Magnetic methods and the timing of geological processes
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
Downloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
Magnetic methods and the timing of geological processes
L. JOVANE1*, L. HINNOV2, B. A. HOUSEN3 & E. HERRERO-BARVERA4
1
Instituto Oceanográfico da Universidade de São Paulo, Fisica, Geoquimica e Geologia,
Praça do Oceanográfico 191, São Paulo, São Paulo 05508-120, Brazil
2
John Hopkins University, Earth and Planetary Sciences, 3400 N. Charles Street,
Baltimore, Maryland 21218, USA
3
Department of Geology, Western Washington University, 516 High St.,
Bellingham, Washington 98225, USA
4
University of Hawaii at Manoa, Hawaii Institute of Geophysics and Planetology,
Honolulu, Hawaii 96822, USA
*Corresponding author (e-mail: jovane@usp.br)
Abstract: Magnetostratigraphy is best known as a technique that employs correlation among
different stratigraphic sections using the magnetic directions that define geomagnetic polarity
reversals as marker-horizons. The ages of the polarity reversals provide common tie points
among the sections, allowing accurate time correlation. Recently, magnetostratigraphy has
acquired a broader meaning, now referring to many types of magnetic measurements within a stra-
tigraphic sequence. Many of these measurements provide correlation and age control not only for
the older and younger boundaries of a polarity interval, but also within intervals. Thus, magnetos-
tratigraphy no longer represents a dating tool based only on the geomagnetic polarity reversals, but
comprises a set of techniques that includes measurements of all geomagnetic field parameters,
environmental magnetism, rock magnetic and palaeoclimatic change recorded in sedimentary
rocks, and key corrections to magnetic directions related to geodynamics, tectonics and
diagenetic processes.
Discovery of geomagnetic reversals motions of the ocean floor. The oceanic magnetic
anomalies are related to the magnetization of the
Over the past century numerous methodologies oceanic basalts that cool down while spreading
have been developed to detect time variations of the from mid-oceanic ridges, and can be used in combi-
geomagnetic field and environmentally significant nation with geomagnetic field polarity sequences
magnetic properties in rocks. These methods com- from rocks found on land to further develop a
prise measurements of natural remanence, magnetic globally extensive GPTS (Heirtzler et al. 1968).
susceptibility, demagnetization and induced artifi- Opdyke (1972) first integrated magnetostratigra-
cial magnetizations. Brunhes (1906) and Matuyama phy and biostratigraphy for Plio-Pleistocene marine
(1926) were among the first to recognize that old sediments, and since that time biostratigraphic
rocks have inclination values that are very different information has been increasingly used for corre-
from today’s values, and sometimes of opposite lation of the observed polarity sequences in sedi-
polarity to the present-day magnetic field. Accord- mentary rocks with the appropriate part of the
ing to Matuyama (1926), these changes represent radioisotope-calibrated GPTS. Subsequently, Alva-
reversals in the polarity of the ancient geomagnetic rez et al. (1977) recognized sets of magnetic polar-
field. Cox et al. (1963) recognized that these polar- ity reversals within the Cenozoic Gubbio (Italy)
ity reversals were global events, and that, by com- sedimentary sequence. William Lowrie studied the
bining palaeomagnetic and geochronologic data, a geological and physical processes that permit
sequence of geomagnetic field reversals could be pelagic sediments to keep magnetization and defined
constructed. This led directly to the development the magnetostratigraphy of those Italian sections
of the Geomagnetic Polarity Time Scale (GPTS). (Lowrie et al. 1982), allowing the scientific commu-
Vine & Matthews (1963), using data acquired nity to build and further refine the GPTS (Cox et al.
during marine cruises, recognized that magnetic 1963; Heirtzler et al. 1968; LaBreque et al. 1977;
anomalies had a symmetrical pattern with respect Berggren et al. 1985; Cande & Kent 1992, 1995;
to the mid-ocean ridges, and that there was a rela- Huestis & Acton 1997; Singer et al. 2002; Channell
tionship between geomagnetic field reversals and et al. 1995; Malinverno et al. 2012; Ogg 2012).
From: Jovane, L., Herrero-Bervera, E., Hinnov, L. A. & Housen, B. A. (eds) 2013. Magnetic Methods and the
Timing of Geological Processes. Geological Society, London, Special Publications, 373, 1– 12.
First published online April 25, 2013, http://dx.doi.org/10.1144/SP373.17 # The Geological Society of London 2013.
Publishing disclaimer: www.geolsoc.org.uk/pub_ethicsDownloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
2 L. JOVANE ET AL.
TimeScale Creator chart
Geomagnetic
Standard Chronostratigraphy Polarity
Primary
Ma Period Epoch Age/Stage
0 Holocene Tarantian 50 C22
Ionian C1
1 51
Quaternary Calabrian
Pleistocene C23
2 Gelasian C2 52
3 53 Eocene Ypresian
Piacenzian
C2A
4 Pliocene 54
Zanclean C24
5 C3 55
6 56
Messinian
C3A
7 57
C3B Thanetian
C25
Paleogene
8 C4 58
9 59
Tortonian C4A
10 60 Selandian C26
Paleocene
11 C5 61
12 62
C5A C27
Neogene Serravallian C5AA
13 63
C5AB Danian
C5A C28
14 Miocene 64
C
Langhian C5A
15 65 C29
D
C-Sequence
C5B
16 66
C5C
17 67 C30
C5D
18 68 Maastrichtian
Burdigalian
19 C5E 69
C31
20 70
C6A
21 71
C6AA
Aquitanian
22 C6B 72
C32
23 73
C6C
24 74
C-Sequence
C7
25 C7A 75
Chattian
26 C8 76
27 77 Campanian
C9
28 78
Oligocene C33
29 C10 79
30 C11 80
31 Rupelian 81
32 C12 82
Late
Cretaceous
33 83
34 C13 84
Santonian
35 C15 85
Priabonian
36 C16 86
Cretaceous Normal Super-Chron ("Cretaceous Quiet Zone")
Paleogene
37 87 Coniacian
C17
38 88
39 Bartonian 89
C18
40 90
41 C19 91 Turonian
C34
42 Eocene 92
43 93
C20
44 Lutetian 94
45 95
46 96
Cenomanian
47 TimeScale Creator chart C21 97
48 Geomagnetic 98
Standard Chronostratigraphy Polarity
49 Ypresian 99
Primary
C22
Ma Period Epoch Age/Stage Early AlbianDownloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
MAGNETOSTRATIGRAPHY: ONLY A DATING TOOL? 3
Today, geomagnetic reversals are routinely demonstrates the occurrence of reversals (Glatzma-
recognized along stratigraphic sections composed ier & Roberts 1995; Kuang & Bloxham 1997). The
of sedimentary (marine or continental) or volcanic main theory relates reversals to internal fluid
materials. To determine a polarity stratigraphy, the instability of the Earth’s outer core. In this region
sediment or rock must first contain a record of the of the core, convective movements and complex
geomagnetic field that is generally acquired at vortices are created within tangent cylinders, that
the time of emplacement. In order to measure the is, cylinders that are pretended coaxial movements
original magnetization that records the geomagnetic in relation to the Earth’s rotation axis, and tangent
field polarity at the time of formation of the rock, to the inner core/outer core boundary with their
sample direction must be measured in the field projection on Earth surface at 79.18 latitude. The
(i.e. in situ). The capacity of a rock to maintain its thermal and compositional convection processes at
own magnetic field and resist demagnetization is the core-mantle boundary influence the geodynamo
related to the coercivity of its magnetic minerals. with long-term variations (.105 years) of intensity,
There are different ways by which rocks can inclination and declination (Olson et al. 2010). This
record a natural remanent magnetization (NRM) in organized motion evolves chaotically with the mag-
the presence of an external magnetic field (e.g. the netic field produced by the electromagnetic dynamo
geomagnetic field; Kodama 2012): (1) thermorema- growing, decaying and occasionally flipping in
nent magnetization (TRM) is acquired when a rock the opposite direction (Gubbins & Bloxham 1985,
cools down below the Curie temperature of its mag- 1987; Bloxham & Jackson 1992; Olson & Aurnou
netic minerals; (2) chemical remanent magnetiza- 1999; Jackson et al. 2000; Hulot et al. 2002;
tion (CRM) is acquired when a new magnetic Aurnou et al. 2003; Wardinski & Holme 2006). The
mineral grows after the rock is formed and estab- geomagnetic reversals occur on the entire globe,
lishes its own magnetization; (3) viscous remanent also near the tangent cylinder and polar regions
magnetization (VRM) is attained in an ambient (Jovane et al. 2008). There are also other theories
field for magnetic relaxation during time; (4) iso- to explain reversals, for example, one in which geo-
thermal remanent magnetization (IRM) occurs in magnetic reversals are linked to extraterrestrial
nature when rocks are struck by lightning and are impacts (Muller & Morris 1986).
