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Dagmar Dietrich - One of the best experts on this subject based on the ideXlab platform.
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PetrifactionS AND WOOD-TEMPLATED CERAMICS: COMPARISONS BETWEEN NATURAL AND ARTIFICIAL SILICIFICATION
IAWA Journal, 2015Co-Authors: Dagmar Dietrich, Mike Viney, Thomas LampkeAbstract:Fascination with petrified wood has stimulated interest in understanding the process of natural Petrifaction. Early attempts of modeling natural Petrifaction in the laboratory have been limited to mimicking incipient permineralization resulting in the creation of silica casts of pore spaces and inner cell walls. Silica lithomorphs produced through artificial silicification provided a possible avenue for studying microstructure of wood. More recently artificial Petrifaction is motivated by the goal of creating advanced ceramic materials for engineering applications. The concept of using wood as a biotemplate has led to the creation of porous ceramics by cell wall replacement. To some extent artificial and natural Petrifaction processes are comparable; although, some of the materials and procedures used in the laboratory are not found in nature. Research focused on the composition and structure of fossil wood from different-aged deposits is compared with research focused on the development of wood-templated porous ceramics. Differences and similarities in the pathways of natural silicification and creation of biomorphous ceramics are discussed. The comparison between artificial and natural silicification highlights the particular significance of the degree to which (de)lignification is needed for silica permeation.
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A microstructure study on silicified wood from the Permian Petrified Forest of Chemnitz
Paläontologische Zeitschrift, 2013Co-Authors: Dagmar Dietrich, Thomas Lampke, Ronny RößlerAbstract:Drei typische Kieselhölzer des 290 Millionen Jahre alten Versteinerten Waldes von Chemnitz (Zeisigwald Tuff-Horizont, Leukersdorf-Formation) wurden hinsichtlich ihrer Mikrostruktur untersucht: Proben des Baumfarns Psaronius sp., des Farnsamers Medullosa stellata , und des Nacktsamers Dadoxylon sp. Mittels Rückstreuelektronen-Abbildungen und Beugungsuntersuchungen im Rasterelektronenmikroskop wird die vorzügliche anatomische Erhaltung des Pflanzengewebes durch Silifizierung und andere Mineralisationen gezeigt. Die Zellwände weisen zumeist Quarz in gut ausgebildeten Kristallen auf, während die eingeschlossenen Zelllumina durch kryptokristalline Siliziumdioxid-Varietäten konserviert wurden. Die unterschiedliche Kristallinität sowie die Anordnung und Größe der Kristallite spiegeln den ursprünglich vorhandenen Aufbau der Zellwand und deren chemische Zusammensetzung im Holzteil wider. Die Ergebnisse werden mit Bezug auf die Zellwandorganisation des Xylems rezenter Pflanzen diskutiert, das aus stark hydrophiler Zellulose und Hemizellulose besteht, die durch hydrophobes Lignin vernetzt sind. Der Einfluss der polaren und unpolaren Holzbestandteile auf die Ausfällung von Silica aus einem wässrigen Sol und auf die Kristallisation ist auffallend. Im Umkehrschluss ermöglichen die vorgestellten Ergebnisse ein vertieftes Verständnis, wie während des Versteinerungsprozesses die organischen Bestandteile silifiziert wurden. Three typical plant taxa from the fossil assemblage of the 290-million-year-old Chemnitz Petrified Forest (Zeisigwald Tuff Horizon, Leukersdorf Formation) were studied with regard to the microstructure of the Petrifactions: samples of the tree fern Psaronius sp., the seed fern Medullosa stellata , and the gymnosperm Dadoxylon sp. The plant’s tissues are anatomically preserved by silica exhibiting different crystalline order and by other mineralisations. Specimens were studied by means of electron backscatter imaging and electron backscatter diffraction in a scanning electron microscope. The cell walls were largely preserved by quartz crystals, the cell lumina by cryptocrystalline silica. The former organisation and chemical composition of the vascular tissue are mirrored by varying grain formation and grain size. Results are discussed in terms of extant xylem cell wall organisation showing highly hydrophilic cellulose and hemicellulose cross-linked by hydrophobic lignin. The effect of polar and non-polar wood components on the precipitation of silica from aqueous solution and on the formation of crystals is convincing, and the reported results provide a better understanding of how silica replaced organic matter during the Petrifaction process.
