Chronology and significance of a Holocene sedimentary profile from Clear Creek, Lake Erie shoreline, Ontario

1985 ◽  
Vol 22 (8) ◽  
pp. 1133-1138 ◽  
Author(s):  
P. J. Barnett ◽  
J. P. Coakley ◽  
J. Terasmae ◽  
C. E. Winn
Keyword(s):  
Lake Erie ◽  
Water Levels ◽  
Oxbow Lake ◽  
Main Stream ◽  
Present Level ◽  
Pollen Diagram ◽  
Postglacial History ◽  
Abandoned Channel ◽  
Stream System ◽  
History Of

An abandoned channel of Clear Creek, cut approximately 5 m below the present level of Lake Erie, was cored and the infilling sediments were examined. The postglacial history of this channel was reconstructed based on sedimentological, palynological, and chronological studies.The channel was cut initially some 15 m into Wentworth Till during the low-water Early Lake Erie stage. The infilling or aggradation of the channel began about 9500–9000 years BP, probably in response to rising water levels in the Lake Erie basin.This channel was cut off from the main channel shortly afterwards and an oxbow lake formed. By 7000 years BP, complete cutoff of the channel from the main stream system had occurred, allowing peat to accumulate. Eventually trees grew on this site, 4000 years BP.The diversion of glacial Lake Nipissing drainage into the Lake Erie basin may be reflected in the greater abundance of silt laminations in the peat of the upper part of the channel fill between 5975 ± 150 (BGS-899) and 3900 ± 100 (BGS-898) years BP.A rise in water level in the Lake Erie basin possibly over the Clear Creek site is recorded by the "drowning" of the forest shortly after 3900 ± 100 (BGS-898) years BP and the truncation of the Clear Creek site pollen diagram.

History of sedimentation in the northwestern Lake Superior basin and its relation to Lake Agassiz overflow

1988 ◽  
Vol 25 (10) ◽  
pp. 1660-1673 ◽  
Author(s):  
James T. Teller ◽  
Paul Mahnic
Keyword(s):  
Lake Superior ◽  
Proximal Part ◽  
Water Levels ◽  
Lake Agassiz ◽  
Nearshore Processes ◽  
Postglacial History ◽  
Thunder Bay ◽  
Clayey Silt ◽  
History Of ◽  
Glacial Advance

Following the Marquette glacial advance, which blocked the eastern outlets of Lake Agassiz and reached northern Michigan about 10 000 years BP, the ice margin wasted back toward the northeast, eventually allowing Lake Agassiz to overflow into the Lake Superior basin through a series of channels. Sediments deposited east of Thunder Bay near the mouth of the Wolf, Wolfpup, Shillabeer, and Black Sturgeon channels reflect three phases in the history of Lake Superior and provide the basis for reconstructing the early postglacial history of the region.The lower part of the sedimentary sequence in the northwestern Superior Basin consists of a distinctive red, stoney, sandy till deposited during the Marquette glacial advance and is overlain by pink rhythmites deposited in Lake Superior when it was a deep proglacial lake at the Minong level. The nearly 300 rhythmites deposited at this time typically consist of 4 cm thick silt + clay couplets, which are punctuated by silt laminae and sandy turbidites that probably represent major thaw periods or storms. These are seasonal rhythmites, deposited prior to the reopening of the Lake Agassiz outlets into the Superior Basin, and they display a decrease in dropstones, grain size, and thickness upsection that reflects a receding ice margin.The first eastern outlets of Lake Agassiz were uncovered around 9500 years BP, and water began overflowing into the Superior Basin in a series of catastrophic floods. Subaqueous fans developed at the Wolf, Wolfpup, and Shillabeer confluence and at the mouth of the Black Sturgeon channel. Large sandy turbidites, 45–65 cm thick, were deposited in the proximal part of these fans, with scouring and large (1 m) trough cross-beds resulting from the largest Lake Agassiz floods. These sediments are transitional to distal, clayey silt rhythmites, 10–22 cm thick. A gradual decrease in flooding from Lake Agassiz is reflected in the upward decrease in rhythmite thickness to 1–3 cm by about 8200 years BP. The final sequence of sediments shows a transition to sandy units as water levels dropped in the Superior Basin and the influence of nearshore processes increased.