submitted to a magnetic field larger that their coer-
civity; and, the most important in sediments, (5) det-
rital remanent magnetization (DRM) is acquired Magnetostratigraphy and the geomagnetic
when depositional magnetic grains align themselves polarity time scale
with the geomagnetic field as they are settling
through the water column or are in unconsolidated At its most fundamental level, magnetostratigra-
sediment. Depositional magnetic grains deposited phy documents the geological record of polarity
on the seafloor are then able to lock in and retain changes of the geomagnetic field. The individual
the original magnetization in the direction of the normal (black) and reversed (white) (Fig. 1) polarity
geomagnetic field during the initial consolidation intervals are known as chrons and typically range
of sediments (Tauxe et al. 2006; Tauxe & Yamazaki in duration from 10 kyr to 10 Myr. The transition
2007). However, in some deep-sea sediments, a from a reversed-polarity chron to a normal-polarity
time delay of magnetization has been occasionally chron and vice-versa is very short (+5 kyr). This
observed and is attributed to very low sedimenta- allows a numerical age to be assigned to each rock
tion rates and delayed lock-in below the sedi- unit containing a polarity reversal within a strati-
ment –water interface (Verosub 1977; Suganuma graphic succession. Since polarity reversals effec-
et al. 2011). This magnetization acquired near tively occur simultaneously over the whole surface
but not directly at the time of deposition is referred of the Earth, they can be used for global time corre-
to as post-depositional remanent magnetization lation. Shorter periods of opposing polarity within
(pDRM). There are also some conditions in which a chron are called, depending on duration, ‘sub-
magnetic crystals produced by magnetotactic bac- chrons,’ ‘microchrons’ and ‘cryptochrons’ (Cande
teria may record the geomagnetic field (Petersen & Kent 1992). Longer periods with dominant sin-
et al. 1986; Housen & Moskowitz 2006; Vasiliev gle polarity are called ‘superchrons’ or ‘mega-
et al. 2008; Yamazaki 2009; Roberts et al. 2011, chrons,’ also depending on duration (Opdyke &
2012; Jovane et al. 2012). Channell 1996).
The cause of the geomagnetic field reversals is Chrons are conventionally labelled and named
still unknown, although geodynamical modelling after the corresponding seafloor spreading magnetic
Fig. 1. Example of the GPTS for the past 100 million years, from TSCreator 5.0 (www.tscreator.org). Courtesy of
J. Ogg. (2012).Downloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
4 L. JOVANE ET AL.
anomaly number (Cande & Kent 1992). Chron num- Such geomagnetic excursions have been
ber is usually suffixed by the letter n or r, depending reported in geological recorders such as lava flows
on whether the dominant magnetic polarity is of various ages in different parts of the world as
normal or reversed, and is prefixed, for instance, well as from deep-sea, lake sediment and sedimen-
by the letter C for Cenozoic, or M for Mesozoic tary rocks. This type of geomagnetic feature gener-
(Gee & Kent 2007). The most recent reversal of ally are observed to start with a sudden and often
the geomagnetic field occurred 781 kyr ago and is fairly smooth movement of the virtual geomagnetic
the boundary between Brunhes (C1n) and Matu- poles (VGP) toward equatorial latitudes. The VGP
yama (C1r) Chrons. Other normal and reversed may then return almost immediately, or it may
chrons, Gauss (C2n) and Gilbert (C2r), contain dis- cross the equator and move through latitudes in
tinctive subchrons, such as the Olduvai Subchron the opposite direction before travelling back again
(C1r.2n) within the Matuyama Chron. The GPTS is to resume a near-axial position. The term ‘excur-
continually updated to provide the most accurately sion’ was defined to describe a VGP movement of
known ages for the chron boundaries (e.g. Fig. 1). more that 408 from the geographic pole for inter-
Vector component diagrams (Zijderveld 1967) mediate pole positions that end up with a return of
are used display stepwise demagnetization data. the Earth’s field to its pre-existing polarity (Barbetti
When a series of rock layers shows the same sign & McElhinny 1976). During an excursion, the
of inclination of the characteristic remanent magne- dynamo does not establish itself in the opposite
tization (ChRM), it is called a magnetozone (or polarity. Defined in this way, excursions are dis-
magnetostratigraphic unit), because within this tinguished from secular variation (when the VGP
interval a single polarity is constant. Magnetostrati- colatitude is 108 , u ,408) and from short polarity
graphy correlates magnetozones to the GPTS. episodes, which is a term applied when the opposite
Namely, inclination, declination and intensity of polarity (u is ,408 or .1408) persists sufficiently
the ChRM for each sample are examined through long for at least one oscillation in the strength of
a principal component analysis (PCA) of demagne- the main dipole (about 104 years, Jacobs 1984).
tization steps (Kirschvink 1980). Demagnetization Several short and almost complete changes in
can be accomplished in different ways for different geomagnetic inclination have occurred within the
magnetic components. Stepwise thermal (TH) and present-day Brunhes Chron. These rapid and global
alternating field (AF) demagnetizations are the geomagnetic events are called ‘excursions’ or
most popular methods. Chemical and pressure ‘aborted reversals’ (Lund et al. 2006; Laj & Chan-
demagnetization methods can also be applied to nell 2007). Among these excursions, the Laschamp
erase unwanted secondary components. (40– 41 ka), Blake (c. 115–120 ka) and the Prin-
The calculated PCA inclination values some- gle Falls (c. 211–218 ka) are the most impor-
times do not represent the true inclination of the tant geomagnetic events because they have been
geomagnetic field at that time of the formation or widely documented (e.g. Valet & Meynadier 1998;
deposition of the rock unit (Butler 1992; Tauxe Guyodo & Valet 1999; Valet et al. 2008). Because
2010). This problem is related to geological excursion events have been recognized further
factors that can be resolved using other magnetic back in time (e.g. Handschumacher et al. 1988;
methods. These factors may be related to diagenetic Sager et al. 1998; Tivey et al. 2006), we can infer
compaction or rotation of tectonic plates and tilt of that they occurred probably also during older
structural blocks. chrons. These excursions, sometimes called tiny
wiggles (e.g. Lanci & Lowrie 1997), cannot yet be
used as time constrain.
Beyond classical magnetostratigraphy
Relative palaeointensity
Dating with other recorded features of the geomag-
netic field can also be undertaken, as follows. The Earth’s magnetic field can be simplified as a big
dipole with the poles at the geographical poles,
Excursions and aborted reversals which is called the geocentric axial dipole (GAD).