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A microstructure study on silicified wood from the Permian Petrified Forest of Chemnitz
Paläontologische Zeitschrift, 2013Co-Authors: Dagmar Dietrich, Thomas Lampke, Ronny RößlerAbstract:Three typical plant taxa from the fossil assemblage of the 290-million-year-old Chemnitz Petrified Forest (Zeisigwald Tuff Horizon, Leukersdorf Formation) were studied with regard to the microstructure of the Petrifactions: samples of the tree fern Psaronius sp., the seed fern Medullosa stellata, and the gymnosperm Dadoxylon sp. The plant’s tissues are anatomically preserved by silica exhibiting different crystalline order and by other mineralisations. Specimens were studied by means of electron backscatter imaging and electron backscatter diffraction in a scanning electron microscope. The cell walls were largely preserved by quartz crystals, the cell lumina by cryptocrystalline silica. The former organisation and chemical composition of the vascular tissue are mirrored by varying grain formation and grain size. Results are discussed in terms of extant xylem cell wall organisation showing highly hydrophilic cellulose and hemicellulose cross-linked by hydrophobic lignin. The effect of polar and non-polar wood components on the precipitation of silica from aqueous solution and on the formation of crystals is convincing, and the reported results provide a better understanding of how silica replaced organic matter during the Petrifaction process.
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Analytical X-Ray Microscopy on Psaronius sp. - A Contribution to Permineralization Process Studies
Mikrochimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old Petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-ray microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-ray microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-ray spot diameter suitable with the dimension of the fossil plants.
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Analytical X-Ray Microscopy on Psaronius sp. – A Contribution to Permineralization Process Studies
Microchimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old Petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-ray microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-ray microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-ray spot diameter suitable with the dimension of the fossil plants.
Günter Marx - One of the best experts on this subject based on the ideXlab platform.
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Analytical X-Ray Microscopy on Psaronius sp. - A Contribution to Permineralization Process Studies
Mikrochimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old Petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-ray microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-ray microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-ray spot diameter suitable with the dimension of the fossil plants.
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Analytical X-Ray Microscopy on Psaronius sp. – A Contribution to Permineralization Process Studies
Microchimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old Petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-ray microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-ray microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-ray spot diameter suitable with the dimension of the fossil plants.
George E. Mustoe - One of the best experts on this subject based on the ideXlab platform.
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Wood Petrifaction: A new view of permineralization and replacement
Geosciences (Switzerland), 2017Co-Authors: George E. MustoeAbstract:Petrified wood has traditionally been divided into two categories based on preservation processes: permineralization (where tissues are entombed within a mineral-filled matrix) and replacement (where organic anatomical features have been replicated by inorganic materials). New analytical evidence suggests that for most petrified wood, permineralization and replacement are not independent processes; instead, both processes may occur contemporaneously during diagenesis. Infiltration of mineral-bearing groundwater may initially cause permineralization of cellular tissues, but the wood is undergoing gradual degradation. The degree of anatomical preservation thus depends on the relative rates of mineral precipitation and tissue destruction. Rapid rates of mineralization under relatively mild Eh and pH conditions favor the preservation of organic matter. These conditions appear to be more common for calcium carbonate deposition than for silicification, based on observations of fossil woods from many localities. Because of these preservational complexities, “mineralization” and “mineralized” are more accurate as general descriptive terms than “permineralization” and “permineralized”.
Ronny Rößler - One of the best experts on this subject based on the ideXlab platform.
