The Apparent Polar Wander Path For the North China Block Since the Jurassic

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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Constraints on the Jurassic swing of the apparent polar wander path for the North China Block

Geophysical Journal International ◽

10.1046/j.1365-246x.2003.01992.x ◽

2003 ◽

Vol 154 (3) ◽

pp. 801-810 ◽

Cited By ~ 17

Author(s):

Koji Uno ◽

Baochun Huang

Keyword(s):

North China ◽

North China Block ◽

Polar Wander ◽

The North ◽

Apparent Polar Wander Path

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Enigma of the Jurassic monster shift of the North China block

10.5194/egusphere-egu2020-12816 ◽

2020 ◽

Author(s):

Shihong Zhang ◽

Yangjun Gao ◽

Qiang Ren

Keyword(s):

North China ◽

Rotation Axis ◽

Eastern Asia ◽

North China Block ◽

Polar Wander ◽

Plate Convergence ◽

True Polar Wander ◽

The North ◽

Geochronological Study ◽

Oceanic Plates

<p>Accumulation of the global paleomagnetic data, from both continental and oceanic plates, may suggest a true polar wander (TPW) event in Jurassic, with a rotation axis located in the present northwestern Africa, but no consensus has been reached regarding to the initiation, duration and velocity of the TPW. As one of the eastern Asian blocks, the north China block (NCB) is then located far from the rotation axis of the TPW and the plate convergence between Siberia and the Amur-NCB, known as the subduction in the Mesozoic Okhotsk-Baikal ocean, did exist. Paleogeographic changes observed of the eastern Asian blocks in Jurassic thus should contain the TPW component and plate moving component. To better estimate the influence of the TPW in the Eastern Asia blocks, we carried out a new paleomagnetic and precision U-Pb geochronological study on the middle Jurassic lavas in the NCB. Being profoundly different to the recent paleogeographic model (Yi et al., 2019, https://doi .org/10.1130/G46641.1) that suggest that the NCB experienced a large latitudinal displacement (monster-shift) responding to the TPW event between ~174 and ~157 Ma, we suggest that the NCB, as well as other blocks already connected with it, do not record any monster-shift between ~170 and ~160 Ma. The strata, ranging from 160 to 145 Ma, however, yield considerable paleomagnetic variations and need further investigation.</p>

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Author response for "Devonian bimodal volcanic rocks from the northeastern margin of the North China Block: Implications for post‐collisional extension and orogen‐craton boundary"

10.1002/gj.3805/v2/response1 ◽

2020 ◽

Author(s):

Qi‐Qi Zhang ◽

Shuan‐Hong Zhang ◽

Yue Zhao ◽

Guo‐Hao Shui

Keyword(s):

North China ◽

Volcanic Rocks ◽

Author Response ◽

North China Block ◽

The North

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Depositional environments of limestones from the Taiyuan Formation in the North China Block interpreted from REE proxies

Carbonates and Evaporites ◽

10.1007/s13146-020-00580-x ◽

2020 ◽

Vol 35 (2) ◽

Author(s):

Dawei Lv ◽

Wengui Fan ◽

John I. Ejembi ◽

Dun Wu ◽

Dongdong Wang ◽

...

Keyword(s):

North China ◽

Depositional Environments ◽

North China Block ◽

The North ◽

Taiyuan Formation

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Paleomagnetism of the Lawrenceton Formation volcanic rocks, Silurian Botwood Group, Change Islands, Newfoundland

Canadian Journal of Earth Sciences ◽

10.1139/e89-024 ◽

1989 ◽

Vol 26 (2) ◽

pp. 296-304 ◽

Cited By ~ 10

Author(s):

Julie E. Gales ◽

Ben A. van der Pluijm ◽

Rob Van der Voo

Keyword(s):

