INDONESIAN JOURNAL ON GEOSCIENCE

  

Indonesian Journal on Geoscience Vol. 1 No. 1 April 2014: 21-34

  INDONESIAN JOURNAL ON GEOSCIENCE Geological Agency Ministry of Energy and Mineral Resources Journal homepage: h�p://ijog.bgl.esdm.go.id

  ISSN 2355-9314 (Print), e-ISSN 2355-9306 (Online)

Limestone Microfacies of Baturaja Formation along

Air Rambangnia Traverse, South OKU, South Sumatra

  

Sigit Maryanto

Centre for Geological Survey, Geological Agency

Jln. Diponegoro No. 57 Bandung - 40122

  

Manuscript received: February 14, 2012, revised: March 18, 2013, approved: April 1, 2014

Corresponding Author: sigitmaryanto@ymail.com

Abstract

• Limestones of the Baturaja Formation occur at Air Rambangnia traverse, South Ogan Komering Ulu, South

  Sumatra, and they are used as objects for microfacies studies. The microfacies studies are based on a detailed petro-

  graphic analysis of thirty four limestone samples, taken from the traverse. Four types of the limestones are identified

  such as wackestone, packstone, grainstone, and floatstone. At least five microfacies form the limestone succesion of

  the Baturaja Formation. They are interpreted as sedimentary facies of very restricted bay and pond, back reef local

  slope, slope and shelf edge, winnowed platform edge sand, and reef flank facies.

  Keywords: Baturaja, limestone, petrography, microfacies, sedimentary facies

  Introduction The researched location was along Air Ram- bangnia River, in between Baturaja and Muaradua

  The term microfacies was first put forward by towns, administratively belonging to the area

Brown (1943; in Flugel, 1982). It is defined as of South Ogan Komering Ulu (OKU) Regency,

extensively discrete paleontology and sedimen- South Sumatra Province (Figure 1). The carbon- tology aspects, that can be grouped based on the ate rocks from Baturaja Formation are well found

type and number of components in petrographic along the Air Rambangnia traverse. This article

thin section and polished sample examination. was written with the aim to study the environment

Thereby, microfacies identifies environment of and deposition mechanism of those limestones

deposition based on petrography data (Maryanto, based on petrography data in relation to the divi-

2005 and 2008). Based on the type and number of sion of limestone microfacies. components, Flugel (1982) divides microfacies of limestone into twenty-four types according to the former division of facies zone by Wilson (1975). Methodology Wilson and Rosen (1998) stated that carbonate platform in the western part of Indonesia has ap- In order to achieve the study purpose, the

peared since the Late Oligocene. Bishop (2000a) research method includes field data collection

  IJOG

concluded that the Early Miocene of Baturaja and laboratory analysis. Field data collection is

Formation consists of carbonate platform sedi- a systematical rock sampling, which is based on

ments having totally thickness of 60 - 120 m. the results obtained by making detailed strati-

Bishop (2000b) divided Baturaja Formation into graphic column along Air Rambangnia traverse.

two lithostratigraphic units based on deposition, Laboratory work was done by quantitatively

i.e

  

. clastic sedimentary facies and limestone or petrographic analysis with point-counter for as

carbonate rock facies. many as 300 counts (Maryanto, 2007a). Important

  IJOG/JGI (Jurnal Geologi Indonesia) - Acredited by LIPI No. 547/AU2/P2MI-LIPI/06/2013, valid 21 June 2013 - 21 June 2016

  

Indonesian Journal on Geoscience, Vol. 1 No. 1 April 2014: 21-34

o o o o o 103 104 105 102 E

  106 E Muarabulan o o

  02 S

02 S

  Sungailiat JAMBI BANGKA BELITUNG

SOUTH SUMATRA

  Bangko Pangkalpinang

  

PROVINCE

Sarolangun o o

  03

  03 bangka Strait

  Sekayu PALEMBANG Lubuklinggau Argamakmur Kayuagung Prabumulih Curup Muaraenim Bengkulu o o Lahat

04 S

  04 S Pagaralam BENGKULU HINDIA

  

Baturaja

OCEAN

  Menggala Martapura Manna N LAMPUNG

Muaradua

_{0 100 Km} Kotabumi

  Investigated Traverse o o o o 103 104 102 E

  105 E Figure 1. Location map of South Sumatra Province and the investigated traverse at Air Rambangnia River. aspects of petrography to be identified include: consisting of granite, andesite-basalt, metasedi-