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A microstructure study on silicified wood from the Permian Petrified Forest of Chemnitz
Paläontologische Zeitschrift, 2013Co-Authors: Dagmar Dietrich, Thomas Lampke, Ronny RößlerAbstract:Drei typische Kieselhölzer des 290 Millionen Jahre alten Versteinerten Waldes von Chemnitz (Zeisigwald Tuff-Horizont, Leukersdorf-Formation) wurden hinsichtlich ihrer Mikrostruktur untersucht: Proben des Baumfarns Psaronius sp., des Farnsamers Medullosa stellata , und des Nacktsamers Dadoxylon sp. Mittels Rückstreuelektronen-Abbildungen und Beugungsuntersuchungen im Rasterelektronenmikroskop wird die vorzügliche anatomische Erhaltung des Pflanzengewebes durch Silifizierung und andere Mineralisationen gezeigt. Die Zellwände weisen zumeist Quarz in gut ausgebildeten Kristallen auf, während die eingeschlossenen Zelllumina durch kryptokristalline Siliziumdioxid-Varietäten konserviert wurden. Die unterschiedliche Kristallinität sowie die Anordnung und Größe der Kristallite spiegeln den ursprünglich vorhandenen Aufbau der Zellwand und deren chemische Zusammensetzung im Holzteil wider. Die Ergebnisse werden mit Bezug auf die Zellwandorganisation des Xylems rezenter Pflanzen diskutiert, das aus stark hydrophiler Zellulose und Hemizellulose besteht, die durch hydrophobes Lignin vernetzt sind. Der Einfluss der polaren und unpolaren Holzbestandteile auf die Ausfällung von Silica aus einem wässrigen Sol und auf die Kristallisation ist auffallend. Im Umkehrschluss ermöglichen die vorgestellten Ergebnisse ein vertieftes Verständnis, wie während des Versteinerungsprozesses die organischen Bestandteile silifiziert wurden. Three typical plant taxa from the fossil assemblage of the 290-million-year-old Chemnitz Petrified Forest (Zeisigwald Tuff Horizon, Leukersdorf Formation) were studied with regard to the microstructure of the Petrifactions: samples of the tree fern Psaronius sp., the seed fern Medullosa stellata , and the gymnosperm Dadoxylon sp. The plant’s tissues are anatomically preserved by silica exhibiting different crystalline order and by other mineralisations. Specimens were studied by means of electron backscatter imaging and electron backscatter diffraction in a scanning electron microscope. The cell walls were largely preserved by quartz crystals, the cell lumina by cryptocrystalline silica. The former organisation and chemical composition of the vascular tissue are mirrored by varying grain formation and grain size. Results are discussed in terms of extant xylem cell wall organisation showing highly hydrophilic cellulose and hemicellulose cross-linked by hydrophobic lignin. The effect of polar and non-polar wood components on the precipitation of silica from aqueous solution and on the formation of crystals is convincing, and the reported results provide a better understanding of how silica replaced organic matter during the Petrifaction process.
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A microstructure study on silicified wood from the Permian Petrified Forest of Chemnitz
Paläontologische Zeitschrift, 2013Co-Authors: Dagmar Dietrich, Thomas Lampke, Ronny RößlerAbstract:Three typical plant taxa from the fossil assemblage of the 290-million-year-old Chemnitz Petrified Forest (Zeisigwald Tuff Horizon, Leukersdorf Formation) were studied with regard to the microstructure of the Petrifactions: samples of the tree fern Psaronius sp., the seed fern Medullosa stellata, and the gymnosperm Dadoxylon sp. The plant’s tissues are anatomically preserved by silica exhibiting different crystalline order and by other mineralisations. Specimens were studied by means of electron backscatter imaging and electron backscatter diffraction in a scanning electron microscope. The cell walls were largely preserved by quartz crystals, the cell lumina by cryptocrystalline silica. The former organisation and chemical composition of the vascular tissue are mirrored by varying grain formation and grain size. Results are discussed in terms of extant xylem cell wall organisation showing highly hydrophilic cellulose and hemicellulose cross-linked by hydrophobic lignin. The effect of polar and non-polar wood components on the precipitation of silica from aqueous solution and on the formation of crystals is convincing, and the reported results provide a better understanding of how silica replaced organic matter during the Petrifaction process.
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Analytical X-Ray Microscopy on Psaronius sp. - A Contribution to Permineralization Process Studies
Mikrochimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old Petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-ray microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-ray microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-ray spot diameter suitable with the dimension of the fossil plants.
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Analytical X-Ray Microscopy on Psaronius sp. – A Contribution to Permineralization Process Studies
Microchimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old Petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-ray microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-ray microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-ray spot diameter suitable with the dimension of the fossil plants.
Thomas Lampke - One of the best experts on this subject based on the ideXlab platform.
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PetrifactionS AND WOOD-TEMPLATED CERAMICS: COMPARISONS BETWEEN NATURAL AND ARTIFICIAL SILICIFICATION
IAWA Journal, 2015Co-Authors: Dagmar Dietrich, Mike Viney, Thomas LampkeAbstract:Fascination with petrified wood has stimulated interest in understanding the process of natural Petrifaction. Early attempts of modeling natural Petrifaction in the laboratory have been limited to mimicking incipient permineralization resulting in the creation of silica casts of pore spaces and inner cell walls. Silica lithomorphs produced through artificial silicification provided a possible avenue for studying microstructure of wood. More recently artificial Petrifaction is motivated by the goal of creating advanced ceramic materials for engineering applications. The concept of using wood as a biotemplate has led to the creation of porous ceramics by cell wall replacement. To some extent artificial and natural Petrifaction processes are comparable; although, some of the materials and procedures used in the laboratory are not found in nature. Research focused on the composition and structure of fossil wood from different-aged deposits is compared with research focused on the development of wood-templated porous ceramics. Differences and similarities in the pathways of natural silicification and creation of biomorphous ceramics are discussed. The comparison between artificial and natural silicification highlights the particular significance of the degree to which (de)lignification is needed for silica permeation.
