Discussion: Inferred subglacial meltwater origin of lakes on the southern border of the Canadian Shield

1995 ◽  
Vol 32 (5) ◽  
pp. 672-673 ◽  
Author(s):  
I.A. Brookes
Keyword(s):  
Canadian Shield ◽  
Southern Border ◽  
Subglacial Meltwater

Inferred subglacial meltwater origin of lakes on the southern border of the Canadian Shield

1994 ◽  
Vol 31 (11) ◽  
pp. 1630-1637 ◽  
Author(s):  
Robert Gilbert ◽  
John Shaw
Keyword(s):  
Cross Sections ◽  
Land Surface ◽  
Large Scale ◽  
Flow Direction ◽  
Canadian Shield ◽  
Laurentide Ice Sheet ◽  
Southern Border ◽  
Paleozoic Rocks ◽  
Accelerated Flow ◽  
Subglacial Meltwater

Paleozoic rocks form an escarpment up to 35 m high at the border with the Frontenac Axis of the Canadian Shield in southeastern Ontario. The escarpment, which lies nearly transverse to the flow direction of Pleistocene ice and subglacial meltwater in the region, is cut by a series of deep channels locally incised into the bedrock at the escarpment. A subbottom acoustic survey of two of these channels and mapping of a third, partly flooded channel revealed the shape of the bedrock surface beneath the water and glacial and postglacial sediments of lakes now occupying the channels. Most cross sections show a smooth-walled, dominant depression eroded up to 100 m below the land surface nearby, and flanked by one or more secondary depressions. The pattern changes considerably in detail, making secondary depressions especially difficult to trace along the length of the lake. The pattern is similar to that of subglacial fluvial erosion marks more than three orders of magnitude smaller found in bedrock throughout the region. We ascribe the origin of these channels cut across the escarpment to periodic, large flows of water beneath the Laurentide Ice Sheet. The escarpment formed a barrier through which the flow was forced at regular intervals, eroding large-scale channels at these sites of confined and accelerated flow, while the ice was still largely in contact with the surrounding surface. At the highest flows the entire surface was flooded and eroded.

Some Problems of Classification in the Canadian Pre-Cambrian Shield.

1927 ◽  
Vol 64 (1) ◽  
pp. 1-7 ◽  
Author(s):  
M. E. Wilson
Keyword(s):  
Lake Superior ◽  
Field Work ◽  
Canadian Shield ◽  
Geological Survey ◽  
Considerable Difficulty ◽  
North West ◽  
Southern Border ◽  
Positive Correlations ◽  
Vast Area

The region lying along the southern border of the Canadian Shield, the St. Lawrence basin, to which by far the greater part of the field work so far performed in this vast area has been confined, is divided into four geographically separate sub-provinces, in each of which the succession of formations is so different that few positive correlations of either formations or unconformities in different sub-provinces can be made. It is probable, however, that all geologists familiar with this region are agreed that there is a palaeoplain at the base of the Huronian that originally at least extended over the southern part of the Canadian Shield. If the existence of this palaeoplain be assumed as established then there are two major problems in Pre-Cambrian classification in this region that remain unsolved: (1) What is the position of the pre-Huronian palaeoplain in the succession of formations present in the sub-province north-west of Lake Superior and in the Grenville sub-province? and (2) is there a second erosion plain within the pre-Huronian complex, and, if so, can it be used satisfactorily for the classification of the pre-Huronian into two major divisions equivalent in rank to the Huronian?The purpose of this paper has been to point out (1) that there is no present agreement regarding the solution of either of these problems; (2) that the existence of a widespread unconformity within the pre-Huronian complex of the St. Lawrence province is, as yet, only a hypothesis, and (3) that there are only two logical courses to be followed in the classification of the Pre-Cambrian formations of the Canadian Shield, either to adopt the dual classification or to use it tentatively in the manner indicated in the accompanying table, until the existence of the second widespread unconformity is established or disproved. It may be suggested, however, that since considerable difficulty is being encountered in applying the dual classification even within the St. Lawrence province, it may be more practical to adopt the dual classification for the major divisions of the Pre-Cambrian notwithstanding the possible presence of an unconformity within the pre-Huronian complex.In conclusion the writer wishes to express his indebtedness to his colleagues of the Geological Survey of Canada, W. H. Collins, F. J. Alcock, T. L. Tanton, and J. F. Wright, for criticism of the columns in the table of formations having reference to the different sub-provinces with which they are especially familiar.

In search of the camp of the IV Scythian legion near ancient Artaxata: research at Pokr Vedi 2015–2018

2020 ◽  
pp. 409-432
Author(s):  
Oskar Kubrak ◽  
Paulina Kubrak ◽  
Mkrtich H. Zardaryan
Keyword(s):  
Electrical Resistivity ◽  
Aerial Photography ◽  
Magnetic Measurements ◽  
Roman Army ◽  
Field Surveys ◽  
Non Invasive ◽  
Southern Border ◽  
Building Activities ◽  
Geophysical Measurements ◽  
Selection Of

During the last years of Emperor Trajan’s reign, the Legio IV Scythica was stationed in the capital of Armenia at that time, Artaxata. It had made its way there within the scope of the Roman campaign against the Parthians. Its presence was immortalised on stamped rooftiles, bricks and a monumental inscription discovered by the southern border of the present-day village of Pokr Vedi. The inscription carved into limestone confirms the building activities of the Roman army. Similar inscriptions were frequently placed on the gates and most important buildings in legionary camps. Polish and Armenian archaeologists undertook a joint search for the supposed camp of the Fourth Scythian Legion in the vicinity of the present-day village of Pokr Vedi, where the above-mentioned construction inscription had been found. The field surveys conducted within the framework of the Pokr Vedi Project were mainly of a non-invasive character. The following were applied: surface prospection, aerial photography, interviews with the inhabitants, scanning of part of the terrain and geophysical measurements done using two methods: electrical resistivity and magnetic measurements. The accumulated data enabled the selection of sites in which survey trenches were located

