SYNOPSIS OF PALEOMAGNETIC STUDIES IN THE KAPUSKASING STRUCTURAL ZONE

This paper summarizes results from paleomagnetic studies sponsored by Lithoprobe an the Kapuskasing structural zone (KSZ). Data from Archean rocks outside the KSZ indicate that the Wawa Subprovince has not been significantly rotated or translated (<5 degrees) relative to the Abit ibi Subprovince. Results from the granulites and amphibolites indicate that the KSZ underwent several kilometres of uplift at ca. 2.51 Ga an d then 10 +/- 5 degrees west-northwest tilt with several kilometres of further uplift between 2.04 and 1.88 Ga from thrust faulting on the I vanhoe Lake fault zone. Localized chemical remagnetization occurred at 1.1 Ga along the west side of the Shawmere anorthosite. Paleomagnetic data from the 2.45 Ga Matachewan diabase dike swarm indicate that it was emplaced within one reversed to normal polarity interval of less t han 5 Ma, Their polarity pattern indicates major north-trending faults with several kilometres of dip-slip displacement. Their remanence con firms that the Superior Province was deformed around the KSZ into an o roclinal flexure with 40 degrees changes in trend between 2.04 and 1.8 8 Ga. Results from eight 1.1 Ga alkali syenite-carbonatite complexes s how that the KSZ and adjacent subprovinces have undergone only minor u plift (< 6 +/- 2 km) since emplacement. Also, these data refine the ra diometric ages of some complexes, demonstrate that the use of superchr ons to correlate Keweenawan units in the Midcontinental Rift is unsoun d, and show that Keweenawan magnetic field was symmetrical. Many speci fic conclusions that relate to a given unit or limited area were drawn in the KSZ paleomagnetic studies.