-
A microstructure study on silicified wood from the Permian Petrified Forest of Chemnitz
Paläontologische Zeitschrift, 2013Co-Authors: Dagmar Dietrich, Thomas Lampke, Ronny RößlerAbstract:Drei typische Kieselhölzer des 290 Millionen Jahre alten Versteinerten Waldes von Chemnitz (Zeisigwald Tuff-Horizont, Leukersdorf-Formation) wurden hinsichtlich ihrer Mikrostruktur untersucht: Proben des Baumfarns Psaronius sp., des Farnsamers Medullosa stellata , und des Nacktsamers Dadoxylon sp. Mittels Rückstreuelektronen-Abbildungen und Beugungsuntersuchungen im Rasterelektronenmikroskop wird die vorzügliche anatomische Erhaltung des Pflanzengewebes durch Silifizierung und andere Mineralisationen gezeigt. Die Zellwände weisen zumeist Quarz in gut ausgebildeten Kristallen auf, während die eingeschlossenen Zelllumina durch kryptokristalline Siliziumdioxid-Varietäten konserviert wurden. Die unterschiedliche Kristallinität sowie die Anordnung und Größe der Kristallite spiegeln den ursprünglich vorhandenen Aufbau der Zellwand und deren chemische Zusammensetzung im Holzteil wider. Die Ergebnisse werden mit Bezug auf die Zellwandorganisation des Xylems rezenter Pflanzen diskutiert, das aus stark hydrophiler Zellulose und Hemizellulose besteht, die durch hydrophobes Lignin vernetzt sind. Der Einfluss der polaren und unpolaren Holzbestandteile auf die Ausfällung von Silica aus einem wässrigen Sol und auf die Kristallisation ist auffallend. Im Umkehrschluss ermöglichen die vorgestellten Ergebnisse ein vertieftes Verständnis, wie während des Versteinerungsprozesses die organischen Bestandteile silifiziert wurden. Three typical plant taxa from the fossil assemblage of the 290-million-year-old Chemnitz Petrified Forest (Zeisigwald Tuff Horizon, Leukersdorf Formation) were studied with regard to the microstructure of the Petrifactions: samples of the tree fern Psaronius sp., the seed fern Medullosa stellata , and the gymnosperm Dadoxylon sp. The plant’s tissues are anatomically preserved by silica exhibiting different crystalline order and by other mineralisations. Specimens were studied by means of electron backscatter imaging and electron backscatter diffraction in a scanning electron microscope. The cell walls were largely preserved by quartz crystals, the cell lumina by cryptocrystalline silica. The former organisation and chemical composition of the vascular tissue are mirrored by varying grain formation and grain size. Results are discussed in terms of extant xylem cell wall organisation showing highly hydrophilic cellulose and hemicellulose cross-linked by hydrophobic lignin. The effect of polar and non-polar wood components on the precipitation of silica from aqueous solution and on the formation of crystals is convincing, and the reported results provide a better understanding of how silica replaced organic matter during the Petrifaction process.
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A microstructure study on silicified wood from the Permian Petrified Forest of Chemnitz
Paläontologische Zeitschrift, 2013Co-Authors: Dagmar Dietrich, Thomas Lampke, Ronny RößlerAbstract:Three typical plant taxa from the fossil assemblage of the 290-million-year-old Chemnitz Petrified Forest (Zeisigwald Tuff Horizon, Leukersdorf Formation) were studied with regard to the microstructure of the Petrifactions: samples of the tree fern Psaronius sp., the seed fern Medullosa stellata, and the gymnosperm Dadoxylon sp. The plant’s tissues are anatomically preserved by silica exhibiting different crystalline order and by other mineralisations. Specimens were studied by means of electron backscatter imaging and electron backscatter diffraction in a scanning electron microscope. The cell walls were largely preserved by quartz crystals, the cell lumina by cryptocrystalline silica. The former organisation and chemical composition of the vascular tissue are mirrored by varying grain formation and grain size. Results are discussed in terms of extant xylem cell wall organisation showing highly hydrophilic cellulose and hemicellulose cross-linked by hydrophobic lignin. The effect of polar and non-polar wood components on the precipitation of silica from aqueous solution and on the formation of crystals is convincing, and the reported results provide a better understanding of how silica replaced organic matter during the Petrifaction process.