Sedimentary Environment of a Modern Carbonate Platform of Karimunjawa Islands, Central Java

Abstract Guided by conodont biostratigraphy and unconformities observed in the field, stable carbon isotopic analysis (δ13Ccarb) was performed on 210 samples from Lower–Middle Ordovician (Tremadocian to Darriwilian) sections and wells in the Tarim Basin, NW China. The δ13C trend in the Tarim Basin sections has three distinct characteristics: (1) from the Tremadocian to the Floian, a positive shift from −1.9 ‰ to −0.2 ‰ is observed near the boundary between the Penglaiba Formation and the Yingshan Formation; (2) from the Floian to the Dapingian, a positive shift in δ13C from −3 ‰ to −0.7 ‰ occurred under large-scale sea-level rise and a change in the sedimentary environment from a restricted platform to an open platform. Changes in the conodont type are also observed in the Tabei region; and (3) from the Dapingian to the Darriwilian, δ13C first decreased and then increased, showing a negative shift at the Dapingian–Darriwilian boundary. During the Floian, δ13C decreased in the study area, while it first decreased and then increased in other regions, which may reflect local sea-level movements in response to isostatic crustal movements. Two types of positive shift were identified at the Floian–Dapingian boundary, which likely show the effects of local factors, including a disconformity, dolomitization, and platform restriction, superimposed on the global signal of the carbon isotope. Some conodont zonations and recurrent negative excursions in Tremadocian, Floian and Dapingian stages appear to be truncated by unconformities, which are accompanied by short-term subaerial exposure due to sea-level fall and local tectonic uplift.

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The problems of groundwater assessment in the volcanic-sedimentary environment of Central Java

Quarterly Journal of Engineering Geology and Hydrogeology ◽

10.1144/gsl.qjeg.1985.018.01.07 ◽

1985 ◽

Vol 18 (1) ◽

pp. 47-61 ◽

Cited By ~ 2

Author(s):

J. W. Lloyd ◽

R. H. Pim ◽

M. D. Watkins ◽

A. Suwara

Keyword(s):

Sedimentary Environment ◽

Central Java ◽

Groundwater Assessment

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Facies and Sedimentary Environment of the Late Cretaceous Units at Abegarm(Avaj) Area

Current World Environment ◽

10.12944/cwe.10.special-issue1.93 ◽

2015 ◽

Vol 10 (Special-Issue1) ◽

pp. 771-781 ◽

Cited By ~ 2

Author(s):

Ghodratollah Mohammadi ◽

Massomeh Shirzad ◽

Ali Ashofteh

Keyword(s):

Late Cretaceous ◽

Upper Cretaceous ◽

Carbonate Platform ◽

Sedimentary Environment ◽

North West ◽

Microscopic Studies ◽

Marine Facies

An investigation was made on the facies and sedimentary environment of upper cretaceous rocks at north west of Abegarm(Avaj) area. This study has also covered carving lime sediments mainly being micritic and sparits with fossil(bioclast) markings, such as: Echinoderm, alga, lamelibransch, brachiopodo and berizoa. Field and microscopic studies led to recognition and separation of 10 carbonate and carving facies as follow: Group of open marine facies that include 1- Bioclastic mudstone, 2- Bioclastic wackstone, 3- Bioclastic packstone, Group of barrier facies that include 4- Bioclastic grainstone, 5- Grainstone packstone, Group of lagoon facies that include 6- Bioclastic packstone, 7- Peloid wackstone Group of continental facies that include, 8- Litharenite, 9- Sublitharenite and 10- Gerywacki. By interpretation and analysis of these microfacies and their related environment we shall be able to recognize the old geographical(palaeobiogeographic) condition in this region which has proven to have been a ramp type carbonate platform with a nearly uniform slope(homodinal ramp).

