Carvallo, C. et al. (2013): Palaeointensity determinations and rock magnetic properties on basalts from Shatsky Rise; new evidence for a Mesozoic dipole low
Leg/Site/Hole:
Related Expeditions:
IODP 324
Identifier:
ID:
2013-041271
Type:
georefid
ID:
10.1093/gji/ggs100
Type:
doi
Creator:
Name:
Carvallo, C.
Affiliation:
Universite Pierre et Marie Curie, Institut de Mineralogie et de Physique des Milieux Condensee, Paris, France
Role:
author
Name:
Camps, Pierre
Affiliation:
CNRS, France
Role:
author
Name:
Ooga, M.
Affiliation:
Doshisha University, Japan
Role:
author
Name:
Fanjat, G.
Affiliation:
Texas A&M University, United States
Role:
author
Name:
Sager, W. W.
Affiliation:
Role:
author
Identification:
Title:
Palaeointensity determinations and rock magnetic properties on basalts from Shatsky Rise; new evidence for a Mesozoic dipole low
Year:
2013
Source:
Geophysical Journal International
Publisher:
Oxford University Press on behalf of The Royal Astronomical Society, the Deutsche Geophysikalische Gesellschaft and the European Geophysical Society, International
Volume:
192
Issue:
3
Pages:
986-999
Abstract:
IODP Expedition 324 cored igneous rocks from Shatsky Rise, an oceanic plateau in the northwest Pacific Ocean that formed mainly during late Jurassic and Early Cretaceous times. We selected 60 samples from 3 different holes for Thellier-Thellier paleointensity determinations. Induced and remanent magnetization curves measured at low- and high-temperature suggest a diverse and complex magnetic mineralogy, with large variations in Ti content and oxidation state. Hysteresis and FORC measurements show that most samples contain single-domain magnetic grains. After carrying out the paleointensity determinations, only 9 samples satisfied all reliability criteria. These gave paleointensity values between 16.5 and 21.5 mu T, which correspond to average VDM values of (4.9 + or - 0.2) X 1022 Am2 for an estimated age of 140-142 Ma. This value is lower than that for the recent field, which agrees with the hypothesis of a Mesozoic Dipole Low.
Language:
English
Genre:
Serial
Rights:
URL:
Coverage: Geographic coordinates: North:38.0000 West:157.0000 East:
163.0000 South:32.0000
Keywords: Stratigraphy; Solid-earth geophysics; basalts; Cretaceous; demagnetization; Expedition 324; igneous rocks; Integrated Ocean Drilling Program; IODP Site U1346; IODP Site U1347; IODP Site U1348; IODP Site U1349; IODP Site U1350; Jurassic; Lower Cretaceous; magnetic properties; magnetization; Mesozoic; North Pacific; Northwest Pacific; Pacific Ocean; paleointensity; paleomagnetism; remanent magnetization; sampling; Shatsky Rise; Thellier method; volcanic rocks; West Pacific;
.