The behaviour of the geomagnetic field is complex
It is very well known from palaeomagnetic records and is related not only to the GAD but also to
today that, in addition to polarity changes, the other components that change at different time-
Earth’s magnetic field has experienced changes scales: years (secular variation), millennia (excur-
from its regular near-axial configuration for brief sions) and millions of years (reversals) (Gee &
periods of time without establishing, and perhaps Kent 2007).
not even approaching, a reversed state of the palaeo- Several short and almost complete changes in
field. These types of behaviour are called geomag- geomagnetic inclination have occurred within the
netic excursions or ‘aborted reversals’. present-day Brunhes Chron. These rapid andDownloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
MAGNETOSTRATIGRAPHY: ONLY A DATING TOOL? 5
global geomagnetic events are called ‘excursions’ palaeointensity. Measurements of palaeointensity
or ‘aborted reversals’ (Lund et al. 2006; Laj & in different geological sequences (e.g. lava flows,
Channell 2007). An important long-term (105 year) or marine or lake sediments) show a consistent
variation of spherical parameters (inclination, decli- pattern, allowing the reconstruction of a relative
nation and intensity) of the geomagnetic field is the palaeointensity curve for the past 2 myr (Fig. 2;
secular variation (Valet et al. 2008), which includes Sint-2000; Valet et al. 2005). Sint-2000 is a stack
geomagnetic jerks, westward drift and palaeointen- curve of independent palaeointensity records from
sity. Geomagnetic jerks are abrupt changes in one various latitudes for the last 2 myr. It is possible
of the geomagnetic components related to inner to date a geological sequence by correlating the
core flow patterns or major earthquakes (Mandea reference Sint-2000 intensity record to the palaeoin-
et al. 2000; Florindo et al. 2005). The secular vari- tensity record of the studied sequence. This is poss-
ation, which is not constant and uniform on the ible only when the magnetic minerals along the
Earth, is mainly related today to a westward drift section are relatively uniform (King et al. 1983;
of about 0.28 per year since 1400 AD, and an east- Valet & Meynadier 1998), and when the magnetic
ward drift from 1000 to 1400 AD (Dumberry & intensity has been previously normalized for the
Finlay 2007). The variation in intensity of the geo- concentration and grain-size of magnetic material
magnetic field through geological time is known as (thus ‘relative’), which may be climatically driven
Relative paleointensity
arbitrary units arbitrary units
0 0 0
Laschamp
Blake 0.1
Iceland Basin
Pringle Falls 0.2 0.2 0.2
0.3
0.4 0.4 0.4
Calabrian Ridge, Tarrafal 0.5
Big Lost 0.6
0.6 0.6
0.7
Brunhes-Matuyama
0.8 0.8 0.8
Kamikatsura 0.9
Santa Rosa ODP Sites 983-984
Upper Jaramillo 1.0 1
Punaruu 1.1
Cobb Mountain 1.2 1.2
Bjorn
1.3
1.4 1.4
Gardar
1.5
Gilsa
1.6 1.6
1.7
Upper Olduvai
1.8 1.8
1.9
Lower Olduvai
2.0 2
Age (ka) Age (ka) Sint-2000
Fig. 2. Polarity column showing the position of the successive excursions and reversals with respect to the fluctuations
of dipole field intensity derived from the composite Sint-2000 record and from ODP sites 983 (red line) and 984 (blue
line) in the northeastern Atlantic Ocean (arbitrary units increasing toward right) (Guyodo & Valet 1999; Valet et al.
2008).Downloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
6 L. JOVANE ET AL.
(e.g. Valet & Herrero-Barvera 2000; Channell et al. by geomagnetic components at the time of depo-
2002; Yamazaki 2008). It is worth noting that severe sition or solidification (Tauxe 2010). Consequently,
declines in relative intensity coincide with geomag- magnetic susceptibility may not be isotropic, giv-
netic reversals and excursions (Fig. 2; Valet et al. ing different values when measured in different
2008). directions. In such cases, the anisotropy of magnetic
Another application is the scatter of inclination susceptibility (AMS) is calculated as a tensor by
and declination on a sphere, or angular dispersion comparing the magnetic susceptibility values in
(S) (e.g. Jovane et al. 2008). S is related to latitude, three perpendicular directions, which produce a
with higher values near the poles, and may indicate matrix representing the ellipsoid of the magnetic
the geomagnetic stability of core vortices (Olson & susceptibility (e.g. Hrouda 1982). This ellipsoid
Aurnou 1999; Aurnou et al. 2003). of the magnetic fabric can be spherical, oblate
(flattened) or prolate (cigar-shaped) providing in-
Tectonics and deformation formation, for example, on the direction of a palaeo-
current (e.g. Ellwood & Whitney 1980) or lava flow
While palaeomagnetic data have been used for a (e.g. Stacey 1960; Ellwood 1978), strain patterns
long time to examine plate-scale to regional/local (e.g. Goldstein 1980), fabric/structure of granites
tectonic and structural problems (e.g. Irving 1963, (e.g. Ellwood & Whitney 1980) and the degree of
Beck 1981; Van der Voo 1988), a number of compaction of strata studying the relation between
recent studies have combined magnetostratigra- inclination shallowing and oblation of the fabric
phic and palaeomagnetic analyses to examine (e.g. Tan & Kodama 2002).
timing and temporal variations in structural pro-
cesses. This approach is made possible by the Environmental magnetism
collection of more samples per site (or single geo-
logical bed) and more sites than is typical for stan- Environmental magnetism is used to identify
dard magnetostratigraphic studies (e.g. Zhao et al. and characterize magnetic mineralogy, and pro-
2001; Liu et al. 2003; Titus et al. 2011). This tech- vides constraints for interpreting palaeomagnetic
nique has the potential to test velocity models of results and in understanding the factors that control
plate-margin and fault-zone deformation that are environmental change. Environmental magnetic
based primarily on Global Positioning System measurements are inexpensive, rapid and non-
(GPS) data (e.g. McCaffrey 2005). GPS defor- destructive, and provide fundamental information
mation studies utilize short (decades at most) on the size, abundance and composition of magnetic
time-series of GPS displacement data and their pre- minerals (Verosub & Roberts 1995; Kodama 2012;
dictions of vertical-axis rotation can be compared Liu et al. 2013). These measurements can be per-
with observations obtained from palaeomagnetic formed along a sedimentary sequence at high-
data (e.g. Titus et al. 2011). resolution and include (1) magnetic susceptibility,
Magnetic inclination and declination track the and artificial remanences; (2) anhysteretic remanent
position of palaeopoles through geological time magnetization (ARM); (3) isothermal remanent
(Irving 1956). A reconstructed sequence of palaeo- magnetization (IRM) and back-field isothermal
poles for a plate is known as an Apparent Polar remanent magnetization (BIRM); and (4) coerci-
Wander Path (APWP). We define the APWP tive-dependent parameters (S-ratio and ‘hard’ IRM
through study of ChRM, which points to the VGP referred to as HIRM).
of the original position of a rock at the time it was Low-field magnetic susceptibility (x ¼ nor-
formed. APWPs of the major tectonic plates have malized for weight, k ¼ normalized for volume)
been reconstructed through much of Phanerozoic represents how much magnetization (m) a material
time (e.g. Besse & Courtillot 2002; Kearey et al. retains when a magnetic field (H ) is applied
2009), but there are still large uncertainties in the (Table 1). Thus it is a complex parameter reflecting
APWPs of minor plates and in reference poles the sum of magnetic materials, such as ferromag-
(McElhinny & McFadden 2000). netic sensu lato (e.g. magnetite), antiferrimagnetic
Magnetic anisotropy studies can help define (e.g. hematite) and non-magnetic materials, such
shallowing effects related to diagenetic compaction, as paramagnetic (e.g. silicates or clays) and diamag-
flow direction during deposition or cooling and netic (e.g. quartz or carbonate). Results from low-
deformation of rocks owing to tectonic stresses. field magnetic susceptibility must be interpreted
The larger datasets generated from these studies with caution since it can be related to numerous
can be utilized to test and resolve other important processes.
