An alternative view of the Gondwana Paleozoic apparent polar wander path

1977 ◽  
Vol 14 (11) ◽  
pp. 2674-2678 ◽  
Author(s):  
P. W. Schmidt ◽  
W. A. Morris

A reappraisal of Paleozoic paleomagnetic data from Australia is given. An alternative apparent polar wander path is suggested after adopting the reversed polarity option for pre-Devonian poles. Hitherto 'anomalous' Siluro-Devonian pole positions thus appear as conformable. This new polar path is compared to Paleozoic paleomagnetic data from other Gondwana continents which are seen to support the Australian path. The new path, in turn, supports the interpretation of Paleozoic glacial deposits being indicative of high latitudes and the transgression of an ice cap.It is suggested speculatively that systematic polar wandering of the type described here may indicate a systematic pattern of plate motions and consequently, systematic tectonic processes.


2019 ◽  
Vol 132 (3-4) ◽  
pp. 710-738 ◽  
Author(s):  
Athena Eyster ◽  
Benjamin P. Weiss ◽  
Karl Karlstrom ◽  
Francis A. Macdonald

AbstractPaleogeographic models commonly assume that the supercontinent Rodinia was long-lived, with a static geometry involving Mesoproterozoic links that developed during assembly and persisted until Neoproterozoic rifting. However, Rodinian paleogeography and dynamics of continental separation around its centerpiece, Laurentia, remain poorly constrained. On the western Laurentian margin, geological and geochronological data suggest that breakup did not occur until after 720 Ma. Thus, late Tonian (ca. 780–720 Ma) paleomagnetic data are critical for reconstructing paleogeography prior to dispersal and assessing the proposed stasis of Rodinia. Here, we report new paleomagnetic data from the late Tonian Chuar Group in the Grand Canyon, Arizona. We combined this new data set with reanalyzed existing data to obtain a new paleopole preserved in hematite, the reliability of which is supported by six of the seven (Q1–Q6) Van der Voo reliability quality criteria. In addition, we identified pervasive mid- to high-temperature overprints. This new paleomagnetic pole was incorporated with recent high-precision geochronological data and existing paleomagnetic data to present a new late Tonian Laurentian apparent polar wander path (APWP). Having examined the paleomagnetic data of other cratons, global reconstructions for 775 Ma, 751 Ma, and 716 Ma are presented. These reconstructions are consistent with Australia located near the present southern margin of Laurentia. However, a stringent analysis of the global data set does not support a good match between any major craton and the rifted conjugate margin to western Laurentia. Breakup on the western Laurentian margin may have involved rifting of a continental fragment or a craton with uncertainties in its late Tonian geochronologic and paleomagnetic constraints. Our revised Laurentian APWP will allow for more robust tests of paleogeography and evaluation of the proposed supercontinent Rodinia.



2016 ◽  
Vol 285 ◽  
pp. 80-90 ◽  
Author(s):  
Mikhai L. Bazhenov ◽  
Natalia M. Levashova ◽  
Joseph G. Meert


2019 ◽  
Vol 489 (4) ◽  
pp. 379-383
Author(s):  
I. V. Golovanova ◽  
K. N. Danukalov ◽  
V. N. Puchkov ◽  
N. D. Sergeeva ◽  
R. Yu. Sal’manova

The paper presents new paleomagnetic data on dated Ordovician-Silurian volcanics from four sections in the western frame of the Taratash massif in the Southern Urals. Geological data indicate that the region under study has been part of the paleocontinent Baltica since the beginning of Mesoproterozoic. Paleomagnetic data from studies of the rocks of the most western part of the Ural fold belt did not reveal local and regional rotations with respect to the Baltica. Consequently, the pole obtained can be extrapolated to the entire platform. The presented result has a fairly high degree of reliability and can clarify the part of apparent polar wander path (APWP) for the paleocontinent Baltica on the Late Ordovician - Early Silurian segment, where reliable paleomagnetic data are not available, and can be used for paleoreconstructions.



