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Published paleomagnetic data from the Pontides indicate anomalously low Jurassic and Early Cretaceous paleolatitudes compatible with the southern Neo-Tethyan (African) continental margin and significantly different from paleolatitudes predicted for the northern (Eurasian) Neo-Tethyan margin. We present a new set of paleomagnetic data from 50 Late Cretaceous sites mainly from the Western Pontides and from the Eastern Pontides, and 11 Early Jurassic sites mainly from the Eastern Pontides. Fold tests indicate that the characteristic magnetization components predate Eocene folding. Late Cretaceous site mean declinations are northerly in the Eastern Pontides and rotated to the west by a few tens of degrees in the Western Pontides. Late Cretaceous site mean declinations are affected by local clockwise rotation in one sampling region close to the North Anatolian Fault. The mean Late Cretaceous inclinations and resulting paleolatitudes are 41.1° (23.5°N) and 43.7° (25.5°N) for the Western and Eastern Pontides, respectively. For the Eastern Pontides, the Early Jurassic (Liassic) mean inclination is 60.5°, yielding a paleolatitude of 41.4°N, considerably further north than previous paleolatitude estimates for the Eastern Pontides at this time. The paleolatitude estimates for the Western and Eastern Pontides are consistent with these units being close to the Eurasian continental margin during Liassic and Late Cretaceous time.

Prefolding high unblocking temperature magnetization components have been resolved from 28 sites of red siltstones from the Lower Triassic Werfen Formation in the Dolomites (Southern Alps). Site mean declinations are more scattered than site mean inclinations, indicating small-scale relative rotation among thrust sheets, particularly in the eastern part of the Dolomites affected by “Dinaric” (Paleogene) thrusting. Two sites from close to the Valsugana Line indicate large-scale (∼80°) anticlockwise rotation in this zone of Alpine sinistral transpression. The overall mean direction (number of sites (N) = 26, Declination = 331°, Inclination = 13°, α95 = 6.6°), excluding sites close to the Valsugana Line, gives a pole position (Latitude = 42°N, Longitude = 233°E, dp/dm = 3.4°/6.8°) which lies close to published Early Permian poles from the Southern Alps and to Permian and Early Triassic poles for Africa, implying very little net rotation of the Dolomites relative to Africa since Permian time.

Jurassic and Cretaceous paleomagnetic data from 46 sites in the Venetian Alps, Trento Plateau and SE Lombardian Basin have been compiled. Nine of these site mean directions have been previously published. The sites can be divided into four age groups (Senonian, Hauterivian/Barremian, Kimmeridgian/Tithonian, and Callovian/Oxfordian). For three of the age groups, positive regional fold tests indicate (at the 99% confidence level) that the characteristic magnetization components predate the deformation. Structural mapping in the Venetian Alps allowed us to assign sites to individual thrust sheets, and we observe no significant relative rotation of thrust sheets in the nappe pile. Indeed, we observe remarkable consistency in mean direction throughout the entire sampling area for each of the four age groups. The Senonian and Hauterivian/Barremian pole positions lie close to coeval poles on African apparent polar wander paths (APWPs). This result is consistent with previous analyses of middle and Late Cretaceous data from the Venetian Alps. The new Jurassic poles deviate significantly from recently published African APWPs, reflecting either the poor definition of the African APWP in the Late Jurassic or about 20° anticlockwise rotation of the Southern Alps relative to Africa during Early Cretaceous time. The former of the two possibilities is favored by a new Late Jurassic/Early Cretaceous pole from North America, and by Early Permian paleomagnetic data from the Southern Alps which are consistent with coeval African data, implying that the movement of the Southern Alps was similar to that of Africa since Early Permian.

Prefolding magnetization components have been resolved at 38 sites of Liassic “Adnet” limestones in the central Northern Calcareous Alps (NCA) and at one site in the Drauzug. The site mean directions are northeasterly and down, and are closer to coeval European directions than to Southern Alpine “African” directions. The western end of both the NCA and of the Drauzug yield different site mean directions and negative fold tests indicating remagnetization. The sampling localities have been rotated relative to one another during thrusting, however, comparison of paleomagnetic poles with the European apparent polar wander path implies an average clockwise rotation of about 30° for the NCA relative to Europe. Larger-scale clockwise rotations in excess of 80°, relative to the Southern Alps, are implied by comparison with the Southern Alpine (African) polar wander path. Facies analysis of Jurassic and Lower Cretaceous basinal sediments in the central part of the NCA suggests that Liassic subsidence was related to presently E-W sinistral strike-slip faults, whereas Malm-Berriasian subsidence was controlled by presently E-W south-dipping normal faults. Both paleomagnetic and facies data tend to indicate that the NCA did not undergo the “African” rotation seen in Southern Alpine paleomagnetic data. This implies the existence of a short-lived tract of Triassic?-Jurassic ocean floor between the NCA and the Southern Alps, which linked the Pindos Ocean to the Ligurian trough and allowed Adria to rotate independently from the NCA during the Late Jurassic. Eo-Alpine deformation and metamorphism are associated with the Early Cretaceous closure of this “Hallstatt” trough.