aspects of how sedimentary rocks record the geo- Anhysteretic remanent magnetization activates
magnetic field. The inclination, declination and only the finest magnetic minerals, frequently
intensity of the DRM of sedimentary magnetic single domain (SD) grains, which do not have a
grains, and the TRM of lava flows, can be affected domain wall and are uniformly magnetized. It is,Downloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
MAGNETOSTRATIGRAPHY: ONLY A DATING TOOL? 7
Table 1. Units and conversions in the Système Internationale d’unités (SI) and the old CGS
CGS SI
Energy 107 erg 1 joule (J)
Force (F) 105 dyne 1 Newton (N)
Current (I ) 0.1 adamp 1 ampere (A)
Magentic Inducion (B) 104 gauss (G) 1 Tesla (T)
Magnetic Field (H ) 4p × 1023 oersted (Oe) 1 A m21
Magnetic Moment (M ) 103 emu 1 A m2
Magnetization/volume (m) 1023 emu (¼G cm23) 1 A m21
Magnetization/mass (J ) 1 emu g21 or G cm23 g21 1 A m2 kg21
Magnetic susceptibility/volume (k) Dimensionless Dimensionless
Magnetic susceptibility/mass (x) 1023 cm3 g21 1 m3 kg21
From Butler (1992) and Collinston (1983).
consequently, a proxy for the concentration of fine sequences can be evaluated as time series and
magnetite of eolian, biogenic or impactoclastic related to palaeoclimatic and palaeoenvironmental
origin, or from other environmental processes. Iso- change. In particular, palaeoclimate change at
thermal remanent magnetization activates all mag- 105 –106 year scales – often resolved in the sedi-
netic grains up to saturation (also called SIRM or mentary record – has been strongly modulated by
Mrs) that is usually at 1 T or 900 mT (Table 1). astronomically forced insolation (e.g. Berger 1988;
IRM, therefore, is the main proxy for magnetic con- Laskar et al. 2004, 2011; Table 2). The record of
centration. The ratio between ARM and IRM astronomical forcing frequencies in palaeomagnetic
(ARM/IRM900) provides a proxy for magnetic proxies can be used as a tool to perform astronomi-
grain size. Then, smaller IRMs can be applied back- cal tuning and develop continuous timescales along
wards to IRM, which are called back-field IRM stratigraphic sequences (Hinnov & Hilgen 2012).
(BIRM), to produce IRM ratios that supply infor-
mation on magnetic composition. These are the
so-called S-ratios (King & Channell 1991) and Organization of this special volume
HIRMs (imparted at 300 and 100 mT, respectively).
They are calculated as, for example, S-ratio300 ¼ Following three conference sessions entitled ‘Mag-
BIRM300/IRM900, S-ratio100 ¼ BIRM100/IRM900, netostratigraphy: not only a dating tool’ and pre-
HIRM300 ¼ (IRM900 + BIRM300)/2 or HIRM100 ¼ sented at the AGU Meeting of Americas (Foz de
(IRM900 + BIRM100)/2 to indicate the different Iguaçu, Brazil) in 2010 and AGU Fall Meetings
responses of high-coercivity magnetic minerals. The 2010, 2011 (San Francisco, USA), we decided to
presence of hematite can be determined with the assemble the presentations into a Special Publi-
proxy IRM900@AF120 mT for the concentration cation entitled Magnetic Methods and the Timing
of hematite by AF demagnetizing the IRM900 of Geological Processes. In this volume, we
step at 120 mT (Larrasoaña et al. 2003). Liu present research that includes innovations in classi-
et al. (2007) also proposed the L-ratio (IRM900 + cal magnetostratigraphy and emerging techniques
BIRM300)/(IRM900 + BIRM100) to define how the that use sequential rock magnetic measurements to
hardness of hematite can affect HIRM and the define chronology in stratigraphy. We introduce
S-ratio. applications that use magnetic direction and geo-
Environmental magnetic records obtained by magnetic polarity reversals to infer geodynamo
finely sampled measurements along sedimentary processes, tectonics, diagenesis and climate change.
Table 2. Periods and relative amplitudes of the main astronomical forcing cycles for 0 – 10 Ma (Laskar et al.
2004; Hinnov & Hilgen 2012). The frequencies and relative amplitudes change over different time intervals,
and relative amplitudes change additionally as the result of climatic filtering
Astronomical parameter Period in kiloyears (relative amplitude)
Orbital eccentricity 405 (1.0) 131 (0.43) 124 (0.56) 99 (0.48) 95 (0.74)
Obliquity (tilt) 53.04 (0.34) 40.80 (1.0) 40.11 (0.33) 39.45 (0.42) 29.75 (0.16)
Precession index 23.61 (1.0) 22.33 (0.87) 19.07 (0.45) 19.12 (0.69) 16.44 (0.08)Downloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
8 L. JOVANE ET AL.
Finally, we present examples of astronomical forc- in press). Finally, VGP trajectories measured on the
ing of environmental magnetism in the sedimentary Lower Cretaceous Serra Geral volcanic sequence
record, and their utility in defining high-resolution are interpreted to indicate anisotropy in the Earth’s
timescales. interior (Caminha-Maciel & Ernesto 2012).
Part 1: integrated magnetostratigraphy Part 4: palaeoclimatic change from rock
When integrated with biostratigraphy, cyclostrati- magnetic proxies
graphy, chemostratigraphy and geochronology, The studies in this section resolve astronomical
magnetostratigraphy provides valuable timescale timescales of palaeoclimatic change using rock
information. In this section, modern integrated magnetism stratigraphy evaluated from a wide
magnetostratigraphy is demonstrated with marine variety of marine environments: Plio-Pleistocene
Cenozoic studies. New Oligocene–Miocene magne- marginal marine, Cretaceous carbonate platform,
tostratigraphy from the equatorial Pacific pinpoints Permian lower slope and basinal carbonates,
the Oligocene –Miocene transition at the base of Permo-Carboniferous glaciogenic rhythmites, and
C6Cn.2n, and identifies three new excursions (Gui- Ordovician shallow shelf limestone/mudstone.
dry et al. 2012). New work is presented on the The Plio-Pleistocene study astronomically tunes a
Eocene climatic optimum interval (50–55 Ma) and magnetic susceptibility series from a sedimentary
Late Eocene –Oligocene transition into the Ceno- section in northern Italy that otherwise exhibits no
zoic icehouse (c. 33.5 Ma) from Integrated Ocean cyclicity (Gunderson et al. 2012). The Cretaceous
Drilling Progam sites and Italian sections (Firth study (Hinnov et al., this volume, in press) finds
et al. 2012; Savian et al. 2013; Jovane et al. 2013), that ARM cyclicity is independent from host car-
and a composite integrated magnetostratigraphic bonate platform cycles in northeastern Mexico; the
sequence from Italy is provided for the entire former is linked to a precession-forced eolian
Palaeogene Period (Coccioni et al. 2012). dust flux and the latter to much lower frequency sea-
level fluctuations. Ellwood et al. (2012a) develop
Part 2: dating tectonic processes with obliquity-tuned ‘floating timescales’ for magnetic
magnetic methods susceptibility variations along Middle Permian sec-
tions, Texas, to assess sedimentation rates and dur-
The evolution of palaeomagnetic declination in ations of geological events. Franco & Hinnov
Chinese continental stratigraphy reveals block (2012) evaluate anisotropy of magnetic suscepti-
rotation, uplift and basin infilling related to the Cen- bility in Brazilian Permocarboniferous glacial
ozoic India–Asia collision, as discussed by three rhythmites as a palaeoclimate indicator. Finally,
papers in this section (Yan et al. 2012a, b; Fang the cyclic Ordovician Kope Formation, USA, is
et al. 2012). The timing of these declination evaluated for astronomical frequencies through
changes is constrained by magnetic reversal strati- analysis of a composite high-resolution magnetic
graphy. A fourth paper (Zhao et al. 2013) analyses susceptibility series (Ellwood et al. 2012b).
tectonic-driven sedimentation change in the Nan-
kai Trough, Japan, with the assistance of integrated We gratefully acknowledge the review of G. Acton, M.
magnetostratigraphy. Ernesto, A. Malinverno and X. Zhao.
