The Mid-Atlantic Ridge near 45° N. XIII. Magnetic properties of basalt bore-core

1970 ◽  
Vol 7 (6) ◽  
pp. 1515-1527 ◽  
Author(s):  
J. Brooke ◽  
E. Irving ◽  
J. K. Park
Keyword(s):  
Magnetic Properties ◽  
Coercive Force ◽  
Physical Properties ◽  
Remanent Magnetization ◽  
Natural Remanent Magnetization ◽  
The Core ◽  
Mid Atlantic Ridge ◽  
Technical Interest

Three bore-cores containing basalts have been obtained from the Mid-Atlantic Ridge at 45° N. The material is fresh and ideal for the study of physical properties. The drilling record and the nature of the core itself suggest that much of the basalt is from detached boulders, although one core may be in situ. In one core, variations in coercivity by a factor 2 occur within a distance of 5 cm. The coercive force spectra of anhysteretic and natural remanent magnetization are similar, but there are small differences due to secondary components which are used to predict correctly the polarity of 11 out of 12 specimens studied. This result may be of technical interest only since there is no guarantee that the material is in situ.

The Mid-Atlantic ridge near 45° N. VII. Magnetic properties and opaque mineralogy of dredged samples

1970 ◽  
Vol 7 (2) ◽  
pp. 239-256 ◽  
Author(s):  
C. M. Carmichael
Keyword(s):  
Magnetic Properties ◽  
Remanent Magnetization ◽  
Complex Structure ◽  
Magnetic Anomalies ◽  
Natural Remanent Magnetization ◽  
Coarse Grained ◽  
X Ray Diffraction ◽  
Field Polarity ◽  
Fine Grained ◽  
Mid Atlantic Ridge

Measurements of the magnetic properties, paleomagnetic field intensity, and the inferred paleomagnetic field polarity have been made using fine grained basalt and coarser grained rock samples dredged from the mid-Atlantic ridge near 45° N and supplied by the Geological Survey of Canada. The opaque mineralogy of the samples was studied by microscope, Curie point, and X-ray diffraction techniques. The natural remanent magnetization of the basalt is of the order of 5 to 10 × 10−3 e.m.u./cm3 with some values from the center of the median valley reaching 10−1 e.m.u./cm3. Magnetic anomalies over the ridge can be accounted for by the remanent magnetization of a few hundred meters of this basalt. The coarse grained rocks were relatively weakly magnetized, and while they contribute little to the magnetic anomalies, their diverse character suggests that the major portion of the oceanic crust, below a thin veneer of fine grained basalt, has differentiated into a complex structure.

Magnetic and Electrical Properties of TPU/NR Blends Filled NiZn Ferrite

2015 ◽  
Vol 754-755 ◽  
pp. 256-260
Author(s):  
Nor Azwin Ahad ◽  
Sahrim Haji Ahmad ◽  
Jalilah Abd Jalil
Keyword(s):  
Magnetic Properties ◽  
Electrical Properties ◽  
Coercive Force ◽  
Natural Rubber ◽  
Physical Properties ◽  
Saturation Magnetization ◽  
Thermoplastic Polyurethane ◽  
Polymer System ◽  
Filler Loading ◽  
Blending Method

Blending method of two or more polymer is well-established strategy to modify the physical properties without synthesizes the new polymer system. While adding magnetic filler will change the magnetic properties of the polymer as an insulator to the materials that are magnetic. The TPU/NR blends as matrix was prepared from thermoplastic polyurethane (TPU) and natural rubber (NR) in the ratio 85/15 with 1-5 wt% NiZn ferrites. The value of saturation magnetization (Ms), remanance (Mr) increased, while coercive force (Hc) decreases with increasing filler loading. For the electrical properties, resistivity decreased and conductivity increased with the increase of NiZn ferrite loading in the blends.

Magnetic Properties of the Cylindrical Ising Nanowire: A Monte Carlo Simulation Study

SPIN ◽  
2017 ◽  
Vol 07 (04) ◽  
pp. 1750011 ◽  
Author(s):  
A. Jabar ◽  
R. Masrour ◽  
M. Hamedoun ◽  
A. Benyoussef
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Magnetic Properties ◽  
Crystal Field ◽  
Remanent Magnetization ◽  
Hysteresis Loops ◽  
Core Shell ◽  
Monte Carlo Simulation Study ◽  
The Core ◽  
Magnetic Nanowire

A cylindrical ferrimagnetic magnetic nanowire system of core and shell layers has been investigated using Monte Carlo simulation. Critical temperature is obtained for different values of exchange couplings at the core–shell interface, at shell–shell and core–core. The total magnetization has been the determinate for different values of crystal field. Hysteresis loop, coercive field and remanent magnetization of a core and shell layers are obtained using the Monte Carlo simulation. A number of characteristic behaviors are found, such as the occurrence of single and triple hysteresis loops for appropriate values of crystal field, temperatures values and exchange interaction values.

