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This paper presents results of a paleomagnetic study of Oligo‐Miocene red beds of the Tadjik depression in Central Asia. We sampled about 530 cores at 69 sites and six localities across the depression and along the western border of the Pamirs. Samples were thermally demagnetized and high‐temperature components appear to predate folding of upper tertiary age. Throughout the depression, paleomagnetic inclinations are consistent with those observed on the stable Turan platform, at the western margin of the depression. However, they are shallower by about 30° than the inclination predicted from the reference apparent polar wander path. This appears to indicate a 23° difference in latitude, which is incompatible with paleogeographic reconstructions for the Tertiary. A sound interpretation of this anomaly would require a better‐constrained Tertiary paleomagnetic reference for Asia. Inside the Tadjik depression, paleomagnetic declinations are all significantly rotated, counterclockwise with respect to those measured on the Turan platform. The eastern part of the depression is a domain of large rotation (52°±13° to 46°±15°), whereas smaller amounts of rotation have occurred in the western part (27°±14° to 14°±15°). The similarity between Tertiary and Cretaceous data available for the area shows that rotations have occurred since the Miocene. Little or no paleomagnetic rotations are observed in the ranges bordering the northern and western parts of the depression. Paleomagnetic and structural data suggest that block rotations in the Tadjik depression are associated with indentation of the Pamirs into stable Asia. At a larger scale, observed rotations are compatible with a model of regional sinistral wrenching, along a strip running from the Gulf of Oman to Lake Baikal.

As part of a general investigation of Cenozoic deformation in Central Asia, we studied the paleomagnetism of Tertiary red beds and lava flows from intermontane basins in the Tien‐Shan region of Kyrgyzstan. We collected 532 cores and hand samples from 78 sites at 12 localities and progressively demagnetized them, thermally or with alternating fields. For most sites, there are magnetic components with unblocking temperatures higher than 600°C. We infer that the magnetic carriers are mainly hematite and magnetite. For most localities, the high‐temperature component appears to predate tectonic folding. For all localities, mean inclinations are shallower than expected from apparent polar wander paths. Inclination anomalies range from 16°±5° for the Issyk‐Kul basin, to 26°±7° for the Fergana basin. If due to changes in latitude, these anomalies imply at least 2000 km of northward displacement of the Tien‐Shan during the Tertiary, for which there is no tectonic evidence. We thus consider that the paleomagnetic reference directions cannot be directly compared with our Tertiary data. We explored other possible reasons for this anomaly, which has also been reported from other parts of the Alpine belt, but we could not find a satisfactory explanation. Absolute rotations cannot be accurately determined, because of problems with the reference direction. Nevertheless, the mean declination for the Fergana basin lies counterclockwise by 20°±11° from the mean declination of the Issyk‐Kul basin. This result is consistent with the counterclockwise rotation inferred for the Fergana basin from the pattern of Cenozoic faults and folds. It suggests a Cenozoic right‐lateral displacement of 110±60 km on the Talas‐Fergana fault.

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