Part 3: relative palaeointensity for dating References
geological sequences Alvarez, W., Arthur, M. A., Fischer, A. G., Lowrie,
W., Napoleone, G., Premoli-Silva, I. & Rog-
In this section, the palaeomagnetic secular variation genthen, W. M. 1977. Upper Cretaceous-Paleocene
recovered from a Holocene Lake in Indonesia is magnetic stratigraphy at Gubbio, Italy. V. Type
compared with a recent geomagnetic model for section for the late Cretaceous-Paleocene geomagnetic
0–3 ka, and used to evaluate radiocarbon-based reversal time scale. Geological Society of America
chronologies (Haberzettl et al. 2012). A new evalu- Bulletin, 88, 383– 389.
ation of the Pringle Falls lacustrine sequence con- Aurnou, J. M., Andreadis, S., Zhu, L. & Olson, P. L.
firms the clockwise loop of the VGP around the 2003. Experiments on convection in Earth’s core
globe associated with the Pringle Falls Excursion tangent cylinder. Earth and Planetary Science
Letters, 212, 119– 134.
(Herrero-Bervera & Cañón-Tapia 2012). The Barbetti, M. F. & McElhinny, M. W. 1976. The Lake
Laschamp, Skalamaelifell and Blake excursions, Mungo geomagnetic excursion. Philosophical Trans-
detected in sediments from offshore Queensland, actions Royal Society of London, A281, 515– 540.
Australia, are applied as chronostratigraphic con- Beck, M. E., Burmester, R. F. & Schoonover, R.
straints (Herrero-Bervara & Jovane, this volume, 1981. Paleomagnetism and Tectonics of theDownloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
MAGNETOSTRATIGRAPHY: ONLY A DATING TOOL? 9
Cretaceous Mt. Stuart Batholith of Washington: trans- Dumberry, M. & Finlay, C. C. 2007. Eastward and west-
lation or Tilt? Earth and Planetary Science Letters, ward drift of the Earth’s magnetic field for the last three
56, 336–342. millennia. Earth and Planetary Science Letters, 254,
Berger, A. 1988. Milankovitch theory and climate. 146– 157.
Reviews of Geophysics, 26, 624–657. Ellwood, B. B. 1978. Flow and emplacement direction
Berggren, W. A., Kent, D. V., Flynn, J. J. & Van Cou- determined for selected basaltic bodies using magnetic
vering, J. A. 1985. Cenozoic geochronology. Geologi- susceptibility anisotropy measurements. Earth Plane-
cal Society of America Bulletin, 96, 1407–1418. tary Science Letters, 41, 254–264.
Besse, J. & Courtillot, V. 2002. Apparent and true polar Ellwood, B. B. & Whitney, J. A. 1980. Magnetic fabric
wander and the geometry of the geomagnetic field over of the Elberton granite, Northeast Georgia. Journal of
the last 200 Myr. Journal of Geophsical Research, 107, Geophysical Research, 85, 1481– 1486.
2300. Ellwood, B. B., Lambert, L. L. et al. 2012a. Magnetos-
Bloxham, J. & Jackson, A. 1992. Time-dependent tratigraphy susceptibility for the Guadalupian series
mapping of the magnetic field at the core –mantle GSSPs (Middle Permian) in Guadalupe Mountains
boundary. Journal of Geophysical Research, 97, National Park and adjacent areas in West Texas. In:
19 537 –19 563. Jovane, L., Herrero-Bervera, E., Hinnov, L. A.
Brunhes, B. 1906. Recherches sur la direction d’aimanta- & Housen, B. A. (eds) Magnetic Methods and the
tion des roches volcaniques. Journal of Physics IV, 5, Timing of Geological Processes. Geological Society,
705–724. London, Special Publications, 373, first published on
Butler, R. F. 1992. Palaeomagnetism, Magnetic Domains August 14, 2012, doi: 10.1144/SP373.1.
to Geologic Terranes. Blackwell Scientific, Boston, MA. Ellwood, B. B., Brett, C. E., Tomkin, J. H. & Macdo-
Caminha-Maciel, G. & Ernesto, M. 2013. Character- nald, W. D. 2012b. Visual identification and quantifi-
istic wavelengths in VGP trajectories from magneto- cation of Milankovitch climate cycles in outcrop: an
stratigraphic data of the Early Cretaceous Serra Geral example from the Upper Ordovician Kope Formation,
lava piles, southern Brazil. In: Jovane, L., Herrero- Northern Kentucky. In: Jovane, L., Herrero-
Bervera, E., Hinnov, L. A. & Housen, B. A. (eds) Bervera, E., Hinnov, L. A. & Housen, B. A. (eds)
Magnetic Methods and the Timing of Geological Pro- Magnetic Methods and the Timing of Geological Pro-
cesses. Geological Society, London, Special Publi- cesses. Geological Society, London, Special Publi-
cations, 373, first published on March 25, 2013, doi: cations, 373, first published on August 14, 2012, doi:
10.1144/SP373.15. 10.1144/SP373.2.
Cande, S. C. & Kent, D. V. 1992. A new geomagnetic Fang, X., Liu, D., Song, C., Dai, S. & Meng, Q. 2012.
timescale for the Late Cretaceous and Cenozoic. Oligocene slow and Miocene– Quaternary rapid defor-
Journal of Geophysical Research, 97, 13 917– 13 951. mation and uplift of the Yumu Shan and North Qilian
Cande, S. C. & Kent, D. V. 1995. Revised calibration of Shan: evidence from high-resolution magnetostratigra-
the Geomagnetic Polarity Time Scale for the Late Cre- phy and tectonosedimentology. In: Jovane, L.,
taceous and Cenozoic. Journal of Geophysical Herrero-Bervera, E., Hinnov, L. A. & Housen,
Research, 100, 6093–6095. B. A. (eds) Magnetic Methods and the Timing of Geo-
Channell, J. E. T., Erba, E., Nakanishi, M. & Tamaki, logical Processes. Geological Society, London,
K. 1995. Late Jurassic–Early Cretaceous time scales Special Publications, 373, first published on November
and oceanic magnetic anomaly block models. In: 15, 2012, doi: 10.1144/SP373.5.
Berggren, W. A. et al. (eds) Geochronology, Time- Firth, J. V., Eldrett, J. S., Harding, I. C., Coxall, H.
scales, and Stratigraphic Correlation. Society for K. & Wade, B. S. 2012. Integrated biomagnetochro-
Sedimentary Geolists, Tulsa, OK, 51–63. nology for the Palaeogene of ODP Hole 647A: impli-
Channell, J. E. T., Mazaud, A., Sullivan, P., Turner, cations for correlating palaeoceanographic events
S. & Raymo, M. E. 2002. Geomagnetic excursions and from high to low latitudes. In: Jovane, L., Herrero-
paleointensities in the 0.9– 2.15 Ma interval of the Bervera, E., Hinnov, L. A. & Housen, B. A. (eds)
Matuyama Chron at ODP Site 983 and 984 (Iceland Magnetic Methods and the Timing of Geological Pro-
Basin). Journal of Geophysical Research, 107, doi: cesses. Geological Society, London, Special Publi-
10.1029/2001JB000491. cations, 373, first published on October 1, 2012, doi:
Coccioni, R., Sideri, M. et al. 2012. Integrated strati- 10.1144/SP373.9.
graphy (magneto-, bio- and chronostratigraphy) and Florindo, F., De Michelis, P., Piersanti, A. & Boschi,
geochronology of the Palaeogene pelagic succession E. 2005. Could the Mw ¼ 9.3 Sumatra Earthquake
of the Umbria–Marche Basin (central Italy). In: Trigger a Geomagnetic Jerk? EOS, Transactions of
Jovane, L., Herrero-Bervera, E., Hinnov, L. A. the American Geophysical Union, 86, 123–124.
