碩士 / 國立中山大學 / 海洋資源研究所 / 86 / 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. The glauconitic pellets mainly occur in siltstones and mudstones that contain abundant shell fossils and trace fossils. The glauconitic pellets show two main types in morphology: spheroidal or ovoid pellets and vermicular pellets, with that the former is much abundant than the latter. The optical properties show that the spheroidal or 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 showthat 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 angstrom to hundreds of angstrom (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 spheroidal and vermicular glauconitic pellets have formed from precursors of faecal pellets, via glauconition and diagenesis.-1 -aA study of mineralogy and submicrostructures of glauconite pellets in Tertiary sedimentary rocks from central Taiwan
| Identifer | oai:union.ndltd.org:TW/086NSYSU277004 |
| Date | January 1998 |
| Creators | KU,CHING TE, 辜清德 |
| Contributors | Y. H. SHAU, 蕭炎宏 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 2 |
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