This paper reports a paleomagnetic study of Jurassic rocks from the Ordos Basin in the North China Block (NCB). A recent remagnetization and a high‐temperature and/or high‐coercivity component with dual polarities have been isolated. The Middle Jurassic pole (74°N, 233°E, A95=5°) is roughly consistent with previous results, and the Lower Jurassic pole (82°N, 286°E, A95=7°) is located between the late Triassic and Middle Jurassic poles. These results, combined with paleomagnetic results from adjacent blocks, suggest that 1) the pole for the NCB suffered an angular displacement of 47°+/− 8° between the late Triassic and Middle Jurassic, 2) the SCB underwent final accretion to the NCB in the Middle Jurassic, and 3) accretion of the NCB to Siberia was not complete until the late Jurassic and possibly even until the early Cretaceous.

Upper Jurassic to lower Tertiary sites have been sampled from three localities, separated by up to 150 km, in the Sichuan Basin (∼30°N, 103°E) of the South China Block. Each locality has at least one stability test, but none alone gives a fully reliable result. When taken together, however, identical directions are found with a global average D=12.7°, I=34.2°, k=42.9°, α95=3.3° (N=44 sites) and corresponding pole 73.9°N, 234.4°E, dp=2.2°, dm=3.8°, paleolatitude λ=18.8°. There is no significant apparent polar wander (APW) with age, which is consistent with an acquisition of magnetization during the period of the stable tip of the Eurasian APW loop (∼130–70 Ma), as defined with poles from other continents transferred onto Eurasia. This age range is compatible with the available paleontological and magnetostratigraphic age constraints but is shorter than that suggested by the assigned formation ages. The paleolatitude of Sichuan is significantly lower (8.0°±4.0° at 90 Ma) than that predicted by the reference APW path, either because of northward shortening during the Tertiary or because of errors in the APW path. Cretaceous poles from other Chinese blocks are consistent with the Sichuan pole, but there is evidence that these blocks have suffered local rotations up to 10° during the Tertiary, probably as a result of the India‐Eurasia collision.

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To contribute to the apparent polar wander path (APWP) of the South China Block and Eurasia in general, we collected paleomagnetic samples from Mesozoic red beds around the city of Ya' an (30°N, 103°E) in the western tip of the Sichuan Basin. In this paper we present the results from 373 oriented cores taken from one section representing 3 km of sedimentary rocks. The section is dated with continental ostracods and with a magnetostratigraphic correlation between a densely sampled 272‐m sequence and the polarity time scale, giving an upper Jurassic to Upper Cretaceous or Lower Tertiary age. The remanent direction is remarkably stable throughout the section (D=2.0°, I=34.2°, k=63.1,α95=3.6°, N=26/28 sites). While this fact might suggest that the section has been remagnetized, paleomagnetic and rock magnetic tests indicate that the remanence is primary. The pole position (78.6°N, 273.4°E, dp=2.4°, dm=4.1°) corresponds to a rather low paleolatitude (λ=18.8°±2.4°) but is consistent with other Cretaceous poles from China. If one accepts the Eurasian APWP of Irving and Irving (1982), this result would imply that more than 1000 km of shortening took place between South China and Eurasia, following the acquisition of the remanence. However, there is no geological evidence for this large shortening. We propose that the remanence was acquired within the time corresponding to the tip of the hairpin turn (∼150–50 Ma) in the revised APWP of Besse and Courtillot (this issue). The local geology suggests that the syncline from which the samples were taken has been rotated by 15°±5° counterclockwise, which is reflected in a similar discrepancy between the measured paleodeclination and that predicted by the Besse and Courtillot (this issue) Eurasian APWP. After correcting for this rotation, the pole position is 70.9°N, 225.2°E (dp=2.4°, dm=6.5°). We conclude that Eurasia was fully assembled by the end of the Jurassic and that the Mesozoic Eurasian hairpin turn is a real feature.

Summary A palaeomagnetic study of Lower Cretaceous continental sediments from the south‐southwestern part of the Ordos basin, North China block (NCB), has been carried out. Stepwise thermal demagnetization was used to isolate magnetic components. The low‐temperature component is generally removed between 200 °C and 350 °C and corresponds to the Earth's present field direction. A high‐temperature component of magnetization, with two polarities, was defined from 10 sites with D = 16.4°, I = 50.5° (K= 50.8, α95= 6.8°). The corresponding pole position is located at 75.8°N, 208.7°E (dp= 6.1°, dm= 9.1°). This Lower Cretaceous pole compares well with the hairpin loop of the Eurasian synthetic APW path (Besse & Courtillot 1991) that is inferred from the North American, Eurasian, African and Indian plates. The available late Mesozoic palaeomagnetic data from the NCB and adjacent South China block (SCB) are reviewed. Comparison of these data suggests important intraplate deformation: the area to the east of the Tancheng‐Lujiang fault may have undergone local clockwise post‐Cretaceous rotations of 10‐29° relative to the stable western craton of the NCB. The data also indicate that no palaeomagnetically significant eastward movement of the SCB with respect to the NCB and Eurasia occurred after the Cretaceous.

A palaeomagnetic study of Middle to late Cretaceous redbeds from Linzhou basin (Lhasa block), north of the Yarlung Zangbo suture zone, gives a stable palaeomagnetic direction of magnetization with a positive foldtest: six sites, 57 samples, D = 333", I = 38", k = 78, ag5 = 8", pole 64"N, 348"E. We discuss the problem of a possible remagnetization but consider that this direction of magnetization gives a good approximation for the palaeolatitude of the Lhasa block during Middle to late Cretaceous time. Results from more recent Tibetan formations are also presented: late Cretaceous to Palaeocene sediments and volcanics give a lower palaeolatitude of 10"N and but more recent andesites have emplaced about 30"N, close to the present-day latitude. An interpretation is proposed whereby the Lhasa block, which was a part of Asia in the early Cretaceous, has undergone first a southward motion accompanied by an anticlockwise rotation and then, after the Palaeocene, a northward motion under the constraint of the colliding India.

In order to constrain better the paleogeography of the blocks that now make up China, we collected paleomagnetic samples from Uppermost Permian to Middle Triassic limestones from two localities in the Sichuan Basin (South China Block). A low inclination component which passes both the fold test and the reversal test was found in five sites (D=46.1°, I=11.9°, k=83.6, α95=8.7°). We review corresponding remanences found in other studies of Permo‐Triassic rocks from the Sichuan Basin, and show that the component is probably characteristic of the Lower Triassic. We then review paleomagnetic results from the Uppermost Permian Emeishan Basalt. Despite small local rotations, the difference between the Emeishan Basalts and the Sichuan Basin poles is interpreted to be the result of motion of the whole South China Block around the time of the Permo‐Triassic boundary rather than of strain within the block.