Controls on fluvial systems in the Siwalik Neogene and Wyoming Paleogene

The 3-km thick Neogene Siwalik Group (Himalayan foredeep in northern Pakistan) and the 2-km thick Paleogene Fort Union/Willwood Formations (Bighorn Basin, Wyoming) both preserve long records of fluvial deposition adjacent to rising mountain belts. Depositional environments and associated habitats change with spatially varying physiography and deposition by river systems that may differ greatly in size, sediment loads, depositional rates, drainage of adjacent floodplains, and taphonomy of organic remains. At times, some environments may not be preserved; for example, avulsion of channels to low areas removes more deposits of channel-distal environments as avulsions increase relative to net sediment aggradation rates. Recognition of such large-scale biases is important because they represent time scales over which long term paleoecological change is reconstructed, and requires knowledge of how drainage systems changed in time and space within these evolving basins.The Siwalik Group was deposited by large rivers that filled a basin extending at least 1000 km along its axis and 150–250 km away from the mountain front. Despite the scale of these rivers relative to Siwalik exposures, transitions between different fluvial systems have been recognized. For example, a 1-km thick sequence bridging the boundary between Chinji and Nagri formations records displacement of a smaller river system (width < 2 km; depth 5-10 m; discharge 1000-1500 m3/s) by a larger system (width <5 km; depth 15-30 m; discharge at least 5,000-10,000 m3/s), with an associated upsection increase (30 to 70%) in the proportion of channel sandstones, increased mean sediment accumulation rates (150 to 300 m/my), decrease in poorly drained floodplain deposits and well developed paleosols, marked decrease in abundance of faunal remains, and a major change in faunal composition. Stratigraphically higher (Dhok Pathan Fm.), there is a lateral transition between deposits of dissimilar, coeval river systems with corresponding differences in local paleoenvironments and vertebrate taphonomy. Although upsection changes in environments and vertebrate faunas may generally reflect extrabasinal controls such as tectonism and climate change, our studies emphasize the importance of recognizing deposits from different contemporaneous river systems before inferring such large-scale controls on paleoenvironmental change through time.The Bighorn Basin is an intermountain foreland basin extending 200 km along its axis and about 80 km across. A large portion of this basin is exposed, and thus it is possible to reconstruct the distribution of river systems and the spatial paleoenvironments in more detail than in the Siwaliks. The Bighorn Basin was traversed along its axis by an early Eocene, north-south flowing river that was joined by smaller rivers flowing transverse to the axis. The proportion of channel sandstones decreases upsection (50 to 25%) from the Fort Union to the Willwood Fm. The proportion of channel sandstones and the abundance of well developed paleosols decrease with increasing net sediment aggradation rates. Although channel deposits are concentrated along the basin axis in a more complex way in some stratigraphic intervals, it is unclear to what extent these changes reflect deposition by different rivers versus extrinsically controlled changes within individual river systems.

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Exploring Environments through Water: An Ethno-Hydrography of the Tibesti Mountains (Central Sahara)

Ethnobiology Letters ◽

10.14237/ebl.12.1.2021.1709 ◽

2021 ◽

Vol 12 (1) ◽

pp. 1-11

Author(s):

Tilman Musch

Keyword(s):

Case Studies ◽

Dynamic Process ◽

Large Scale ◽

River System ◽

Dynamic Processes ◽

Drainage Basins ◽

River Systems ◽

Sandstone Rock ◽

Central Sahara

An ethno-hydrography, studying the organization of space through water, can provide a key to understanding how people conceive their environments in a holistic way. Based on mapping as a dynamic process, different representations of river systems among the Tubu Teda, who live in the Tibesti mountains (Central Sahara), are described in this paper. I first discuss a large-scale subdivision of the mountains into drainage basins, and then representations of a sub-regional and local river system, including an engraving on a sandstone rock. Finally, I discuss these case studies in the context of holistic experiences of environments and the dynamic processes of mapping.

