Abstract- Two fossil wood were discovered from  Sindangsari Village, Sajira District, Lebak Regency, Banten Province, Indonesia. They were preserved within tuffaceous rocks of the Genteng Formation in Early Pliocene age in littoral to terrestrial environment deposition. To identify mineral composition of the silicified wood, XRD analyser method was applied. Result of XRD analyses shows that both of fossil wood are Dryobalanoxylon sp. consist of quartz mineral with d value is 3.358 Å and 3.350 Å Keywords : Dryobalanoxylon, Early Pliocene, Genteng Formation, Quartz

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Indonesia is a country which has plants species diversity. The form of ancient plants that grew in the past are recorded as fossil woods. Several fossil woods from regions in Indonesia were collected and became exhibition collections at the Bandung Geological Museum. These fossil woods on display requires biology identity to provide more information to visitors. Identification of species of fossil woods were carried out based on the anatomical features on the smoothed cross-section. Observations were carried out by a loop hand (a magnification of 10 times and a digital loop (with a magnification of 16 times). The fossil woods anatomy features observed included vessel cells, parenchyma cells, rays cells, and the presence of resin channels. The fossil specimen which had unclear anatomy features compared by detailed description of wood anatomy available at the library and collections of wood samples owned by the Xylarium Bogoriense. The fossil woods species are Canarioxylon sp., Terminalioxylon sp., Anisopteroxylon sp., Dipterocarpoxylon sp., Dryobalanoxylon sp., Hopenium/Hopeoxylon sp., Shoreoxylon sp., Kompassioxylon sp., and Xanthophyllum sp. The mostly fossil woods species resvectively belonging to the Dipterocarpaceae, Combretaceae, Polygalaceae, Burseraceae, and Leguminosae. The fossil woods member of Dipterocarpaceae family are conspicuously characterized with the presence of resin canals.

Gorontalo, one of the provinces in Indonesia, has not been widely known for its potential of wood fossil. The anatomical structures observation and the age estimation were conducted on two specimens of wood fossils buried in Tohupo Village, Bongomeme District, Gorontalo. The anatomical features of wood fossils were observed through thin slices of the cross, radial, and tangential sections using a Carl Zeiss-Axio Imager-A1m microscope. The description of anatomical features referred to the IAWA (International Association of Wood Anatomists) list of microscopic features for hardwood identification. The age estimation of the wood fossils was based on Geological Map (scale 1: 100.000) of the Tilamuta sheet, Sulawesi. Based on anatomical structures observation, the species of wood fossils were identified as Hopenium sp. (merawan/hopea) and Shoreoxylon sp. (balau). The estimated age of wood fossils was 3.6 to 1.8 million years before the present (BP) (between the late Pliocene and Early Plistocene periods).

Merangin is a region in Jambi province, Indonesia, which well-known for its geodiversity. As part of geodiversity, fossil woods play an important role in reconstructing the ancient trees during geological history. Since the study on fossil wood origin Merangin Regency, Jambi, is still limited, this study was conducted to determine fossil wood identity through anatomical features observation and estimate the age of fossil wood samples through geological analysis. The anatomical characteristics were observed using a light microscope to identify the botanical identity of the discovered fossil wood samples. The description of anatomical features refered to the IAWA list of microscopic features for hardwood identification. The result showed that all fossil woods had similarities with the modern wood from the Dipterocarpaceae family, namely Dryobalanoxylon sp. (Kamper), Hopenium sp. (Merawan/Hopea), Shoreoxylon sp. (Meranti), and Cotylelobioxylon sp. (Giam/Resak). These fossil woods were found in different estimated geological age namely Late Permian/Perem age (254-252 million years old), Late Miocene age (7.24-5.33 million years old); Late Pliocene to Early Pleistocene age (3.60-2.58 million years old); and Holocene age (11,700 years old - present). Another approach by using Global Mapper 11 resulted that all the fossil woods were estimated grown in Permian age (290 - 250 million years).