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Regional Distribution of Hazardous Elements in Late Permian Coal Southern Sichuan, China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.868.370 ◽

2013 ◽

Vol 868 ◽

pp. 370-373

Author(s):

Yang Bing Luo

Keyword(s):

Carbonate Platform ◽

Sedimentary Environment ◽

Regional Distribution ◽

Sedimentary Facies ◽

Late Permian ◽

Average Value ◽

Hazardous Elements ◽

Marine Carbonate ◽

Permian Coal ◽

Chinese Coal

In this paper, the regional distribution of six hazardous elements (S, Cl, Hg, Se, F and As) in Late Permian coal in southern Sichuan, China, is discussed based on the differences of the sedimentary environment. Based on the different sedimentary facies, the sedimentary environment of the southern Sichuan coal basin can be divided into three areas: fluvial or swamp (AreaI), tidal flat (AreaII) and marine carbonate platform (Area III). The content of F, Hg, Cl and Se is lower in the entire southern Sichuan coal field as compared to the average value of these hazardous elements in Chinese coal. The element S is concentrated in coal in Area III and the upper part of Area II. The element As is concentrated in coal in the upper part of Area II.

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Multiple Influences of Paleogeography, Sequence Stratigraphy, and Fold Structure on Coalbed Methane Accumulation in the Lopingian (Late Permian) of Junlian Coalfield, SW China

Geofluids ◽

10.1155/2021/3401273 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17

Author(s):

Xiangdong Gao ◽

Wuzhong Li ◽

Yiming Yang ◽

Kaigui Yin ◽

Shihao Zhou

Keyword(s):

Sequence Stratigraphy ◽

Coalbed Methane ◽

Carbonate Platform ◽

Sedimentary Environment ◽

Tidal Flats ◽

Gas Content ◽

Coal Seams ◽

Third Order ◽

Fold Structure ◽

Exploration And Development

Junlian coalfield is one of the main targets for coalbed methane (CBM) exploration and development in the southwest China. Based on field geological survey, core observation, gas content statistics, coal maceral composition, vitrinite reflectance ( R O ), proximate analysis and trace element test, lithological types, lithofacies, sedimentary environment, and structural analysis, this research established the sequence stratigraphy frame, revealed the plane distribution characteristics of sedimentary facies, and defined CBM accumulation mode. The results show that six rock types were identified and further subdivided into twenty lithofacies types. Four types of sedimentary systems such as alluvial plains, delta, lagoon-tidal flat, and carbonate platform were summarized according to their combination characteristics. Additionally, 12-14 fourth-order sequences and three third-order sequences CSI, CSII, and CSIII were divided, and a sequence stratigraphic framework of the Lopingian coal-bearing series was established. Among them, the features of third-order sequence CSIII paleogeography from west to east are alluvial plains, deltas, lagoon-tidal flats, and limited carbonate platforms. Thick coal seams are mainly developed in the sedimentary environment of tidal flats, delta plains, and floodplains behind banks. Closely related to coal seam thickness, gas contents of Lopingian coal seams are generally higher than 8 m3/t, except the low level in northwest and partial denudation areas. CBM accumulation is significantly controlled by the fold structure, and the hydraulic plugging effect makes the syncline core favorable for CBM accumulation. Furthermore, favorable geostress conditions enable the secondary anticline to become a favorable area for CBM accumulation when the sealing conditions are better. This research will provide a theoretical guide for the exploration and development of CBM in the study area.