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Synchronizing early Eocene deep-sea and continental records – cyclostratigraphic age models for the Bighorn Basin Coring Project drill cores

Climate of the Past ◽

10.5194/cp-14-303-2018 ◽

2018 ◽

Vol 14 (3) ◽

pp. 303-319 ◽

Cited By ~ 15

Author(s):

Thomas Westerhold ◽

Ursula Röhl ◽

Roy H. Wilkens ◽

Philip D. Gingerich ◽

William C. Clyde ◽

...

Keyword(s):

Deep Sea ◽

Large Scale ◽

Major Change ◽

Terrestrial Ecosystems ◽

Geochemical Data ◽

Bighorn Basin ◽

Early Eocene ◽

Thermal Maximum ◽

The Impact ◽

Drill Cores

Abstract. A consistent chronostratigraphic framework is required to understand the effect of major paleoclimate perturbations on both marine and terrestrial ecosystems. Transient global warming events in the early Eocene, at 56–54 Ma, show the impact of large-scale carbon input into the ocean–atmosphere system. Here we provide the first timescale synchronization of continental and marine deposits spanning the Paleocene–Eocene Thermal Maximum (PETM) and the interval just prior to the Eocene Thermal Maximum 2 (ETM-2). Cyclic variations in geochemical data come from continental drill cores of the Bighorn Basin Coring Project (BBCP, Wyoming, USA) and from marine deep-sea drilling deposits retrieved by the Ocean Drilling Program (ODP). Both are dominated by eccentricity-modulated precession cycles used to construct a common cyclostratigraphic framework. Integration of age models results in a revised astrochronology for the PETM in deep-sea records that is now generally consistent with independent 3He age models. The duration of the PETM is estimated at ∼ 200 kyr for the carbon isotope excursion and ∼ 120 kyr for the associated pelagic clay layer. A common terrestrial and marine age model shows a concurrent major change in marine and terrestrial biota ∼ 200 kyr before ETM-2. In the Bighorn Basin, the change is referred to as Biohorizon B and represents a period of significant mammalian turnover and immigration, separating the upper Haplomylus–Ectocion Range Zone from the Bunophorus Interval Zone and approximating the Wa-4–Wa-5 land mammal zone boundary. In sediments from ODP Site 1262 (Walvis Ridge), major changes in the biota at this time are documented by the radiation of a “second generation” of apical spine-bearing sphenolith species (e.g., S. radians and S. editus), the emergence of T. orthostylus, and the marked decline of D. multiradiatus.

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Synchronizing early Eocene deep-sea and continental records – new cyclostratigraphic age models from the Bighorn Basin Coring Project

10.5194/cp-2017-74 ◽

2017 ◽

Cited By ~ 1

Author(s):

Thomas Westerhold ◽

Ursula Röhl ◽

Roy Wilkens ◽

Philip D. Gingerich ◽

Will Clyde ◽

...

Keyword(s):

Deep Sea ◽

Large Scale ◽

Major Change ◽

Terrestrial Ecosystems ◽

Geochemical Data ◽

Bighorn Basin ◽

Early Eocene ◽

Ocean Drilling Program ◽

Thermal Maximum ◽

The Impact

Abstract. A consistent stratigraphic framework is required to understand the effect of major climate perturbations of the geological past on both marine and terrestrial ecosystems. Transient global warming events in the early Eocene, 56–54 Ma ago, show the impact of large scale input of carbon into the ocean-atmosphere system. Here we provide the first time-scale synchronization of continental and marine deposits spanning the Paleocene-Eocene Thermal Maximum (PETM) and the interval just prior to the Eocene Thermal Maximum 2 (ETM-2). Cyclic variations in geochemical data come from continental drill cores of the Bighorn Basin Drilling Project (BBCP, Wyoming, USA) and from marine deep-sea drilling deposits retrieved by the Ocean Drilling Program (ODP). Both are dominated by eccentricity modulated precession cycles that are used to construct a common cyclostratigraphic framework. Integration of age models results in a revised astrochronology for the PETM in deep-sea records that is now generally consistent with independent 3He age models. The duration of the PETM is estimated at ~ 200 kyr for the CIE and ~ 120 kyr for the pelagic clay layer. A common terrestrial and marine age model shows a concurrent major change in marine and terrestrial biotas ~ 200 kyr before ETM-2. In the Bighorn Basin, the change is referred to as Biohorizon B, and it represents a period of significant mammalian turnover and immigration, separating the upper Haplomylus-Ectocion Range Zone from the Bunophorus Interval Zone and approximating the Wa-4–Wa-5 land mammal zone boundary. In sediments from ODP Site 1262 (Walvis Ridge), major changes in the biota at this time are documented by the radiation of a 2nd generation of apical spine-bearing sphenoliths species (e.g., S. radians and S. editus), the emergence of T. orthostylus, and the marked decline of D. multiradiatus.

