Search

The palaeomagnetic dating and evolution of the Faroe Islands are discussed in the context of new density and rock magnetic results from the deepened Lopra-1/1A well. The reversal chronology of thec. 6½ km thick basalt succession is also described. The polarity record of the Faroe Islands may now be correlated in detail with the Geomagnetic Polarity Time Scale. The lowermost (hidden) part of thelower basalt formation correlates with Chron C26r (Selandian age), the top (exposed) part of the lower basalt formation correlates with Chrons C26n, C25r and C25n (Selandian and Thanetian age)and the middle and upper basalt formations correlate with Chron C24n.3r (Ypresian). Inclinations indicate a far-sided position of the palaeomagnetic poles, which is characteristic of results from mostPalaeogene volcanics from the northern North Atlantic region. The density, magnetic susceptibility and magnetic remanence of 20 specimens from one solid core (1½ m in length) and 26 sidewall cores from the well between –2219 and –3531 m below sea level (b.s.l.) suggest that the volcanic materials can be divided into two characteristic groups: solid unaltered basalts and altered basalts and tuffs. The magnetic properties are typically log-normally distributed and the carriers of remanence are Ti-poor Ti-magnetites with Curie temperatures close to 580°C. The inclination of the 1½ m core at 2380 m b.s.l. is dominantly negative (two plugs at the very top of the core do show normal polarity, but they are likely to be misoriented as all specimens appear to be from one flow). Magnetic logging (magnetic susceptibility and field intensity) down to 3515 m b.s.l. was made in Lopra-1/1A together with other geophysical logs but did not yield conclusive inclination data.

This publication discusses scientific results following the deepening of the Lopra-1 borehole in Faroe Islands. Work on the well started on July 13, 1996 and ended on November 3, 1996, increasing its depth to 3,565 meters. A total of 19 oil companies were involved in the project, including Amerada Hess Ltd., BHP Petroleum Inc. and Chevron Europe Ltd.

In the Lithuania, a palaeomagnetic study of Upper Pleistocene and Late Glacial sediments at five sections has been carried out. The palaeomagnetic study of the varved clays in the Maskauka, Did&zbrave;iasalis and Girininkai sections cover the time interval since 18,000 to 14,000 BP and Man&cbrave;iagirė section covers the time interval since 12,700 to 11,630 BE The palaeomagnetic research of the Merkinė (= Eemian) Interglacial sediments (Netiesos section) cover the time interval since 112.0±25 to 101.5 ± 11.5 ka BE The declination (D), inclination (I) and intensity (J) of the natural remanent magnetization of glaciolacustrine clays (Maskauka, Did&zbrave;asalis and Girininkai sections), as well as Merkinė (=Eemian) Interglacial deposits (Netiesos section) and interstadial sediments (Man&zbrave;iagirė section) were measured. The result of these studies is presented in diagrams. The study reveals that considerable palaeomagnetic information can be obtained from the varved clays. [ABSTRACT FROM AUTHOR]