The Campbellton Formation, New Brunswick, Canada: paleoenvironments in an important Early Devonian terrestrial locality

2011 ◽  
Vol 48 (12) ◽  
pp. 1561-1580 ◽  
Author(s):  
Kirsten Kennedy ◽  
Martin R. Gibling
Keyword(s):  
Debris Flows ◽  
River System ◽  
Braided River ◽  
Early Devonian ◽  
Fine Grained ◽  
Lacustrine Deposits ◽  
Facies Associations ◽  
Aquatic Vertebrates ◽  
Near Shore ◽  
Lacustrine Facies

Strata of the Campbellton Formation, nearly 1 km-thick and known for its diverse fossil assemblage of early plants, arthropods, and fish, can be divided into six facies associations: (1) restricted lacustrine, (2) marginal lacustrine, (3) near-shore lacustrine, (4) coastal-deltaic, (5) sandy to gravelly alluvial plain, and (6) gravelly proximal alluvial environments. Lacustrine deposits with restricted circulation, due to depth or stagnation, are fine-grained with preserved organic material. The marginal lacustrine association consists of massive siltstone and very fine sandstone, interbedded with conglomerate. The latter are interpreted to have shed from older volcanic units forming the basin walls. The near-shore lacustrine association is characterized by rippled sandstone with microbialites. Alluvial strata include interbedded imbricate to nonimbricate conglomerate, trough cross-stratified sandstone, and barren to plant-bearing siltstone. Rare exposures of thickly bedded imbricate to weakly imbricated cobble–boulder conglomerate with sandy plant-bearing lenses are interpreted as products of hyperconcentrated debris flows. In the western belt, a braided-fluvial system had paleocurrents flowing WNW. Coastal-deltaic deposits west of the fluvial outcrops, containing aquatic vertebrates and invertebrates, had paleocurrents flowing ESE, suggesting a confined body of fresh or brackish water. In lower parts of the eastern belt, lacustrine facies are prevalent, representing a large open lake. Alluvial facies dominate upper parts of the formation, representing an eastward-flowing axial braided river system, with proximal alluvium shed transversely from the basin margins. Although most strata have a volcanic provenance, only one outcrop in the lacustrine beds shows evidence of active volcanism during deposition of the Campbellton Formation.

scholarly journals Sedimentary facies analysis of the fluvial systems in the Siwalik Group, Karnali River section, Nepal Himalaya, and their significance for understanding the paleoclimate and Himalayan tectonics

2016 ◽  
Vol 51 ◽  
pp. 11-26 ◽  
Author(s):  
Ashok Sigdel ◽  
Tetsuya Sakai
Keyword(s):  
River System ◽  
Precipitation Pattern ◽  
Braided River ◽  
River Section ◽  
Meandering River ◽  
Braided Rivers ◽  
Facies Associations ◽  
Siwalik Group ◽  
Himalayan Tectonics ◽  
Flood Flow

Fluvial sediments of the Siwalik successions in the Himalayan Foreland Basin are one of the most important continental archives for the history of Himalayan tectonics and climate change during the Miocene Period. This study reanalyzes the fluvial facies of the Siwalik Group along the Karnali River, where the large paleo-Karnali River system is presumed to have flowed. The reinterpreted fluvial system comprises fine-grained meandering river (FA1), flood-flow dominated meandering river with intermittent appearance of braided rivers (FA2), deep and shallow sandy braided rivers (FA3, FA4) to gravelly braided river (FA5) and finally debris-flow dominated braided river (FA6) facies associations, in ascending order. Previous work identified sandy flood-flow dominated meandering and anastomosed systems, but this study reinterprets these systems as a flood-flow dominated meandering river system with intermittent appearance of braided rivers, and a shallow sandy braided system, respectively. The order of the appearance of fluvial depositional systems in the Karnali River section is similar to those of other Siwalik sections, but the timing of the fluvial facies changes differs. The earlier appearance (3-4 Ma) of the flood-flow dominated meandering river system in the Karnali River section at about 13.5 Ma may have been due to early uplift of the larger catchment size of the paleo-Karnali River which may have changed the precipitation pattern i.e. intensification of the Indian Summer Monsoon. The change from a meandering river system to a braided river system is also recorded 1 to 3 Ma earlier than in other Siwalik sections in Nepal. Differential and diachronous activities of the thrust systems could be linked to change in catchment area as well as diachronous uplift and climate, the combination of which are major probable causes of this diachronity.

