Skripsi

ANALISIS ARUS PURBA FORMASI SIMPANGAUR PADA ORIENTASI FOSIL DAN IMBRIKASI KONGLOMERAT DAERAH PAGAR DAN SEKITARNYA, KABUPATEN SELUMA, BENGKULU

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Penilaian

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This research is focused on the Simpangaur Formation located in Pagar Village and its surroundings, Seluma Regency, Bengkulu which discusses paleocurrents during the deposition of the Simpangaur Formation. To find out the geological conditions and the character of paleocurrents formed at the observation location, a study is needed including geological mapping activities and collecting data on the direction of currents in fossil mollusks and fragment imbrication. Field observations were made on sandstones and conglomerates of the Simpangaur Formation that have measurable proxies. The rocks found are carbonate and non-carbonate caused by transgression and regression phases that affect the character of the rocks formed. Research on the direction of paleocurrents will also produce the location of the depositional environment, because these two things are interconnected because the depositional environment can form a typical paleocurrent. In analyzing the data obtained from the reading of the current direction at each observation location, it is necessary to process it with statistical methods. The statistical method used is simple statistics by calculating the average of the results of paleocurrent measurements. The number of observation points where paleocurrent direction measurements were made was 18 data which were then presented in the form of rose diagrams and vector diagrams. Processing and presentation of existing data is done using GeoRose and Dips software. Stratigraphically, the study area is divided into four rock units, namely the Sandstone Unit, and the Conglomerate Unit. In its formation, there were four changes in the orientation of ancient currents in each rock unit, in the Sandstone Unit forming a unimodal pattern that ranges from N 228° E - N 291° E, then changes in the Conglomerate Unit forming a unimodal pattern ranging from N 106° E - N 175° E. Followed by changes in the Sandstone Unit forming a bimodal pattern that ranges from N 211° E - N 247° E and N 256° E - N 279° E and the last change in the Conglomerate Unit forming a unimodal pattern that ranges from N 094° E - N 216° E. The unimodal orientation of the shells indicates a shallow marine depositional environment due to the influence of longshore currents. While the orientation of the unimodal pattern in the imbrication of fragments indicates strong currents in the river environment. The sandstone unit formed has a sandstone lithology that gradually coarsens upwards and the abundant fossil content gradually disappears the higher the layer. In this unit, Conus sauridens, Saxicava rugosa, and Turritella sp. were found, which generally characterize shallow to transitional marine depositional sites. The depositional environment of the study site has two locations, this is because the two lithologies formed have much different characteristics so as to form facies interfingering. Sandstone was deposited in shallow marine and conglomerate in braided channel.

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Availability

Inventory Code	Barcode	Call Number	Location	Status
2407006250	T159181	T1591812024	Central Library (REFERENCE)	Available but not for loan - Not for Loan

Detail Information

Series Title

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Call Number

T1591812024

Publisher

Indralaya : Prodi Teknik Geologi, Fakultas Teknik Universitas Sriwijaya., 2024

Collation

xiii, 94 hlm.; ilus.; 29 cm

Language

Indonesia

ISBN/ISSN

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Classification

551.470 7

Content Type

Text

Media Type

unmediated

Carrier Type

-

Edition

-

Subject(s)

Prodi Teknik Geologi
Sedimentologi

Specific Detail Info

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Statement of Responsibility

TUTI

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