  1. the proportion of major components, such as ment, mélange, and metamorphic rocks. Uncon- carbonate grains, terrigenous grains, matrix, formable overlying the basement rocks there are neomorphism materials, cement, and rock several Tertiary Formations of Kikim, Talangakar, porosities

  Baturaja, Gumai, Airbenakat, Muaraenim, Ranau, 2. identification of the characters of each com- Kasai, and Alluvium (Gafoer et al., 1986, 1993; ponents,

  Figure 2). Limestone of the Baturaja Formation 3. texture of rocks that include fabric, sorting, in general was deposited in the back-reef environ- grain size, and shapes. The classification is ment behind the edge of the basin during the Early determined according to Dunham (1962) de- Miocene (Maryanto, 2007b). Layered limestone veloped by Embry and Klovan (1971). can be observed directly along the Air Rambangnia Microfacies interpretation of the limestones traverse. The rocks are generally sloping ramps to

from the Baturaja Formation along Air Rambang- the east (Figure 3), with the total thickness of about

nia traverse is divided according to the standard 220 m, measurable reach including carbonate rocks

classification of microfacies from Flugel (1982) from the Baturaja Formation of 196 m thick.

and facies zone from Wilson (1975). As a compari- Volcanic rocks of the Kikim Formation are

son, there are also references from many authors presented as a basement. It consists of volcanic

that discuss microfacies and limestone depositional breccias, volcanic sandstone, mudstone, and

environment, such as Andreeva (2008), Jones and conglomeratic sandstone, with andesite lava inser-

Desrochers (1992), Kindler and Hearty (1996), tions. The Baturaja Formation limestone uncon-

  IJOG

Read (1985), and Tucker and Wright (1990). formably overlies the Kikim Formation (Figure 4).

  The lower part of Baturaja Formation was initiated by the presence of grainstone containing Geological Review some pore-dissolving porosities. Furthermore, the rocks become developed onto layered wackestone- Regional geology in-between Baturaja and packstone that partially argillaceous with oriented

  

Muaradua area is preceded by Pre-Tertiary rocks fossils of mollusks (Figure 5) and algae. Several

  

Limestone Microfacies of Baturaja Formation along Air Rambangnia Traverse, South OKU, South Sumatra (S. Maryanto)

103 54’ E

  104 15’ E Qa Tma

  06’S Qtk Qhv N

  06’S

04 BATURAJA

  04 aka

  Tmpm Air S

  0 10 Km Air Suban Besar

  Qtk SUMATERA

  Tpok Tma Batuiputih Tomt

  Tmb EXPLANATION:

  15 Tmg

  15 Tmb Qa Tmg Alluvium tu

• -ba

  Y

  15 atu

  INDEX MAP Qv Tuff Volcanic Unit Negerisindang

  Air B Tmb Air Laja a amb

  12 Qhv Volcanic Unit

  15 TERNAR Air T Qtk

  QTk Kasai Formation Penyandingan

  QUAR

  10 QTr Ranau Formation

  24 Tomt Tma Tma

  Tmpm Muaraenim Formation

  17 Tpok

  15 Tmg Tma

  13 Airbenakat Formation ebangka Qhv Air T Tmg Gumai Formation

  Qhv MIOCENE

  Kungkilan Tmb Baturaja Formation

  Air Lahat

  15 Tmpm Tomt Talangakar Formation

  Tma Tpok Kikim Formation

  Tpok Tpokc PALEOGENE Cawang Mem. Kikim Fm.

  Pct

Tomt

Km Melange Complex

  Air L Tmg

  Kjg Garba Formation eng

  Y Air Buluh

  Sundan Sagarakembang kaja p

  KJgv Insu Mem. Garba Fm. TIAR Tmb Sukoraja Air Kura-kura

  Kjgs KJgs Situlanglang Mem. Garba Fm.

  Qtk PRE-TER Garba Granite Kgr

  

Negeriratu

Pct Tarap Formation Pct

  Tpok Qtk

  Air Rambangnia Traverse Kjgv Kjgv

  Tpok Air Kiti

  Tmpm Tma Tmg Tmb

  Air Napalan Sabahlioh Qa

  KJgs Tpok Air Saman

  Air Gilas Qtk Kjg

  .

