6. DATA REPORT: HIGH-RESOLUTION STUDY OF MAGNETIC PROPERTIES OF SAPROPEL-BEARING SEDIMENTS FROM SITES 966, 967, AND 969, EASTERN MEDITERRANEAN SEA1Joseph S. Stoner,2 Carl Richter,3 and Andrew P. Roberts4 |
ABSTRACTHigh-resolution magnetic measurements were performed on sediments recovered from Sites 966, 967, and 969 during Leg 160 of the Ocean Drilling Program to the eastern Mediterranean Sea. Measurements of u-channel samples were made at 1-cm intervals from nearly complete composite stratigraphic sequences at each site. The measurements are integrated over stratigraphic intervals of 4.5 cm, which allows high spatial resolution of sediment magnetic properties, including detailed characterization of variations in magnetic mineralogy, concentration, and grain size, as well as paleomagnetic determinations. We present u-channel magnetic data for more than 100 m of core from three eastern Mediterranean sites. Cyclic variations are observed over short and long stratigraphic intervals, which reflect variations in magnetic concentration and mineralogy of the sediments. The high-frequency variability is related to variations in nonsteady state diagenesis that results from cyclic deposition of organic-rich sapropels. This suggests that magnetic parameters may be an excellent proxy for diagenesis-related cyclicity in these sediments. Longer term changes may reflect significant variations in the climatic evolution of the eastern Mediterranean Sea. |
|