:10.1080/11035897909452557

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor