scholarly journals A geophysical study of the North Scappoose Creek, Alder Creek, Clatskanie River lineament, along the trend of the Portland Hills fault, Columbia County, Oregon

2000 ◽  
Author(s):  
Nina Haas
Keyword(s):  
The North ◽  
Geophysical Study ◽  
Columbia County

Geophysical study of basement fractures on the western European and eastern Canadian shelves: transatlantic correlations, and late Hercynian movements

1978 ◽  
Vol 15 (3) ◽  
pp. 397-404 ◽  
Author(s):  
J. P. Lefort ◽  
R. T. Haworth
Keyword(s):  
New England ◽  
Late Carboniferous ◽  
Late Paleozoic ◽  
Stress System ◽  
Northern Spain ◽  
Geological Interpretation ◽  
The Third ◽  
The North ◽  
Geophysical Study ◽  
Western European

Geological interpretation of geophysical data (magnetic, gravimetric and seismic) on the western European and eastern Canadian shelves indicates a transatlantic correlation between the major late Paleozoic fractures of those areas.East–west megafractures, which are primarily grouped in two latitudinal belts at 44° N and 48° N, are the most obvious and correlative. The first zone of fractures was an extension of the South Armorican shear zone, which continued to the north of Flemish Cap. The second was an eastwards extension of the Cobequid–Chedabucto–Scatarie Fault, which crossed Galicia Bank, northern Spain and southern France. A third zone possibly existed between the Clinton–Newbury Fault of New England and mid-Spain, Corsica and Sardinia (when they are moved back to their late Paleozoic positions). The location of the shortening trajectories shows that the first two zones (and perhaps the third one) belonged to the same stress system during late Carboniferous. As a hypothesis, different rates of displacement between 'peri-Atlantic' plates during their northward movement in Late Carboniferous time could be the source of the stress.

GEOPHYSICAL STUDY OF SUBSURFACE STRUCTURE IN SOUTHERN OWENS VALLEY, CALIFORNIA

Geophysics ◽  
1961 ◽  
Vol 26 (1) ◽  
pp. 12-26 ◽  
Author(s):  
M. F. Kane ◽  
L. C. Pakiser
Keyword(s):  
Narrow Channel ◽  
Main Direction ◽  
Subsurface Structure ◽  
Owens Valley ◽  
Deep Subsurface ◽  
Owens Lake ◽  
The North ◽  
Geophysical Study ◽  
North Edge ◽  
Seismic Measurements

Gravity and seismic measurements in southern Owens Valley, California, have outlined a deep subsurface trough, bounded throughout the greater part of its length by steep faults. Depths to the bedrock floor along the central part of the valley range from 3,000 to 9,000 ft below the surface. The subsurface trough is divided into two parts, a narrow channel‐like depression near Lone Pine bounded by northwest‐trending faults, and a broad basin at Owens Lake bounded by a more complex series of border faults. The bedrock ridge that crops out to form Alabama Hills is shown to extend from Independence to the north edge of Owens Lake, nearly twice its visible extent. The main direction of faults that have formed the valley is northwest; subsidiary faults trend north, northeast, and east. A fairly sharp velocity boundary within the Cenozoic valley deposits suggests a change in the rate and character of deposition which was probably the result of renewed uplift in the nearby mountains.

New constraints on the geometry of the Lac Bouchette gabbro – anorthosite from magnetotellurics and magnetics

1995 ◽  
Vol 32 (9) ◽  
pp. 1365-1377 ◽  
Author(s):  
R. L. Kellett
Keyword(s):  
High Frequency ◽  
Seismic Reflection ◽  
Fault Zones ◽  
The South ◽  
Grenville Province ◽  
Magnetotelluric Soundings ◽  
The North ◽  
Geophysical Study ◽  
Magnetic Modelling ◽  
Tectonic Boundaries

