Modern Environmental Science and Engineering (ISSN 2333-2581) October 2016, Volume 2, No. 10, pp. 701-707 Doi: 10.15341/mese(2333-2581)/10.02.2016/008 Academic Star Publishing Company, 2016 www.academicstar.us Preliminary Research: Feature of Cross Section, Hardness, and Specific Gravity Some Petrified Wood from Loa Janan, Kutai Kertanegara, East Kalimantan Nani Husien, Agus Sulistyo Budi, and Gandi Laboratory of Information and Woody Plant Biology, Forestry Faculty, Mulawarman University, Indonesia Abstract: The aim of this research is to identify some petrified wood discovered in Loa Janan district of Kutai Kertanegara East Borneo, for anatomical feature in the cross section, the hardness and the specific gravity as well. It was hypothesized that the petrified woods which were discovered would be endemic hardwood species from East Borneo. Six specimens with different size were taken and grinded with different grit (16 to 60). A binocular microscope was used to observe pattern of pores, rays, including resin ducts. Digital balance and measuring glass was used to determine the specific gravity, while selector diamond was used to determine hardness. Reference identifying was used to identify the wood species or genus. Result showed that all specimens were macroscopically identified as Fossil of hardwood, they were characterized by the existence of growth ring, pores, and rays. Most solitary pores grouping filled with mineral deposits were apparent in all of fossil woods. The diversity of color line was probably based on its formed minerals. The hardness of specimens were between 3 to 6 mosh, and were based on the color. The specific gravity of specimens were between 1,715 g/ml to 6,050 g/ml. The Important thing, that based on identification result, the biggest petrified wood which discovered in Loa Janan district of Kutai Kertanegara is most likely species of cf.Leptospermum family Myrsinaceae. Key words: petrified wood, specific gravity, hardness, eusideroxylonzwageri , cf. Leptospermum Indonesia came from the Miocene to Pliocene that is 25 1. Introduction million years BP (Before Present) to 2 million years BP Wood fossil is petrified wood where all the organic [2]. Research on the fossil wood is included in the materials have been replaced by minerals (silica and scope of science of paleobotany. Paleobotany is the quartz type), the wooden structure is still maintained. study of plant fossils. Studies in the field of Wood fossilization process starts from the ingress of paleobotany include aspects of plant fossils, water containing minerals into the cells lining the trees reconstruction taxa, and the history of plant evolution decompose lignin and cellulose so that it becomes a in the world. To understand well about paleobotany, stone. The formation process of wood fossil is similar sciences of geology, anatomy and taxonomy is required. to the formation of fossils of other materials, which is By studying paleobotany we know the botanical due to be chemically permineralization and physical identity of a fossil (anatomy), determine the age of process through a very long process [1, 2]. Fossil wood fossils (geology), and to reconstruct the history of the has a priceless historical value because it could be a spread and extinction of certain plant taxa living proof of a certain tree species in prehistoric times. (fitogeografi). Wood fossil has been found in many Some sources reported that fossil wood found in places in Indonesia, West Java (Ciampea, Jasinga, Leuwiliang, Banten, Sukabumi and Tasikmalaya), Corresponding author: Nani Husien, Master of Science, Central Java (Banjarnegara and the border area Engineer, research areas/interests: wood biology, wood anatomy. E-mail: [email protected]. between Sragen and Karanganyar), East Java (Pacitan), 702 Preliminary Research: Feature of Cross Section, Hardness, and Specific Gravity Some Petrified Wood from Loa Janan, Kutai Kertanegara, East Kalimantan Kalimantan, Jambi, and Flores Island. Lattest internationally. Up to now, petrified wood in Indonesia information also reported many fossils was found in the is still used as a high-value commodity, and if this area of KHDTK Labanan, Berau, East Kalimantan by situation continuous, so the availability of petrified the researchers team from the Research Institute wood could decrease and eventually could extinct. Dipterocarps Samarinda [3]. In addition, it is informed, Andianto et al. (2010) [2], identified the fossil wood that the discovery of fossil wood in traditional house from Kali Cemoro which located on the border of Laitarung Village, Central Sumba was considered as a Sragen and Karanganyar, Central Java. Most of wood cultural keystone species. For other areas there may be fossil found had been petrified but not all part of the found some, but detailed information has not been specimen fossiled. The petrified wood was identified as known. More than three decades ago, wood fossils a species of rengas burung (Gluta wallichii have been excavated but until now it is only used as