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Thailand’s fossil forests hold international importance for a variety of reasons. The operation of a gravel mine exposed sediment layers containing petrified wood logs, highlighting the critical need to preserve these unique artifacts and address associated environmental concerns. A comprehensive lithological study was conducted on pit walls. Employing 2D ERT and 2D IP methods, geology was classified from the ground surface and validated through drilling logs. The sediment and deposit categorization at gravel pit sites revealed four distinct units: Unit I, conglomeratic sand, exhibiting characteristics typical of fluvial deposits; Unit II, indicating alluvial fan deposition with lenticular gravel and sand highlighting the presence of petrified wood logs; Unit III, massive gravel suggesting channel deposits of an alluvial fan with an abundance of petrified wood; and Unit IV, red soil (collapsible soil). The 2D ERT method successfully examined the boundary sediment layer and mudstone, though classification of sediment units was not achieved. Quaternary terrace sediments underlie the mudstone, identified as an aquitard that effectively prevents surface contamination of the groundwater aquifer. The data from this study serves as fundamental geological information, providing remarkable and essential evidence for the preservation of petrified wood and the safeguarding of the groundwater environment. This site is particularly an outstanding geosite. This research contributes to our understanding of depositional environments and geological processes and proposes conservation strategies. [ABSTRACT FROM AUTHOR]

Worldwide, silicified woods are found in many geological formations. Significantly, the organic materials of wood are no longer dominant; almost all wood fossils have been mineralized into inorganic silica materials. These unique geological processes must be understood to develop better understanding on organic material fossilization, particularly in the micron scale. Therefore, our aim was to characterize the composition of silicified wood using comprehensive microanalysis. The methods utilized were XRF, ICP-MS, XRD, FTIR, and FE-EPMA. Specimens are from Jasinga, West Java, Indonesia. The results showed that wood silicification was controlled by the infiltration of silica from the host rock into the spaces of the wood structure. In Jasinga, they are controlled by Pliocene tuffaceous sedimentary rocks. The ratio of silica phases revealed a trend in the degree of silicification. Besides silica, the distribution of trace elements also demonstrates the geochemical interaction between the wood fossil and host rock. Wood fossils are affected by the gradual replacement of organic carbon-based materials with silica through silicification. Silica enrichment occurs in the internal of wood, facilitates permineralization and recrystallization. Silica replaces organic material and preserves the wood structures. The microanalytical approach provides comprehensive perspectives on wood petrification, leads to better insights for paleontological studies. [ABSTRACT FROM AUTHOR]

The research on chemical composition and microstructure of petrified wood has scarcely been reported in China and abroad, and the study about micro-mechanical characteristics has not been carried out. In this paper, the domestic and foreign research progress was summarized at the same time, and the crystal orientation in the cell wall of Pinus tabulaeformis petrified wood was measured according to the method of wood's MFA using x-ray diffraction techniques, while micro-mechanical characteristics were further studied using nanoindentation. The results showed that silica crystals in petrified wood cell wall were arranged from 22.19 to 25.98 ° in accordance with the micro fibril angle. The micro-mechanical characteristics of silica crystals in different locations inside the petrified wood were different; the modulus and hardness of silica crystals in the lumen region were 89.86 and 9.33 GPa, but 63.07 and 5.20 GPa in the cell wall region. The difference of hardness and modulus of two parts regional were 44.34 and 27.30 %, respectively; this result was supported by A. Kuczumow's study, which showed the variability of the secondary electron signal of Si could be even over 30 %, the easiest way to explain it was by claiming that the porosity is much increased. [ABSTRACT FROM AUTHOR]

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Country-scale geological events of Neogene and Quaternary age are called neotectonism and so this is known as the neotectonic period in Turkey, where it was responsible for initiating and molding the present-day geomorphology of Anatolia. The neotectonism of the northwestern Anatolia (=western Pontides) are mainly represented by volcanic rocks called the Galatian Volcanic Complex (GVC) which consists of a series of andesites, basalts, and their pyroclastics. Rock sequences of the GVC indicate that volcanism took place abundantly in early and middle Miocene times as three separate phases intercalated by long-term fluviolacustrine environmental conditions. Therefore, the GVC consists of not only volcanics but also volcano sedimentary and pure sedimentary units. It blankets the various rock units from late Palaeozoic to Oligocene in age (=the Anatolian continent, substratum). As a result, rock units of the substratum here and the GVC together represent the whole record of the geological past of the western Pontides. Meantime, this region has been watched daily by thousands of travelers due to presence of highways, bringing a very colorful landscape with many erosional features to the public's attention. In 2011, a 2,000 km part of the Galatian Volcanic Complex was registered as a geoconservation area called the Kızılcahamam-Çamlıdere Geopark Project by the authorized Turkish institutions. The general geology of the area and three geosites are introduced here. These geosites include (a) a petrified forest, (b) columnar basalts, and (c) a lacustrine sequence with leaf, fish, and insect fossils. These three geosites are the best representatives for demonstrating the Miocene environmental circumstances and sedimentary responses to a long-term, large-scale volcanism during the neotectonic period. [ABSTRACT FROM AUTHOR]

The investigation of the interesting collection of the petrified wood from Bondyrz, Roztocze, south-eastern Poland, has been continued. Two kinds of microprobes such as electron microprobe from the Catholic University of Lublin and synchrotron-based X-ray microprobe from LURE, Orsay, were applied to detect the elements associated with the main component – silica and their spatial distribution and interrelations. The distribution of carbon in the petrified material has been established, which is important since that element is the main remains from the history of the trees. The carbon distribution was characteristic – it concentrated on a place of primordial dark wood. The distribution patterns of the other elements were either similar to that of carbon (Cu, Pb) or they concentrated in separate inclusions (Fe, Al, K, Na, Ca). The replicating mode of the original wood pattern in silica and carbon-containing material was explained. Some indications about the composition of the primordial petrifying solution, the rate of the petrifaction process and the recent coloration of the sample could be concluded from the compositional patterns of silica. The boundary between totally and partially petrified zones could be well observed. [ABSTRACT FROM AUTHOR]