Cambrian Ordovician sedimentary facies and its evolution in Tadong area

In order to clarify the sedimentary development law under the Cambrian Ordovician regional stratigraphic framework in Tadong area, and lay a theoretical foundation for further oil and gas exploration in the study area. The distribution, characteristics and evolution of main sedimentary facies belts of Cambrian Ordovician are studied by means of drilling core observation, cast thin section identification, logging curve feature analysis, seismic profile and well connection profile. The results show that the Cambrian middle lower Ordovician in Tadong area is equivalent to a second-order sequence and can be further divided into 12 thirdorder sequences. Each third-order sequence is mainly composed of transgressive and highstand tracts. Carbonate platform margin beach facies and Reef (mound) beach complex facies are favorable reservoir development facies belts in this area; Under the regional stratigraphic framework, three types of sedimentary facies can be identified in Cambrian Ordovician, and a total of 10 subfacies are developed; The evolution of sedimentary facies is mainly controlled by the rise and fall of sea level, which is characterized by the migration of platform margin facies and the change of platform facies.

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Distribution Regularity of the Ordovician Reef-Bank Reservoir inside Sequence Stratigraphic Framework in Central Tarim Basin

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.484-485.612 ◽

2014 ◽

Vol 484-485 ◽

pp. 612-615

Author(s):

Feng Zhu

Keyword(s):

Tarim Basin ◽

Carbonate Platform ◽

Late Ordovician ◽

Third Order ◽

Sequence Stratigraphic ◽

Stratigraphic Framework ◽

Platform Margin ◽

Carbonate Platform Margin ◽

Organic Reef ◽

Integrated Study

Based on the integrated study of the outcrops, the seismic, drilling and logging data of Lianglitage formation in central Tarim Basin, the sequence stratigraphic framework of the platform margin is built, and the Lianglitage formation is divided into 3 third-order sequences. The vertical pattern and lateral distribution for carbonate reef-bank reservoir in sequence stratigraphic framework are analyzed. The reef-bank reservoir mainly developed in highstand system tract of sequence Ssq2, and distributed along the carbonate platform margin of the Middle-Late Ordovician in central Tarim Basin. The mudstone mound, organic reef, granule bank are vertically stacked. Laterally, the area of well shun3-shun4-shun2-shun6 are characterized by multiphase bank reservoir overlapping, and the area of well TZ82-TZ44 - TZ161-TZ24 - TZ26 are characterized by multiphase organic reef and bank overlapping. The reef-bank complexes in sequence Ssq2 are the main targets of exploration in central Tarim Basin.

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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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GINSBURG, R. N. (ed.) 2000. Subsurface Geology of a Prograding Carbonate Platform Margin, Great Bahama Bank: Results of the Bahamas Drilling Project. SEPM Special Publication no. 70. vii+271 pp. Tulsa: SEPM (Society for sedimentary Geology). Price US $65.00 (non-members), US $40.00 (members), US $30.00 (special student price), plus shipping and handling; hard covers. ISBN 1 56576 077 8. Geol. Mag. 139, 2002, DOI: 10.1017/S0016756802256514

Geological Magazine ◽

10.1017/s0016756802256514 ◽

2002 ◽

Vol 139 (01) ◽

Author(s):

Martyn Pedley

Keyword(s):

Carbonate Platform ◽

The Bahamas ◽

Great Bahama Bank ◽

Subsurface Geology ◽

Special Publication ◽

Platform Margin ◽

Carbonate Platform Margin ◽

Drilling Project

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About this title - Seismic Characterization of Carbonate Platforms and Reservoirs

Geological Society London Special Publications ◽

10.1144/sp509 ◽

2021 ◽

Vol 509 (1) ◽

pp. NP-NP

Author(s):

J. Hendry ◽

P. Burgess ◽

D. Hunt ◽

X. Janson ◽

V. Zampetti

Keyword(s):

Seismic Data ◽

Oil And Gas ◽

Carbonate Platform ◽

Carbonate Platforms ◽

Oil And Gas Exploration ◽

Seismic Modelling ◽

Flow Units ◽

Development Data ◽

Seismic Characterization

Modern seismic data have become an essential toolkit for studying carbonate platforms and reservoirs in impressive detail. Whilst driven primarily by oil and gas exploration and development, data sharing and collaboration are delivering fundamental geological knowledge on carbonate systems, revealing platform geomorphologies and how their evolution on millennial time scales, as well as kilometric length scales, was forced by long-term eustatic, oceanographic or tectonic factors. Quantitative interrogation of modern seismic attributes in carbonate reservoirs permits flow units and barriers arising from depositional and diagenetic processes to be imaged and extrapolated between wells.This volume reviews the variety of carbonate platform and reservoir characteristics that can be interpreted from modern seismic data, illustrating the benefits of creative interaction between geophysical and carbonate geological experts at all stages of a seismic campaign. Papers cover carbonate exploration, including the uniquely challenging South Atlantic pre-salt reservoirs, seismic modelling of carbonates, and seismic indicators of fluid flow and diagenesis.

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The Sedimentary Facies and Evolution Characteristics of the Middle and Deep Strata in the Nanpu No. 3 Structural Area

Frontiers in Earth Science ◽

10.3389/feart.2021.703070 ◽

2021 ◽

Vol 9 ◽

Author(s):

Hui Zhang ◽

Zhiqin Lan ◽

Xiaoyan Li ◽

Xinglong Huang

Keyword(s):

Shallow Lake ◽

Oil And Gas ◽

Sedimentary Facies ◽

Seismic Profile ◽

Tectonic Activity ◽

Lake Basin ◽

Braided River ◽

Break Zone ◽

Sedimentary System ◽

Deep Strata

In this study, due to the inconsistencies in the understanding of the sedimentary types in the second section of the Dongying Formation (Ed2) and the third section of the Shahejie Formation (Es3) in the middle and deep strata of Nanpu No. 3 structural area, the depositional characteristics of the deep braided river delta, fan delta, deep-water slump turbidite fan, and coastal and shallow lake in the Nanpu No. 3 structural area were examined in-depth. The investigations were begun based on the descriptions and observations of core samples obtained from eight cored wells in the study area, in combination with seismic, well logging, and rock ore data. The results revealed that the sources of the material in the study area originated from the Shaleitian salient in the southwest direction. It was determined that the fan deltas and the shallow lake sedimentary system had developed during the SQ1 sequence and SQ2 sequence periods. The braided river deltas and the shallow lake and turbidite sedimentary system with multi-stage superposition had developed during the SQ3 to SQ7 sequence periods, and their distribution range had been controlled by the structural background of the gentle slope zone of the lake basin. On that basis, a sequence deposition filling model controlled by a slope break zone in the middle and deep strata of the Nanpu No. 3 structural area was established in this study starting from the typical seismic profile, in which such factors as the tectonic activity characteristics, lake basin boundary shape, water depths, and so on, were comprehensively considered. The goal of this research investigation was to provide beneficial information for oil and gas explorations in similar areas.

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