  Tmpm Kgr Airbungin Tmb Baturaja

  Air Rambangnia Qtk Pct Simpang

  Tanjungkurung Kgr Qtr

  Kgr Karangagung Kjgv Pct

  Km Qtr Tpokc Umbulanmeliku

  15 KJg Tpokc Saungnaga

  Kgr Air M Mehanggin

  Tmb alau Tomt Qv Kotakarang

  Kjgv

  10 Qtr Kgr

  10 Tmb Tmb Tanjungbringin

  Air Saka

  25 Tpokc Qa PCt Negeriagung

  15 Tmg Qv Tma Qa

  Tomt Air Komering

  Air Kemu Qtr

  

MUARADUA

Qa Tmpm Qtr Qa Tmb

  17 Kotamarga Qa Air Selabung

  Tmpm Qtr Qa Gedong

  35’S Tmg 35’S Tma

  Umbulantelok Qtr Tmpm Qtr Sukaraja

  19

  04

  04 103 54’E

  104 15’E

  IJOG

Figure 2. Geological map of Muaradua area, South Sumatra (Gafoer et al., 1993) and locations of Air Rambangnia traverse

(Maryanto, 2007a and 2008).

floatstone intercalations are found containing some The middle part of Baturaja Formation is

coral skeletons. Stylobed is interlayering between composed of floatstone (Figure 6), of which later

wackestone-packstone with marl ended the deposi- evolved into argillaceous wackestone. Interlayers

tion of the lower part of Baturaja Formation. between floatstone with wackestone-packstone

  IJOG

Indonesian Journal on Geoscience, Vol. 1 No. 1 April 2014: 21-34

dominated the sequence, which are later fining upward onto sometimes argillaceous wacke- stone-mudstone. The next lithology is found as floatstone.

  

10

  10

  8

  7

  15

  12

  8

  8

  324 325 326 327

  10

  12

  10 SM301A SM302A SM302B SM303A SM303B SM304A SM304B SM304C SM304D SM305A SM305B SM305C SM309 SM310 SM314A SM314B SM315A SM315B SM316A SM316B SM317A SM317B SM318A SM318B SM320A SM320B SM321A SM321B SM323A SM323B SM323C SM323D SM323E SM324A SM324B SM324C SM325A SM325B

  Volcanic breccia and sandstone with mudstone and lava intercalations Conglomeratic sandstone overlain by packstone Argillaceous wackestone with floatstone intercalations Bedded wackestone sometimes argillaceous Clayey sandstone Argillaceous wackestone Carbonaceous mudstone and sandstone Floatstone and wackestone sometimes argillaceous Bedded floatstone with argillaceous packstone-wackestone Bedded floatstone with argillaceous packstone-wackestone Argillaceous wackestone-mudstone Thick bedded floatstone Argillaceous wackestone-mudstone

Argillaceous wackestone-mudstone

Argillaceous wackestone-mudstone with lot of concretions Argillaceous wackestone-mudstone with concretion bedding Argillaceous wackestone-mudstone overlied by grainstone Grainstone, wackestone and packstone Bedded wackestone-packstone A

  B Section A - B Alluvium Kikim Formation Baturaja Formation

  B A To Muaradua To Baturaja S 04 25’ 11,3” E 104 08’ 40,0” S 04 25’ 08,5” E 104 09’ 30,5” S 04 25’ 10,0”, E 104 09’ 02,6”

  24

  320 321 322 323

  The upper part of Baturaja Formation begins with the presence of wackestone-mudstone lay- ers. Stylobedded and or siliceous concretional bedding reaches 80 cm in size are often found in these layers (Figure 7). The concretional bedding sometimes has a parallel direction to the bedding (forming lens) and it shrinks to the upper part. The above concretional beddings are overlain by gradational and planar cross-bedding grain- stones (Figure 8). Carbonate rock sequences in this traverse is ended by wackestone-packstone sometimes with dissolving porosities.

  0 400 m N

  The carbonate rocks of Baturaja Formation partially do not crop out along Air Rambang- nia traverse, especially between sites 306-213. Among that locations, the clastic sedimentary rocks from Muaraenim Formation are exposed in the form of claystone containing limestone boul- ders. The sedimentary rocks are preserved due to a tectonic strike-slip fault in N33 o E direction.

  Petrography Based on a detailed petrography analysis, the limestone types recognized are wackestone, packstone, sandy packstone, grainstone, and float- stone. Each of these rocks, including the number and type of the rock components would later be used as the basis for microfacies determination (Table 1).

  Wackestone Wackestone group also includes sandy mudstone-wackestone, which is present as an intercalation. The rocks are generally massive with fine-grained fragmental bioclastic texture.