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Hydrology influences breeding time in the white-throated dipper

BMC Ecology ◽

10.1186/s12898-020-00338-y ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Anna L. K. Nilsson ◽

Thomas Skaugen ◽

Trond Reitan ◽

Jan Henning L’Abée-Lund ◽

Marlène Gamelon ◽

...

Keyword(s):

Climate Change ◽

River Discharge ◽

Large Scale ◽

Time Window ◽

River System ◽

Open Water ◽

Local Conditions ◽

Environmental Indices ◽

Groundwater Levels ◽

Breeding Time

Abstract Background Earlier breeding is one of the strongest responses to global change in birds and is a key factor determining reproductive success. In most studies of climate effects, the focus has been on large-scale environmental indices or temperature averaged over large geographical areas, neglecting that animals are affected by the local conditions in their home ranges. In riverine ecosystems, climate change is altering the flow regime, in addition to changes resulting from the increasing demand for renewable and clean hydropower. Together with increasing temperatures, this can lead to shifts in the time window available for successful breeding of birds associated with the riverine habitat. Here, we investigated specifically how the environmental conditions at the territory level influence timing of breeding in a passerine bird with an aquatic lifestyle, the white-throated dipper Cinclus cinclus. We relate daily river discharge and other important hydrological parameters, to a long-term dataset of breeding phenology (1978–2015) in a natural river system. Results Dippers bred earlier when winter river discharge and groundwater levels in the weeks prior to breeding were high, and when there was little snow in the catchment area. Breeding was also earlier at lower altitudes, although the effect dramatically declined over the period. This suggests that territories at higher altitudes had more open water in winter later in the study period, which permitted early breeding also here. Unexpectedly, the largest effect inducing earlier breeding time was territory river discharge during the winter months and not immediately prior to breeding. The territory river discharge also increased during the study period. Conclusions The observed earlier breeding can thus be interpreted as a response to climate change. Measuring environmental variation at the scale of the territory thus provides detailed information about the interactions between organisms and the abiotic environment.

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Depositional environments and paleogeography in the Albian Moosebar Formation and adjacent fluvial Gladstone and Beaver Mines formations, Alberta

Canadian Journal of Earth Sciences ◽

10.1139/e84-076 ◽

1984 ◽

Vol 21 (6) ◽

pp. 698-714 ◽

Cited By ~ 8

Author(s):

David R. Taylor ◽

Roger G. Walker

Keyword(s):