scholarly journals THE OCCURRENCE OF PALAEOZOIC CONGLOMERATIC ROCKS IN EAST JOHOR, PENINSULAR MALAYSIA

2015 ◽  
Vol 1 (2) ◽  
Author(s):  
Sugeng Sapto Surjono ◽  
Mohd Shafeea Leman ◽  
Kamal Roslan Mohamed ◽  
Che Aziz Ali
Keyword(s):  
Marine Environment ◽  
Debris Flows ◽  
Depositional Environment ◽  
River System ◽  
Peninsular Malaysia ◽  
Late Carboniferous ◽  
Braided River ◽  
Late Permian ◽  
Shallow Marine ◽  
Shallow Marine Environment

Conglomeratic rocks in East Johor are found in the separately three formations that are the Murau, Tanjung Leman and Linggiu Formations. The Murau Formation is characterized by cobble to boulder grained breccia with very angular to angular and disorganized clasts. It was deposited by fan-delta system in the sub-aerial to shallow marine environment. The Tanjung Leman Formation consists of pebble to cobble grained conglomerate with rounded to subrounded and organized clasts. It was deposited by braided river system in the sub-aerial environment. Both formations outcropped in eastern coastal of Johor. The rudaceous rocks of the Linggiu Formation consist of pebble to cobble-sized clasts with sub angular and disorganized texture. It present as subordinate rocks within sandstone dominant in the central part of East Johor and was deposited by debris flows in the shallow marine environment. All these rudaceous rocks were interpreted as Palaeozoic in age ranging from Late Carboniferous to Late Permian. Those rudaceous rocks indicated that since Late Carboniferous, palaeogeography of East Johor was a continent with subaerial to shallow marine depositional environment. Keywords: Conglomerate, Palaeozoic, East Johor, subaerial, shallow marine.

Characterizing heterogeneity in a glaciofluvial deposit using architectural elements, Limehouse, Ontario, Canada

2013 ◽  
Vol 50 (9) ◽  
pp. 911-929 ◽  
Author(s):  
J.M. Slomka ◽  
C.H. Eyles
Keyword(s):  
Late Quaternary ◽  
Coarse Grained ◽  
Paleoenvironmental Reconstruction ◽  
Braided River ◽  
Delta Front ◽  
Element Analysis ◽  
Alluvial Deposits ◽  
Fine Grained ◽  
Architectural Elements ◽  
Facies Associations

Major hydrocarbon and groundwater reservoirs are commonly hosted within coarse-grained alluvial deposits that contain a high degree of sedimentary heterogeneity. This paper presents a detailed characterization of the sedimentary heterogeneity of fluvial–deltaic deposits using architectural element analysis (AEA). Sedimentological data collected from outcrop faces exposing Late Quaternary glaciofluvial deposits in southern Ontario, Canada, is recorded in 31 sedimentary logs. These logs are used to identify nine different facies types, including gravel facies (Gm, Gp, Gt), sand facies (Sr, Sp, St, Ss), and fine-grained facies (Fl and Fd). Variations in facies associations and geometries are defined by five architectural elements (AEs): sand complex (SC), gravel sheet (GS), fine-grained sheet (FS), gravel foreset body (GFB), and concave fill (CF) elements. The spatial arrangement of bounding surfaces (first- to fifth-order) and AEs allows the classification of six EAs, which, in this study, are defined as the largest-scale architectural subunits that allow for architectural-based mapping over a large area. EAs delineated in this study are sandy braided-river (EA1), delta-front (EA2), gravelly braided-river to delta-top (EA3), delta-front to lacustrine (EA4), braided-river to deltaic (EA5), and sand-dominated fluvial (EA6). AEA is utilized here to capture three levels of heterogeneity, which allow detailed reservoir characterization based on geometric objects and can be readily used for computer-based modelling. Outcrop analogue studies such as this one provide insight to the geometries of more deeply buried coarse-grained deposits that form potential reservoirs and enhance paleoenvironmental reconstruction of subsurface alluvial deposits in Canada and elsewhere.

scholarly journals DEVELOPMENT OF A FLOOD RISK ASSESSMENT MODEL FOR A BRAIDED RIVER SYSTEM

2017 ◽  
pp. 25
Author(s):  
Mustafa Kemal Cambazoglu ◽  
Cheryl Ann Blain
Keyword(s):  
Risk Management ◽  
Flood Risk ◽  
Channel Model ◽  
River System ◽  
Flood Risk Management ◽  
High Flow ◽  
Water Levels ◽  
Pearl River ◽  
Braided River ◽  
River Channels