  Bioclast always occur and comprises diverse type, size, and amount of fossil. Nevertheless, fossil types composing the rock can be identified, such as red algae, mollusks, and foraminifera. Rarely intraclast or extraclast are preserved in the rocks, the same as the presence of pellets. Terrigenous materials are still observed in some rock samples with limited amounts, scatteredly, and uneven. They are composed of quartz, feldspar, volcanic

  

Figure 3. Detailed stratigraphic measured map along Air Rambangnia traverse (Maryanto, 2007a and 2008) and sample

locations.

  Figure 3. Detailed stratigraphy measure map along Air Rambangnia traverse (Maryanto, 2007a & 2008) and sample locations.

  305

  316 317 318 319

  05SM305 EXPLANATION: Outcrop location

  Strike and dip Fault (predicted) Number of site Sample location River flow direction

  10 301 302

  303 304 305 306 307

  308 309 310 311

  312 313 314 315

  SM326 196 m

  

Limestone Microfacies of Baturaja Formation along Air Rambangnia Traverse, South OKU, South Sumatra (S. Maryanto)

Y AND AR SYMBOL T S

  ACIES LITHOLOGY DESCRIPTION A G E U N I SAMPLE CODE GRAIN SIZE STRUCTURE MICROF THICKNESS (meter) LITHOLOGY AND SEDIMENT

  CL FS CS PB BO MS ST GR CO 220

  SM326 SMF10-FZ7

  SM325B SMF10-FZ7

  Bedded packstone-wackestone with various fossils SM325A

  SMF10-FZ7 SMF12-FZ6 SM324C

  SMF12-FZ6 SM324B

  Grainstone sometimes with cross-bedded structure SMF12-FZ6

  SM324A SMF12-FZ6 SMF19-FZ8 SMF10-FZ7

  SM323B Wackestone-mudstone partially chalky and recrystallized with

  SM323E SMF10-FZ7

  SM323D

lot of concretion fining upward

  SM323C SMF3-FZ3

  Upper part SM323A

  Stylobedded wackestone-mudstone SM321B

  SMF19-FZ8 SM321A

  Wackestone-mudstone partially with quartzitic concretion SMF10-FZ7

  SM320B SM320A Thick bedded floatstone partially develop to rudstone

  SMF5-FZ4 165

with wackestone intercalations

  SMF5-FZ4 SM318B

  Wackestone-mudstone partially argillaceous SMF10-FZ7

  SM318A SMF5-FZ4

  SM317B SM317A SMF10-FZ7

  SM316B SM316A Floatstone interlayering with packstone-wackestone SMF5-FZ4 A

  SM315B A J Floatstone thick bedded and poorly sorted SMF5-FZ4

  Middle Part SM315A M I O C E N E

  SMF10-FZ7 T U R SM314B Wackestone generally argillaceous with molluscs orientation

   Y SM314A A Floatstone coral and lithoclast with molluscs-rich matrix SMF5-FZ4

  B A R L E 110

  Fault Zone SM305C SM305B

  SMF19-FZ8 SM305A

  Wackestone bedded, sometimes argillaceous with floatstone SM304D SM304C rudstone intercalations

  SM304B SMF10-FZ7

  55 SM304A Wackestone-packstone generally argillaceous with fossils

  SMF12-FZ6 SM303B dominated by molluscs and algae

  SM303A Lower Part

  SM302B Stylobedded grainstone with several dissolution pores SMF11-FZ6

  SM302A Volcanic breccia and sandstone cruedly bedded with

  IJOG intercalations of mudstone, conglomeratic sandstone, and andesite lava

  KIKIM SM301A

  EOCENE-OLIGOCENE CL FS CS PB BO ST MS GR CO

  

Figure 4. Detailed lithostratigraphy column along Air Rambangnia traverse, OKU Selatan, South Sumatra (Maryanto, 2007a

& 2008, with modifications).

  

Indonesian Journal on Geoscience, Vol. 1 No. 1 April 2014: 21-34

Figure 5. Massive marl contains a lot of mollusk mouldics, this point is as the lower part of the Baturaja Formation.

  Figure 8. Grainstone overlying mudstone-wackestone, pres- Photographed in the 303 site of the Air Rambangnia traverse. ents as a constituent of the upper part of Baturaja Formation. Photographed in the 324 site of Air Rambangnia traverse.