North American ◽

Volcanic Rocks ◽

Mobile Belt ◽

Structural Mapping ◽

Polar Wander ◽

The North ◽

Apparent Polar Wander Path ◽

Paleomagnetic Study ◽

North American Craton

Paleomagnetic sampling of the Lawrenceton Formation of the Silurian Botwood Group in northeastern Newfoundland was combined with detailed structural mapping of the area in order to determine the deformation history and make adequate structural corrections to the paleomagnetic data.Structural analysis indicates that the Lawrenceton Formation experienced at least two folding events: (i) a regional northeast–southwest-trending, Siluro-Devonian folding episode that produced a well-developed axial-plane cleavage; and (ii) an episode of local north-trending folding. Bedding – regional cleavage relationships indicate that the latter event is older than the regional folding.Thermal demagnetization of the Lawrenceton Formation yielded univectorial southerly and shallow directions (in situ). A fold test on an early mesoscale fold indicates that the magnetization of the Botwood postdates this folding event. However, our results, combined with an earlier paleomagnetic study of nearby Lawrenceton Formation rocks, demonstrate that the magnetization predates the regional folding. Therefore, we conclude that the magnetization occurred subsequent to the local folding but prior to the period of regional folding.While a tectonic origin for local folding cannot be entirely excluded, the subaerial nature of these volcanics, the isolated occurrence of these folds, and the absence of similar north-trending folds in other areas of eastern Notre Dame Bay suggest a syndepositional origin. Consequently, the magnetization may be nearly primary. Our study yields a characteristic direction of D = 175°, I = +43°, with a paleopole (16°N, 131 °E) that plots near the mid-Silurian track of the North American apparent polar wander path. This result is consistent with an early origin for the magnetization and supports the notion that the Central Mobile Belt of Newfoundland was adjacent to the North American craton, in its present-day position, since the Silurian.

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Devonian alkaline magmatic belt along the northern margin of the North China Block: Petrogenesis and tectonic implications

Lithos ◽

10.1016/j.lithos.2018.01.019 ◽

2018 ◽

Vol 302-303 ◽

pp. 496-518 ◽

Cited By ~ 6

Author(s):

Qi-Qi Zhang ◽

Shuan-Hong Zhang ◽

Yue Zhao ◽

Jian-Min Liu

Keyword(s):

North China ◽

North China Block ◽

Northern Margin ◽

The North ◽

Tectonic Implications

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Paleomagnetism of the komatiitic basalts of the Ottawa Islands, N.W.T.

Canadian Journal of Earth Sciences ◽

10.1139/e85-056 ◽

1985 ◽

Vol 22 (4) ◽

pp. 553-566 ◽

Cited By ~ 2

Author(s):

K. L. Buchan ◽

W. R. A. Baragar

Keyword(s):

North American ◽

Hudson Bay ◽

The West ◽

Magnetization Direction ◽

Polar Wander ◽

The North ◽

Dominant Component ◽

Apparent Polar Wander Path

The komatiitic basalts of the Ottawa Islands in eastern Hudson Bay are on strike with and believed to form a continuation of similar units of the Cape Smith Belt 150 km to the northeast. Units sampled in the Ottawa Islands all dip gently to the west and hence are not suitable for an internal fold test of their age of magnetization. However, before correcting for the tilt of the lavas, the dominant magnetization direction (D = 207.6°, I = 61.9°, k = 168, α95 = 3.7°) does not differ significantly from the uncorrected magnetization direction reported from the steeply dipping, northwest-facing units at Cape Smith (D = 218°, I = 60°, k = 47, α95 = 4°). This negative fold test suggests that the remanence at both locations was acquired after folding. Comparison with the North American Precambrian apparent polar wander path implies that overprinting is related to the Hudsonian Orogeny.A second stable magnetization directed to the west with a shallow inclination is superimposed on the dominant component at a number of sampling sites. Its direction is poorly defined and no fold test is possible. However, magnetic evidence suggests that this component was probably acquired as an overprint after the dominant magnetization, perhaps during a mild reheating associated with the Elsonian Orogeny.

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