Abstract
Recent progress in paleomagnetic studies of marine sediments has revealed long-term (10-100 kyr) variations in geomagnetic field intensity (relative paleointensity). The accumulation of relative paleointensity records has enabled the development of a composite geomagnetic-field intensity stack for time intervals spanning the period from the last few tens of thousands of years to the last few millions of years, and has contributed to establishing an age model for marine sediments. This technique is a powerful tool for synchronizing different geological archives, such as marine sediments and ice cores, by comparing the flux of cosmogenic nuclides. This synchronization is essential for understanding the initiation and propagation of changes in the Earth’s climate system. However, there is some controversy concerning the limits of the use of relative paleointensity records in dating marine sediments. For example, uncertainty may be introduced into the synchronization by the lock-in of a paleomagnetic signal at some depth below the sediment-water interface in marine sediments through the acquisition of post-depositional remanent magnetization (PDRM). This article summarizes the current understanding of the PDRM process and provides examples of relative paleointensity-assisted correlation or dating in marine sediments. Also discussed are possible sources of uncertainty and future prospects for the technique.
