Deep-water facies and depositional setting of the lower Conception Group (Hadrynian), southern Avalon Peninsula, Newfoundland

S. Gardiner; R. N. Hiscott

doi:10.1139/e88-151

Deep-water facies and depositional setting of the lower Conception Group (Hadrynian), southern Avalon Peninsula, Newfoundland

Canadian Journal of Earth Sciences ◽

10.1139/e88-151 ◽

1988 ◽

Vol 25 (10) ◽

pp. 1579-1594 ◽

Cited By ~ 19

Author(s):

S. Gardiner ◽

R. N. Hiscott

Keyword(s):

Deep Water ◽

Bottom Current ◽

Small Scale ◽

Volcanic Arcs ◽

Submarine Fans ◽

Basin Floor ◽

Volcanic Islands ◽

Depositional Setting ◽

Avalon Peninsula ◽

Water Facies

The lower part of the Hadrynian Conception Group is exposed in coastal outcrops near Holyrood Pond, St. Mary's Bay. Deep-water sediments of the Mall Bay Formation (>800 m) are overlain by glaciogenic debris flows of the Gaskiers Formation (250–300 m) and then by renewed turbidite deposition in the lower part of the Drook Formation (1000 m examined; formation thickness 1500 m). The main facies in the Mall Bay and Drook formations are thinly to very thickly bedded sand stone–mudstone couplets (turbidites), amalgamated in the thicker and coarser beds, and graded-stratified siltstones–mudstones. These are interpreted as deposits on an extensive basin floor and on the lower and middle parts of small-scale submarine fans that prograded from fringing volcanic islands. Paleocurrent data indicate a complex paleogeography dominated by active volcanic islands, probably like some modern volcanic arcs. The Gaskiers Formation was generated by glaciation of these islands.The Malll Bay Formation contains lenticular and wavy bedded siltstones–mudstones interpreted as the deposits of bottom currents, perhaps flowing parallel to the contours of the volcanic islands. In Phanerozoic sediments, bottom-current deposits in this setting would probably be thoroughly bioturbated.

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Distinguishing between Deep-Water Sediment Facies: Turbidites, Contourites and Hemipelagites

Geosciences ◽

10.3390/geosciences10020068 ◽

2020 ◽

Vol 10 (2) ◽

pp. 68 ◽

Cited By ~ 13

Author(s):

Dorrik Stow ◽

Zeinab Smillie

Keyword(s):

Deep Water ◽

Large Scale ◽

Tectonic Setting ◽

Regional Scale ◽

Small Scale ◽

Physical Parameters ◽

Sedimentary Characteristics ◽

Natural Systems ◽

Facies Types ◽

Water Facies

The distinction between turbidites, contourites and hemipelagites in modern and ancient deep-water systems has long been a matter of controversy. This is partly because the processes themselves show a degree of overlap as part of a continuum, so that the deposit characteristics also overlap. In addition, the three facies types commonly occur within interbedded sequences of continental margin deposits. The nature of these end-member processes and their physical parameters are becoming much better known and are summarised here briefly. Good progress has also been made over the past decade in recognising differences between end-member facies in terms of their sedimentary structures, facies sequences, ichnofacies, sediment textures, composition and microfabric. These characteristics are summarised here in terms of standard facies models and the variations from these models that are typically encountered in natural systems. Nevertheless, it must be acknowledged that clear distinction is not always possible on the basis of sedimentary characteristics alone, and that uncertainties should be highlighted in any interpretation. A three-scale approach to distinction for all deep-water facies types should be attempted wherever possible, including large-scale (oceanographic and tectonic setting), regional-scale (architecture and association) and small-scale (sediment facies) observations.

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Linked lowstand delta to basin-floor fan deposition, offshore East Kalimantan: an analogue for deep-water reservoir systems

10.29118/ipa.1993.05.g.147 ◽

2018 ◽

Author(s):

A.P. Ruzuar

Keyword(s):

Deep Water ◽

Water Reservoir ◽

East Kalimantan ◽

Reservoir Systems ◽

Basin Floor

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Mudrock Microstructure: A Technique for Distinguishing between Deep-Water Fine-Grained Sediments

Minerals ◽

10.3390/min11060653 ◽

2021 ◽

Vol 11 (6) ◽

pp. 653

Author(s):

Shereef Bankole ◽

Dorrik Stow ◽

Zeinab Smillie ◽

Jim Buckman ◽

Helen Lever

Keyword(s):

Grain Size ◽

Deep Water ◽

Sedimentary Facies ◽

X Ray Diffraction ◽

Weak Current ◽

Large Area ◽

Fine Grained ◽

Mean Size ◽

The Mean ◽

Water Facies

Distinguishing among deep-water sedimentary facies has been a difficult task. This is possibly due to the process continuum in deep water, in which sediments occur in complex associations. The lack of definite sedimentological features among the different facies between hemipelagites and contourites presented a great challenge. In this study, we present detailed mudrock characteristics of the three main deep-water facies based on sedimentological characteristics, laser diffraction granulometry, high-resolution, large area scanning electron microscopy (SEM), and the synchrotron X-ray diffraction technique. Our results show that the deep-water microstructure is mainly process controlled, and that the controlling factor on their grain size is much more complex than previously envisaged. Retarding current velocity, as well as the lower carrying capacity of the current, has an impact on the mean size and sorting for the contourite and turbidite facies, whereas hemipelagite grain size is impacted by the natural heterogeneity of the system caused by bioturbation. Based on the microfabric analysis, there is a disparate pattern observed among the sedimentary facies; turbidites are generally bedding parallel due to strong currents resulting in shear flow, contourites are random to semi-random as they are impacted by a weak current, while hemipelagites are random to oblique since they are impacted by bioturbation.

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Autogenic influence on the morphology of submarine fans: an approach from 3D physical modelling of turbidity currents

Brazilian Journal of Geology ◽

10.1590/2317-4889201720170066 ◽

2017 ◽

Vol 47 (3) ◽

pp. 345-368

Author(s):

Cristiano Fick ◽

Rafael Manica ◽

Elírio Ernestino Toldo Junior

Keyword(s):

Deep Water ◽

Physical Modelling ◽

Sediment Concentration ◽

Experimental Series ◽

Turbidity Currents ◽

Geometrical Parameters ◽

Submarine Fans ◽

Relative Standard ◽

Length Width ◽

Depositional Evolution

ABSTRACT: Autogenic controls have significant influence on deep-water fans and depositional lobes morphology. In this work, we aim to investigate autogenic controls on the topography and geometry of deep-water fans. The influence of the sediment concentration of turbidity currents on deep-water fans morphology was also investigated. From the repeatability of 3D physical modeling of turbidity currents, two series of ten experiments were made, one of high-density turbidity currents (HDTC) and another of low-density turbidity currents (LDTC). All other input parameters (discharge, sediment volumetric concentration and grain size median) were kept constant. Each deposit was analyzed from qualitative and quantitative approaches and statistical analysis. In each experimental series, the variability of the morphological parameters (length, width, L/W ratio, centroid, area, topography) of the simulated deep-water fans was observed. Depositional evolution of the HDTC fans was more complex, showing four evolutionary steps and characterized by the self-channelizing of the turbidity current, while LDTC fans neither present self-channelizing, nor evolutionary steps. High disparities on the geometrical parameters of the fans, as characterized by the elevated relative standard deviation, suggest that autogenic controls induced a stochastic morphological behaviour on the simulated fans of the two experimental series.

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