The aim of this study is to construct a modeling system that will assist flood risk management strategies in a coastal plain braided river system. The model configuration consists of a hydrodynamic model (ADCIRC) of the river basin that receives tidal forcing at the open boundary and river discharge forcing at upstream flux boundary. An unstructured mesh model resolving the Pearl River channels at higher resolution from the coastline to approximately 75km inland to upstream reaches of the river has been constructed. The modeling system produces water levels and currents throughout the Lower Pearl River Basin. Initial sensitivity analysis efforts on the channel model include consideration of low-flow, average-flow, and high-flow scenarios. Model results were found to be slightly sensitive to slope of river channels and bottom friction to control stability in predictions. The model results were shown to be highly sensitive to the bathymetry of the model that controls the discharge capacity of the narrow river channels and the channel model resulted in elevated currents and water levels under high flow conditions. A channel discharge capacity analysis was conducted and the results showed the need to construct a floodplain mesh around the channel model with more realistic bathymetry and topography so that the flooding scenarios could be modeled with wetting and drying capability of ADCIRC. An initial attempt to develop such a floodplain mesh has been made with preliminary results and more comprehensive validation of the developed floodplain modeling system will extend to reproducing events associated with the historical Hurricane Isaac that impacted the region in 2012. This modeling system will provide an important tool to decision makers that could be used in future flood risk management and mitigation efforts.

Electrical resistivity tomography investigations in the ufita Valley (southern Italy).

2008 ◽  
Vol 51 (1) ◽  
Author(s):  
A. Giocoli ◽  
C. Magrì ◽  
P. Vannoli ◽  
S. Piscitelli ◽  
E. Rizzo ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Southern Italy ◽  
Normal Fault ◽  
Fluvial Sediments ◽  
Resistivity Tomography ◽  
Fine Grained ◽  
Sedimentary Deposits ◽  
Lacustrine Deposits ◽  
Sedimentary Deposit

Several Electrical Resistivity Tomography (ERT) surveys have been carried out to study the subsurface structural and sedimentary settings of the upper Ufita River valley, and to evaluate their efficiency to distinguish the geological boundary between shallow Quaternary sedimentary deposits and clayey bedrock characterized by moderate resistivity contrast. Five shallow ERTs were carried out across a morphological scarp running at the foot of the northeastern slope of the valley. This valley shoulder is characterized by a set of triangular facets, that some authors associated to the presence of a SW-dipping normal fault. The geological studies allow us to interpret the shallow ERTs results obtaining a resistivity range for each Quaternary sedimentary deposit. The tomographies showed the geometrical relationships of alluvial and slope deposits, having a maximum thickness of 30-40 m, and the morphology of the bedrock. The resistivity range obtained for each sedimentary body has been used for calibrating the tomographic results of one 3560m-long deep ERT carried out across the deeper part of the intramountain depression with an investigation depth of about 170 m. The deep resistivity result highlighted the complex alluvial setting, characterized by alternating fine grained lacustrine deposits and coarser gravelly fluvial sediments.

Tectonic and geomorphic controls on the lacustrine deposits of the Neogene Vinchina basin, northwestern Argentina

2020 ◽  
Vol 90 (2) ◽  
pp. 250-267 ◽  
Author(s):  
Sergio A. Marenssi ◽  
Carlos O. Limarino ◽  
Laura J. Schencman ◽  
Patricia L. Ciccioli
Keyword(s):  
Water Depth ◽  
Drainage Basin ◽  
Low Frequency ◽  
Sedimentary Facies ◽  
Coarse Grained ◽  
Lacustrine Deposits ◽  
Facies Associations ◽  
Order Of Magnitude ◽  
Fluvial Sedimentation ◽  
The Individual

