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Acta Oceanologica Sinica 2015年第8期34卷 13-19页

作者： JI Lihong LIU Guangshan HUANG Yipu XING Na CHEN Zhigang College of Ocean and Earth Sciences Xiamen University College of Resources and Environment Linyi University

In the present paper, iodine （I）, iron （Fe）, manganese （Mn）, cobalt （Co）, phosphorus （P） and calcium （Ca） contents in three ferromanganese crusts from the Pacific Ocean are measured by spectrophotometric method and inductively coupled plasma atomic emission spectrometers （ICP-AES） to investigate the contents and distribution of iodine in ferromanganese crusts. The results show that iodine contents in three crusts vary between 27.1 and 836 mg/kg, with an average of 172 mg/kg, and the profile of iodine in the three crusts all exhibits a two-stage distribution zone： a young non-phosphatized zone and an old phosphatized zone that is rich in I, P and Ca. The iodine content ratios of old to young zone in MP5D44, CXD62-1 and CXD08-1 are 2.3, 3.4 and 13.7, respectively. The boundary depths of two-stage zone in MP5D44, CXD62-1 and CXD08-1 locate at 4.0 cm, 2.5 cm and 3.75 cm, respectively, and the time of iodine mutation in three crusts ranges from 17-37 Ma derived from 129I dating and Co empirical formula, which is consistent with the times of Cenozoic phosphatization events. The present study shows that the intensity of phosphatization is the main responsible for the distribution pattern of iodine in the crusts on the basis of the correlation analysis. Consequently, iodine is a sensitive indicator for phosphatization.

关键词： ferromanganese crust iodine phosphatization Mid-Pacific Ocean two-stage distribution

Secondary phosphatization of the Earliest Cambrian Small Shelly Fossil Anabarites from Southern Shaanxi

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Journal of Earth Science 2016年第2期27卷 196-203页

作者： Yali Chen Xuelei Chu Xingliang Zhang Mingguo Zhai State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Continental Dynamics Northwest University Xi' an 710069 China

Biomineralization may have an extremely long evolutionary history since the Paleoarchean, while the widespread biomineralization among metazoan lineages started at the earliest Cambrian. However, the primary mineralogy of Anabarites shell remains controversial. Optical microscopic observations combined with the Back-Scattered Electron（BSE） and Energy-Dispersive X-ray Spectroscopy（EDS） analyses are used to study the shell of the fossil Anabarites from the Kuanchuanpu fauna in southern Shaanxi Province in China, which is correlated to the Cambrian Fortunian Stage. The EDS analysis shows that the phosphorus-rich layer closely adjacent to the calcified layer exhibits a Ca： P： C ratio compositionally similar to the mineral fluorapatite（Ca_5（PO_4,CO_3）_3（F,CO_3）. The result that the calcified layer and the phosphorus-rich layer have different chemical compositions is consistent with the optical observation that there is an obvious gap between these two layers and the phosphorus-rich layer can extend to the phosphatic material inside of the tube, suggesting the phosphorus-rich layer doesn＇t belong to the original shell. We suggest that the phosphorous-rich layer is diagenetic in origin, precipitated as a result of phosphorus release during the decay of organic matter by microbes. Considering the outermost shell layer（OMS, biologically controlled carbonate shell layer） should display different isotopic information from the carbonate matrix（i.e., OMS is ^（12）C concentrated due to the biogenic organic matter template is readily rich in ^（12）C）, Nano SIMS was used to map ion distributions of C and N in the shell of Anabarites and matrix. However, ion images show that the concentration differences of ^（12）C, ^（13）C and ^（26）CN among the OMS and the matrix are unclear, while ^（12）C and ^（26）CN are supposed to be enriched in the OMS. Therefore, the minor isotopic differences between the shell and the matrix is hard to be detected by Nano SIMS, at least in our sample, probably due

关键词： biomineralization Anabarites Fortunian Stage phosphatization NanoSIMS southernShaanxi.

Effect of phosphatization on Element Concentration of Cobalt-Rich Ferromanganese Crusts

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Acta Geologica Sinica(English Edition) 2005年第3期79卷 349-355页

作者： PANJiahuax E.H.DeCARLO YANGYi LIUShuqin YOUGuoqin InstituteofMineralResources ChineseAcademyofGeologicalSciencesBeijing100037China DepartmentofOceanography UniversityofHawaii21000PopeRd.HonoluluHawaii96822U.S.A. TheGraduateSchoolofTheChineseAcademyofSciences YuquanRoad18Beijing100049China

A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust mineral resources. Sub-samples from top to bottom of a 10-cm thick sample from the NW Pacific Magellan seamount were taken at 5 mm intervals. The concentration profiles of ore-forming and rare earth elements show that obvious differences exist between young unphosphatized crusts and old phosphatized crusts. In the old crusts Fe, Mn, Si, Al, Zn, Mg, Co, Ni and Cu elements are depleted and Ca, P, Sr, Ba and Pb elements are enriched. The order of depletion is Co > Ni > Mg > Al > Mn > Si> Cu > Zn > Fe, while the order of enrichment is P > Ca > Ba > Pb > Sr. The phosphate mineral controls the concentration variation of the ore-forming elements in crusts and causes loss of the main ore-forming elements such as Co and Ni. The phosphatization also affects the abundance of REEs in the crusts. REEs are more abundant and the content of Ce in old crusts is higher than that in young crusts, however, the pattern of REEs and their fractionation characteristics in new and old crusts are not fundamentally changed. A Y-positive anomaly in old crusts has no relationship to the phosphatization.

关键词： phosphatization ore-forming element REE Co-rich crust concentration effect Pacific

Discovery of phosphatized gastrula fossils from the Dou-shantuo Formation,Weng'an,Guizhou Province,China

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Chinese Science Bulletin 2001年第20期46卷 1713-1716页

作者： Yin Chongyu Yue Zhao Gao Linzhi Institute of Geology Chinese Academy of Geological Sciences Beijing China

Globular fossils from Doushantuo phosphorites at the Weng’an area are for the first time identified as a gas-trulation stage of phosphatized embryos. They are got from the fossiliferous remains after acetic acid maceration. The fossils are found together with formerly reported animal resting eggs and embryos of the earlier cleavage stage. The oblate-shaped fossils with the same size as those reported embryos and invaginate at the middle part into the embryos, show the characteristics of the late blastula to the early gas-trula stage of the embryo development. This discovery convinces the existence of animal embryos at Doushantuo age and offers new facts for the studying of the affinity of related fossils, which are still controversial at present.

关键词： Doushantuo Formation phosphorites gastrulation phosphatization resting eggs embryos.