Rb–Sr biotite and whole-rock data from the Kapuskasing uplift and their bearing on the cooling and exhumation history

1994 ◽  
Vol 31 (7) ◽  
pp. 1172-1181 ◽  
Author(s):  
J. A. Percival ◽  
Z. E. Peterman
Keyword(s):  
Fault Zone ◽  
Spatial Relationship ◽  
Paleomagnetic Data ◽  
Isotopic Ratios ◽  
The West ◽  
Rapid Cooling ◽  
Early Proterozoic ◽  
Granitoid Rocks ◽  
Relationship Of ◽  
Exhumation History

Rb–Sr isotopic ratios were measured on biotite and whole rocks from a suite of 21 granitoid rocks from the southern Kapuskasing uplift. Results of 18 of the whole-rock analyses fall on an isochron with an age of 2.677 ± 0.057 Ga and Sri = 0.70080. Biotite model ages range from 2.50 to 1.93 Ga in a general spatial relationship of decreasing age with depth in the structural section as calibrated with the igneous hornblende barometer for tonalitic rocks and garnet–pyroxene barometers for granulites. Near the Michipicoten belt in the west, biotite ages of ~ 2 Ga reflect disturbances also recorded by paleomagnetic and whole-rock Rb–Sr systems. To the east, in a 70 km long northwest–southeast transect toward the Ivanhoe Lake fault zone, ages decrease from 2.50 to 1.95 Ga. In a southern transect ages are in the range 2.30–2.38 Ga to within 15 km of the fault, reflecting consistent erosion levels corresponding to ~ 0.53 MPa, but decrease to 1.93 Ga to the east, in concert with paleopressures in the 0.7–1.0 GPa range.A plateau of low Rb–Sr biotite dates is not evident, suggesting that the Kapuskasing uplift event exposed a frozen-in cooling profile, rather than setting the Rb–Sr clock by rapid cooling of the rocks from above their closure temperature. The youngest biotite date of 1.93 Ga therefore provides a maximum age for uplift, consistent with paleomagnetic data from Archean rocks and Early Proterozoic dykes, but in conflict with some K–Ar and 40Ar/39Ar biotite age data.

Constraints on the nature of the Kapuskasing structural zone from the study of Proterozoic dyke swarms

1994 ◽  
Vol 31 (7) ◽  
pp. 1182-1196 ◽  
Author(s):  
H. C. Halls ◽  
H. C. Palmer ◽  
M. P. Bates ◽  
Wm. C. Phinney
Keyword(s):  
Magnetic Field ◽  
Fault Zone ◽  
Magnetic Polarity ◽  
High Alumina ◽  
Superior Province ◽  
Structural Studies ◽  
The West ◽  
Early Proterozoic ◽  
Dyke Swarms ◽  
Broad Scale

Petrochemical, paleomagnetic, and structural studies on Early Proterozoic dyke swarms show that the rocks of the Kapuskasing structural zone (KSZ), central Superior Province, were upthrust about 10–15 km along the Ivanhoe Lake fault after intrusion of 2.04 Ga Kapuskasing dykes. This uplift was part of a more widespread deformation in flanking terranes that involved sinistral motion along north–north-northwest-trending faults, dextral displacement along east-northeast–northeast-trending faults, and a distortion of the 2.45 Ga Matachewan swarm to the west and northwest of the Ivanhoe Lake fault. The most spectacular demonstration that the KSZ is largely a product of Proterozoic deformation is that Matachewan dykes change their magnetic polarity on crossing the zone, a consequence of remanence acquisition at deep crustal levels being delayed until after a reversal of the earth's magnetic field and prior to uplift of the dykes.Matachewan and Kapuskasing dykes within the amphibolite- to granulite-grade rocks of the KSZ are relatively fresh and contain a high-alumina green amphibole and feldspar laths that exhibit tea-coloured clouding due to the presence of submicroscopic inclusions of magnetite. These features may be diagnostic of crystallization at deeper crustal levels because they are found in regions where Rb–Sr biotite ages from tonalites suggest broad-scale uplift of the crust after about 2 Ga. About 50 km west of the KSZ, dykes exhibiting clouded feldspar and high-alumina amphiboles occur on the upthrown side of the Budd Lake fault zone, which has a trend similar to that of the Ivanhoe Lake fault. Therefore a second thrust block may exist, raising the possibility that the KSZ represents the basal member of a series of imbricate thrust slices that extends westwards from the Ivanhoe Lake fault. Radiometric age data suggest that the region affected by this Early Proterozoic deformation continues to the northwest for a further 300 km.