New paleomagnetic data from the west Sicilian fold and thrust belt indicate large-scale clockwise rotations during tectonic transport. For the platform and seamount paleogeographic units of the fold and thrust belt (Panormide and Trapanese units), there is a general consistency in the magnitude of rotation along strike, suggesting the existence of large coherent structural units. For the Panormide platform, clockwise rotations in the range of 90° to 140° relative to the underlying Iblean parautochthon are recorded along 125 km of outcrop strike. In the case of the Trapanese unit, clockwise rotations in the range of 47° to 70° relative to Iblei are recorded along about 90 km of outcrop strike. Intervening basinal paleogeographic units (Imerese and Sicanian units) show clockwise rotations of similar magnitude; although few reliable data are available from these units. Palinspastic reconstruction of the thrust belt, incorporating the rotations and arguments for the present orientation of the margins of the paleogeographic units, implies that the Panormide platform and Trapanese seamounts were originally elongated more or less north-south relative to the present orientation of Iblei. The two units apparently coalesced to the south and were discontinuous to the north. They and their intervening basins were part of a passive continental margin which occupied a large part of the area that was subsequently rifted to form the Tyrrhenian Sea.

In the western Sicilian fold and thrust belt, large clockwise rotations of allochthons occurred during late Cenozoic contraction of part of the southern Tethyan margin. The magnitude of rotation decreases stepwise from over 120° in the upper sheets, lying on the north coast of Sicily, to no appreciable rotation in the frontal portion of the belt flanking the southern coast of the island. The allochthons are composed of imbricate thrust sheets derived primarily from individual basin and platform assemblages of the old Tethyan margin. Paleomagnetic and structural data indicate that the rotation of the allochthons was accommodated by coherent torsional displacements on relatively low-angle detachment surfaces. Timing relations for the imbrication history of the Sicilian fold and thrust belt are derived from stratigraphic overlap and local involvement of sediments deposited in a series of foreland and piggyback basins. The locus of deposition within successive foreland basins first migrated easterly then southerly during progressive deformation in the orogen. Imbrication began in the early Miocene (Burdigalian-Langhian) and continued at least through the early Pleistocene and appears to be continuing today. Rotation is related to thrusting and accompanies a 70° change in the tectonic transport direction from easterly to southerly. Easterly striking, right-oblique transpressional faults and associated northeasterly trending folds postdate thrust sheet rotation in the interior of the thrust belt and were active contemporaneously with south-directed thrusting in the foreland region. Pleistocene and possibly older (late Pliocene?) extension strongly modified the older thrust morphology along the Tyrrhenian coast of northwestern Sicily, with the development of down-to-the-north listric normal faults. The extensional structures apparently are related to the opening and subsequent deformation of the Tyrrhenian Sea to the north.

Paleomagnetic results from eight sites in argillaceous metasediments from Union County, North Carolina, in the central Carolina slate belt yield a consistent high blocking temperature magnetization component. The precision of the mean declination and inclination of all site means is maximized at 50% tilt correction, and the improvement in grouping relative to 0% and 100% tilt correction is significant at the 95% confidence level. This tends to indicate that the high blocking temperature component was acquired during folding. The metamorphism and deformation in this area are rather well constrained, by recent 40Ar/39Ar data, to the Late Ordovician (−450 Ma). We therefore interpret the computed pole position (29.6°N, 122.1°E, α95 = 5.11) as Late Ordovician in age and note that it lies close to some of the Late Ordovician poles for cratonic North America. The paleolatitude (22.2°S) of the sampling site is certainly unlike those derived from Armorica and Gondwana for this time interval and is rather similar to that proposed for the Iapetus coast of Laurentia during the Late Ordovician. Indeed, the magnetization (and deformation) may be contemporaneous with the docking of the Carolina slate belt onto the Laurentian continent.

We have conducted a paleomagnetic study of limestones and chalks from Haiti which suggests that the island of Hispaniola is a composite of at least two tectonically independent blocks. Sampling sites are distributed among three widely separated localities, namely: Les Cayes (nine sites; 18.3°N. Latitude; 73.6°W. Longitude) and Beloc (five sites; 18.4°N. Latitude; 72.6°W. Longitude) which are located on the southern peninsula of Haiti, and a northern locality, Ennery (six sites; 19.5°N. Latitude; 72.5°W. Longitude). Stable magnetization components of dual polarity and moderately high blocking temperature were revealed through progressive thermal demagnetization of samples from all of the Beloc and Ennery sites, while seven of the nine Les Cayes sites possessed unstable magnetizations. Mean paleolatitudes calculated from Beloc and Ennery data show 8° of latitudinal separation that is of at least Eocene age. Pole positions (Beloc: 43.2°N. Latitude; 185.8°E. Longitude, α95=25.1° and Ennery: 66.1°N. Latitude; 31.3°E. Longitude, α95=19.7°) show both colatitudinal and angular discordance with the North American apparent polar wander path. Based on these disparities, we demonstrate that the implied tectonic displacements tend to support some aspects of previously published Caribbean plate tectonic models.