  Clay mineral matrix in general is inseparable with carbonate mud matrix. The cement material is always present with very limited quantities, par- ticularly as orthosparite, iron oxides, authigenic clay minerals, and silica.

  Packstone Packstone is generally massive with fine- to medium - grained fragmental bioclastic texture.

  Bioclast is composed of diverse type, size, and Figure 6. Very poorly sorted floatstone composing of the amount of fossil, however, it is predominated middle part of Baturaja Formation. Photographed in the 314 site of the Air Rambangnia traverse. by red algae, mollusks, and foraminifera. Intra- clast or exstraclast is present on the coarser size of limestone fragments, spread unevenly, and consists of coralline, bioclastic, and argillaceous limestones. Less amount of very fine pellet some- times changes into microsparite. Sparsely, terrrig- enous materials are still present sporadically dis- tributed, or sometimes excessively influence the rock name to become sandy. The rock matrix is mainly preserved as carbonate mud, which often changes onto microsparite and/or is recrystallized to form pseudosparite together with carbonate grains. Cement materials are always present in the

  Figure 7. Outcrop of wackestone-mudstone containing rocks as various amount of orthosparite calcite, siliceous concretions, is a constituent of the upper part of and rarely of iron oxides.

  Baturaja Formation. Photographed in the 322 site of Air

  IJOG Rambangnia traverse. Grainstone

and sedimentary rock fragments, unidentified Grainstone is generally massive with medium-

rock fragments, phosphate, and glauconite. Car- to coarse - grained fragmental bioclastic texture.

bonate mud matrix often have changed into mi- Bioclast is quite dominant consisting of various

kind, size, and amount of fossil. Intraclast or crosparite, some even have recrystallized to form

pseudosparite together with carbonate grains. extraclast is observed unevenly in some coarse-

SAMPLE CODE DESCRIPTION SM 302B SM 303A SM 303B SM 304A

  Percentages Carbonate Grains

  Green algae Bryozoans Echinoderms Coral Benthic foraminifera Planktonic foraminifera Brachiopods Moluscs Ostracods Sponge-spicules Bioturbation Unidentified fossils Intraclasts / extraclasts Pellet / peloids Oolite / oncolite

  Sumatra (Maryanto, 2007a)

  

SM

304C

SM 304D SM 305A SM 305B SM 305C SM 314A SM 314B SM 315A SM 315B Structure m m o m m m m m f m o f m m m m o m Texture bf bf bf bf bfc bfc bf bf bf bf bf bf bf

  Sorting

  m p p p p p p p p vp p vp vp

  Fabric c c c o o o o o o o o o o

Av. grain size (mm) 1.80 0.70 1.40 0.30 0.20 0.20 0.20 0.80 0.20 0.80 0.80 1.20 1.80

Grain shape sr sr sr sr sr sr sr sr sr sr sr sr sa Grain contacts p l c p l c p l c f f f f p f f f p f f p f p l

• 4.33
• 1.00
• 1.33
• 4.00
• 1.33
• 3.00
• 8.00
• 0.67
• 5.67
• 1.67
• 1.67
• 1.33
• 1.33
• 1.33
• 0.67
• 0.67
• 1.00
• 2.00
• 5.00
• 5.33
• 8.33
• 6.33
• 24.67
• 9.67
• 9.67
• 6.00
• Terrigenous Grains
• 1.33
• 1.33
• 3.00
• 1.00
• 0.67
• 1.33
• 0.67
• 3.33
• 1.00
• 0.33
• 4.67
• 2.67
• 0.67
• 0.67
• 4.67
• 50.33
• 15.00
• 34.00
• Cementing Materials
• 6.00
• 26.67
• 3.00
• 1.00
• 1.67
• 1.33
• 0.33
• 1.00
• 3.00
• 0.67
• 24.00
• 21.67
• 1.33
• 0.67
• 0.67
• 52.33
• 20.33
• 17.00
• 7.33
• 8.00

  IJOG

Limestone Microfacies of Baturaja Formation along Air Rambangnia Traverse, South OKU, South Sumatra (S. Maryanto)

Table 1. Petrography Analysis Summary of the Limestones from Baturaja Formation along Air Rambangnia Traverse, South

