Definitions of Pre-Pleistocene formation names in Java

Pleistocene formations are in a separate file

INDEX

Lawak Beds, Ledok Fm., Lengkong Beds, Lidah Fm., Ligung Series, Lutut Beds, Madura Fm., Malo limestone Mbr., Marl-tuff horizons, Masigit limestone, Menengteng-canyon Layers, Menuran Layers, Merawu Beds, Mundu Fm., Nanggulan Beds, Ngembak Layers, Ngimbang Fm., Nglarangan Layers, Ngrayong Fm., Njalindung Beds

 LAWAK BEDS (Formation) (Lawak Serle) Miocene

Haar (C. ter) (1934). Toelichting bij Blad 58 (Boemiajoe). Geol. kaart van Java, 1 / 100,000, pp. 15-16.

Greenish marls with about 4 intercalations of thin foraminiferal limestone beds and calcareous sandstone, with a mean thickness of 0.5 m each. The foraminiferal limestone are characteristically entirely made up of forams, mainly Lepidocyclina and Cycloclypeus. The thickness of this part is about 150 m. On top are indistinctly bedded Globigerina marls, with thin sandstone beds intercalated.

The Lawak Beds are overlying the Rambatan Beds (Formation) in some places, but seem generally to pass laterally into the latter, or into the upper part of the Pemali Beds (Formation), as the Halang Beds (Formation) are overlying all three stages perfectly conformably in different places. Quick changes of facies are anyway to be expected in the shelf deposits which they all represent. The content of foraminifera is moreover quite similar in all beds underlying the Halang Beds, indicating a Tf3-4 age*. The Halang Beds themselves are everywhere distinguished by a revived volcanism, and therefore are more reliable as a stratigraphic unit.

Type locality: Kali Lawak (Lawak River), long. 108° 57' E, lat. 7° 5' 30" S near Bumiayu, SW of Ceribon, C. Java.

Geograplical distribution: Only in a few small areas, the most important being an area of about 1 sq. km. at long. 108° 53' 30", lat. 7° 7' 30" S where a good section is disclosed in the Cirambatan; further on sheet 54 (l/100,000) of Java geol. surv.

Diagnostic fossils: Trybliolepidina rutteni van der Vlerk; T. martini Schlumberger, Cycloclypeus indopacificus var terhaari Tan, C. postindopacificus var. postterhaari Tan, C. inornatus var. inornata Tan, Radiocycloclypeus radiatus Tan, R. stellatus Tan.

References: Hetzel (W.H.) (1935), pp. 14-15; Bemmelen (R.W. van) (1949a), p. 605.

Bemmelen (R.W. van) (1949). The Geology of Indonesia, vol. la, pp. 586-587.

"Glauconite sandstones, alternating with platy limestones and softer sandstones, with small foraminifera, often cross bedding. Delta Formation. Thickness about 200 m", in the Cepu area, between 30-60 km S of Rembang. Near Rembang, more to the North, this formation is possibly represented by the so-called "Karren-limestone", a massive limestone typically weathering to a karren-surface where it is exposed.

The Ledok Formation (Karren Limestone Formation) overlies with a stratigraphic hiatus the Rembang Beds near Rembang, but covers conformably the Wonocolo Formation near Cepu. It is in turn overlain by the Mundu Formation. The correlation is uncertain. Possibly it may be correlated with the lower part of the Upper Kalibeng, or the upper part of the Lower Kalibeng Formation.

Type locality: quoted from B.P.M.

It may be safely assumed that the type-locality of this formation is to be found somewhere on the flanks of the Ledok anticline, about 8 km NNW of Cepu.

Furthermore, in view of the fact, that the correlation of the various formations and members of the Java stratigraphy is not very clear yet, it might, be better to omit the implication that the Ledok formation and the Karren Limestone formation are probably the same. It is on the other hand, probable that a part of the Karren-kalk formation has to be correlated time stratigraphically with the Ledok formation but certainly not the whole sequence.