a Hook.f.DingHou), family Anacardiaceae (Fig. 2). trade commodity, both domestically and Fig. 1 Some petrified woods ready to be traded in (Samarinda city) East Borneo. Fig. 2 Petrified wood of rengas burungand its anatomical structure [1]. Dewi et al. (2012) [4] examined the fossil wood The fossil was found in the formation of volcanic from Wae Wuul Nature Reserve, Flores island. The rock at the tertiary period and lived during the middle fossil was identified as the genus of Shorea periode of Miocene, about 19 million years BP. The (Dipterocarpaceae). The differences in characteristics discovery of Shoreoxylon fossil was surprising because with other fossil Shorea was used to name the fossil, previous record never stated that Shorea has a namely Shoreoxylon floresiensis (Fig. 3). distribution area in Nusa Tenggara and Flores. Whitmore et al. (1989) explained that species of Preliminary Research: Feature of Cross Section, Hardness, and Specific Gravity Some Petrified Wood 703 from Loa Janan, Kutai Kertanegara, East Kalimantan Dipterocarpaceae in Nusa Tenggara are Dipterocarpus tertiary period until the quarter. The volcanic activity is hasseltii and Dipterocarpus retusus. Shoreoxylon evidenced by its rock formations which are volcanic fossils were previously only found in Sumatra, Borneo, rock formations. Macdonald (1972) states that the and Java Island. This indicates that in ancient times, volcano is an area or openings area where the thick those regions were united to the island of Flores. The rock incandescent or gas, both out from inside earth to extinction of species Shorea today in Nusa Tenggara the surface and then piles the rock material around the probably was caused by the volcanic activity of the hole then forms a hill or mountain. Fig. 3 Wood Fossils from Floresandtheir anatomical features [3]. Meanwhile the surprising discovery of petrified reason for the author to do this research, because the wood, was the discovery of the longest and the largest species scientifically this largest fossil wood so far has fossil wood that never been found before in Kalimantan, not been studied, besides, in this research, some other namely fossil wood with 28.5 meters in length and 1.40 specimen of petrified wood found adjacent to the meters in diameter, which found in the region Loa largest fossil site were taken to be analyzed. Janan District of Kutai Kertanegara, the size of this 2. Materials and Methods fossil was suppose could be bigger, because not all parts of the fossil are removed from the ground. Specimens were taken from Purwajaya Village, Loa According to its inventor Mr. Gandi (Interview, 2015), Janan, District of Kutai Kartanegara, located at 5th he discovered the largest fossil actually in year 2001, Kilometers between Balikpapan and Samarinda City, because of its extremely size and the tranding topic the location was at the ridge and close from the about “fossil stone” at that time was not yet to be trend, residential areas. Material used was six specimen of so that, this fossil newly exposed in the year 2015. The petrified wood. Two of the materials (Specimens No.1 fossil wood which is discovered in Loa Janan up to and No. 2) were taken from the part of the largest now was not known yet its species, therefore it also the petrified wood (Fig. 4) and also four other specimens 704 Preliminary Research: Feature of Cross Section, Hardness, and Specific Gravity Some Petrified Wood from Loa Janan, Kutai Kertanegara, East Kalimantan were taken from adjacent place. All specimens are in and resin ducts. Diamond selector is also used to irregular form with each dimension as shown in Fig. 5. determine the hardness. Digital balance, becker glass The equipment to polish the petrified wood was hand and measuring glass used to determine the specific grinders with different grits from very coarse (grade 16) gravity. Reference IAWA standard (1989) [5] and to medium (grade 60), a 20x binocular microscope ATLAS of Hardwood (1991) were used to identify the XTD3C was used to observe the pattern of pores, rays species or genus of the specimens. Fig. 4 The Petrified wood (28.5 m in length, 1.0 m in diameter). Picture was taken in 2001 (left) and in 2015 (right), here showed both side of the fossil supported by steel to avoid cracking. Fig. 5 Materials with difference size. 2.1 Procedure increased to a finer grain of sander for polishing. Each piece of petrified wood took approximately 10-15 The petrified wood was first cleaned with water, minutes to Polish, the polishing steps were performed then polished using hand sanders with different in the workshop in Samarinda. After polishing, then the coarseness, beginning with the most coarse and Preliminary Research: Feature of Cross Section, Hardness, and Specific Gravity Some Petrified Wood 705 from Loa Janan, Kutai Kertanegara, East Kalimantan hardness of petrified wood was determined manually and its formation’s era is unknown yet, and it is using a diamond tester at the four different zone on the estimated millions years in age.