Palaeomagnetic data from Ediacaran (Vendian) sediments of the Arkhangelsk region, NW Russia: An alternative apparent polar wander path of Baltica for the Late Proterozoic–Early Palaeozoic

2005 ◽  
Vol 240 (3-4) ◽  
pp. 732-747 ◽  
Author(s):  
M LLANOS ◽  
J TAIT ◽  
V POPOV ◽  
A ABALMASSOVA
Keyword(s):  
Polar Wander ◽  
Late Proterozoic ◽  
Arkhangelsk Region ◽  
Apparent Polar Wander Path ◽  
Palaeomagnetic Data ◽  
Early Palaeozoic

Palaeomagnetic evidence for Proterozoic continental development

1981 ◽  
Vol 301 (1461) ◽  
pp. 265-277 ◽  
Keyword(s):  
North America ◽  
High Latitude ◽  
Baltic Shield ◽  
Continental Drift ◽  
Polar Wander ◽  
Late Proterozoic ◽  
Apparent Polar Wander Path ◽  
Orogenic Uplift ◽  
The Baltic ◽  
Opening And Closing

The palaeomagnetic record of continental drift during the Proterozoic is reasonably complete for North America (including Greenland and the Baltic Shield), less complete for Africa and Australia, and fragmentary elsewhere. Palaeomagnetic poles of similar age from different cratons or structural provinces of any one continent tend to fall on a common apparent polar wander path (a.p.w.p.), indicating no major (> 1000 km) intercratonic movements. On this evidence, Proterozoic orogens and mobile belts are essentially ensialic in origin. However, the palaeomagnetic record has systematic gaps. In highly metamorphosed orogens (amphibolite grade and above), remagnetization dating from post-orogenic uplift and cooling is pervasive. Collisional and ensialic orogenesis cannot then be distinguished. Palaeopoles from different continents do not follow a common a.p.w.p. They record large relative rotations and palaeolatitude shifts. A recurrent pattern appears in the late Proterozoic drift of North America. At approximately 200 Ma intervals (at about 1250, 1050, 850 and 600 Ma B.P .), the continent returned to the same orientation and (equatorial) latitudes from various rotations and high-latitude excursions. Lacking detailed a.p.w.ps. from other continents, it is not possible to say if these motions represent Wilson cycles of ocean opening and closing in the Phanerozoic style, but they do require minimum drift rates of 50—60 mm/a, comparable to the most rapid present-day plate velocities.

scholarly journals Palaeomagnetism of the Mahatta Humaid Group (Cambrian – Early Ordovician, Oman), including a re-interpretation of previous Neoproterozoic palaeomagnetic data

GeoArabia ◽  
2009 ◽  
Vol 14 (2) ◽  
pp. 71-96
Author(s):  
Haroldo Vizán ◽  
Peter Turner ◽  
John A. Millson ◽  
Rob A. Ixer
Keyword(s):  
Remanent Magnetization ◽  
Sedimentary Basins ◽  
Vertical Axis ◽  
Petrographic Analysis ◽  
Polar Wander ◽  
Magnetic Carriers ◽  
Palaeomagnetic Data ◽  
Primary Origin ◽  
The Mean ◽  
Early Palaeozoic

ABSTRACT We carried out a palaeomagnetic study in the Al-Huqf region (Sultanate of Oman) on rocks that belong to different units of the Cambrian – Ordovician Mahatta Humaid Group. Thirty-nine samples were systematically collected from a succession ca. 520–495 Ma old. Seventeen samples showed characteristic remanent magnetization components with two antipodal polarities carried by hematite. Evidence suggests that these components have a primary origin. A detailed petrographic analysis revealed syntaxial overgrowths parallel to the easy plane of magnetization of the magnetic carriers that has probably enhanced and reinforced the primary magnetization. A palaeopole computed with the mean direction of the 17 characteristic remanent magnetization components was considered alongside previously published Neoproterozoic – early Palaeozoic palaeomagnetic data, which we placed in an updated chronostratigraphic framework for the Neoproterozoic – Cambrian Huqf Supergroup. Two interpretations were considered: (1) Oman was detached from the Arabian-Nubian craton until ca. 660 Ma, and it became attached (or was nearby) to it by ca. 630 Ma. In this interpretation, an apparent polar wander (APW) path of Arabia is proposed between ca. 630 and 500 Ma. The palaeomagnetic directions of Mirbat obtained by Killner et al. (2005) in rocks 720–660 Ma old are therefore assumed as primary, and taking into account that Oman was an independent block of the Arabian-Nubian craton, the corresponding palaeopole is not considered in the proposed segment of the Arabian APW path. (2) The Neoproterozoic data belong to two different tectonic blocks within the Arabian-Nubian craton and were involved in left-lateral, strike-slip movements along NW-trending faults. One block included the localities of Al Jabal al-Akhdar and Al-Huqf and may have rotated counter-clockwise c. 45° about a vertical axis between ca. 600 and 500 Ma. The other block included the locality of Mirbat and rotated counter-clockwise c. 25° about a vertical axis between ca. 600 and 550 Ma. These suggested block rotations may have played a role in generating the underlying fabrics for some of the sedimentary basins in Oman. In the second model, the rocks sampled by Killner et al. (2005) in Mirbat were re-magnetized during the intrusion of dike swarms at ca. 615–600 Ma.

Preliminary Proterozoic apparent polar wander paths for the South China Block and their tectonic implications

1998 ◽  
Vol 35 (3) ◽  
pp. 302-320 ◽  
Author(s):  
Huimin Zhang
Keyword(s):  
South China ◽  
North China ◽  
Eastern China ◽  
North China Block ◽  
Polar Wander ◽  
Late Proterozoic ◽  
The North ◽  
Apparent Polar Wander Path ◽  
Paleomagnetic Study ◽  
Middle Proterozoic

Results of a regional paleomagnetic study of Precambrian rocks in central-east China are summarized and interpreted. The study is a partial outcome of a geoscience transect incorporating three terranes, namely the Yangzi, Jiangnan, and Huaxia blocks. Paleomagnetic poles derived from a range of metamorphic, igneous, and sedimentary rocks define a northeast to southwest swath crossing the present Pacific Ocean and interpreted to embrace Early to Late Proterozoic times. All three terranes define segments of the same swath and correlate with a similar apparent polar wander path previously defined from the North China Block. The results imply that the constituent blocks of eastern China formed a united block during Early to Middle Proterozoic times. Later relatively large fragmentation is confirmed by Late Proterozoic apparent polar wander path records of the North China and South China Blocks.

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