We have conducted a paleomagnetic study of Late Quaternary sediments from Lake Malawi, East Africa, in order to develop a high-resolution record of paleomagnetic secular variation (PSV). This study has recovered PSV records from two cores (3P, 6P) in northern Lake Malawi (10.0°S, 34.3°E). The PSV appears to be recorded in fine-grained detrital magnetite/titanomagnetite grains. Detailed af demagnetization of the natural remanence (NRM) shows that a distinctive characteristic remanence (ChRM) is demagnetized from ~20-80 mT, which decreases simply toward the origin. The resulting directional PSV records for 3P and 6P are easily correlatable with 29 distinct inclination features and 29 declination features. The statistical character of the PSV in both cores is consistent with Holocene PSV noted at other Holocene equatorial sites. Radiocarbon dating of the cores is based on 18 independent radiocarbon dates and four dated stratigraphic horizons that can be correlated into each core. The final directional PSV time series cover the last 24,000 years with an average sediment accumulation rate of ~30 cm/kyr. We have also developed a relative paleointensity estimate for these PSV records based on normalizing the NRM (after 20 mT af demagnetization) by the SIRM (after 20 mT af demagnetization). Changing sedimentation patterns complicate any attempt to develop a single paleointensity record for the entire core lengths. We have developed a relative paleointensity record for the last 6000 years that has 14 correlatable features including 5 notable peaks in intensity. Three of these peaks are synchronous with paleointensity highs farther north in SE Europe/SW Asia/Egypt but two of the peaks are at times of low paleointensity farther north. We interpret this to indicate that Lake Malawi (10°S) is at least partly under the influence of a different flux-regeneration region of the outer-core dynamo. A relative paleointensity record was also developed for ~11,000-24,000 YBP; the general pattern appears to be consistent with other published records, but our confidence in the correlations is more limited.

No abstract available. <br><br> doi:<a href="http://dx.doi.org/10.2204/iodp.sd.14.08.2012" target="_blank">10.2204/iodp.sd.14.08.2012</a>

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The Nuclear Regulatory Commission (NRC) staff has tion, and several involve regulatory issues that must be identified 48 sites contaminated with radioactivematerial addressed bythe Commission before they can be released that require special attention to ensure timely decommis-for unrestricted use and the applicable licenses termisioninl. While none of these sites represent an immediate hated. This report contains the NRC staff's strategy for threat to public health and safety, they have contamina-addressingthe technical, legal, and policy issues affecting tion that exceeds existing NRC criteria for unrestricted the timely decommissioning of the 48 sites and describes use. All of these sites require some degree of remedia-the status of decommissioning activities at the sites.

No abstract