We present here the paleointensity results of basalt samples from Rajmahal (25.10°N; 87.40°E) and Sylhet Traps (25.22°N; 91.71°E) of eastern India (~117 Ma) to know the strength of the earth's magnetic field during the early Cretaceous from these locations. The modified version of the Thellier–Thellier paleointensity method of, in field-zero field-zero field-in field (IZZI) protocol and systematic partial thermoremanent magnetization (pTRM) checks were used for the paleointensity determination. Rock magnetic investigations on these rocks indicate ‘magnetite’ is the main remanence carrier with single domain (SD) to pseudosingle domain (PSD) nature. The samples have yielded low paleofield intensities between 6.97 ± 2.21 and 23.47 ± 2.08 μT (mean 17.20 ± 1.89 μT). The corresponding virtual dipole moment (VDM) ranges from 1.16 to 4.17 × 10²² Am² (mean 2.93 × 10²² Am²) which is approximated as to 30% of the present-day field strength (8 × 10²² Am²). The success rate of the experiment is quite low in the order of 5%, but has provided scope for further, more elaborative paleointensity studies. Our new results compared with published paleointensities from these basalts as well as rocks of Cretaceous normal superchron (CNS) time around the globe are in good agreement.

我们在此展示了来自印度东部（~117 Ma）的 Rajmahal（25.10°N；87.40°E）和 Sylhet Traps（25.22°N；91.71°E）的玄武岩样品的古强度结果，以了解地球磁场的强度这些地点的白垩纪早期。Thellier-Thellier 古强度方法的修改版本、零场零场入场 (IZZI) 协议和系统部分热剩磁 (pTRM) 检查用于古强度测定。对这些岩石的岩石磁性研究表明，“磁铁矿”是具有单畴 (SD) 至伪单畴 (PSD) 性质的主要剩磁载体。样品产生了 6.97 ± 2.21 和 23.47 ± 2.08 μT（平均 17.20 ± 1.89 μT）之间的低古场强度。对应的虚拟偶极矩 (VDM) 范围从 1.16 到 4.17 × 10²² Am ²（平均 2.93 × 10 ²² Am ²），它近似为当今场强（8 × 10 ²² Am ²）的30% 。实验的成功率相当低，大约为 5%，但为进一步、更精细的古强度研究提供了空间。我们的新结果与这些玄武岩以及全球白垩纪正常超时 (CNS) 时间的岩石公布的古强度相比，结果非常吻合。