RT Journal Article
T1 Datación paleomagnética de la parte sur del dique de Messejana-Plasencia
A1 Palencia Ortas, Alicia
A1 Osete López, María Luisa
A1 Vegas Martínez, Ramón
A1 Villasante Marcos, Víctor
A1 Silva, Pedro F.
A1 Fonseca, P.E.
A1 Miranda Pantoja, José Miguel
AB A Paleomagnetic investigation of 11 sites across the southern part of Messejana-Plasencia dike has been carried out. The magnetic behaviour o f pilot samples indicates that thermal demagnetisation is more effective than alternating field cleaning (AF) in isolating the Characteristic Remanent Magnetisation (ChRM). Therefore thermal demagnetisation was systematically used with the remaining samples. The ChRM is well grouped. Most sites exhibit normal polarities with the exception of two sites, where samples with reversed polarities have been observed. The paleomagnetic pole derived from the sites is well defined, with values of Plat=72.5, Plong=243.7 and Al);=6.0. This coincides with the pole calculated in a previous investigation (Schott et at. 1981) o f the dike. It is also in agreement with Toarcian poles from the Iberian Range (Osete et al. 2000) and statistically different from the Oxfordian Pole obtained in the same region. Previous radiometric studies suggested that the age o f dike intrusion is 160-200Ma. Paleomagnetic data indicates that the age o f intrusion can be constrained between 180-200Ma.
PB Sociedad Geológica de España.
SN 1576-5172
YR 2000
FD 2000
LK https://hdl.handle.net/20.500.14352/57952
UL https://hdl.handle.net/20.500.14352/57952
LA spa
NO (DGICYT)
DS Docta Complutense
RD 8 may 2024