Language Maintenanceand The Preservation of Ethnic Identity: A Case of Malay Muslims in Southern Thailand

2012 ◽  
Vol 8 ◽  
pp. 297-308
Author(s):  
Nonglaksana Kama ◽  
Munirah Yamirudeng
Keyword(s):  
Ethnic Identity ◽  
Language Shift ◽  
Muslim Community ◽  
Cultural Groups ◽  
Know How ◽  
Thai Language ◽  
Ethnic Language ◽  
Southern Thailand ◽  
Southern Border ◽  
Vital Element

Language is known to have an effect on ethnic identity.For cultural groups who hold knowledge of ethnic language as a core value, language shift can lead to a loss of ethnic identity, cultural fragmentation and “non-authentic” expressions of ethnicity Thelanguage has played and is still playing a symbolic role in the evolution and maintenance of ethnic identity within the Malay Muslim community in southern Thailand. Itis significant to know how the Malay language was used as a symbol to create and sustain the Malay identity on the ways in which Malay Muslims today understand ethnic identity, and how ethnic language fits into their own ethnic self-identifications.This paper attempts to answer the question why Malay language constitutes a vital element in the maintenance of Malay ethnic identity among the Malays of southern Thailand.Two facts have been identified regarding the language and ethnicity link among Malay Muslims. First, Malay language is seen as a relevant ethno-cultural marker and its usage is limited within family, relatives and close friends. Second, Malay language is preserved along with Thai language, making many Malay Muslims bilingual, which is quite typical in the southern border provinces of Thailand.

Military-Police Fusion at the Southern Border

2020 ◽  
Vol 35 (2) ◽  
pp. 101-121
Author(s):  
Chava Brownfield-Stein
Keyword(s):  
Women Soldiers ◽  
High Tech ◽  
Ground Vehicles ◽  
Operational Environment ◽  
Military Police ◽  
Novel Technologies ◽  
Southern Border ◽  
Key Dimensions ◽  
Israel Defense Forces ◽  
New Phase

Examining the activities of the Israel Defense Forces along the Gaza-Israel border, this article identifies a new phase in what the author calls ‘military-police fusion’. The analysis focuses on novel technologies—remote-controlled weapon stations and unmanned ground vehicles—and on the women soldiers who operate these systems. The central claim is that the blurring of boundaries between military and policing missions, combined with high-tech weaponry, has resulted in the development and implementation of new modes of violence that are currently undergoing a process of redefinition and feminization. The article addresses three key dimensions of the processes occurring in the hybrid operational environment along the Gaza-Israel border: the legal dimension, the technological dimension, and the gender dimension.

The Archaean Atâ intrusive complex (Atâ tonalite), north-east Disko Bugt, West Greenland

1999 ◽  
pp. 103-112
Author(s):  
Feiko Kalsbeek ◽  
Lilian Skjernaa
Keyword(s):  
Intrusive Complex ◽  
The South ◽  
Original Series ◽  
Early Proterozoic ◽  
West Greenland ◽  
North East ◽  
The North ◽  
Southern Border ◽  
Area North ◽  
Igneous Layering

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Kalsbeek, F., & Skjernaa, L. (1999). The Archaean Atâ intrusive complex (Atâ tonalite), north-east Disko Bugt, West Greenland. Geology of Greenland Survey Bulletin, 181, 103-112. https://doi.org/10.34194/ggub.v181.5118 _______________ The 2800 Ma Atâ intrusive complex (elsewhere referred to as ‘Atâ granite’ or ‘Atâ tonalite’), which occupies an area of c. 400 km2 in the area north-east of Disko Bugt, was emplaced into grey migmatitic gneisses and supracrustal rocks. At its southern border the Atâ complex is cut by younger granites. The complex is divided by a belt of supracrustal rocks into a western, mainly tonalitic part, and an eastern part consisting mainly of granodiorite and trondhjemite. The ‘eastern complex’ is a classical pluton. It is little deformed in its central part, displaying well-preserved igneous layering and local orbicular textures. Near its intrusive contact with the overlying supracrustal rocks the rocks become foliated, with foliation parallel to the contact. The Atâ intrusive complex has escaped much of the later Archaean and early Proterozoic deformation and metamorphism that characterises the gneisses to the north and to the south; it belongs to the best-preserved Archaean tonalite-trondhjemite-granodiorite intrusions in Greenland.

THE ASSOCIATION OF SUBGLACIAL MELTWATER ACTIVITY WITH ICE-SHEET RETREAT IN MARGUERITE BAY, ANTARCTICA

2020 ◽  
Author(s):  
Lindsay Prothro ◽  
◽  
John B. Anderson ◽  
Wojciech Majewski ◽  
Yusuke Yokoyama
Keyword(s):  
Ice Sheet ◽  
Marguerite Bay ◽  
Subglacial Meltwater

Clinical and ethical perspective of neurosurgical care in patients from beyond the southern border of Turkey: challenges of patients in war

2021 ◽  
Author(s):  
Pınar Akdemir Özışık ◽  
Kubilay Murat Özdener ◽  
Berkan Ural ◽  
Uygur Er ◽  
Ali Savaş
Keyword(s):  
Ethical Perspective ◽  
Southern Border
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