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Chamosite-hematite type oolitic ironstone is distributed in the Cretaceous-Tertiary (K-T) boundary zone of the Hazara area, Lesser Himalayan thrust zone, in the northwestern margin of the Indo-Pakistani subcontinent. A total of 52 oriented samples were collected from 6 beds in two open pit mines, Nathia Gali and Bagnotar. Ferromagnetic properties of the oolitic ironstone are dominated by fine-grained hematite that possesses a characteristic remanent magnetization (ChRM). The ChRM is a chemical remanent magnetization (CRM) acquired by the hematite which formed from Fe-rich initial materials (iron hydroxides) during early diagenesis of the ironstone bed. The direction of the remanent magnetization indicates that the magnetization was acquired in an equatorial region (average inclination = 2°, paleolatitude = 1°N), which is consistent with the paleoposition of the Indian subcontinent during early Paleocene time, as estimated by previous data. The initial Fe-rich sediments were deposited under anoxic conditions, probably in a non-marine or brackish environment. During early diagenesis, after development of oolitic textures, the paleoenvironment became arid, where the CRM was acquired through the conversion of amorphous hydroxides or goethite to fine-grained hematite. The paleomagnetic results reveal complicated local rotational movements of oolitic ironstone blocks about vertical axes, which might be a result of intense thrusting within the terrane after early Tertiary collision between India and Asia.

The Utror Volcanic Formation forms a NE-SW belt with in Kohistan island arc, which lies between the Indian and Eurasian continents in the western Himalayas of northern Pakistan. The Utror Volcanic Formation formed during Late Paleocene, when Kohistan existed as an Andean-type arc on the southern margin of Eurasia. Five to ten block samples were collected from 17 sites of the formation for paleomagnetic studies. Magnetic minerals that serve as remanent carriers are maghemite, magnetite, hematite and titanohematite. Magnetite, hematite, and titanohematite carry the characteristic remanent magnetization (ChRM). The declination values of ChRM are highly discordant before and after structural correction. While inclination values show uniformity in geographic coordinates. The ChRM carried by magnetite yields downward inclinations, whereas the ChRM carried by hematite or titanohematite have upward inclinations in geographic coordinates. The correlation between polarity state and magnetic mineralogy suggests that the acquisition of magnetization occurred during two distinct time intervals. An inclination only fold test of ChRM of these two mineral assemblages indicates that they are post-folding magnetizations. The calculated paleolatitudes for ChRM carried by magnetite and hematite or titanohematite are 9±4• N and 13±4• N respectively. A comparison of these paleolatitudes with the Indian apparent polar wander path (APWP) shows that the remagnetization likely happened between 55 to 45 Ma. Discordant declinations indicate that these volcanics suffered local rotations after remagnetization event.

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The Kohistan arc was formed due to subduction of neo-Tethyan oceanic crust beneath Asia. The arc is comprised of volcanic, plutonic and sedimentary rocks of Mesozoic to Tertiary age, formed prior and after the suturing of the Indian and Asian continents. Paleomagnetic investigations have been carried out on Paleocene volcanic and plutonic rocks exposed in the northern part of the arc. A total of 110 samples from 16 sites were drilled. According to rock-magnetic studies the main magnetic carrier is magnetite. Optical microscopy study reveals that low-grade metamorphism have effected all rocks. Magnetite is found as both a primary magmatic mineral and secondary alteration product in all samples. Samples of volcanics yield post tilting characteristic remanent magnetizations (ChRM). The in situ mean direction of the ChRMs of the intrusives is similar to the in situ mean direction of volcanics. The presence of secondary magnetite in plutons, the similarity of in situ mean ChRM of plutons with that of post-tilting ChRMs of similar age volcanics and dissimilarity of the mean ChRM of plutons from expected directions at the time of formation of plutons support a secondary origin for the ChRM of plutons. As the ChRM directions of the volcanics and intrusives are the same, it implies that both ChRMs were acquired during the same remagnetization event. Comparing the mean paleolatitude (25 ± 6• N) from Gupis area with those from Indian APWP and considering the fact that there was prevailing heating event in Lower Tertiary in the area, the acquisition age of this secondary remanent magnetization can be bracketed between 50 and 35 Ma.