  0.67

  2.00

  0.67

  2.33

  2.67

  1.67

  3.33

  4.00

  2.33

  1.67

  2.00

  4.00

  1.33

  1.67

  2.67

  3.33

  3.67

  8.00

  1.67

  0.67

  2.67

  1.67

  Matrix

  2.00

  0.67

  0.67

  1.00

  0.33

  1.33

  1.67

  0.33

  Carbonate mud Clay minerals

  9.67

  3.33

  32.33

  22.00

  3.00

  10.33

  6.00

  39.33

  Orthosparite Iron oxides Authigenic clays Silica

  6.33

  Neomorphisms

  3.67

  1.00

  16.00

  1.00

  3.00

  2.67

  5.67

  4.00

  0.67 Porosities Intraparticle Mouldic Vuggy Intercrystal S helter dan fenestrae Fracture

  1.33

  1.67

  2.33

  1.33

  1.00

  1.00

  4.33

  0.67

  1.67

  0.67

  2.00

  3.33

  28.33

  Microsparite Pseudosparite Dolomite Micritized mud Pyrite

  59.33

  16.33

  6.33

  7.00

  1.33

  0.67

  26.00

  6.00

  1.00

  51.67

  8.33

  5.67

  2.00

  5.00

  28.00

  9.00

  1.00

  51.33

  0.67

  2.33

  1.33

  2.67

  0.67

  4.33

  2.67

  5.00

  1.33

  1.33

  0.67

  7.33

  5.67

  3.67

  1.00

  1.67

  0.67

  5.00

  0.33

  3.33

  0.67

  1.00

  6.00

  1.00

  4.67

  1.33

  0.67

  4.67

  6.00

  1.33

  2.00

  15.00

  5.33

  10.67

  16.33

  4.00

  0.67

  7.33

  2.67

  0.67

  5.33

  0.33

  0.67

  4.00

  1.67

  2.33

  1.33

  0.33

  0.67

  3.00

  4.33

  1.00

  Quartz Feldspar Rock fragments Glauconite Phosphate Opaque minerals Carbon

  1.33

  0.67

  0.33

  6.33

  1.33

  0.67

  10.33

  1.33

  0.67

  2.00

  1.00

  0.67

  1.67

  0.67

  2.33

  4.67

  2.00

  0.67

  13.00

  1.67

  0.67

  5.67

  1.33

  3.33

  6.33

  0.67

  1.33

  4.00

  1.67

  0.67

  3.33

  1.33

  1.67

  1.33

  8.33

  5.00

  0.67

• 0.67
• 1.00
• 1.00
• 1.33
• 0.67
• 1.67
• 0.67
• 2.33
• 1.67
• Rock Name G SP SP W W W W W W W W W W/F SMF / FZ 11/6 12/6 12/6 10/7 19/8 19/8 10/7 10/7 19/8 10/7 10/7 10/7 5/4

SAMPLE CODE DESCRIPTION SM 316A SM 316B SM 317A SM 317B

  1.45

  Green algae Red algae Echinoderms Coral Benthic foraminifera Planktonic foraminifera Brachiopods Moluscs Ostracods Sponge-spicules Bioturbation Unidentified fossils Intraclasts / extraclasts Pellet / peloids Oolite / oncolite

  Grain shape sr sr sr sr sr r sr sr r sr r r r Grain contacts p l c p l c p l c f p l c f p l c p l c f f f p l p l c f p l Percentages Carbonate Grains

  0.70 1.60 0.70 1.40 0.40 0.20 0.15 0.15 0.35 0.15

  1.40

  

SM

318A

SM 318B SM 320A SM 320B SM 321A SM 321B SM 323A SM 323B SM 323C Structure

  m m o m m m m m f m m f m o m o m p m

  Texture bf bf bf bf bf bf bf bf bf bf bf bf bf Sorting vp p p p p p p p p p p p p Fabric c c c o c o c c o o o c o Av. grain size (mm)

  1.40

• 2.33
• 0.67
• 4.00
• 1.33
• 2.33

• 4.67

• 0.67
• 2.33
• 7.33
• 4.67
• 0.33
• 1.33
• 1.00
• 0.67
• 3.00
• 6.00
• 6.33
• 6.00
• 1.33
• 5.00

• 4.00
• Terrigenous Grains
• 2.67
• 0.67
• 1.33
• 0.67
• 0.67
• 3.00
• 0.67
• 0.67
• 0.33
• Matrix
• 1.67
• 0.67
• 0.67
• 10.00
• 10.00
• 13.33
• 13.67
• 10.67
• 9.33
• 28.33
• 0.67
• 4.00
• 4.67
• 1.33
• 1.00
• 0.67
• 0.67
• 0.67
• 0.67
• 0.67
• 7.00
• 7.00
• 11.33
• 60.33
• 8.00
• 56.33
• 10.67
• 20.67
• 27.67