Performance of Light Coastal Structures Under Normal and High Water Conditions

1975 ◽  
Vol 2 (4) ◽  
pp. 381-391 ◽  
Author(s):  
J. W. Kamphuis
Keyword(s):  
Lake Erie ◽  
High Water ◽  
Water Levels ◽  
Coastal Protection ◽  
Coastal Structures ◽  
Water Conditions ◽  
Protection Structures

A number of lightweight coastal protection structures, built on the Lake Erie shore are discussed in this paper. There were two constraints on the design; limited funds and a very precarious downdrift beach. Thus the structures were inexpensive and the protection was low-key to prevent damage downdrift. In 1972–1974 these structures were subjected to a combination of large waves and high water levels and thus they were tested well beyond their design limits.The paper discusses the structures, their performance under normal conditions, and their performance during and after the abnormally high water levels. It is found that inexpensive, low-key structures are sufficiently strong to survive normal conditions, but fail by overtopping and flanking under conditions beyond their low design limits.

scholarly journals An automatic lake-model application using near real-time data forcing: Development of an operational forecast model for Lake Erie

2021 ◽  
Author(s):  
Shuqi Lin ◽  
Leon Boegman ◽  
Shiliang Shan ◽  
Ryan Mulligan
Keyword(s):  
Open Access ◽  
Real Time ◽  
Public Safety ◽  
Lake Erie ◽  
Water Resource Management ◽  
Computational Models ◽  
Fishery Management ◽  
Water Levels ◽  
Time Data ◽  
Forecast System

Abstract. For enhanced public safety and water resource management, a three-dimensional operational lake hydrodynamic forecast system called COASTLINES (Canadian cOASTal and Lake forecastINg modEl System) was developed. The modelling system is built upon the Aquatic Ecosystem Model (AEM3D) model, with predictive simulation capabilities developed and tested for a large lake (i.e., Lake Erie). The open-access web-based platform derives model forcing, code execution, post-processing and visualization of the model outputs, including water level elevations and temperature, is in near real-time. COASTLINES currently generates 240-h predictions using atmospheric forcing from 15 km and 25 km horizontal-resolution operational meteorological products from the Environment Canada Global Deterministic Forecast System (GDPS). Simulated water levels were validated against observations from 6 gauge stations, with model error increasing for longer forecast times. Satellite images and lake buoys were applied to validate forecast lake surface temperature (LST) and the water column thermal stratification. The forecast LST is as accurate as hindcasts, with a root-mean-square-deviation < 2 ℃. COASTLINES predicts storm-surge events and up-/down-welling events that are important for flood water and drinking water/fishery management, respectively. Model forecasts are available in real-time at https://coastlines.engineering.queensu.ca/. This study provides an example of the successful development of an operational forecasting system, entirely driven by open-access data, that may be easily adapted to simulate aquatic systems or to drive other computational models, as required for management and public safety.

Palynology and Paleoecology of Postglacial Sediments from the Lower Fraser River Canyon of British Columbia

1975 ◽  
Vol 12 (5) ◽  
pp. 745-756 ◽  
Author(s):  
R. W. Mathewes ◽  
G. E. Rouse
Keyword(s):  
Tsuga Heterophylla ◽  
Climatic Conditions ◽  
Douglas Fir ◽  
Fraser River ◽  
Pollen Assemblage ◽  
Glacial Ice ◽  
Transitional Area ◽  
Postglacial History ◽  
History Of Vegetation ◽  
History Of

The postglacial history of vegetation in the Yale area of the lower Fraser River Canyon is described from sediments of two lakes using percentage pollen analysis supplemented with macrofossil evidence and radiocarbon dating. Deposition of postglacial sediments, ranging from basal clays to gyttjas, began about 11 500 y B.P. Three distinct pollen assemblage zones are distinguished, reflecting in part the main climatic conditions for the intervals. The oldest zone, with high percentages of pine (Pinus) and alder (Alnus) pollen, suggests cool and moist conditions following withdrawal of glacial ice. This is followed by marked increases in Douglas-fir (Pseudotsuga), grasses and other nonarboreal pollen, suggesting in part, warmer and drier conditions. The third zone, ranging from about the Mt. Mazama ash at 6600 y B.P. to the present, is marked by high alder and Douglas-fir, and increasing cedar (Thuja-Chamaecyparis type), western hemlock (Tsuga heterophylla), fir (Abies) and birch; an assemblage indicating a return to wetter conditions. This sequence contrasts with previously described successions that recognized the classical Hypsithermal in adjacent areas. The sequence of inferred vegetational changes, although similar to those described for the Haney area to the west, suggests that the Yale area has been a biogeoclimatically transitional area for much of postglacial time.

