Application of the pseudo-Thellier technique to a paleomagnetic record from lake El Trébol (Patagonia, Argentina)

Abstract

The pseudo–Thellier technique was applied to obtain relative paleointensity determinations using a sediment core from Lake El Trébol (Patagonia, Argentina).
Measurements of intensity of natural remanent magnetization left (NRM_left) after AF demagnetization versus intensity of anhysteric remanent magnetization gained (ARM _gained) at the same peak were carried out on a set of samples. Two versions of a jackknife resampling scheme were used to get error estimates on the paleointensity.
The pseudo–Thellier paleointensity records were compared with the authors previous results where the remanent magnetization at 20mT (NRM_20mT) has been normalized using the anhysteric remanent magnetization at 20mT (ARM_20mT), the saturation of the isothermal remanent magnetization at 20mT (SIRM_20mT) and the low field magnetic susceptibility (k) (Gogorza et al., 2006). The pseudo–Thellier record shows a reasonable agreement with the standard method of normalization (NRM_20mT/ ARM_20mT).