  IJOG

Indonesian Journal on Geoscience, Vol. 1 No. 1 April 2014: 21-34

Table 1. .............continued (Maryanto, 2007a)

  2.67

  4.00

  10.67

  7.00

  5.00

  8.00

  22.33

  8.00 Cementing Materials Orthosparite Iron oxides Authigenic clays Silica

  8.00

  1.67

  0.67

  1.67

  5.67

  1.67

  6.00

  0.67

  11.00

  1.67

  3.00

  1.33

  0.67

  0.67

  4.33

  1.33

  9.33

  6.00

  9.33

  1.67

  0.67

  1.00

  0.67

  1.67

  0.33

  2.00

  0.67

  1.33

  0.67

  0.67

  0.67

  0.67

  4.67

  0.67

  0.33

  1.00

  0.67

  1.00

  1.33

  0.67

  0.67

  Carbonate mud Clay minerals

  23.33

  1.00

  3.33

  5.67

  Porosities

  10.67

  30.67

  3.00

  21.67

  0.67

  5.00

  5.00

  5.67

  2.00

  2.00

  9.67

  Intraparticle Mouldic Vuggy Intercrystal S helter dan fenestrae Fracture

  1.67

  1.33

  1.33

  3.67

  0.67

  2.33

  1.33

  4.33

  0.67

  0.67

  0.67

  1.67

  20.67

  6.00

  1.33

  Microsparite Pseudosparite Dolomite Micritized mud Pyrite

  1.33

  1.67

  0.67

  1.33

  5.33

  1.33

  4.33

  3.00

  3.00

  1.00

  Neomorphisms

  7.33

  5.00

  6.00

  4.00

  17.00

  4.67

  3.00

  4.00

  2.67

  6.67

  4.00

  1.00

  3.00

  0.67

  2.33

  0.67

  1.00

  0.33

  5.00

  4.00

  1.33

  1.33

  1.00

  4.00

  3.33

  0.67

  3.67

  4.00

  1.00

  9.67

  0.67

  2.33

  19.33

  0.67

  3.00

  3.00

  2.67

  1.00

  1.33

  2.67

  21.67

  0.67

  7.67

  1.33

  1.33

  4.67

  16.33

  0.33

  0.67

  5.67

  0.67

  4.67

  9.33

  0.67

  2.33

  2.67

  7.00

  17.00

  2.33

  1.33

  13.67

  1.67

  2.00

  1.33

  0.67

  4.33

  1.33

  5.33

  1.67

  0.33

  0.67

  4.00

  1.33

  2.67

  0.67

  5.33

  16.33

  0.67

  2.33

  0.67

  1.33

  19.67

  10.33

  8.00

  3.00

  6.00

  2.67

  4.67

  8.33

  1.67

  7.33

  6.00

  Quartz Feldspar Rock fragments Glauconite Phosphate Opaque minerals Carbon

  1.33

  0.67

  1.67

  1.67

  6.00

  1.00

  5.33

  1.33

  2.67

  7.67

  0.67

  1.00

  12.33

  1.33

  6.33

  7.33

  0.67

  1.67

  1.67

  1.67

  4.33

  2.67

  2.33

  9.67

  1.00

  5.00

  4.00

  1.67

  1.67

  1.33

  2.33

• 0.67
• 3.33
• 1.00
• 2.67
• 1.67
• 0.67
• 8.67
• 0.67
• 0.67
• Rock Name P/F P P W P W P P W W W P W SMF / FZ 5/4 10/7 5/4 10/7 5/4 10/7 5/4 10/7 10/7 19/8 3/3 10/7 10/7
• 0.67
• 0.67
• 0.67

SAMPLE CODE DESCRIPTION SM 323D SM 323E SM 324A SM 324B SM 324C SM 325A SM 325B SM 326 EXPLANATION

  Texture bf bf bf bf bf bf bf bf Sorting p p m m p p p p Fabric c o c c c c c c Av. grain size (mm)

  Green algae Red algae Bryozoans Echinoderms Coral Benthic foraminifera Planktonic foraminifera Brachiopods Moluscs Ostracods Sponge-spicules Bioturbation Unidentified fossils Intraclasts / extraclasts Pellet / peloids Oolite / oncolite

