Herman Moechtar
Pusat Survei Geologi, Jln. Diponegoro No. 57, Bandung

Published : 17 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 17 Documents
Search

SEDIMENTOLOGI DAN AKUMULASI KASITERIT PADA ENDAPAN ALUVIUM SEPANJANG AIR INAS HINGGA LAUT LEPAS PANTAI TANJUNG KUBU (TOBOALI), BANGKA SELATAN Moechtar, Herman; Hidayat, S.
Jurnal Geologi dan Sumberdaya Mineral Vol 20, No 2 (2010): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (313.275 KB)

Abstract

Placer cassiterite deposits of Air Inas suggest that the deposits consist of mass flows of coarse grains (A1), mass flows of fine grains (A2), offshores (B.1), nearshores (B2), fluvial (B3), Recent deposits of nearshores (C1), and flood basin deposits (C2). The research was based on analizing sedimentology and stratigraphy of eleven boreholes available along North to South traverse. Depth of bore hole varied from 1.60 to 12.20 at elevation of + 25,00 to – 7,20 m of sea level. Based on a series of sedimentary environment correlation, alluvial deposits can be divided into three sedimentary intervals (A,B and C). Each interval is characterized by environmental changes controlled by transgression and regression as well as climatic changes. Referring to cassiterite genesis there are three phenomena namely chemical and physical weatherings, transgression effect and climate changesKeywords: placer deposits, sediment, stratigraphy
GEOLOGI KUARTER DATARAN PANTAI BREBES DAN SEKITARNYA, JAWA TENGAH: Respon Terhadap Peta Geologi Kuarter dan Implikasinya Terhadap Iinformasi Kondisi Geologi Holosen Mulyana, Herman; Basri, T. Chairil; Moechtar, Herman
Jurnal Geologi dan Sumberdaya Mineral Vol 20, No 1 (2010): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (191.314 KB)

Abstract

A study on Quaternary deposits in the coastal-plain of Brebes and surrounding area, Central Java, revealed eight depositional environments. They are: tidal flat (Tf), shallow marine (Sm), floodbasin (Fb), floodplain (Fb), paleochannel (Cp), Resent channel (Cr), mangrove swamp (MgS), and beach sand (B). Based on the correlation of the lateral and vertical variation of the depositional environment, tectonic activities and sea level changes were recognized. During the depositional processes, the activity of tectonic by thrust were recorded as the main factor controling global sea level fluctuation of Holocene. The result of this research is an input for the Quaternary geology study and its implications on Holocene geology conditions which is based on the Quaternary geologic mapping. The study was based on the Quaternary geologic mapping with 1:50,000 scales including an analysis of sedimentology and stratigraphy of sixty boreholes information from the coastal plain of Brebes and surrounding areas.Keywords: Quaternary geologic mapping, Holocene, coastal plain
SEDIMENTOLOGI DAN STRATIGRAFI ALUVIUM BAWAH PERMUKAAN DI PESISIR CIREBON DAN SEKITARNYA Hidayat, Suyatman; Mulyana, Herman; Moechtar, Herman; Subiyanto, Subiyanto
Jurnal Geologi dan Sumberdaya Mineral Vol 19, No 4 (2009): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1023.323 KB)

Abstract

This study was based on sedimentological analyses of seven boreholes located along the NW to SE traverse, approximately parallel to coastal line of Cirebon. The penetration of the bore head varies from 8 to 13 m. Holocene subsurface of alluvial deposits can be divided into seven environment systems, consisting of Gintung Formation and deposits of offshore, nearshore, beach sand, swamp, channel river, and floodplain. Based on stratigraphic aspects, the succession of that sediments can be divided into three sedimentary intervals (IP I-III). Each interval is typically for environment changes which is controlled by changes of sea level, such as high sea level (IP I), sea level falling (IP II), and low sea level (IP III). The Quaternary dynamics related to environment changes and changes of basin fill were influenced by universal of climatic circulation, regional tectonic, and local of sea level changes. Keywords: Aluvium deposits, sea level, tectonic, climate
FASIES DAN PERUBAHAN LINGKUNGAN PENGENDAPAN KUARTER DI DAERAH LABUHAN (BELAWAN), SUMATERA UTARA Mulyana, Herman; Moechtar, Herman
Jurnal Geologi dan Sumberdaya Mineral Vol 18, No 1 (2008): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (596.877 KB)