& Housen, B. A. (eds) Magnetic Methods and the Franco, D. R. & Hinnov, L. A. 2012. Anisotropy of
Timing of Geological Processes. Geological Society, magnetic susceptibility and sedimentary cycle data
London, Special Publications, 373, first published on from Permo-Carboniferous rhythmites (Paraná Basin,
November 16, 2012, doi: 10.1144/SP373.4. Brazil): a multiple proxy record of astronomical and mil-
Collinson, A. W. 1983. Methods in Rock Magnetism and lennial scale palaeoclimate change in a glacial setting.
Paleomagnetism. Techniques and Instrumentation. In: Jovane, L., Herrero-Bervera, E., Hinnov, L. A.
Chapman and Hall, New York. & Housen, B. A. (eds) Magnetic Methods and the
Cox, A., Doell, R. R. & Dalrymple, G. B. 1963. Geo- Timing of Geological Processes. Geological Society,
magnetic polarity epochs and Pleistocene geochrono- London, Special Publications, 373, first published on
metry. Nature, 198, 1049–1051. November 6, 2012, doi: 10.1144/SP373.11.Downloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022 10 L. JOVANE ET AL. Gee, J. S. & Kent, D. V. 2007. Source of oceanic magnetic & Housen, B. A. (eds) Magnetic Methods and the anomalies and the geomagnetic polarity time scale. Timing of Geological Processes. Geological Society, Geomagnetism. In: Kono, M. (ed.) Treatise on Geo- London, Special Publications, 373, first published on physics. Elsevier, Amsterdam, 5, 455–507. December 7, 2012, doi: 10.1144/SP373.12. Glatzmaier, G. A. & Roberts, P. H. 1995. A three- Herrero-Bervara, E. & Jovane, A. In press. On the dimensional convective dynamo solution with rotating palaeomagnetic and rock magnetic constraints regard- and finitely conducting inner core and mantle. Physics ing the age of IODP 325 Hole M0058A. In: Jovane, L., of the Earth and Planetary Interiors, 91, 63– 75. Herrero-Bervera, E., Hinnov, L. A. & Housen, B. Goldstein, A. G. 1980. Magnetic susceptibility aniso- A. (eds) Magnetic Methods and the Timing of Geo- tropy of mylonites from the Lake Char mylonite logical Processes. Geological Society, London, Spe- zone, southeastern New England. Tectonophysics, 66, cial Publications, 373, http://dx.doi.org/10.1144/ 197– 211. SP373.19 Gubbins, D. & Bloxham, J. 1985. Geomagnetic field Hinnov, L. A. & Hilgen, F. 2012. Chapter 4: cyclostrati- analysis – III. Magnetic fields on the core –mantle graphy and astrochronology. In: Gradstein, F. M., boundary. Geophysical Journal of the Royal Astronom- Ogg, J. G., Schmitz, M. D. & Ogg, G. M. (eds) The Geo- ical Society, 80, 695– 713. logic Time Scale 2012. Elsevier, Amsterdam, 63–83. Gubbins, D. & Bloxham, J. 1987. Morphology of the geo- Hinnov, L., Kodama, K. P., Anastasio, D. J., Elrick, M. magnetic field and implications for the geodynamo. & Latta, D. K. In press. Global Milankovitch cycles Nature, 325, 509–511. recorded in rock magnetism of the shallow marine Guidry, E. P., Richter, C. et al. 2012. Oligocene– lower Cretaceous Cupido Formation, northeastern Miocene magnetostratigraphy of deep-sea sediments Mexico. In: Jovane, L., Herrero-Bervera, E., from the equatorial Pacific (IODP Site U1333). In: Hinnov, L. A. & Housen, B. A. (eds) Magnetic Jovane, L., Herrero-Bervera, E., Hinnov, L. A. Methods and the Timing of Geological Processes. Geo- & Housen, B. A. (eds) Magnetic Methods and logical Society, London, Special Publications, 373, the Timing of Geological Processes. Geological http://dx.doi.org/10.1144/SP373.20 Society, London, Special Publications, 373, first pub- Housen, B. A. & Moskowitz, B. M. 2006. Depth distribu- lished on August 17, 2012, doi: 10.1144/SP373.7. tion of magnetofossils in near surface sediments from Gunderson, K. L., Kodama, K. P., Anastasio, D. J. & the Blake/Bahama Outer Ridge, western North Atlantic Pazzaglia, F. J. 2012. Rock-magnetic cyclostratigra- Ocean, determined by low-temperature magnetism. phy for the Late Pliocene–Early Pleistocene Stirone Journal of Geophysical Research, 111, G01005. section, Northern Apennine mountain front, Italy. In: Hrouda, F. 1982. Magnetic anisotropy of rocks and its Jovane, L., Herrero-Bervera, E., Hinnov, L. A. application in geology and geophysics. Geophysical & Housen, B. A. (eds) Magnetic Methods and the Surveys, 5, 37– 82. Timing of Geological Processes. Geological Society, Huestis, S. P. & Acton, G. D. 1997. On the construction London, Special Publications, 373, first published on of geomagnetic timescales from nonprejudicial treat- August 14, 2012, doi: 10.1144/SP373.8. ment of magnetic anomaly data from multiple ridges. Guyodo, Y. & Valet, J.-P. 1999. Global changes in inten- Geophysical Journal International, 129, 176 –182. sity of the Earth’s magnetic field during the past Hulot, G., Eymin, C., Langlais, B., Mandea, M. & 800 kyr. Nature, 399, 249– 252. Olsen, N. 2002. Small-scale structure of the geody- Haberzettl, T., St-Onge, G., Behling, H. & Kirleis, namo inferred from Oersted and Magsat satellite W. 2012. Evaluating Late Holocene radiocarbon-based data. Nature, 416, 620–623. chronologies by matching palaeomagnetic secular Irving, E. 1956. Palaeomagnetic and palaeoclimatic variations to geomagnetic field models: an example aspects of polar wandering. Geofisica pura e applicata, from Lake Kalimpaa (Sulawesi, Indonesia). In: 33, 23–41. Jovane, L., Herrero-Bervera, E., Hinnov, L. A. Irving, E. 1963. Paleomagnetism of the Narrabeen Choco- & Housen, B. A. (eds) Magnetic Methods and the late Shales and the Tasmanian Dolerite. Journal of Timing of Geological Processes. Geological Society, Geophysical Research, 68, 2283– 2287. London, Special Publications, 373, first published on Jackson, A., Jonkers, A. R. T. & Walker, M. R. 2000. August 14, 2012, doi: 10.1144/SP373.10. Four centuries of geomagnetic secular variation from Handschumacher, D. W., Sager, W. W., Hilde, historical records. Philosophical Transactions of the T. W. C. & Bracey, D. R. 1988. Pre-Cretaceous tec- Royal Society of London Series A, 358, 957– 990. tonic evolution of the Pacific plate and extension of Jacobs, J. A. 1984. Reversals of the Earth’s Magnetic field. the geomagnetic polarity reversal time scale with Adam Hilger, Bristol. implications for the origin of the Jurassic ‘Quiet Jovane, L., Acton, G., Florindo, F. & Verosub, K. L. Zone’. Tectonophysics, 155, 365– 380. 2008. Geomagnetic field behavior at high latitudes Heirtzler, J. R., Dickson, G. O., Herron, E. M., from a paleomagnetic record from Eltanin Core 27– Pitman, W. C. III. & Le Pichon, X. 1968. Marine 21 in the Ross Sea Sector, Antarctica. Earth and Plane- Magnetic Anomalies, geomagnetic field reversals, tary Science Letters, 263, 435–443. and motions of the ocean floor and continents. Jovane, L., Florindo, F., Bazylinski, D. A. & Lins, U. Journal of Geophysical Research, 73, 2119–2136. 2012. Prismatic magnetite magnetosomes from culti- Herrero-Bervera, E. & Cañón-Tapia, E. 2012. On the vated Magnetovibrio blakemorei strain MV-1: a directional geomagnetic signature of the Pringle Falls magnetic fingerprint in marine sediments? Environ- excursion recorded at Pringle Falls, Oregon, USA. In: mental Microbiology Reports, 4, 664–668, doi: Jovane, L., Herrero-Bervera, E., Hinnov, L. A. 10.1111/1758- 2229.12000
Downloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022
MAGNETOSTRATIGRAPHY: ONLY A DATING TOOL? 11
Jovane, L., Savian, J. et al. 2013. Integrated magneto- Lowrie, W., Alverez, W., Napoleone, G., Perch-
biostratigraphy of the middle Eocene-lower Oligocene Nielson, K., Premoli Silva, I. & Toumarine, M.