Geograpical distribution: Rembang - Cepu Anticlinorium, between Demak, near Semarang, in the west, to Madura in the east, over a distance of 200 km. The N-S dimension of this area is about 60 km in its broadest parts between Rembang and Cepu, N. Java.

Diagnostic fossils: none mentioned.

See: Cimandiri Complex.

Bemmelen (R.W. van) (1938). De Ringgit-Beser. Nat. Tijdschr. van Ned. Indie, vol. XCVIII, pp. 171-194.

Marly tuff-sandstones and conglomerates, deposited in a marine environment. They are overlain by the Ringgit Series (Formation) and conformably overlie the marine sedimentary Menuran Layers.

Type locality: Leprak, 5 km East of G. Beser, 1 0 km N of Bondowoso, N part of East Java.

Geographical divtribution: a small area around type locality only.

Reference: Bemmelen (R.W. van) (1949), pp. 552-553.

Bemmelen (R.W. van) (1937). Toelichting bij blad 66 (Karangkobar). Geol. kaart van Java, 1 / 100,000 pp. 24-26.

Andesitic agglomerates overlying the Pliocene or Upper Miocene Bodas Series (Formation). On top of the agglomerates follow tuffaceous clays, breccias and thin conglomerates. Autochthonous plant- remains indicate nonmarine surroundings of deposition, while the low degree of carbonization indicates a young, possibly Upper Pliocene or even Pleistocene age.

The formation is overlain by young volcanics.

Type locality: Kali Ligung (River), near the S limit of sheet 66, long. 109° 36' 12" E. lat. 7° 19' 25," S.

Geographical distribution: a strip of 13 km length in EW direction, W of the type locality. The breadth of the strip varies between 1 and 3 km.

Reference: Bemmelen (R.W. van) (1949a), p. 606.

Locally developed Miocene conglomerates, forming the base of the Merawu Beds (Formation) .

See: South Serayu Miocene.

Obsolete term for fossiliferous beds exposed in the Ci Menenteng near Waled, Cirebon, W Central Java. Martin (Samml. d. geol. Reichsmus. Leiden, serie 1, Bd. VI, 1900), describes the molluscan fauna (54 % of recent species) and assumes a Pliocene age. (See also Samml. geol. Reichsmus. Leiden, Beil. Bd. 1919, pp. 29, 131, 132; and Cheribonian Stage, in Oostingh's Molluscan Stratigraphy, of the Neogene).

Reference: Zwierzycki (J.) (19 13), p. 113; Oostingh (C.H.) (1938), p. 5 14.

Bemmelen (R.W. van) (1938). De Ringgit-Beser, Nat. Tijdschr. van Ned. Indie, vol. XCVIII, pp. 171-194.

Globigerina-bearing tuff-marls and radiolaria-bearing clay-marls, possibly a facies of the Pacalan Limestone.

Type locality: Menuran, halfway between Bondowoso and Situbondo, N part of East Java.

Geographical distribution Area of about 10 square km around type locality only.

Reference: Bemmelen (R.W. van) (1949a), p. 552.

Bemmelen (R.W. van) (1937) Toelichting bij Blad 66 (Karangkobar), Geol. Kaart van Java, 1 / 100,000, pp. 11 - 13.

A flysch-like series of conglomerates, containing milky quartz and Lepidocyclina limestone, andesitic tuff and basalt, at the base, (only developed in sheet 73-74), followed by quartz-sandstones, claystones and Globigerina marls. The sandstones contain biotite, tourmaline, rutile, etc.; it is clear that the Merawu Beds overlie unconformably the metamorphic Pre-Tertiary from which these minerals must have been derived.

