Table of Contents
International Journal of Oceanography
Volume 2011 (2011), Article ID 410621, 11 pages
http://dx.doi.org/10.1155/2011/410621
Research Article

Carbon and Oxygen Isotopic Stratigraphy of Mesoproterozoic Carbonate Sequences (1.6–1.4 Ga) from Yanshan in North China

1Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China
2Key Laboratory of Exploration Technologies for Oil and Gas Resources, School of Geophysics and Oil Resources, Yangtze University, Ministry of Education of China, Jingzhou 434023, China
3Insitute of Geosciences, Yangtze University, Jingzhou 434023, China

Received 13 October 2010; Revised 22 December 2010; Accepted 17 January 2011

Academic Editor: Henk Brinkhuis

Copyright © 2011 Kuang Hongwei et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In Yanshan, located in the northern part of North China, Mesoproterozoic carbonate sequences (1.6–1.4 Ga) form a 10, 000 m thick succession in an aulacogen basin. Carbon and oxygen isotope (δ13O and δ18O, resp.) data were obtained from 110 carbonate samples across three sections of these Mesoproterozoic deposits. From the early to late Mesoproterozoic, low negative values of δ13O appear, followed by low positive variation and then a stable increase. An abrupt decrease in δ13O values, with subsequent rapid increase, is found at the end of the Mesoproterozoic. During the whole Mesoproterozoic, δ18O shows a mainly negative trend and occasional highly negative isotopic shifts (from lower to upper deposits). Whole-rock carbon and oxygen isotopic compositions and profiles must be studied to provide a paleogeochemical record that can be associated with paleocean sedimentary environments, temperature, biological productivity, and sea-level fluctuations. Results of the present study correlate well with other international carbon and oxygen isotope profiles, suggesting that a global marine geochemical system existed during the interval of 1.6–1.4 Ga under a globally united tectonic, sedimentary, and geochemical background.