matter is the major contributor to the organic carbon in the sediments. 2. Higher MARoc values generally characterize glacial periods in the west Caroline Basin and the results of spectral analysis show that the fluctuations of the MARoc are controlled by the global climatic changes in this region. And the fluctuation of MARoc at the Eauripic Rise also shows weak relation with the climatic changes. Although, other regions such as the Ontong Java Plateau and the North Fiji Basin has not shown the relation between MARoc and climatic changes.3. The MARoc in the western equatorial Pacific has a tendency to increase as the modern primary productivity increase.
Fig. 4
Amplitude-density spectra of MARoc of the four core. Dashed lines indicate the smoothed spectrum of total amplitude, while under solid line fields represent the setimates of coherent amplitude density.
6.ACKNOWLEDGMENTS
The authors would like to express their appreciation to Prof. H.Ujiie (University of the Ryukyus) for valuable discussions and suggestions and to Mr.N. Ahagon for providing a program for spectral analysis. This study was supported by the following research programs;" Northwest Pacific carbon cycle Study" consigned the the Kansai environmental engineering Center Co. Ltd. by the New Energy and Industrial Technology Development Organization and "Study on Paleoceanography" by Geological Survey of Japan.
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