Ultrastructural evidence for mast cell-macrophage interrelationships in the dura mater of the rat: Infrequent mast cell-nerve associations

1990 ◽  
Vol 48 (3) ◽  
pp. 352-353
Author(s):  
Ruth V.W. Dimlich
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Dura Mater ◽  
Spatial Relationship ◽  
Potassium Phosphate ◽  
Plasma Extravasation ◽  
Close Spatial Relationship ◽  
Male Wistar Rats ◽  
Headache Pain ◽  
Relationship Of

Mast cells in the dura mater of the rat may play a role in cerebral pathologies including neurogenic inflammation (vasodilation; plasma extravasation) and headache pain . As has been suggested for other tissues, dural mast cells may exhibit a close spatial relationship to nerves. There has been no detailed ultrastructural description of mast cells in this tissue; therefore, the goals of this study were to provide this analysis and to determine the spatial relationship of mast cells to nerves and other components of the dura mater in the rat.Four adult anesthetized male Wistar rats (290-400 g) were fixed by perfusion through the heart with 2% glutaraldehyde and 2.8% paraformaldehyde in a potassium phosphate buffer (pH 7.4) for 30 min. The head of each rat was removed and stored in fixative for a minimum of 24 h at which time the dural coverings were removed and dissected into samples that included the middle meningeal vasculature. Samples were routinely processed and flat embedded in LX 112. Thick (1 um) sections from a minimum of 3 blocks per rat were stained with toluidine blue (0.5% aqueous).

scholarly journals Geo-Spatial Analysis of Population Density and Annual Income to Identify Large-Scale Socio-Demographic Disparities

2021 ◽  
Vol 10 (7) ◽  
pp. 432
Author(s):  
Nicolai Moos ◽  
Carsten Juergens ◽  
Andreas P. Redecker
Keyword(s):  
Population Density ◽  
Large Scale ◽  
Methodological Approach ◽  
Spatial Relationship ◽  
Postal Code ◽  
Annual Income ◽  
Choropleth Maps ◽  
Clustering Approach ◽  
Relationship Of ◽  
Insight Into

This paper describes a methodological approach that is able to analyse socio-demographic and -economic data in large-scale spatial detail. Based on the two variables, population density and annual income, one investigates the spatial relationship of these variables to identify locations of imbalance or disparities assisted by bivariate choropleth maps. The aim is to gain a deeper insight into spatial components of socioeconomic nexuses, such as the relationships between the two variables, especially for high-resolution spatial units. The used methodology is able to assist political decision-making, target group advertising in the field of geo-marketing and for the site searches of new shop locations, as well as further socioeconomic research and urban planning. The developed methodology was tested in a national case study in Germany and is easily transferrable to other countries with comparable datasets. The analysis was carried out utilising data about population density and average annual income linked to spatially referenced polygons of postal codes. These were disaggregated initially via a readapted three-class dasymetric mapping approach and allocated to large-scale city block polygons. Univariate and bivariate choropleth maps generated from the resulting datasets were then used to identify and compare spatial economic disparities for a study area in North Rhine-Westphalia (NRW), Germany. Subsequently, based on these variables, a multivariate clustering approach was conducted for a demonstration area in Dortmund. In the result, it was obvious that the spatially disaggregated data allow more detailed insight into spatial patterns of socioeconomic attributes than the coarser data related to postal code polygons.

scholarly journals The cyst-theca relationship of <i>Protoperidinium americanum</i> (Gran & Braarud) Balech

1987 ◽  
Vol 6 (2) ◽  
pp. 113-121 ◽  
Author(s):  
Jane Lewis ◽  
J. D. Dodge
Keyword(s):  
West Coast ◽  
The West ◽  
Single Cyst ◽  
Relationship Of ◽  
Germination Techniques ◽  
Cyst Germination

Abstract. The cyst-theca relationship of Protoperidinium americanum (Gran &amp; Braarud) Balech was investigated using single cyst germination techniques. This Protoperidinium has an unusual theca with four intercalary plates (plate formula 4’, 4a, 7″, 4c, 7s, 5″’, 2″″). It has a distinctive brown capsulate cyst which has an apical archeopyle. The position of this species in the genus Protoperidinium is discussed. The distribution of the cyst on the west coast of Scotland is described.