Brackish Water ◽

Late Jurassic ◽

Major Change ◽

Depositional Environments ◽

Fluvial Deposits ◽

Maximum Thickness ◽

The North ◽

Major Exception ◽

Flow Directions ◽

Sand Bodies

The marine Moosebar Formation (Albian) has a currently accepted southerly limit at Fall Creek (Ram River area). It consists of marine mudstones with some hummocky and swaley cross-stratified sandstones indicating a storm-dominated Moosebar (Clearwater) sea. We have traced a tongue of the Moosebar southward to the Elbow River area (150 km southeast of Fall Creek), where there is a brackish-water ostracod fauna. Paleoflow directions are essentially northwestward (vector mean 318°), roughly agreeing with turbidite sole marks (329°) in the Moosebar of northeastern British Columbia.The Moosebar sea transgressed southward over fluvial deposits of the Gladstone Formation. In the Gladstone, thick channel sands (4–8 m) are commonly multistorey (up to about 15 m), with well developed lateral accretion surfaces. The strike of the lateral accretion surfaces and the orientation of the walls of channels and scours indicate northwestward flow (various vector means in the range 307–339°). The Moosebar transgression was terminated by construction of the Beaver Mines floodplain, with thick, multistorey sand bodies up to about 35 m thick. Flow directions are variable, but various vector means roughly cluster in the north to northeast segment. This indicates a major change in dispersal direction from the Gladstone and Moosebar formations.A review of many Late Jurassic and Cretaceous units shows a dominant dispersal of sand parallel to regional strike. This flow is mostly north-northwestward (Passage beds, Cadomin, Gladstone, Moosebar, Gates, Chungo), with the southeasterly dispersal of the Cardium being the major exception. Only at times of maximum thickness of clastic input (Belly River and higher units, and possibly Kootenay but there are no published paleocurrent data) does the sediment disperse directly eastward or northeastward from the Cordillera toward the Plains.

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Chutes and ladders and other games we play with rivers. II. Simulated effects of translocation on white sturgeon

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f05-225 ◽

2006 ◽

Vol 63 (1) ◽

pp. 176-185 ◽

Cited By ~ 9

Author(s):

Henriette I Jager

Keyword(s):

Fish Species ◽

Simulation Study ◽

River System ◽

Genetic Effects ◽

White Sturgeon ◽

Acipenser Transmontanus ◽

River Systems ◽

Short Segment ◽

River Fragmentation ◽

Demographic Effects

Restoring connectivity is viewed as an important recovery option for fish species adversely affected by river fragmentation. This simulation study quantified the genetic and demographic effects of translocation on metapopulations of white sturgeon (Acipenser transmontanus) inhabiting a series of long (source) and short (sink) river segments. Genetic effects were predictable; upstream translocations increased introgression and downstream translocations had no effect. Demographic results suggest that indiscriminant efforts to reconnect populations may do more harm than good. Simulated river systems with high interspersion of long and short segments and a long segment far upstream tended to benefit most from translocation, but only when narrow screening or downstream passage was also provided below the river segment receiving fish. When combined with narrow screening, upstream translocation to a long segment subsidizing several downstream short segments produced the best results. Downstream passage outperformed narrow screening only when the translocation recipient was a short segment in a river system with low interspersion and no long, upstream river segment. This model-based evaluation of reconnection options has helped to refine ideas about restoring populations in fragmented rivers by predicting which options benefit riverine metapopulations as a whole.

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Environment of Deposition and Paleogeography of the Late Cretaceous Glenburn Formation, Eastern North Island, New Zealand

10.26686/wgtn.17071979 ◽

2021 ◽

Author(s):

◽

James McClintock

Keyword(s):

New Zealand ◽

Late Cretaceous ◽

Large Scale ◽

East Coast ◽

Three Dimensional ◽

Depositional Environments ◽

Tectonic Deformation ◽

Turbidity Currents ◽

Submarine Fan ◽

Submarine Channels

<p>The Glenburn Formation of the East Coast of New Zealand is a Late Cretaceous sedimentary formation consisting of alternating layers of sandstone, mudstone and conglomerate. The Glenburn Formation spans a depositional timeframe of over 10 Ma, is over 1000 m thick, is regionally extensive and is possibly present over large areas offshore. For these reasons, it is important to constrain the paleoenvironment of this unit. Late Cretaceous paleogeographic reconstructions of the East Coast Basin are, however, hampered by a number of factors, including the pervasive Neogene to modern tectonic deformation of the region, the poorly understood nature of the plate tectonic regime during the Cretaceous, and a lack of detailed sedimentological studies of most of the region’s Cretaceous units. Through detailed mapping of the Glenburn Formation, this study aims to improve inferences of regional Cretaceous depositional environments and paleogeography. Detailed facies based analysis was undertaken on several measured sections in eastern Wairarapa and southern Hawke’s Bay. Information such as bed thickness, grain size and sedimentary structures were recorded in order to identify distinct facies. Although outcrop is locally extensive, separate outcrop localities generally lie in different thrust blocks, which complicates comparisons of individual field areas and prevents construction of the large-scale, three-dimensional geometry of the Glenburn Formation. Glenburn Formation consists of facies deposited by sediment gravity flows that were primarily turbidity currents and debris flows. Facies observed are consistent with deposition on a prograding submarine fan system. There is significant variation in facies both within and between sections. Several distinct submarine fan architectural components are recognised, such as fan fringes, fan lobes, submarine channels and overbank deposits. Provenance and paleocurrent indicators are consistent with deposition having occurred on several separate submarine fans, and an integrated regional paleogeographic reconstruction suggests that deposition most likely occurred in a fossil trench following the mid-Cretaceous cessation of subduction along the Pacific-facing margin of Gondwana.</p>