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Biostratigraphy and microfacies of the pelagic carbonate formations in the Yavorets section (Tithonian–Berriasian), Western Balkan Mts, Bulgaria

Geologica Balcanica ◽

10.52321/geolbalc.48.2.51 ◽

2019 ◽

Vol 48 (2) ◽

pp. 51-73

Author(s):

Silviya Petrova ◽

Elena Koleva-Rekalova ◽

Daria Ivanova ◽

Iskra Lakova

Keyword(s):

Carbonate Platform ◽

Sedimentary Environment ◽

The West ◽

Regional Correlation ◽

Vertical Distributions ◽

Lower Berriasian ◽

Carbonate Formations ◽

Shallow Carbonate Platform ◽

Channel Deposits ◽

New Evidence

Calpionellid study has provided new evidence of early and late Tithonian age of the top of the Gintsi Formation, and of late Tithonian and early Berriasian age of the Glozhene Formation in the Yavorets section (Western Balkan Mts, Bulgaria). The calpionellid Chitinoidella, Praetintinnopsella, Crassicollaria, and Calpionella zones have been documented in successive order. Three calcareous dinocyst zones – Colomisphaera tenuis, Colomisphaera fortis and Stomiosphaerina proxima, have been determined in this lower Tithonian to lower Berriasian interval. From the base upwards, the following microfacies have been recognized: Saccocoma (Gintsi Formation, lower and upper Tithonian), Globochaete alpina, and calpionellid (Glozhene Formation, upper Tithonian and lower Berriasian). The base of the Berriasian has been traced at the explosion of the uniformly shaped spherical variety of Calpionella alpina. Evolutionary lineages of species of the genus Calpionella are discussed, as well as the vertical distributions and abundance peaks of crassicollarians. The calpionellid zones described herein are correlated with coeval zonations from the Western, Central and Eastern Tethyan domains. The regional correlation with previously studied sections of Tithonian/Berriasian pelagic carbonates in the Western Balkan Mts revealed a transition to hemipelagic deposition of the limestone-marl succession of the Salash Formation and/or sandstone accumulation during the middle to late Berriasian (Elliptica and Simplex calpionellid subzones) due to unstable conditions of the sedimentary environment. From the west to the east in the Western Balkan Unit (i.e., from the Rosomač section in eastern Serbia to the Sarbenitsa, Bov and Yavorets sections in the Iskar River Valley area), there is a trend of slight progressive deepening of the basin. This is manifested in the occurrence of redeposited shallow-carbonate-platform microfossils in the west to greater thickenesses of the Gintsi and Glozhene formations and occurrence of sandstone channel deposits in the east.

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Benthic foraminiferal zonation in deep-water carbonate platform margin environments, northern Little Bahama Bank

Journal of Paleontology ◽

10.1017/s0022336000058819 ◽

1988 ◽

Vol 62 (01) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Ronald E. Martin

Keyword(s):

Deep Water ◽

Benthic Foraminifera ◽

Carbonate Platform ◽

Sedimentary Facies ◽

Depositional Environments ◽

Near Surface ◽

Sediment Gravity Flows ◽

Gravity Flows ◽

Platform Margin ◽

Water Carbonate

The utility of benthic foraminifera in bathymetric interpretation of clastic depositional environments is well established. In contrast, bathymetric distribution of benthic foraminifera in deep-water carbonate environments has been largely neglected. Approximately 260 species and morphotypes of benthic foraminifera were identified from 12 piston core tops and grab samples collected along two traverses 25 km apart across the northern windward margin of Little Bahama Bank at depths of 275-1,135 m. Certain species and operational taxonomic groups of benthic foraminifera correspond to major near-surface sedimentary facies of the windward margin of Little Bahama Bank and serve as reliable depth indicators. Globocassidulina subglobosa, Cibicides rugosus, and Cibicides wuellerstorfi are all reliable depth indicators, being most abundant at depths >1,000 m, and are found in lower slope periplatform aprons, which are primarily comprised of sediment gravity flows. Reef-dwelling peneroplids and soritids (suborder Miliolina) and rotaliines (suborder Rotaliina) are most abundant at depths <300 m, reflecting downslope bottom transport in proximity to bank-margin reefs. Small miliolines, rosalinids, and discorbids are abundant in periplatform ooze at depths <300 m and are winnowed from the carbonate platform. Increased variation in assemblage diversity below 900 m reflects mixing of shallow- and deep-water species by sediment gravity flows.

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