Propiedades magnéticas de los sedimentos recientes de los lagos Ausente e Isoba (Cordillera Cantábrica, norte de España) como trazadores de cambios ambientales e influencia antrópica
- V. Villasante-Marcos 1
- R. González 2
- F. Martín 2
- M. Morellón 2
- J. Gardoki 2
- 1 Observatorio Geofísico Central, Instituto Geográfico Nacional, Real Observatorio de Madrid
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2
Universidad Complutense de Madrid
info
ISSN: 1576-5172
Year of publication: 2021
Issue Title: X Congreso Geológico de España
Issue: 18
Pages: 1040
Type: Article
More publications in: Geotemas (Madrid)
Abstract
Two cores of recent sediments from Lake Ausente (altitude: ca. 1750 masl) and Lake Isoba (altitude: ca. 1400 masl), both in the Cantabrian Range (northern Spain), have been investigated for their rock-magnetic properties. We have measured mag- netic susceptibility of whole cores (core-through and surface sensors), as well as magnetic parameters of discrete subsamples recovered from the cores at 1 cm stratigraphic resolution (magnetic susceptibility, hysteresis and remanence cycles, thermo- magnetic cycles). The results of this magnetic characterization have been correlated with organic content and geochemistry data, both major element and heavy metal abundances. An age model has been obtained for the cores based on 210 Pb and 137 Cs precise dating. All these data allow the reconstruction of the environmental changes, being natural or anthropogenic, recorded in these lacustrine sediments during the last four centuries in Isoba and the last two millennia in Ausente. The com- parison between both lakes, due to their difference in altitude, allows also to infer some information about differences in the type and intensity of the anthropic impacts experimented by each lake.