A TIME-TERM ANALYSIS OF THE FIRST ARRIVAL DATA FROM THE SEISMIC EXPERIMENT IN HUDSON BAY, 1965

1967 ◽  
Vol 4 (5) ◽  
pp. 901-928 ◽  
Author(s):  
Alan Ruffman ◽  
M. J. Keen
Keyword(s):  
Wave Velocity ◽  
Three Dimensional ◽  
Compressional Wave ◽  
Hudson Bay ◽  
Compressional Wave Velocity ◽  
Seismic Experiment ◽  
First Arrival ◽  
Time Term ◽  
Mohorovičić Discontinuity ◽  
Term Analysis

A time-term analysis is made of the first arrival data from the 41 shots of the1965 Hudson Bay seismic experiment. An investigation of the water-wave data is made to determine which of three possible series of navigation is most consistent. A single-layered crust with a compressional wave velocity of 6.33 km/s and an upper mantle compressional wave velocity of 8.27 km/s are proposed for Hudson Bay. The Mohorovičić discontinuity is found to have considerable topography with depths ranging from 42.7 km to less than 26 km. The Churchill–Superior boundary is proposed to be a three-dimensional crustal feature and is extended offshore from Cape Smith and extended westward to the north of the Ottawa Islands through approximately 59° 40′ N and 82° 00′ W. The Mohorovičić discontinuity rises to depths of about 26 km beneath Chesterfield Inlet and Baker Lake. The mantle is about 40 km deep at Churchill, Manitoba and rises to about30 km some 130 km west of Gilmour Island, then drops to almost 42 km farther east. The sudden drop is related to the Churchill–Superior boundary.

scholarly journals Thermophysical and Mechanical Properties of Granite and Its Effects on Borehole Stability in High Temperature and Three-Dimensional Stress

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Wang Yu ◽  
Liu Bao-lin ◽  
Zhu Hai-yan ◽  
Yan Chuan-liang ◽  
Li Zhi-jun ◽  
...  
Keyword(s):  
Elastic Modulus ◽  
High Temperature ◽  
Wave Velocity ◽  
Poisson Ratio ◽  
Three Dimensional ◽  
Good Method ◽  
Compressional Wave ◽  
Compressional Wave Velocity ◽  
Borehole Stability ◽  
Collapse Pressure

When exploiting the deep resources, the surrounding rock readily undergoes the hole shrinkage, borehole collapse, and loss of circulation under high temperature and high pressure. A series of experiments were conducted to discuss the compressional wave velocity, triaxial strength, and permeability of granite cored from 3500 meters borehole under high temperature and three-dimensional stress. In light of the coupling of temperature, fluid, and stress, we get the thermo-fluid-solid model and governing equation. ANSYS-APDL was also used to stimulate the temperature influence on elastic modulus, Poisson ratio, uniaxial compressive strength, and permeability. In light of the results, we establish a temperature-fluid-stress model to illustrate the granite’s stability. The compressional wave velocity and elastic modulus, decrease as the temperature rises, while poisson ratio and permeability of granite increase. The threshold pressure and temperature are 15 MPa and 200°C, respectively. The temperature affects the fracture pressure more than the collapse pressure, but both parameters rise with the increase of temperature. The coupling of thermo-fluid-solid, greatly impacting the borehole stability, proves to be a good method to analyze similar problems of other formations.

THE CRUST OF THE EARTH UNDER HUDSON BAY

1967 ◽  
Vol 4 (5) ◽  
pp. 949-960 ◽  
Author(s):  
J. A. Hunter ◽  
R. F. Mereu
Keyword(s):  
Crustal Thickening ◽  
Hudson Bay ◽  
Near Surface ◽  
Crustal Velocity ◽  
Surface Data ◽  
First Arrival ◽  
Minimum Depth ◽  
Time Term ◽  
Surface Geology ◽  
Mohorovičić Discontinuity

The Hudson Bay crustal experiment of 1965 involved 41 shots placed on two lines, E–W and NW–SE, in the Bay. The first arrival data of eight land stations situated around the bay were utilized in the time–term analysis. The preferred crustal velocity was found to be 6.32 ± .06 km/s, and the velocity of the upper mantle to be 8.23 ± .03 km/s. Depth calculations from time–terms and employing Geological Survey of Canada near-surface data, show the Mohorovicic discontinuity to be undulatory in nature throughout the bay. An overall rise of this interface occurs from a depth at Churchill of approximately 41 km to a minimum depth of approximately 27 km towards Gilmour Island. Crustal thickening occurs again on the east side of the bay, with a depth of 41 km at Povungnituk. As well, the crust thins towards the NW from an approximate depth of 37 km in the center to a depth of 26 km near Chesterfield Inlet. The correlation between existing surface geology and the Mohorovicic discontinuity undulations is discussed.

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