A cross section of the resistivity structure through the Lac Bouchette gabbro–anorthosite provides a new image of the thin-skinned geometry of an allochthonous terrane in the western Grenville Province of Canada. Two-dimensional inversion of high-frequency magnetotelluric soundings and magnetic modelling indicate that the gabbro–anorthosite is a 1.5 km thick slice bounded by conductive thrust faults. Graphite, which is present at the margins of the gabbro–anorthosite and in the metasedimentary Réservoir Cabonga terrane to the south, is the most likely source of the enhanced electrical conductivity in the fault zones. The southern margin of the gabbro–anorthosite dips at about 15° to the south beneath the Réservoir Cabonga terrane. The gabbro–anorthosite can be divided into a highly magnetic gabbroic body in the south, a less magnetic metagabbro in the north, and a thin anorthositic lense in the centre. The combination of closely spaced magnetotelluric soundings and magnetic modelling provides independent constraints for gravity and seismic reflection studies in progress. The geometry of the Lac Bouchette gabbro–anorthosite, revealed by this geophysical study, supports a hypothesis that some gabbro–anorthosites behave as competent blocks adjacent to the major tectonic boundaries of the Grenville Province.

scholarly journals Application de la géophysique (méthode géoélectrique) à la reconnaissance du plateau de Meknès (Bassin de Saïss), Maroc [Application of geophysical prospecting (geoelectrical method) for the hydrogeological reconnaissance of the Meknes Plateau (Saiss basin), Morocco]

2001 ◽  
Vol 3 (1-2) ◽  
pp. 35-53
Author(s):  
Ali ESSAHLAOUI ◽  
Hassane SAHBI ◽  
Nacer EL YAMINE
Keyword(s):  
Global Structure ◽  
Mountain Range ◽  
Quantitative Interpretation ◽  
Geophysical Prospecting ◽  
The South ◽  
Borehole Data ◽  
The North ◽  
Geophysical Study ◽  
Electrical Soundings ◽  
Middle Atlas

A geophysical study by the geoelectrical method using electrical soundings, has been carried out in the south-western and southern parts of the Meknes plateau which belongs to the Saïss basin located between the Rif mountain range to the North and the Middle Atlas range to the South. Two significant aquifers are found in the Meknes Plateau: the first one is located in the shallow Plio-Quaternary formations while the second one is inside the deep carbonate beds of the Lias. The quantitative interpretation of electrical soundings from both surface and borehole data resulted in isoresistivity, isopach and longitudinal isoconductance maps that have both a quantitative and a qualitative interest for a better understanding of the global structure of the hydrogeological basin of Saiss.

Investor-State Dispute Settlement under NAFTA Chapter 11: The Shape of Things to Come?

1998 ◽  
Vol 35 ◽  
pp. 263-290
Author(s):  
J. Anthony VanDuzer
Keyword(s):  
Free Trade Agreement ◽  
Dispute Settlement ◽  
Trade Agreement ◽  
Minimum Standards ◽  
The North ◽  
State Behaviour ◽  
Nafta Chapter 11 ◽  
To Come ◽  
The Right

SummaryRecently, there has been a proliferation of international agreements imposing minimum standards on states in respect of their treatment of foreign investors and allowing investors to initiate dispute settlement proceedings where a state violates these standards. Of greatest significance to Canada is Chapter 11 of the North American Free Trade Agreement, which provides both standards for state behaviour and the right to initiate binding arbitration. Since 1996, four cases have been brought under Chapter 11. This note describes the Chapter 11 process and suggests some of the issues that may arise as it is increasingly resorted to by investors.

Long-term Cyclic Variations of Prominences, Green and Red Coronae over Solar Cycles

2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský
Keyword(s):  
Emission Lines ◽  
High Latitudes ◽  
Green Line ◽  
Solar Cycles ◽  
The South ◽  
Coronal Emission ◽  
Local Maxima ◽  
The North ◽  
Cyclic Variations

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.

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