interval from the Monte Cagnero section, central Italy. 1982. Paleogene magnetic stratigraphy in Umbrian
In: Jovane, L., Herrero-Bervera, E., Hinnov, L. A. pelagic carbonate rocks: the Contessa sections, Gubbio.
& Housen, B. A. (eds) Magnetic Methods and the Geological Society of America Bulletin, 93, 414–432.
Timing of Geological Processes. Geological Society, Lund, S., Stoner, J. S., Channell, J. E. T. & Acton, G.
London, Special Publications, 373, first published on 2006. A summary of Brunhes paleomagnetic field
March 25, 2013, doi: 10.1144/SP373.13. variability recorded in Ocean Drilling Program cores.
Kearey, P., Klepeis, K. A. & Vine, F. J. 2009. Global Physics of the Earth and Planetary Interiors, 156,
Tectonics. 3rd edn. Wiley, Chichester. 194– 204.
King, J. & Channell, J. E. T. 1991. Sedimentary magnet- Malinverno, A., Hildebrandt, J., Tominaga, M. &
ism, environmental magnetism, and magnetostratigra- Channell, J. E. T. 2012. M-sequence geomagnetic
phy. U.S. National Report to the International Union polarity time scale (MHTC12) that steadies global
of Geodesy and Geophysics. Reviews of Geophysics, spreading rates and incorporates astrochronology con-
Supplement, 29, 358–370. straints. Journal of Geophysical Research, 117, B06104.
King, J. W., Banerjee, S. K. & Marvin, J. 1983. A new Mandea, M., Bellanger, E. & Le Moul, J. L. 2000. A
rock-magnetic approach to selecting sediments for geomagnetic jerk for the end of the 20th century?
geomagnetic paleointensity studies: application to Earth and Planetary Science Letters, 183, 369–373.
paleointensity for the last 4000 years. Journal of Geo- Matuyama, M. 1926. On the direction of magnetization of
physical Research, 88, 5911– 5921. basalt in Japan. Proceedings of the Imperial Academy,
Kirschvink, J. L. 1980. The least-squares line and plane 5, 203– 205.
and the analysis of palaeomagnetic data. Geophysical McCaffrey, R. 2005. Block kinematics of the Pacific–
Journal of the Royal Astronomical Society, 62, North America plate boundary in the southwestern US
699–710. from inversion of GPS, seismological, and geologic
Kodama, K. 2012. Paleomagnetism of Sedimentary Rocks: data. Journal of Geophysical Research, 110, B07401.
Process and Interpretation. Wiley-Blackwell, Oxford. McElhinny, M. & McFadden, P. 2000. Paleomagnet-
Kuang, , W. & Bloxham, J. 1997. An Earth-like numeri- ism: Continents and Oceans. International Geophysics
cal dynamo model. Nature, 389, 371–374. Series, 73, Academic Press, San Diego.
LaBreque, J. L., Kent, D. V. & Cande, S. C. 1977. Muller, R. A. & Morris, D. E. 1986. Geomagnetic rever-
Revised magnetic polarity time scale for Late Cretac- sals from impacts on the Earth. Geophysical Research
eous and Cenozoic time. Geology, 5, 330– 335. Letters, 13, 1177–1180.
Laj, C. & Channell, J. E. T. 2007. Geomagnetic excur- Ogg, J. G. 2012. Chapter 5: geomagnetic polarity time
sions. In: Kono, M. (ed.) Treatise in Geophysics: scale. In: Gradstein, F. M., Ogg, J. G., Schmitz,
Volume 5, Geomagnetism. Elservier, Amsterdam, M. D. & Ogg, G. M. (eds) The Geologic Time Scale
Chapter 10, 373– 416. 2012. Elsevier, Amsterdam, 85– 113.
Lanci, L. & Lowrie, W. 1997. Magnetostratigraphic evi- Olson, P. & Aurnou, P. 1999. A polar vortex in the
dence that ‘tiny wiggles’ in the oceanic magnetic Earth’s core. Nature, 402, 170 –173.
anomaliy record represent geomagnetic paleointensity Olson, P. L., Coe, R. S., Driscoll, P. E., Glatzmaier, G.
variations. Earth and Planetary Science Letters, 148, A. & Roberts, P. H. 2010. Geodynamo reversal fre-
581–592. quency and heterogeneous core-mantle boundary heat
Larrasoaña, J. C., Roberts, A. P., Rohling, E. J., flow. Physics of the Earth and Planetary Interiors,
Winklhofer, M. & Wehausen, R. 2003. Three 180, 66–79.
million years of monsoon variability over the northern Opdyke, N. D. 1972. Palaeomagnetism of deep-sea cores.
Sahara. Climatic Dynamics, 21, 689–698. Reviews of Geophysics and Space Physics, 10,
Laskar, J., Robutel, P., Joutel, J., Gastineau, M., 213– 249.
Correia, A. C. M. & Levrard, B. 2004. A numerical Opdyke, N. D. & Channell, J. E. T. 1996. Magnetic Stra-
solution for the insolation quantities of the Earth. tigraphy. Academic Press, San Diego, CA.
Astronomy and Astrophysics, 428, 261–285. Petersen, N., von Dobeneck, T. & Vali, H. 1986. Fossil
Laskar, J., Fienga, A., Gastineau, M. & Manche, H. bacterial magnetite in deep-sea sediments from the
2011. A new orbital solution for the long-term motion South Atlantic Ocean. Nature, 320, 611–615.
of the Earth. Astronomy and Astrophysics., 532, A89. Roberts, A. P., Florindo, F. et al. 2011. Magnetotactic
Liu, Z., Zhao, X., Chengshan, W., Shun, L. & Haishen, bacterial abundance in pelagic marine environments is
Y. 2003. Magnetostratigraphy of Tertiary sediments limited by organic carbon flux and availability of dis-
from the Hoh Xil Basin: implications for the Cenozoic solved iron. Earth and Planetary Science Letters,
tectonic history of the Tibetan Plateau. Geophysical 310, 441–452.