In the upper parts of the series the conglomerates disappear, and the beds are composed of thin-layered sandstones, calcareous sandstones, and marly claystones, with ripple-marks, worm-tracks and hexagonal shrinkage fissure patterns, indicating a "wadden" like surrounding of deposition, and much resembling the "Flysch" facies of the alpine region. It is a typical synorogenetic facies. Layers of dacitic and liparitic tuffs occur in many levels, while coarse andesite tuffs and lahar-breccias occur in the area SE of Kali Merawu. Basalts of Penyatan age were intruded as sills, dikes, necks and bosses in the Merawu beds. The basal beds of the Merawu Series are in some places developed in a calcareous-conglomeratic facies

1. The Sigugur Limestone (Member). Limestone reefs occurring near the village Sigugur (long. 109° 32' 52" E. lat. 7° 11' 45 " S). The limestone reaches a thickness of several hundreds of meters, and contains foraminifera Spiroclypeus, indicating a Te. age. They rest disconformably on the folded Eocene.

2. The Lutut Beds (member) (Loetoet lagen). Conglomerates with boulders of Nummulites and Discocyclina-limestones, sandstone, volcanic effusives, silicified slates, and coal. Intercalated in the conglomerates are beds of calcareous quartz-sandstones and black marly shales. The latter contains Lepidocyclina ferreroi, Miogypsina sp., Spiroclypeus cf. leupoldi, indicating a Te age for the formation. The beds occur in the Kali Lutut, at long. 110° 9' 27" E. lat. 7° 10' S.

The distribution of both basal formations is quite local.

The foraminifera contained in the upper, flyschlike part of the Merawu Beds indicate a T. f age: Katacycloclypeus annulatus Martin has been found in a single locality. The thickness of the beds cannot be ascertained because of the complicated folding. It must be at least several hundreds of metres.

They are conformably overlain by the Penjatan Beds.

Type locality: Kali Merawu, in the SE corner of sheet 66, long. 109° 43' 27" E - 109° 46' 52" E; lat. 7° 17' S - 7° 19' 30" S.

Geographical distribution: On sheet 66 in a strip of 3-5 km broad and about 50 km long running as a circle-segment from the SE to the NW corner of the sheet. In general, the beds occur in the Eastern part of the N. Serayu Mnts of N. Central Java, S. of Pekatongan-Semarang.

Diagnostic fossils: See text.

References: Bemmelen (R.W. van) (1941), pp. 20-24 Bemelen (R.W. van) (1949a), pp. 604, 605.

Bemmelen (R.W. van) (1949). The Geology of Indonesia, vol. IA, pp. 586, 590.

See: Globigerina Marl F'ormation (of B.P.M.).

Globigerina marls to a thickness of 200 m. At the base occurs a 5-10 m thick bed of diatomaceous marls.

According to van Bemmelen (1949, p. 590) the Mundu Formation may be correlated with the lower part of the Upper Kalibeng Formation, or with the lower part of the Damar Formation; the age would then be Upper Pliocene. No fossil evidence is offered.

The formation overlies conformably the Ledok Formation and is in turn overlain by the Turi Formation.

Type locality: Probably the river Mundu 100 km. SE of Rembang, N. Java.

Geographical distribution: Cepu anticlinorium probably also in south part of the adjacent Rembang anticlinorium, a range of hills between Demak, 30 km E of Semarang, to the island of Madura, over an E-W distance of about 200 km, with a greatest breadth of 60 km between Rembang and Cepu; N. Java.

Diagnostic fossils: Not mentioned.

Reference: Bemmelen (R.W. van) (1949b), pp. 33-34.

Verbeek (R.D.M.) & Fennema (R.) (1896). Geol. beschrijving van Java en Madoera, pp. 330-334, 903-907.

Limestones, clays, marls and sandstones with a neritic-littoral facies and intercalations of lignite.

Recent studies (Martin, 1915, 1931; Douville, 1912 Oppenoorth & Gerth, 1929) have established a subdivision in three Formations

The lowest formation is called the Axinea-beds (formation). They consist of sandstones with intercalations of lignite, overlain by littoral sandstones with numerous Pelecypods, among which Axinea dunkeri is prominent. The segments clearly represent a littoral facies with a transgressive tendency. The mineral composition, according to Oppenoorth, points to a derivation from an uplifted mainland with the same composition as the pre-Tertiary schists which occur in the Jiwo Hills nearby. Visible thickness 40 m.