  Grain contacts p l f p p l c p l c p l c p l c p l c p l c Percentages Carbonate Grains

  0.35 Grain shape sr sr sr sr sr sr sr sr

  0.15 1.20 1.60 1.10 0.80 0.30

  0.30

  Structure m m o m p m m m m p m Structure:

  m = massive o = with grain orientation p = with several pores f = with joints and fractures

• 5.67

  bf = bioclastic fragmenter cf = clastic fragmenter nc = non-clactic c = crystalline

• 5.00

• 2.67
• 0.67

  Carbonate mud Clay minerals

  0.67

  0.67

  1.00

  1.00

  0.33

  1.33

  5.00

  9.33

  0.33

  17.33

  4.00

  6.00

  5.00

  12.67

  5.67 Cementing Materials Orthosparite Iron oxides Authigenic clays Silica

  2.67

  1.00

  0.67

  1.00

  2.00

  0.67

  2.67

  3.33

  4.67

  3.33

  29.00

  0.67

  11.33

  1.00

  0.67

  2.67

  3.33

  1.00

  Quartz Feldspar Rock fragments Glauconite Phosphate Opaque minerals Carbon

  0.67

  1.00

  0.67

  1.33

  1.67

  6.33

  2.67

  6.67

  3.00

  6.00

  2.00

  4.00

  8.00

  0.67

  3.00

  3.33

  4.00

  2.67

  0.67 Porosities Intraparticle Mouldic Vuggy Intercrystal S helter dan fenestrae Fracture

  1.33

  1.67

  3.33

  0.67

  2.33

  14.00

  5.67

  14.00

  1.00

  1.67

  1.33

  1.33

  1.00

  1.33

  0.67

  1.33

  0.67

  7.33

  4.67

  6.00

  3.33

  2.67

  Neomorphisms

  Microsparite Pseudosparite Dolomite Micritized mud Pyrite

  6.00

  3.00

  1.33

  5.67

  2.67

  2.67

  6.33

  4.00

  3.33

  4.67

  4.00

  2.67

  6.33

  4.67

  9.33

  5.33

  3.33

  10.33

  2.67

  22.00

  0.67

  2.00

  2.67

  2.67

  Sorting:

  Rock name:

  vw = very well sorted w = well sorted m = moderately sorted p = poorly sorted vp = very poorly sorted

• 6.00

  Fabric:

  c = closed o = opened

  Grain shape:

  va = very angular a = angular sa = sub-angular sr = sub-rounded r = rounded wr = well rounded

  Grain contact:

  f = floating p = point l = long c = concave-convex s = sutured

  BW = Wackestone BW/F = Wackestone/floatstone BP = Packstone BP/F = Packstone/floatstone BG = Grainstone SBP = Sandy packstone

  7.67

  Microfacies:

  SMF = Standard microfacies (Flugel, 1982) FZ = Facies zone

  (Wilson,1975)

  Texture:

  IJOG

Limestone Microfacies of Baturaja Formation along Air Rambangnia Traverse, South OKU, South Sumatra (S. Maryanto)

Table 1.............continued (Maryanto, 2007a)

  0.67

  4.67

  17.00

  3.67

  0.67

  14.00

  4.67

  2.00

  3.33

  4.00

  11.33

  2.67

  2.67

  1.33

  3.33

  4.00

  2.33

  0.67

  1.67

  2.00

  3.00

  10.33

  0.67

  5.33

  4.33

  0.67

  2.33

  9.33

  1.33

  19.67

  1.33

  1.67

  30.33

  6.00

  4.67

  0.67

  1.67

  6.67

  3.33

  14.00

  4.67

  4.00

  23.00

  4.33

• 6.00

• Terrigenous Grains
• 1.33
• 0.67
• 0.67
• 0.33
• 0.67
• 0.67
• 1.33
• Matrix
• 0.67
• 12.33
• 13.00
• 6.67
• 4.33
• 7.67
• 9.00
• 6.00
• 7.67
• 3.00
• 1.00
• 15.00
• 5.33
• 6.33
• 2.33
• 10.33
• 1.00
• 5.67
• 1.67
• 2.67
• 0.33
• Rock Name P W G G G P P P SMF / FZ 10/7 19/8 12/6 12/6 12/6 10/7 10/7 10/7
• 0.67
• 0.67
• 0.67
• 0.67

  IJOG

Indonesian Journal on Geoscience, Vol. 1 No. 1 April 2014: 21-34