The upper Miocene Deurne Member of the Diest Formation revisited: unexpected results from the study of a large temporary outcrop near Antwerp International Airport, Belgium

A 5.50 m thick interval of fossiliferous intensely bioturbated heterogenous glauconiferous sand of the upper Miocene Diest Formation is documented from a very large temporary outcrop just southeast of Antwerp International Airport (northern Belgium), allowing to observe lateral variations over several hundreds of meters and to collect many vertebrate and invertebrate fossils. This paper documents observations on lithology, sedimentary and post-sedimentary structures, and discusses the results of the multi-proxy analyses of the sediment (granulometry, glauconite content, clay mineralogy, Fe content and Fe3+/Fe2+ ratios), the interpretation of the trace fossil assemblage and the sedimentary structures as well as of the large-scale samplings of micro-, meso- and macrofossils. We evidence that the Diest Formation in the Antwerp area consists of two different lithological entities, and that this twofold character can be extrapolated to all previously recorded Deurne Member outcrops. A revised lithostratigraphic scheme for the Diest Formation in the Antwerp area is proposed, with the new Borsbeek member at the base and a redefined Deurne Member at the top.

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Asteriacites and other trace fossils from the Po Formation (Visean–Serpukhovian), Ganmachidam Hill, Spiti Valley (Himalaya) and its paleoenvironmental significance

Geologica Carpathica ◽

10.1515/geoca-2017-0030 ◽

2017 ◽

Vol 68 (5) ◽

pp. 464-478 ◽

Cited By ~ 2

Author(s):

Birendra P. Singh ◽

Om N. Bhargava ◽

Radek Mikuláš ◽

Subhay K. Prasad ◽

Garry Singla ◽

...

Keyword(s):

Trace Fossils ◽

Trace Fossil ◽

Fossil Assemblage ◽

Sedimentary Structures ◽

The Village ◽

The Himalaya ◽

Open Shelf

Abstract An assemblage of trace fossils comprising Asteriacites stelliformis, A. quinquefolius, Biformites insolitus, Helminthoidichnites? isp., Lingulichnus isp., Lockeia siliquaria, Palaeophycus tubularis, Planolites isp., Protovirgularia isp. A, Protovirgularia isp. B, Protovirgularia isp. C, Psammichnites isp., Rusophycus isp., and Treptichnus isp. from the Po Formation (Visean-Serpukhovian) exposed along the base of Ganmachidam Hill near the village of Chichong, Spiti Valley in the Himalaya, is described. Storm beds (tempestites) are highly bioturbated. Sedimentary structures such as hummocky cross-stratification (HCS), low-angle planar and trough cross beds, and shallow, slightly asymmetrical gutter casts are observed. The overall trace fossil assemblage indicates the presence of upper shoreface to lower shoreface Cruziana ichnofacies of an open shelf.

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Lithostratigraphy of the Kweekvlei Formation (Witteberg Group), Cape Supergroup

South African Journal of Geology ◽

10.25131/gssajg.120.3.421 ◽

2017 ◽

Vol 120 (3) ◽

pp. 421-432 ◽

Cited By ~ 2

Author(s):

C. Browning ◽

M. Reid

Keyword(s):

South Africa ◽

Transition Zone ◽

Distal Part ◽

Vascular Plant ◽

Trace Fossil ◽

Plant Debris ◽

Lower Carboniferous ◽

Fossil Assemblage ◽

Low Diversity ◽

Storm Wave

AbstractThe Lower Carboniferous, probably Tournaisian, Kweekvlei Formation is part of the Witteberg Group (Cape Supergroup) of South Africa. Together with the overlying Floriskraal Formation, it forms an upward-coarsening succession within the Lake Mentz Subgroup. Sedimentary features of the Kweekvlei Formation suggest deposition in a storm-wave dominated marine setting, within the storm-influenced, distal part of an offshore transition zone environment. This predominantly argillaceous formation preserves a low diversity trace fossil assemblage. Reworked vascular plant debris (including the problematic genus Praeramunculus sp.) and a shark spine have been reported for the Kweekvlei Formation. There are no known stratigraphic equivalents in South Africa.

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Mineral Exploration using CSAMT data: Application to Longmen region metallogenic belt, Guangdong Province, China

Geophysics ◽

10.1190/geo2012-0115.1 ◽

2013 ◽

Vol 78 (3) ◽

pp. B111-B119 ◽

Cited By ~ 28

Author(s):

Xiangyun Hu ◽

Ronghua Peng ◽

Guiju Wu ◽

Weiping Wang ◽

Guangpu Huo ◽

...

