Geology Reference
In-Depth Information
reactions that form new ferromagnetic
minerals by alteration of existing minerals
or precipitation;
Detrital remanent magnetization
(DRM),
which forms during the process of accumula-
tion and lithification of sediments containing
detrital ferromagnetic minerals.
In the next chapters, we shall apply these
concepts to the study of the Earth's magnetic field
in the geologic past, which furnishes the basic
class of data used in plate kinematics.
magnetic field has strength
F
D
40,000 nT and
inclination
I
D
35
ı
, determine the maximum
torque exerted on the needle;
4. Determine the maximum magnitude of dipolar
interaction energy for hematite;
References
Butler RF (1992) Paleomagnetism: magnetic domains to
Geologic terranes. Blackwell Scientific Publications,
Boston, p 238
de Boer CB, Mullender TAT, Dekkers MJ (2001) Low-
temperature behaviour of haematite: susceptibility and
magnetization increase on cycling through the Morin
transition. Geophys J Int 146:201-16
Feynman RP, Leighton RB, Sands M (2006) The Feynman
lectures on physics, The definitive edition, vol 2, Chap-
ter 34. Pearson Education Inc., California Institute of
Technology, Pasadena, CA
Harrison RJ, Putnis A (1996) Magnetic properties of the
magnetite-spinel solid solution: curie temperatures,
magnetic susceptibilities, and cation ordering. Am
Miner 81:375-84
Hunt CP, Moskowitz BM, Banerjee SK (1995) Magnetic
properties of rocks and minerals. In: Ahrens TJ (ed)
Rock physics and phase relations: a handbook of
physical constants, 3rd edn. AGU, Washington, DC,
pp 189-204. doi:
10.1029/RF003p0189
Panofsky WKH, Phillips M (2005) Classical electricity
and magnetism. Courier Dover, Mineola, NY
Problems
1. Calculate the maximum diamagnetic magneti-
zation of 1 kg Hydrogen in an external field
B
with magnitude
B
D
0.1 T;
2. The saturation magnetization per unit mass
for hematite is
M
s
Š
0.48 A m
2
kg
-1
. Assum-
ing that a hematite assemblage is formed by
10 m SD grains, determine the magnetic
moment of a single grain at saturation;
3. A compass needle having volume
V
D
20
10
-9
m
3
has magnetization
M
D
300 kA/m.
Assuming that at some location theEarth's