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Automated Detection of Instability-Inducing Channel Geometry Transitions in Saint-Venant Simulation of Large-Scale River Networks

Water ◽

10.3390/w13162236 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2236

Author(s):

Cheng-Wei Yu ◽

Ben R. Hodges ◽

Frank Liu

Keyword(s):

Large Scale ◽

Open Channel ◽

Search Algorithm ◽

Shallow Water Equation ◽

Stable Solution ◽

River Networks ◽

River Systems ◽

Channel Network ◽

Channel Geometry ◽

Venant Equation

A new sweep-search algorithm (SSA) is developed and tested to identify the channel geometry transitions responsible for numerical convergence failure in a Saint-Venant equation (SVE) simulation of a large-scale open-channel network. Numerical instabilities are known to occur at “sharp” transitions in discrete geometry, but the identification of problem locations has been a matter of modeler’s art and a roadblock to implementing large-scale SVE simulations. The new method implements techniques from graph theory applied to a steady-state 1D shallow-water equation solver to recursively examine the numerical stability of each flowpath through the channel network. The SSA is validated with a short river reach and tested by the simulation of ten complete river systems of the Texas–Gulf Coast region by using the extreme hydrological conditions recorded during hurricane Harvey. The SSA successfully identified the problematic channel sections in all tested river systems. Subsequent modification of the problem sections allowed stable solution by an unsteady SVE numerical solver. The new SSA approach permits automated and consistent identification of problem channel geometry in large open-channel network data sets, which is necessary to effectively apply the fully dynamic Saint-Venant equations to large-scale river networks or for city-wide stormwater networks.

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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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ĐẶC ĐIỂM HỆ THỐNG SÔNG CỔ VÀ TÁC ĐỘNG NHÂN SINH DỰA TRÊN KẾT QUẢ MÔ HÌNH TIẾN HÓA TỈ LỆ LỚN KHU VỰC CHÂU THỔ SÔNG HỒNG

Tạp chí Khoa học và Công nghệ Biển ◽

10.15625/1859-3097/19/4/12706 ◽

2020 ◽

Vol 19 (4) ◽

pp. 463-478

Author(s):

Mai Duc Dong ◽

Phung Van Phach ◽

Nguyen Trung Thanh ◽

Duong Quoc Hung ◽

Pham Quoc Hiep ◽

...

Keyword(s):

Late Pleistocene ◽

River System ◽

River Network ◽

River Delta ◽

Red River ◽

River Systems ◽

Red River Delta ◽

The World ◽

History Of

The Simclast model has been verified and applied effectively in simulating the delta development for some major deltas in the world. In this study, we applied the model Simclast for simulating the history of the Red river delta development in late Pleistocene-Holocene. Results of the model reveal that the mainland of study area had reduced rapidly during transgression period (10,000-8,000 BP). The morphology changed significantly in the paleo-Red and Day river systems, but slightly in the paleo Thai Binh river system. The paleo-river network had been active in upper part before 11,000 BP and then shifted seaward until 2,000 BP. The river-sea interaction causes erosion and accumulation; as a result the morphology changed remarkably. The paleo-Thai Binh river had been inactive until 5,500 BP and then it was active but the morphology had not varied remarkably. The recent coastline generated from Simclast is relatively in accordance with the present coastline.

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