Abstract

The Quaternary deposits in the Labuhan, Belawan, North Sumatera, have been studied. These deposits have been correlated, using sections on 1:100 scale.  From the correlation of thirteen boring logs, the Quaternary sediments can be divided into facies: (a) marine, (b) beach, (c) marsh, (d) floodbasin, and (e) fluvial channels. Furthermore, the Quaternary sediment consists of 4 (four) depositional cycles namely interval A, B, C, and D.The stratigraphic succession of Quaternary and basin fill in the studied area were influenced by global events. Changes in climatological conditions between sub-humid to optimum into subhumid to dry are the effect from Milankovitch cycles; and sea-level fluctuations from high sea-level into maximum to low sea-level were correlated to global changes of sea-level. Keywords: sedimentary environment, climate, sea-level, global
KARAKTER WILAYAH GENANGAN LAKUSTRIN HOLOSEN BERDASARKAN ASPEK SEDIMENTOLOGI DAN STRATIGRAFI ENDAPAN RAWA DAN UNDAK SUNGAI (Studi Kasus Geologi Kuarter Daerah Air Molek dan Sekitarnya, Kab. Singingi dan Kab. Indragiri Hulu, Provinsi Riau) Hidayat, Suyatman; Basri, C; Subiyanto, Subiyanto; Mulyana, Herman; Moechtar, Herman
Jurnal Geologi dan Sumberdaya Mineral Vol 19, No 5 (2009): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (528.756 KB)

Abstract

This study was based on analyses of sedimentology and stratigraphy of nine sediment samples obtained from shallow boreholes. The boring was done of A - B traverse, southwest – northeast direction around Indragiri river, south of Rengat. The study was focus on river channel and lauctrin deposits under the swamp sediments and river terraces as the resent of penetration of the bore head varies from 3.80 to 9.95 m . Based on the correlation of lateral and vertical variation, the stratigraphic succession can be grouped into two depositional interval i.e. depositional interval I & II. (IP.I & IP II). Vertical changes on the lithologic composition can be related to changes on humidity conditions. It is shown from the changes in the character of the facies between lower and upper lacustrine. Changes in basin centre between lower and upper lacustrine environment, as the result of basement movement caused by tectonic activity, impected to up and down movement of the basin floor. Keywords : Quaternary sediments, lacustrine, climate, tectonic
INTERAKSI FAKTOR KENDALI TEKTONIK, PERMUKAAN LAUT DAN PERUBAHAN KLIM DI DAERAH TELUK KLABAT, KABUPATEN BANGKA INDUK, BANGKA Hidayat, S.; Moechtar, Herman
Jurnal Geologi dan Sumberdaya Mineral Vol 19, No 1 (2009): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (614.07 KB)

Abstract

The study of the Quarternary deposits in Klabat gulf areas was based on the analyses of the sedimentology and stratigraphy of fifteen borehole information obtained along west to east. The penetration of the bore head varied from 3.50 to 16.80 m from + 21 m to - 4 m of sea-level. Whereas, the Quarternary sediments in the studied area can be divided into seven sedimentary environments, consisting of alluvial fan (FKa), swamp (FRw), floodbasin (FCb), deltaic (FDt), sand beach (FPp), nearshore (FLdp), and nearshore to offshore (FLdp to FLlp) deposits. Based on the lateral and vertical sedimentary environment correlations, the Quaternary stratigraphic succession can be divided into four sedimentary intervals (IP I to IV). Each interval is typically for topography and elevation changes which is controlled by changes of the sedimentary environment systems. The controlling main factor of the sedimentary environment system changes was regional and local tectonics. Changes in tectonic regime are important upon a tidal flat sedimentation. Keywords: facies, paleoenvironment, tectonic
Karakteristik Endapan Kuarter di Dataran Aluvial Rawa Utara Pangkalan Balai, Kabupaten Banyuasin (Sumsel) ( Suatu Studi Awal dari Efek Perubahan Iklim dalam Proses Sedimentasi) Moechtar, Herman
Jurnal Geologi dan Sumberdaya Mineral Vol 16, No 1 (2006): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (241.553 KB)

Abstract

The sediments in this area are of fluvial and swarnp systems, The fluvial deposits include channel sand, and fine grained cIay of floodplain deposits. The swarnp deposits of Iine-grained include humic clay and peaty clay, the basement of this Quaternary deposits is tufaceous clay of pyroclastic.The character of Quaternary depositional style at the PangkaIan Balai and surrounding is dominantly influenced by autogenic mechanisms (internal processes), such as river channel systems and sediment supply from the    surrounding hills.  The cIimate factor of allogenic rnechanisms (externaI processes) is specific to related humidity as chemicaI, physics, or biology aspects in time.Keywords: Fasies, fluvial and swamp, internal and external process.