Open AccessA Holocene–Late Pleistocene geomagnetic inclination record from Grandfather Lake, SW Alaska
Author(s) -
Geiss C. E.,
Banerjee S. K.
Publication year - 2003
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1046/j.1365-246x.2003.01921.x
Subject(s) - geology , radiocarbon dating , earth's magnetic field , holocene , pleistocene , paleomagnetism , paleontology , quaternary , oceanography , magnetic field , physics , quantum mechanics
SUMMARY Our study of lake sediments from Grandfather Lake in SW Alaska (N59.8181°, W158.5597°) yields the first geomagnetic inclination record for Alaska that spans the entire Holocene. The record is based on three overlapping sets of piston cores and is well dated by seven AMS radiocarbon dates. Its magnetic component consists of PSD (5–15 μm) magnetite that occurs in concentrations ranging from 10 to 1000 ppm. Some samples may also contain titanomagnetite (TM30) as a minor component. Variations in the concentration of magnetic minerals are caused by changes in sediment source and organic productivity. The magnetic inclination record shows several features between present and 15 ka BP, which shed light on the short‐term behaviour of the geomagnetic field at high latitudes and can be used for site correlations. A distinct drop in inclination near 12 ka BP is a record of a possible local magnetic excursion.