| Summary: | The study area was located in Gunung Temas, Talang Village, Bayat Sub-district,
Central Java Province, which was a part of Jiwo Hills. There are only four location in
Jiwo Hills which has a limestone outcrop, there are Gunung Tugu, Gunung Lanang,
Gunung Kapak and one of it is Gunung Temas. Gunung Temas is a recently opened
limestone query, so that the rock bedding at this location was exposed. The geological
data is feared to be lost because of the intensive querying in this area. This study was
conducted because there has not been detailed discussion about lithostratigraphy and
sedimentation dynamics at this area. This study was performed using petrographic
incisions and foraminifera fossils to know the dynamics of sedimentation and the age
in the study area. From this analysis, this area has 5 Facies rocks, there are Facies A
(interbeded carbonaceous micritic-sandstone) Facies B (intercalation foraminiferal
grainstone, foraminiferal packstone, foraminiferal wackstone), Facies C (intercalation
of foraminiferal grainstone, foraminiferal packstone with sandstone), Facies D
(interbeded packstone), Facies E (packstone with slump structure). The fifth facies,
generate 2 facies association, i.e facies association 1 consists of facies A and facies C
which is showing the depositional environment on the open sea shelf facies with
turbidity current of depositional mechanism. Facies association 2 consists of facies B,
D and E, it deposited on carbonate basin facies environment. The depositional
mechanisms are turbidity and gravitational, which produce good bedding rocks. The
degrees of slope in this area allow the occurrence of sedimentation movement in the
deep sea which produced slump structure in the rock beds. Based on the paleontological
analysis, this study area just have an age zone, that is N17 zone. The zone characterized
the lithology of Gunung Temas was deposited on Late Miocene (N17). Based on the results, it can be conclude, sea level rise twice time and drop once time when sediments
deposited.
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