Journal International, 154, 233–252. Roberts, A. P., Chang, L., Heslop, D., Florindo, F. &
Liu, Q. S., Roberts, A. P., Torrent, J. & Horng, C. S. Larrasoaña, J. C. 2012. Searching for single
2007. What do the HIRM and S-ratio really measure domain magnetite in the ‘pseudo-single-domain’ sedi-
in environmental magnetism? Geochemistry Geophy- mentary haystack: implications of biogenic magnetite
sics Geosystems, 8, Q09011. preservation for sediment magnetism and relative
Liu, Q. S., Roberts, A. P., Larrasoaña, J. C., Banerjee, paleointensity determinations. Journal of Geophysical
S. K., Guyodo, Y., Tauxe, L. & Oldfield, F. 2013. Research, 117, B08104.
Environmental Magnetism: principles and appli- Sager, W. W., Weiss, M. A., Tivey, M. A. & Johnson, H. P.
cations. Reviews of Geophysics, 50, RG4002. 1998. Geomagnetic polarity reversal model of deep-towDownloaded from http://sp.lyellcollection.org/ by guest on February 13, 2022 12 L. JOVANE ET AL. profiles from the Pacific Jurassic ‘Quiet Zone’. Journal Vasiliev, I., Franke, C., Meeldijk, J. D., Dekkers, M. J., of Geophysical Research, 103, 5269–5286. Langereis, C. G. & Krijgsman, W. 2008. Putative Savian, J., Jovane, L., Bohaty, S. & Wilson, P. 2013. greigite magnetofossils from the Piocene epoch. Middle Eocene to early Oligocene magnetostratigra- Nature Geoscience, 1, 782–786. phy of ODP Hole 711A (Leg 115), western equatorial Verosub, K. L. 1977. Paleomagnetic record of Clear Lake, Indian Ocean. In: Jovane, L., Herrero-Bervera, E., California. Earth and Planetary Science Letters, 36, Hinnov, L. A. & Housen, B. A. (eds) Magnetic 219–230. Methods and the Timing of Geological Processes. Geo- Verosub, K. L. & Roberts, A. P. 1995. Environmental logical Society, London, Special Publications, 373, magnetism: past, present, and future. Journal of Geo- first published on March 25, 2013, doi: 10.1144/ physical Research, 100, 2175–2192. SP373.16. Vine, F. J. & Matthews, D. H. 1963. Magnetic anomalies Singer, B. S., Relle, M. R., Hoffman, K. A., Battle, A., over oceanic ridges. Nature, 199, 947– 949. Guillou, H., Laj, C. & Carracedo, J. C. 2002. Ar/ Wardinski, I. & Holme, R. 2006. A time-dependent Ar ages of transitionally magnetized lavas on La model of the Earth’s magnetic field and its secular Palma, Canary Islands, and the Geomagnetic Instabil- variation for the period 1980– 2000. Journal of Geo- ity Timescale. Journal of Geophysical Research, physical Research, 111, B12101, doi: 10.1029/ 107, 2307. 2006JB004401. Stacey, F. D. 1960. Magnetic anisotropy of igneous rocks. Yamazaki, T. 2008. Magnetostatic inter actions in Journal of Geophysical Research, 65, 2429–2442. deep-sea sediments inferred from first-order reversal Suganuma, Y., Okuno, J., Heslop, D., Roberts, A. P., curve diagrams: implications for relative paleointen- Yamazaki, T. & Yokoyama, Y. 2011. Post-depositional sity normalization. Geochemistry, Geophysics, Geo- remanent magnetization lock-in for marine sediments systems, 9, Q02005. deduced from 10Be and paleomagnetic records through Yamazaki, T. 2009. Environmental magnetism of Pleisto- the Matuyama-Brunhes boundary. Earth and Planetary cene sediments in the North Pacific and Ontong-Java Science Letters, 311, 39–52, 2011. Plateau: temporal variations of detrital and biogenic Tan, X. & Kodama, K. P. 2002. Magnetic anisotropy components. Geochemistry, Geophysics, Geosystems, and paleomagnetic inclination shallowing in red 10, Q07Z04. beds: evidence from the Mississippian Mauch Chunk Yan, M., Van Der Voo, R., Fang, X.-M. & Song, C. Formation, Pennsylvania. Journal of Geophysical 2012a. Magnetostratigraphy, fence diagrams and Research, 107, 2311. basin analysis. In: Jovane, L., Herrero-Bervera, Tauxe, L. 2010. Essentials of Paleomagnetism. University E., Hinnov, L. A. & Housen, B. A. (eds) Magnetic of California, Berkeley. Methods and the Timing of Geological Processes. Tauxe, L. & Yamazaki, T. 2007. Paleointensities. In: Geological Society, London, Special Publications, Schubert, G. (ed.) Treatise on Geophysics. Elsevier, 373, first published on August 17, 2012, doi: Amsterdam. 10.1144/SP373.3 Tauxe, L., Steindorf, J. L. & Harris, A. J. 2006. Deposi- Yan, M., Fang, X, Van Der Voo, R., Song, C. & Li, J. tional remanent magnetization: toward an improved 2012b. Neogene rotations in the Jiuquan Basin, Hexi theoretical and experimental foundation. Earth and Corridor, China. In: Jovane, L., Herrero-Bervera, Planetary Science Letters, 244, 515–529. E., Hinnov, L. A. & Housen, B. A. (eds) Magnetic Titus, S. J., Crump, S., McGuire, Z., Horsman, E. & Methods and the Timing of Geological Processes. Geo- Housen, B. 2011. Using vertical axis rotations to charac- logical Society, London, Special Publications, 373, terize off-fault deformation across the San Andreas fault first published on November 16, 2012, doi: 10.1144/ system, central California. Geology, 39, 711–714. SP373.6. Tivey, M. A., Sager, W. W., Lee, S.-M. & Tominaga, M. Zhao, X., Ladner, B., Roessig, K., Wise, S. & Urqu- 2006. Origin of the Pacific Jurassic quiet zone. hart, E. 2001. Magnetic stratigraphy and biostratigra- Geology, 34, 789– 792. phy of cenozoic sediments recovered from the Iberian Valet, J.-P. & Meynadier, L. 1998. A comparison of Abyssal Plain. In: Beslier, M.-O., Whitmarsh, R. B., different techniques for relative paleointensity. Geo- Wallace, P. J. & Girardeau, J. (eds) Proceedings of physical Research Letters, 25, 89– 92. the Ocean Drilling Program, Scientific Results, 172, Valet, J.-P. & Herrero-Bervera, E. 2000. Paleointen- Ocean Drilling Program, Texas A & M University, sity experiments using alternating field demagnetiza- College Station, TX, 1– 73 [CD-ROM]. tion. Earth and Planetary Science Letters, 177, 43– 58. Zhao, X., Oda, H. et al. 2013. Magnetostratigraphic Valet, J. P., Meynadier, L. & Guyodo, Y. 2005. Geo- results from sedimentary rocks of IODP’s Nankai magnetic field strength and reversal rate over the past Trough Seismogenic Zone Experiment (NanTro- 2 Million years. Nature, 435, 802–805. SEIZE) Expedition 322. In: Jovane, L., Herrero- Valet, J. P., Plenier, G. & Herrero-Bervera, E. 2008. Bervera, E., Hinnov, L. A. & Housen, B. A. (eds) Geomagnetic excursions reflect an aborted polarity Magnetic Methods and the Timing of Geological Pro- state. Earth and Planetary Science Letters, 274, cesses. Geological Society, London, Special Publi- 472– 478. cations, 373, first published on March 25, 2013, doi: Van der Voo, R. 1988. Paleozoic paleogeography of 10.1144/SP373.14. North America, Gondwana, and intervening displaced Zijderveld, J. D. A. 1967. A.C. demagnetization of rocks. terranes: comparisons of paleomagnetism with paleo- In: Collison, D. W., Creer, K. M. & Runcorn, S. K. climatology and biogeographical patterns. Geological (eds) Methods in Palaeomagnetism. Elsevier, Amster- Society of America Bulletin, 100, 311–324. dam, 256–286.
You can also read
