Journal of Tropical Oceanography ›› 2010, Vol. 29 ›› Issue (5): 49-55.doi: 10.11978/j.issn.1009-5470.2010.05.049cstr: 32234.14.j.issn.1009-5470.2010.05.049

• Marine geology • Previous Articles     Next Articles

Composition and diagenesis of low-mature hydrocarbon and its interaction with some elements from Core W2001-2 in the Eastern Pacific Ocean

ZHANG Hai-sheng1,2, YU Pei-song1,2, NI Jian-yu1,3, YAO Xu-ying1,3   

  1. 1. Second Institute of Oceanography, SOA, Hangzhou 310012, China; 2. Laboratory of Marine Ecosystem and Biogeochemistry, SOA, Hangzhou 310012, China; 3. Laboratory of Submarine Geosciences, SOA, Hangzhou 310012, China
  • Received:2009-04-14 Revised:2010-01-05 Online:2010-10-30 Published:2011-10-10
  • About author:张海生(1953—), 男, 浙江省岱山县人, 研究员, 博导, 主要从事海洋地球化学和古海洋环境研究。E-mail: zhangsoa@163.com
  • Supported by:

    国家自然科学基金(40676061;41076072)和大洋矿产资源勘探开发专项(DY105-02-01)联合资助

Abstract:

Core W2001-2 was obtained with a multi-tube sampler in the Eastern Pacific Ocean at water depth of 5102 m (154?07?42?W, 10?30?34?N). Chloroform bitumen “A,” organic matters and microelements were analyzed in order to investigate the effect of organic matters on sediment diagenesis. The results showed that the distribution of Core W2001-2 presented obvious changes, especially at the lines of 21—33 cm and 33—48 cm. The n-alkanes showed dominance in C25 and distribution in unimodality. The CPI (carbon preference index) value was between 0.90 and 1.26 with a slight odd-even predominance, indicating that organic matters sourced mainly from deeper submarine ooze as well as a little from marine algae. The lower ratios of Pr/Ph (<0.81) suggested a strong reducing environments. The characteristics of low contents of saturated hydrocarbon and aromatic hydrocarbon, with high contents of non-hydrocarbon compounds including non-hydrocarbon and asphaltene that amount is in the range of 49.63% to 59.66%, indicated that the property of the sediment was at a low-mature stage. The results also showed that organic matters and chloroform bitumen “A” had a positive relativity to Ti and V, but an inverse relativity to P, Mg and Mn. These relations confirmed the interactions between organic matters and some elements under low-mature conditions.

Key words: the Eastern Pacific Ocean, low-mature hydrocarbon, biomarker, composition, diagenesis