scholarly journals Anatomy of simultaneous flood peaks at a lowland confluence

2018 ◽  
Vol 22 (10) ◽  
pp. 5599-5613 ◽  
Author(s):  
Tjitske J. Geertsema ◽  
Adriaan J. Teuling ◽  
Remko Uijlenhoet ◽  
Paul J. J. F. Torfs ◽  
Antonius J. F. Hoitink
Keyword(s):  
Economic Value ◽  
Water Levels ◽  
Simultaneous Occurrence ◽  
Main Stream ◽  
Time Lags ◽  
Main River ◽  
Long Duration ◽  
Independent Observations ◽  
Flood Peaks ◽  
The Impact

Abstract. Lowlands are vulnerable to flooding due to their mild topography in often densely populated areas with high social and economic value. Moreover, multiple physical processes coincide in lowland areas, such as those involved in river–sea interactions and in merging rivers at confluences. Simultaneous occurrence of such processes can result in amplifying or attenuating effects on water levels. Our aim is to understand the mechanisms behind simultaneous occurrence of discharge waves in a river and its lowland tributaries. Here, we introduce a new way of analyzing lowland discharge and water level dynamics, by tracing individual flood waves based on dynamic time warping. We take the confluence of the Meuse River (∼33 000 km2) with the joining tributaries of the Dommel and Aa rivers as an example, especially because the January 1995 flood at this confluence was the result of the simultaneous occurrence of discharge peaks in the main stream and the tributaries and because independent observations of water levels and discharge are available for a longer period. The analysis shows that the exact timing of the arrival of discharge peaks is of little relevance because of the long duration of the average discharge wave compared to typical time lags between peaks. The discharge waves last on average 9 days, whereas the lag time between discharge peaks in the main river and the tributaries is typically 3 days. This results in backwaters that can rise up to 1.5 m over a distance of 4 km from the confluence. Thus, local measures to reduce the impact of flooding around the confluence should account for the long duration of flood peaks in the main system.

Modelling the Pathways of Toxic Contaminants in the St. Clair-Detroit River System Using the Toxfate Model: The Fate of Perchloroethylene

1986 ◽  
Vol 21 (3) ◽  
pp. 411-421 ◽  
Author(s):  
Efraim Halfon
Keyword(s):  
Half Life ◽  
Lake Erie ◽  
River System ◽  
High Water ◽  
Water Levels ◽  
Water Soluble ◽  
Detroit River ◽  
Wind Speeds ◽  
High Volatility ◽  
Local Water

Abstract Perchloroethylene (PERC) is a heavier-than-water, soluble and volatile solvent used primarily in the dry cleaning business. Black puddles (popularly known the the “blob”), containing several contaminants inducing PERC, were reported in the St. Clair River bottom sediments downstream from Sarnia in 1984 and in 1985. The TOXFATE model is used to predict the fate of PERC and the relative importance of volatilization in relation to water transport. Simulations show that in the St. Clair-Detroit River system about 82% (78-87%). under a variety of temperature and wind conditions) of the PERC loading is volatilized, about 17% (12-21%) of loading enters Lake Erie (more in winter, less in summer) and only about 1% remains in the system. The residence half life of PERC being transported in the water from Sarnia to Lake Erie is 350-400 hours and the half life of PERC being volatilized is 80-85 hours. A sensitivity analysis shows the importance of knowing the daily loadings to compute, in real time, local water concentrations following a PERC spill. The high water levels in the St. Clair River system do not influence the fate of PERC. Given the high volatility of PERC low temperatures and wind speeds do not reduce significantly the rate of removal of PERC from the system through volatilize nation.

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