ALNICO-II

Alloy Digest ◽  
1967 ◽  
Vol 16 (11) ◽  
Keyword(s):  
Magnetic Properties ◽  
Coercive Force ◽  
Physical Properties ◽  
Tensile Properties ◽  
Heat Treating ◽  
High Energy ◽  
General Purpose ◽  
Magnetic Alloy ◽  
Magnet Alloy ◽  
Permanent Magnet Alloy

Abstract ALNICO II is a general purpose permanent magnet alloy recommended for applications where better magnetic properties than Alnico I are desired. It is a high coercive force, high energy magnetic alloy. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on heat treating and machining. Filing Code: Fe-31. Producer or source: Allegheny Ludlum Corporation.

COBALT MAGNET STEEL

Alloy Digest ◽  
1956 ◽  
Vol 5 (6) ◽  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Fields ◽  
Coercive Force ◽  
Physical Properties ◽  
Alloy Steel ◽  
Heat Treating ◽  
Strong Magnetic Fields ◽  
Steel Mills

Abstract Cobalt magnet steels have high coercive force which makes it possible to maintain strong magnetic fields with relatively short magnets. These alloys must be hardened by drastic quenching in oil to obtain the maximum magnetic properties. This datasheet provides information on composition, physical properties, and elasticity. It also includes information on forming, heat treating, and machining. Filing Code: SA-44. Producer or source: Alloy steel mills and foundries.

The identification of single-domain titanomagnetite particles by means of transmission electron microscopy

1979 ◽  
Vol 16 (2) ◽  
pp. 375-379 ◽  
Author(s):  
P. P. K. Smith
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Remanent Magnetization ◽  
Magnetic Domain ◽  
Natural Remanent Magnetization ◽  
Small Particles ◽  
Dispersed Particles ◽  
Transmission Electron ◽  
Mid Atlantic Ridge ◽  
Means Of Transmission

A basalt sample dredged from the axis of the Mid-Atlantic Ridge has been ion-thinned and examined by transmission electron microscopy. Finely dispersed particles as small as 0.04 μm in diameter, occurring in amorphous patches of the rock, have been identified as titanomagnetite by means of electron diffraction and microanalysis. These small particles have dimensions appropriate to single magnetic domain behaviour, and are considered to be largely responsible for the strong and very stable natural remanent magnetization of this rock.

scholarly journals A stratigraphy-based method for reconstructing ice core orientation

2021 ◽  
Author(s):  
Julien Westhoff ◽  
Nicolas Stoll ◽  
Steven Franke ◽  
Ilka Weikusat ◽  
Paul Bons ◽  
...  
Keyword(s):  
Physical Properties ◽  
Ice Core ◽  
Ice Cores ◽  
The Core ◽  
Ice Stream ◽  
Orientation Method

<p>Ever since the first deep ice cores were drilled, it has been a challenge to determine their original, in-situ orientation. In general, the orientation of an ice core is lost as the drill is free to rotate during transport to the surface. For shallow ice cores, it is usually possible to match the adjacent core breaks, which preserves the orientation of the ice column. However, this method fails for deep ice cores, such as the EastGRIP ice core in Northeast Greenland. We provide a method to reconstruct ice core orientation using visual stratigraphy and borehole geometry. As the EastGRIP ice core is drilled through the Northeast Greenland Ice Stream, we use information about the directional structures to perform a full geographical re-orientation. We compared the core orientation with logging data from core break matching and the pattern of the stereographic projections of the crystals’c-axis orientations. Both comparisons agree very well with the proposed orientation method. The method works well for 441 out of 451 samples from a depth of 1375–2120 m in the EastGRIP ice core. It can also be applied to other ice cores, providing a better foundation for interpreting physical properties and understanding the flow of ice.</p>

IN‐SITU DETERMINATION OF THE REMANENT MAGNETIC VECTOR OF TWO‐DIMENSIONAL TABULAR BODIES

Geophysics ◽  
1966 ◽  
Vol 31 (5) ◽  
pp. 949-962 ◽  
Author(s):  
H. P. Ross ◽  
P. M. Lavin
Keyword(s):  
Remanent Magnetization ◽  
Natural Remanent Magnetization ◽  
Potential Fields ◽  
Small Samples ◽  
Magnetic Survey ◽  
Two Dimensional ◽  
Magnetic Vector ◽  
Gravity And Magnetic

Recent studies have shown that many rocks of the earth’s crust have a substantial component of remanent magnetization. Extensive sampling is required to determine adequately the remanent vector from small samples. A field technique has been developed (and tested on model data) for the in‐situ determination of the resultant (induced+remanent) magnetic vector of bulk volumes of rock, using a combined analysis of the gravity and magnetic fields of a disturbing body (Poisson’s Theorem). The potential fields are sampled adequately at a limited expenditure of time and effort in the field by utilizing the geometry of two‐dimensional bodies. The major limitation to the analysis is the removal of regional gradients and the estimation of the base levels of anomalies. Combined gravity and magnetic surveys were conducted over six diabase bodies in the Triassic Basin of Pennsylvania. The results of these surveys indicate a resultant direction of magnetization given approximately by: declination 2° W, inclination 41 degrees below the horizon. The corresponding direction of natural remanent magnetization has a declination of 1° W and an inclination of 28 degrees. The ratio of remanent to induced magnetization for the diabase is approximately two. These results have been used to provide a better interpretation of magnetic survey data over a magnetite deposit in the Triassic Basin.

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