Intrasellar Intercarotid Communicating Artery Associated with Agenesis of the Right Internal Carotid Artery: Case Report

Neurosurgery ◽  
1988 ◽  
Vol 23 (6) ◽  
pp. 770-773 ◽  
Author(s):  
Masahiko Udzura ◽  
Hiroo Kobayashi ◽  
Yoshio Taguchi ◽  
Hiroaki Sekino
Keyword(s):  
Magnetic Resonance Imaging ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Internal Carotid ◽  
Spatial Relationship ◽  
Resonance Imaging ◽  
Anomalous Artery ◽  
Magnetic Resonance Imaging Mri ◽  
The Right ◽  
Relationship Of

Abstract A 54-year-old man with a right hemiparesis was found to have an intrasellar intercarotid communicating artery associated with agenesis of the right internal carotid artery. Magnetic resonance imaging (MRI) studies demonstrated the spatial relationship of the anomalous artery to the surrounding structures, thus suggesting an embryonic enlargement of the capsular artery as a source of this anomalous artery.

scholarly journals On the Question of Medieval Artillery in the Muslim Regions of Contemporary Russia

Islamovedenie ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 30-40
Author(s):  
Nabiev Rustam Fanisovich ◽  
Keyword(s):  
Western Europe ◽  
New Technologies ◽  
Northern Eurasia ◽  
Sources Of Information ◽  
Islamic Culture ◽  
The West ◽  
Muslim Countries ◽  
History Of ◽  
The Russian Federation ◽  
Relationship Of

The article deals with the problem of the spread of artillery weapons from the East to the West through the territory of the Eurasian steppes. Among the regions important for the devel-opment of firearms were countries with Islamic culture, which are currently part of the Russian Federation and the CIS. They were one of the most important links in the movement of new technologies from the East to Europe. Evidence of the development of artillery in the northern Muslim countries is not only written sources, but also finds of genuine medieval weapons. The author shows that the Muslim peoples of northern Eurasia have contributed to the world process of the development and spread of firearms. The article substantiates the view that in the territory of Russia powder technologies, the newest at that time, began to be used much earlier than in Western Europe. The author also identifies a number of areas of research into the history of powder technologies in the medieval Muslim world, such as sources of information, regions, landscapes, the main ways of spreading technologies, as well as terminology from the standpoint of cultural relationship of languages

scholarly journals Correlation analysis between multifractal characteristics of regional geomorphology and development of geological disasters

2021 ◽  
Vol 25 (1) ◽  
pp. 49-55
Author(s):  
Yiying Xiong
Keyword(s):  
Correlation Analysis ◽  
Spatial Relationship ◽  
Analysis Method ◽  
Self Similarity ◽  
Geological Disasters ◽  
Geological Disaster ◽  
Correlation Analysis Method ◽  
Fractal Spectrum ◽  
Fractal Characteristics ◽  
Relationship Of

In view of the inaccuracy of the traditional correlation analysis method, this paper proposes a correlation analysis method between the multifractal characteristics of regional landforms and the development of geological disasters. Firstly, the multifractal characteristics of regional landforms are described by using the basic fractal characteristics of self-similarity or scale invariance. Then the corresponding relation table is established according to the width of the fractal spectrum and the number of landslides and hidden dangers, and the spatial relationship of geological disaster development is analyzed. Combined with the above-mentioned spatial relationship of geological disaster development and the multifractal characteristic data of regional landforms, the correlation coefficient between the two is calculated to complete the correlation analysis between the multifractal characteristics of regional geomorphology and the development of geological disasters. The experimental results show that compared with the traditional correlation analysis method, the correlation analysis results of the multifractal characteristics of regional geomorphology and the development of geological disasters are more accurate.

scholarly journals Dinamika Kepentingan dan Interaksi Sosial Pedesaan: Studi Implikasi Alih Fungsi Lahan

2016 ◽  
Vol 3 (2) ◽  
pp. 64
Author(s):  
Dhina Yuliana ◽  
Faris Rahmadian ◽  
Nana Kristiawan ◽  
Selvy Anggriani Syarif
Keyword(s):  
Land Use ◽  
Rural Communities ◽  
Social Interactions ◽  
Social Relations ◽  
Land Use Changes ◽  
Land Conversion ◽  
The West ◽  
The Social ◽  
Relationship Of ◽  
Housing Estates

Land-use changes or land conversion issues not only poses a threat of ecological or environmental, but also trigger a variety of dynamics and complexity of social relations in it. West Cilebut Villages has been the target of investors and developers of housing since the 1990s, and now the West Cilebut Villages has changed from an area full of green “romantic” village, into the region filled with concrete. Therefore, this study was conducted to answer fundamental issues related to the issue of land conversion in the West Cilebut Village, first is to see the map and interests between actors in relation to land conversion in the West Cilebut Village, and second to know the social interactions dynamics that occur in West Cilebut community, following the land conversion from the farm into housing estates. The results showed that there are three main actors in relation to issues of land use change in West Cilebut Village: (1) The Housing Developer; (2) Village Apparatus / Government; (3) Society; where the three actors have a role and importance of different orientations. Meanwhile, social interaction between housing and rural communities basically shows a relationship of mutual need. Construction of housing community that luxurious and exclusive slowly turns into inclusive and reflect a resiprocity of the two communities. 

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