Mollusk paleontology research in Indonesia so far has not been widely utilized in various kinds of applications, especially in the geology. Although mollusk in Java is very rich, the study of correlation between mollu...Mollusk paleontology research in Indonesia so far has not been widely utilized in various kinds of applications, especially in the geology. Although mollusk in Java is very rich, the study of correlation between mollusk appearances with geological condition is rare. This study aimed to determine Turritellidae base on morphological observations (qualitative) and quantitative (biometric method). The ultimate goal is to find out the relationship between of biometrical aspect of Turritellidae with geological development especially of chronological conditions. Stratigraphic analysis and sampling have done at five location of field survey. Site selection was based on the type locality of mollusk biostratigraphic unit arrange by Martin (1919) [1] and Oostingh (1938) [2]. The scattered analysis shows two large distribution of consistent groups based on shell size and geochronological aspect. Biometrical aspect of Turritellidae is reflection of the chronological aspect in West Java. Small size was appearance in Upper Miocene to Lower Pliocene and large shell in Pliocene to Pleistocene.展开更多
Age determination of paleotsunami sediment from Lombok Island, Indonesia, and surrounding area has been carried out using the 210 Pb method in BATAN Jakarta. The basic theory of this method assumes that weathering of ...Age determination of paleotsunami sediment from Lombok Island, Indonesia, and surrounding area has been carried out using the 210 Pb method in BATAN Jakarta. The basic theory of this method assumes that weathering of sediments, including paleotsunami sediments, will result in 210 Pb enrichment. The principle of this method is to calculate 210 Pb contents accumulation in a particular sedimentation interval from the surface to the deeper buried sediments. The results are then converted into age or depositional time in years ago unit. The dating results from the paleotsunami sediments of the Gawah Pudak（S8°46’2.91’’, E115°56’34.23’’） and Gili Trawangan areas（S8°21’1.38’’, E116°2’36.6’’） indicate the Gawah Pudak sediments were deposited 37 years ago（c. in 1977）and 22 years ago（c. in 1992）. Three paleotsunami sediments from Gili Trawangan were deposited 149 years ago（c. in 1865）, 117 years ago（c. in 1897） and 42 years ago（c. in 1972）. These results are then compared to the available Indonesian earthquake catalogue data. This study reveals that paleotsunami sediments around Lombok Islands, from older to younger, were caused by the 1857 earthquake（epicentre in Bali Sea; M7; S8°00’09.45’’,E115°29’56.41’’）, 1897 earthquake（epicentre in Flores Sea;M5.5; S6°47’59.62’’, E120°48’03.5’’ or Sulu Sea earthquake; M8.5; 70 km NW of Basilan Island）, the 1975 earthquake（Nusa Tenggara; S10°6’16.61’’, E123°48’09.39’’）, 1977 earthquake（in Waingapu, Sumba; M8.0;S11°5’39.34’’, E118°27’50.86’’） and the 1992 earthquake（Flores; M7.8; S8°28’52.11’’, E121°53’44.3’’）.展开更多
文摘Mollusk paleontology research in Indonesia so far has not been widely utilized in various kinds of applications, especially in the geology. Although mollusk in Java is very rich, the study of correlation between mollusk appearances with geological condition is rare. This study aimed to determine Turritellidae base on morphological observations (qualitative) and quantitative (biometric method). The ultimate goal is to find out the relationship between of biometrical aspect of Turritellidae with geological development especially of chronological conditions. Stratigraphic analysis and sampling have done at five location of field survey. Site selection was based on the type locality of mollusk biostratigraphic unit arrange by Martin (1919) [1] and Oostingh (1938) [2]. The scattered analysis shows two large distribution of consistent groups based on shell size and geochronological aspect. Biometrical aspect of Turritellidae is reflection of the chronological aspect in West Java. Small size was appearance in Upper Miocene to Lower Pliocene and large shell in Pliocene to Pleistocene.
文摘Age determination of paleotsunami sediment from Lombok Island, Indonesia, and surrounding area has been carried out using the 210 Pb method in BATAN Jakarta. The basic theory of this method assumes that weathering of sediments, including paleotsunami sediments, will result in 210 Pb enrichment. The principle of this method is to calculate 210 Pb contents accumulation in a particular sedimentation interval from the surface to the deeper buried sediments. The results are then converted into age or depositional time in years ago unit. The dating results from the paleotsunami sediments of the Gawah Pudak（S8°46’2.91’’, E115°56’34.23’’） and Gili Trawangan areas（S8°21’1.38’’, E116°2’36.6’’） indicate the Gawah Pudak sediments were deposited 37 years ago（c. in 1977）and 22 years ago（c. in 1992）. Three paleotsunami sediments from Gili Trawangan were deposited 149 years ago（c. in 1865）, 117 years ago（c. in 1897） and 42 years ago（c. in 1972）. These results are then compared to the available Indonesian earthquake catalogue data. This study reveals that paleotsunami sediments around Lombok Islands, from older to younger, were caused by the 1857 earthquake（epicentre in Bali Sea; M7; S8°00’09.45’’,E115°29’56.41’’）, 1897 earthquake（epicentre in Flores Sea;M5.5; S6°47’59.62’’, E120°48’03.5’’ or Sulu Sea earthquake; M8.5; 70 km NW of Basilan Island）, the 1975 earthquake（Nusa Tenggara; S10°6’16.61’’, E123°48’09.39’’）, 1977 earthquake（in Waingapu, Sumba; M8.0;S11°5’39.34’’, E118°27’50.86’’） and the 1992 earthquake（Flores; M7.8; S8°28’52.11’’, E121°53’44.3’’）.