ABSTRACT Two episodes of lacustrine sedimentation, separated by an erosional surface and fluvial sedimentation, took place in the southern part of the broken foreland Vinchina basin (NW Argentina) between 11 and 5 Ma. The lacustrine deposits, 768 and 740 meters thick, are recorded in the upper part of the Vinchina Formation (“Vinchina lake”) and the lower part of the Toro Formation (“Toro Negro lake”) respectively. According to sedimentological features, four sedimentary facies associations (FAs) are recognized in the lacustrine deposits: 1) thinly laminated mudstones facies association (FA 1), 2) coarsening- and thickening-upward muddy to sandy cycles (FA 2), 3) medium- to coarse-grained sandstones (FA 3), and 4) mudstones, sandstones, and oolitic limestones (FA 4). Altogether, these facies correspond to ephemeral, shallow, lacustrine systems including saline mudflats. The total thickness of each lacustrine interval, the thickness of the individual cycles and their lithology, and the overall aggradational facies arrangement suggest that both lakes developed during underfilled stages of the basin. The coarsening-upward cycles can be regarded as lacustrine parasequences representing cyclic episodes of expansion and contraction of the lake, but unlike marine parasequences these cycles do not correlate to water depth. The development of lacustrine conditions and continuous base-level rise, together with the coeval southward-directed paleoflow indicators, suggest axial drainages and that the basin was externally closed (endorheic) at that time. The large thicknesses of each lacustrine interval also points to high accommodation in the southern part of the Vinchina basin during these times. Lake filling cycles are one order of magnitude thicker than lake depth, so we postulate that subsidence (tectonic) and rise of the spill point (geomorphology) increased accommodation but not water depth. Thus, unlike marine parasequences, the analyzed coarsening-upward cycles do not correlate to water depth, but rather they are controlled by more complex basinal accommodation processes. We hypothesize that the coeval uplift of the Umango and Espinal basement block to the south, coupled with the initial doming of the Sierra de Los Colorados to the east, may have generated the damming of the southward-directed drainage and a zone of maximum accommodation, then controlling the location of the two lakes and the preservation of their thick sedimentary records. Therefore, localized accommodation was enhanced by a combination of tectonic subsidence and topographic growth. The two lacustrine intervals and the intervening fluvial deposits record changing contributions from axial to transverse drainages and different cycles of closed and open conditions in the basin. A low-frequency, closed to open and back to closed (axial to transverse and return to axial drainage) basin evolution, is envisaged by the development of the two lakes (closed stages) and the erosional surface followed by the interval of fluvial sedimentation that separates them (open stage). In addition, several high-frequency lake fluctuations (expansion–contraction) are represented by the coarsening-upward cycles within each lacustrine interval. The thick lacustrine intervals and their intermediate incision surfaces record cyclic filling and re-excavation stages and localized episodes of increased subsidence in the Vinchina basin, which seem to be a common feature of tectonically active broken foreland basins.

scholarly journals Lithostratigraphy and late Cenozoic fluvial styles of Siwalik Group along Kankai River section, East Nepal Himalaya

1970 ◽  
Vol 12 ◽  
pp. 63-74 ◽  
Author(s):  
Prakash Das Ulak
Keyword(s):  
Grain Size ◽  
River Section ◽  
Late Cenozoic ◽  
Nepal Himalaya ◽  
Fine Grained ◽  
The North ◽  
Lithostratigraphic Units ◽  
Facies Associations ◽  
Siwalik Group ◽  
Southern Flank

This paper describes on lithostratigraphy as well as evolution of the fluvial styles in late Cenozoic Siwalik Group along the Kankai River section of east Nepal Himalaya. The Siwalik Group lies on the southern flank of the Himalaya, is composed of molasse sediments, which were derived from the rising Himalaya in the north. The group along the Kankai River section is lithologically divided into the Lower, Middle and Upper Siwaliks, in ascending order based on increasing grain size and lithology. The Lower Siwaliks is subdivided into the lower and upper members, whereas the Middle Siwaliks is subdivided into the lower, middle and upper members on the basis of the relative thickness of the sandstone and mudstone beds, frequency of occurrence of these beds, and grain size of sandstone. The Upper Siwaliks is subdivided into the lower and upper members based on the clast size in conglomerate and constituent of the Siwalik sandstone boulders in conglomerate. Based on the lithology, assemblages of sedimentary structure and sediment body architectures, seven facies associations (FA1 to FA7) are recognised. These facies associations are closely related to each lithostratigraphic units of the area. The sediments of the lower and upper members of the Lower Siwaliks are products of the fine-grained meandering and flood flow-dominated meandering systems, respectively. The lower, middle and upper members of the Middle Siwaliks are interpreted as the deposits by sandy meandering, deep sandy braided and shallow braided systems, respectively whereas the lower and upper members of the Upper Siwaliks are the products of gravelly braided to debris flow-dominated braided systems, respectively.   doi: 10.3126/bdg.v12i0.2251 Bulletin of the Department of Geology, Vol. 12, 2009, pp. 63-74

scholarly journals Facies analysis of Sunakothi Formation, Kathmandu basin, Nepal and its significance

2014 ◽  
Vol 47 (1) ◽  
pp. 57-64
Author(s):  
Mukunda Raj Paudel
Keyword(s):  
Lake Level ◽  
Facies Analysis ◽  
Flood Plain ◽  
Delta Front ◽  
Gravel Beds ◽  
Delta Plain ◽  
Facies Associations ◽  
Ripple Sand ◽  
Lacustrine Delta ◽  
Lacustrine Facies

