博士 / 國立成功大學 / 資源工程學系碩博士班 / 96 / High-resolution transmission electron microscopy (TEM) accompanied with petrographic observation, X-ray diffraction (XRD) and electron probe microanalysis (EPMA) has been used to study the glauconitic pellets occurred in Tertiary sedimentary rocks from Kuohsing and Chungliao areas, central Taiwan; especially from Takeng Formation, Tsukeng Formation, and Shuichangliu Formation, respectively. The glauconitic pellets show two main types in morphology: ovoid pellets and vermicular pellets, with that the vermicular pellets is much well-crystallized than the ovoid pellets. The optical properties show that the ovoid glauconitic pellets consist of microcrystals of phyllosilicates in random orientation. Whereas, the vermicular glauconitic pellets occur like a single crystal. The vermicular glauconitic pellets has cleavages which are approximately perpendicular to the long axis of grain. The XRD results show that the glauconitic pellets contain glauconite, chlorite, and small amount of smectites. The TEM study has shown that the spheroidal pellets consist mainly of packets of glauconite and Fe-riched chlorite, muscovite, biotite. The packet size of glauconite are ranging from tens of Å to hundreds of Å (thickness in perpendicular to basal plane). There are also small amounts of submicroscopic quartz, apatite, and monazite in the pellets. The vermicular pellets consist of glauconite pellets with very little chlorite or no chlorite. The basal planes of glauconite packets are perpendicular approximately to the long axis of the vermicular pellets, whereas the glauconite and chlorite packets generally arrange in random in the spheroidal pellets. The EPMA results show vermicular glauconitic pellets has more K and Fe contents than the spheroidal or ovoid glauconitic pellets, and thus imply that spheroidal or ovoid glauconitic pellets have more glauconite/smectite mixed layers than vermicular glauconitic pellets. Based on the morphology, mineral constituents, mineral composition, and submicroscopic textures, it appears that the ovoid and vermicular glauconitic pellets have formed from precursors of faecal pellets, via glauconition and diagenesis.
| Identifer | oai:union.ndltd.org:TW/096NCKU5397063 |
| Date | January 2008 |
| Creators | Shyun-sheng Chang, 張郇生 |
| Contributors | Yung-hui Shen, Jui-Lin Chang, 申永輝, 張瑞麟 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 74 |
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