The next formation is called the Djogjakartae-beds (formation) sandy marls, sands and clays, with many calcareous concretions, and a rich fauna of larger foraminifera and gastropoda. The characteristic fossil is Nummulites djogjakartae Martin. Thickness 60 m.

The top unit is called the Discocyclina beds (formation) consisting of marls and limestones without concretions, and with volcanic tuff-beds and arkose-sandstones increasingly intercalated towards the top, indicating a progressive tendency to regression. Discocyclina occurs so numerous that entire layers are composed of this foraminifer. Typical is D. omphalus. Thickness 200 m. The age of the entire group is Upper Eocene (Yaw stage of Burma. or Tb).

The Eocene layers are disconformably overlain by Miocene andesites, marls and coralline limestones of Burdigalian age.

See remarks from B.P.M.: Jiwo layers.

Type locality and geographic distribution: Village Kalisonogo near Nangulan, about 20 km West of Yogyakarta, Central Java.

A broadly anticlinal structure with the Eocene in the centre and Miocene on top is cut by the River (Kali) Progo and its tributaries. The outcrops of Eocene are mainly in the beds of the north flowing tributaries.

Diagnostic fossils: Axinea Beds: Axinea dunkeri Boettger; Cardita hillegondae Martin; Corbula semitorta Boettger; Arca molengraaffi Martin; Ancilla songgoensis Martin; Strepsidura songgoensis Martin; Cerithium songgoense Martin.

Numerous Gasteropoda, affiliated with those from the Eocene of the Paris basin.

Djogjakartae Beds: Nummulites djogjakartae Martin; N. vredenburgi Provale; N. bagelensis Verbeek; Discocyclina javana (Verbeek); D. dispansa (Sowerby).

Numerous gasteropoda described by Martin (1915, 1931).

Discocyclina Beds: Discocyclina javana (Verbeek); D. dispansa (Sowerby); D. fritschii (Douville); D. omphalus: Nummulites bagelensis (Verbeek); N. nanggulani (Verbeek); Pellatispira sp.

References: Martin (K.) (1915), pp. 107-222; Martin (K.) (1931), pp. 1-56; Douville (H.) (1912), pp. 279-294 Oppenoorth (W.F.F.) & Gerth (H.) (1929); Leupold (W.) & Vlerk (I.M. van der) (1931), p. 634; Bemmelen (R.W. van) (1949a), p. 105.

Martin (K.) (1887). Samml. geol. Reichsmus Leiden, series 1, vol. III, pp. 329-330.

Marine fossiliferous sediments found in a drill-hole near Ngembak near Semarang. C. Java, at a depth of 104-112 m. The molluscan fauna is regarded by Martin as belonging to the older Miocene.

The name is ill-defined and may be considered as obsolete.

Reference: Martin (K.) (1919), pp. 135, 145.

The Ngimbang beds are "defined" from the basal section of the 1974-1975 Pertamina Ngimbang-1 well drilled near the village of Ngimbang, about 55 kms east of Surabaya. This oil exploration well was the first to penetrate a significant thickness of this older Tertiary section, even though the facies was mostly monotonous mudstones and thin carbonate stringers of Oligocene, only possibly Eocene age. The term Ngimbang then came to be used for seismically mapped equivalents to this deep section acros east Java and the east Java Sea. With no alternative names available from the area, this term became entrenched even though it has always meant different things to different workers. Not even the top of the unit has been defined clearly (it may be a fault contact in the well), although in recent years it has been mostly defined on either the mid-Oligocene eustatic sequence boundary or the first strong seismic reflector, usually a Late Eocene carbonate (cf Bransden and Mathews 1992).

See: Southern Mountains Miocene.

See: Cimandiri Complex.