This study decipher facies characteristic of Sunakothi Formation at southern part of Kathmandu Basin. Thick sandy and muddy sequence is found on an open lacustrine facies of the Kalimati Formation. Five facies associations have been recognized within the sandy and muddy facies. These are: (a) muddy rhythmites and silt and laminated to ripple sand bed of the prodeltaic origin (pd), (b) association of cross-stratification, rippledrift and parallel lamination in the lacustrine delta front origin (df), (c) muddy flood-plain and alteration of the fine and coarse sediments of delta-plain origin (dp), (d) sandy to silty rhythmites of the marginal shallow lacustrine origin above the delta-plain (ml), and (e) association of fluvial origin (fl ). Former three associations are interbeded by the thick gravel deposits, which is gravelly braided river origin. Transition from lacustrine to alluvial system is characterized by fluvial and deltaic system in the south. Sedimentology of the Sunakothi Formation indicates deposition during rapid lake level rise and also the thick channelized fluvial gravel beds within the sandy and muddy sequence indicate lake level fall. The cause could be climatic as well as activity of the basin margin tectonics. Sunakothi Formation is the southern counterpart of the Thimi-Gokarna Formations distributed in the northern part of the basin.

APPROACHES TO PALAEOGEOGRAPHIC RECONSTRUCTIONS OF THE LATROBE GROUP, GIPPSLAND BASIN, SOUTHEASTERN AUSTRALIA

2005 ◽  
Vol 45 (1) ◽  
pp. 581 ◽  
Author(s):  
T. Bernecker ◽  
A.D. Partridge
Keyword(s):  
Co2 Storage ◽  
Depositional Environments ◽  
Petroleum Systems ◽  
Fine Grained ◽  
Southeastern Australia ◽  
Depositional System ◽  
Facies Associations ◽  
Marine Fossils ◽  
Coal Accumulation ◽  
Gippsland Basin

In the Gippsland Basin, the seaward extent of paralic coal occurrences can be mapped in successive time slices through the Paleocene and Eocene to provide a series of straight to gently arcuate surrogate palaeoshorelines within the petroliferous Latrobe Group. Palaeogeographic reconstructions that incorporate this information provide a unique perspective on the changes affecting a siliciclastic depositional system on a passive continental margin where basin development has been primarily controlled by thermal sag. In contrast, the absence of calcareous marine fossils and lack of extensive, widespread and thick fine-grained sediments on the marine shelf and continental slope, beyond the seaward limits of coal accumulation, have contributed to the false impression that the Latrobe Group accumulated in a largely non-marine basin. Based on the proposed model for palaeoshoreline delineation, seismic data, sequence analysis, petrography and palynology can be integrated to subdivide the main depositional environments into distinct facies associations that can be used to predict the distribution of petroleum systems elements in the basin. The application of such palaeogeographic models to the older section of the Latrobe Group can improve the identification of these petroleum systems elements in as yet unexplored parts of the Gippsland Basin. Given the recent attention paid to the basin as a CO2 storage province, palaeogeographic interpretations may be able to assist with the selection of appropriate injection sites.

scholarly journals Lithofacies and depositional environment of the Siwalik Group in Samari-Sukaura River area, Central Nepal

2013 ◽  
Vol 16 ◽  
pp. 53-64 ◽  
Author(s):  
Dev Kumar Syangbo ◽  
Naresh Kazi Tamrakar
Keyword(s):  
Depositional Environment ◽  
Foreland Basin ◽  
River System ◽  
Nepal Himalaya ◽  
Meandering River ◽  
Fine Grained ◽  
Architectural Elements ◽  
Central Nepal ◽  
Eastern Zone ◽  
Siwalik Group

Thick sedimentary sequence deposited in the foreland basin of the Nepal Himalaya is represented by the Siwalik Group. The Siwalik Group is well exposed in the Samari-Sukaura River area. The present study is focused in southern portion of the MBT around the Samari-Sukaura area for its depositional environment. The Middle Siwaliks of the Sukaura Road sections is overlained by the Lower Siwaliks which is separated by the Karki Khola Thrust. Extension of the Lower Siwaliks in the Jyamire Khola and the Bundal Khola becomes wider in the eastern Zone. Repetition of the Lower Siwaliks along the southern margin of the MBT is recognized. Depending on lithofacies assemblage and facies analysis, the two broad facies assemblages FA1 and FA2 have been distinguished. FA1 shows SB, FF, LA, LS and CH architectural elements and is interpreted as a product of the fine-grained meandering river system. FA2 shows SB, FF, LA, DA and CH architectural elements and is interpreted as a product of sandy mixed-load meandering river system. DOI: http://dx.doi.org/10.3126/bdg.v16i0.8884   Bulletin of the Department of Geology Vol. 16, 2013, pp. 53-64

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