Keyword(s):

Large Scale ◽

Southern China ◽

Mineral Exploration ◽

Geochemical Data ◽

Data Application ◽

Metallogenic Belt ◽

Fe Content ◽

Geophysical Surveys ◽

Occam’S Inversion ◽

Integrated Interpretation

A controlled-source audio-frequency magnetotelluric (CSAMT) survey has been carried out to investigate potential iron (Fe) and polymetallic (Pb-Zn-Cu) deposits in Longmen region, which is one of the main metallogenic belts in southern China. Conducting geophysical surveys in this area is quite difficult due to mountainous terrain, dense forest, and thick vegetation cover. A total of 560 CSAMT soundings were recorded along twelve surveying lines. Two-dimensional Occam’s inversion scheme was used to interpret these CSAMT data. The resulting electric resistivity models showed that three large-scale highly conductive bodies exist within the surveying area. By integrated interpretation combined with available geologic, geophysical, and geochemical data in this area, three prospective mineral deposits were demarcated. Based on the CSAMT results, a borehole penetrating approximately 250-m depth was drilled at the location of 470 m to the northwest end of line 06, defined with a massive pyrite from the depth of 52–235 m with 7%–16% Fe content, as well as locally high-grade Pb-Zn- and Ag-Ti-bearing ores.

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Separation of Fe from Mn in the Cryogenian Sedimentary Mn Deposit, South China: Insights from Ore Mineral Chemistry and S Isotopes from the Dawu Deposit

Minerals ◽

10.3390/min11050446 ◽

2021 ◽

Vol 11 (5) ◽

pp. 446

Author(s):

Zhiming Xu ◽

Chengquan Wu ◽

Zhengwei Zhang ◽

Jinhong Xu ◽

Xiyao Li ◽

...

Keyword(s):

South China ◽

Large Scale ◽

Early Stage ◽

Sulfur Isotopes ◽

Mineral Chemistry ◽

Manganese Carbonate ◽

Separation Mechanism ◽

Geochemical Properties ◽

Stage Separation ◽

Fe Content

Manganese and Fe have similar geochemical properties in the supergene environment. Separation of Mn and Fe is an important process for the formation of high-grade sedimentary manganese deposits. Large-scale manganese carbonate deposits (total reserves of approximately 700 Mt) were formed during the interglacial of the Sturtian and Marinoan in South China. The orebodies are hosted in the black rock series at the basal Datangpo Formation of the Cryogenian period. The Fe contents in ores range from 1.15 to 7.18 wt.%, with an average of 2.80 wt.%, and the average Mn/Fe ratio is 8.9, indicating a complete separation of Mn and Fe during the formation of manganese ores. Here, we present element data of manganese carbonates and sulfur isotopes of pyrite from the Dawu deposit, Guizhou, China, aiming to investigate the separation mechanism of Mn and Fe and the ore genesis. The Fe in ores mainly occurs as carbonate (FeCO3) and pyrite (FeS2). The Mn, Ca, Mg and Fe exist in the form of isomorphic substitutions in manganese carbonate. The contents of FeCO3 in manganese carbonates are similar in different deposits, with averages of 2.6–2.8 wt.%. The whole-rock Fe and S contents have an obvious positive correlation (R = 0.69), indicating that the difference of whole-rock Fe content mainly comes from the pyrite content. The δ34SV-CDT of pyrite varies from 40.0 to 48.3‰, indicating that the pyrite formed in a restricted basin where sulfate supply was insufficient and the sulfate concentrations were extremely low. Additionally, the whole-rock Fe content is negatively correlated with the δ34S values of the whole-rock and pyrite, with correlation coefficients of −0.78 and −0.83, respectively. Two stages of separations of Mn and Fe might have occurred during the mineralization processes. The reduced seawater became oxidized gradually after the Sturtian glaciation, and Fe2+ was oxidized and precipitated before Mn2+, which resulted in the first-stage separation of Mn and Fe. The residual Mn-rich and Fe-poor seawater flowed into the restricted rift basin. Mn and Fe were then precipitated in sediments as oxyhydroxide as the seawater was oxidized. At the early stage of diagenesis, organic matter was oxidized, and manganese oxyhydroxide was reduced, forming the manganese carbonate. H2S was insufficient in the restricted basin due to the extremely low sulfate concentration. The Fe2+ was re-released due to the lack of H2S, resulting in the second-stage separation of Mn and Fe. Finally, the manganese carbonate deposit with low Fe and very high δ34S was formed in the restricted basin after the Sturtian glaciation.