2020 ◽  
Author(s):  
Aleksandr Pasenko ◽  
Aleksandr Savelev ◽  
Sergey Malyshev

<p>In spite of the fact, that during the last two decades some number of new paleomagnetic poles, more or less meeting the modern standards of quality [Van der Voo, 1993], have been obtained for Mesoproterozoic of Siberia [Evans et al., 2016]. The problem of the Precambrian segment of the apparent polar wander path (APWP) for Siberia, rests still to be far from its solution.</p><p>The latter, obviously, hampers the elaboration of Precambrian paleogeographic reconstructions, solution of numerous other important tasks of the Earth Sciences.</p><p>The Late Precambrian key section of the Udzha Uplift seemed to be one of the most promising object to elaborate the Mesoproterozoic segment of APWP of the Siberian platform. Until recently, the rocks composing this section have been considered to be of the Mesoproterozoic and Vendian age.</p><p>As a result of isotope studies in recent years, the age of formations of the Udzha Uplift has been significantly increased (1386±30 Ma, apatite, U-Pb, [Malyshev et al., 2018]). In particular, age of the Udzha Fm, which forms the uppermost part of the Udzha riphean sequence is considered currently to be Mesoproterosoic. On the base of our new paleomagnetic data this formation has been formed about the same time as the Khaypakh Fm from the Olenek Uplift (NE Siberia), whose Mesoproterozoic age has been established earlier from independent isotopic data [Zaitseva et al., 2017].</p><p>During last several years we have carried out the paleomagnetic studies of Late Precambrian rocks of the Udzha Uplift including the Mesoproterozoic Udzha and Unguokhtakh formations as well as intrusions representing two Mesoproterozoic magmatic events.</p><p>In this abstract we present new paleomagnetic poles for the Mesoproterosoic rocks (1500 Ma, ca.1400 Ma, 1385 Ma) of the Siberian platform.</p><p>These paleomagnetic poles significantly complement the Mesoproterozoic segment of APWP of the Siberian Platform.</p><p><em>The studies were supported by the Russian Science Foundation project № 19-77-10048.</em></p>



1993 ◽  
Vol 30 (9) ◽  
pp. 1898-1913 ◽  
Author(s):  
David R. Richards ◽  
Robert F. Butler ◽  
Tekla A. Harms

Paleomagnetic samples were collected from Mid-Pennsylvanian to Lower Permian red argillaceous cherts at two localities of the Slide Mountain terrane: 18 sites from the Sylvester allochthon in northern British Columbia and 11 sites from Sliding Mountain in central British Columbia. A secondary component of natural remanent magnetization in the Sylvester samples yields a paleomagnetic pole that can be brought into coincidence with the Jurassic portion of the North American apparent polar wander path by inferring vertical-axis rotation during obduction of the allochthon. Both localities yield a characteristic component (ChRM) with unblocking temperatures from 650 to 680 °C. After structural correction for bedding tilt, all inclinations of ChRM are negative, consistent with magnetization during a reversed-polarity interval in the northern hemisphere. Site-mean ChRM directions show consistent inclinations but distinct stratigraphic groupings of declinations. Inclination-only statistics indicate that the ChRM passes a tilt test within the Sylvester allochthon and regionally between the two localities. The ChRM was apparently acquired prior to structural imbrication within the Sylvester section and regional differential tilting. We interpret the ChRM to be a primary magnetization acquired at or soon after deposition during the Permo-Carboniferous reversed-polarity superchron. The mean ChRM inclination of −16.7° ± 6.0° from the Sylvester allochthon indicates a paleo-latitude of 8.8° ± 3.4°N, which is corroborated by a paleolatitude of 1.9° ± 1.5°N from the Sliding Mountain locality. When compared with expected Pennsylvanian–Permian paleolatitudes, a net poleward translation of 20.3 ± 3.7° is implied for at least the sampled lithotectonic component of the Sylvester allochthon.



2011 ◽  
Vol 12 (7) ◽  
pp. n/a-n/a ◽  
Author(s):  
Mathew Domeier ◽  
Rob Van der Voo ◽  
Eric Tohver ◽  
Renata N. Tomezzoli ◽  
Haroldo Vizan ◽  
...  


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