Open AccessPalaeomagnetic Stratigraphy of Tertiary Lavas from Northern Ireland
Author(s) -
Wilson R. L.
Publication year - 1970
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1970.tb06744.x
Subject(s) - lava , geology , stratigraphy , basalt , paleontology , paleomagnetism , group (periodic table) , magnetic declination , volcano , geophysics , earth's magnetic field , tectonics , magnetic field , chemistry , physics , organic chemistry , quantum mechanics
Summary Three lava profiles, sampled at 1.3 km and 2.3 km spacings, overlap stratigraphically as proven by two geological marker horizons. Groups of several successive lavas often have remarkably coherent directions of magnetization. Further, on three occasions, a group of lavas in one profile correlates palaeomagnetically with a group in another profile, and these correlations agree very well with the geological marker horizons. A lava‐mean α 95 of 3.1° makes possible palaeomagnetic stratigraphy based on secular variation, apparently within one polarity epoch (reversed). Since many lavas seem to have recorded virtually the same magnetic field, 54 distinct lavas contribute only 25 distinct spot values of the ancient field, from which we deduce a mean pole position at 69.6° N and 162.9° E, with P = 5° and M = 7°.