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Three-dimensional visualized space and asset management system for large-scale airports: The case of Incheon International Airport

International Journal of Architectural Computing ◽

10.1177/1478077116663345 ◽

2016 ◽

Vol 14 (3) ◽

pp. 233-246 ◽

Cited By ~ 2

Author(s):

Eonyong Kim ◽

Soohoon Park

Keyword(s):

Asset Management ◽

Management System ◽

Large Scale ◽

Three Dimensional ◽

International Airport ◽

Asset Management System

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The Simulation of Large-Scale Sedimentary Structures

Computer Applications in the Earth Sciences - Computerized Basin Analysis ◽

10.1007/978-1-4615-2826-5_10 ◽

1993 ◽

pp. 131-144

Author(s):

P. A. Dowd

Keyword(s):

Large Scale ◽

Sedimentary Structures

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Facies Evaluation and Depositional Environments of Carbonates of the Bagh Group, Dhar District, Madhya Pradesh, India

Indian Association of Sedimentologists ◽

10.51710/jias.v38i1.154 ◽

2021 ◽

Vol 38 (1) ◽

pp. 33-40

Author(s):

Sreejita Chatterjee ◽

Dhiren Kumar Ruidas

Keyword(s):

Grain Size ◽

Large Scale ◽

Energy Condition ◽

Size Variation ◽

High Energy ◽

Depositional Environments ◽

Small Scale ◽

Peninsular India ◽

Sedimentary Structures ◽

Nodular Limestone

A significant event of marine transgression took place in Central India during Late Turonian-Coniacian. Fossiliferous marine succession of Bagh Group is one of the few carbonate successions exposed in peninsular India which was in focus of the current study for understanding this event. The signatures of this event were identified in the carbonate succession. The carbonates of Bagh Group are composed of two formations: the lower part is represented by Nodular limestone Formation which is overlain by Bryozoan limestone Formation at the top. On the basis of grain size variation and sedimentary structures, the Nodular limestone is divisible into three facies: facies ‘A’, facies ‘B’ and facies ‘C’. A hardground exists between facies B and facies C. Lack of sedimentary structures and high mud content indicates low energy depositional setting for the Nodular limestone Formation. Similarly, Bryozoan limestone Formation is divisible into five facies: facies ‘D’, facies ‘E’, facies ‘F’, facies ‘G’ and facies ‘H’ based on grain size variation and sedimentary structures. All of these five facies are fossiliferous. Glauconites are present within facies ‘G’ and have two modes of occurrence - as infilling within Bryozoan limestone and as altered feldspar. Presence of both small- and large-scale cross-stratification in Bryozoan limestone with lesser mud content are indicative of high energy shallow marine conditions. Large-scale cross-stratifications are possibly representing tidal bars while the small scale cross stratifications are formed in inter bar setting. Presence of reactivation surfaces within facies ‘E’ also supports their tidal origin. Increase in depositional energy condition is also evident from dominated by packstone facies.

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CHONDRITES-CLADICHNUS ICHNOCOENOSIS FROM THE DEEP-SEA DEPOSITS OF PIERFRANCESCO (CRETACEOUS; ITALY): OXYGEN- OR NUTRIENT-LIMITED?

RIVISTA ITALIANA DI PALEONTOLOGIA E STRATIGRAFIA ◽

10.54103/2039-4942/16972 ◽

2022 ◽

Vol 128 (1) ◽

Author(s):

ANDREA BAUCON ◽

GIROLAMO LO RUSSO ◽

CARLOS NETO DE CARVALHO ◽

FABRIZIO FELLETTI

Keyword(s):

Late Cretaceous ◽

Deep Sea ◽

Trace Fossils ◽

Northern Apennines ◽

Trace Fossil ◽

Ecological Succession ◽

Rhythmic Pattern ◽

Low Oxygen ◽

Fossil Assemblage

The Italian Northern Apennines are acknowledged as the place where ichnology was born, but there is comparatively little work about their ichnological record. This study bridges this gap by describing two new ichnosites from the locality of Pierfrancesco, which preserve an abundant, low-disparity trace-fossil assemblage within the Late Cretaceous beds of the M. Cassio Flysch. Results show that lithofacies and ichnotaxa are rhythmically organized. The base of each cycle consists of Megagrapton-bearing calciclastic turbidites, which are overlain by marlstone beds with an abundant, low-disparity assemblage of trace fossils. This includes Chondrites intricatus, C. patulus, C. targionii, C. recurvus and Cladichnus fischeri. The cycle top consists of mudstones with no distinct burrows. The rhythmic pattern of Pierfrancesco reflects a deep-sea ecological succession, in which species and behaviour changed as turbidite-related disturbances altered the seafloor. This study opens the question of whether the Chondrites-Cladichnus ichnocoenosis represents low-oxygen or nutrient-poor settings.

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