THE SUM IS WORTH MORE THAN THE PARTS: INTEGRATING 3D MODELS TO REFINE THE REGIONAL STRATIGRAPHIC FRAMEWORK FOR HYDROGEOLOGIC STUDIES ABOVE THE NIAGARA ESCARPMENT IN SOUTHERN ONTARIO

2020 ◽  
Author(s):  
Abigail K. Burt ◽  
◽  
Andy F. Bajc
Keyword(s):  
3D Models ◽  
Southern Ontario ◽  
Niagara Escarpment ◽  
Stratigraphic Framework

Trend surface analysis of major late Wisconsinan till sheets, Brantford–Woodstock area, southern Ontario

1978 ◽  
Vol 15 (6) ◽  
pp. 1025-1036 ◽  
Author(s):  
W. R. Cowan
Keyword(s):  
Strong Relationship ◽  
High Energy ◽  
Field Observations ◽  
Trend Surface Analysis ◽  
Southern Ontario ◽  
Niagara Escarpment ◽  
Regional Trends ◽  
Grade Material ◽  
Late Wisconsinan ◽  
Relationship Of

Linear and quadratic trend surfaces were computed for textural, carbonate, clast, and heavy mineral properties of the Catfish Creek (Nissouri Stadial), Port Stanley (Port Bruce Stadial), Tavistock (Port Bruce Stadial), and Wentworth (Port Huron Stadial) tills.Catfish Creek Till pebble grade material provided trend surfaces reflecting the underlying bedrock. However, an overall lack of regional trends in Catfish Creek Till is consistent with field observations that indicate remarkable uniformity for this till over several hundred square kilometres, a phenomenon that is believed to reflect the high energy of this ice sheet. Carbonates in Port Stanley Till were found to increase from east to west as the Silurian–Devonian contact was crossed. Tavistock Till was found to have increasing sand content and decreasing silt content from northwest to southeast owing to incorporation of underlying glaciofluvial sediments; pebble trends reflect the underlying bedrock for the most part. Wentworth Till trend surfaces for carbonates and pebbles show high dolomite near the Niagara Escarpment to the east and northeast with a dilution of dolomite and influx of limestone to the southwest.The strong relationship of the trend surfaces to substrate materials indicates the basal nature of the tills and the local origin of most glacial deposits. Pebble lithologies provide much information about local bedrock and drift prospectors should give close consideration to coarse fragments.

scholarly journals Three-Dimensional Modeling and Fluid Flow Simulation for the Quantitative Description of Permeability Anisotropy in Tidal Flat Carbonate

Energies ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5557
Author(s):  
Hassan A. Eltom ◽  
Nabil A. Saraih ◽  
Oliver G. Esteva ◽  
Lundi Kusuma ◽  
Saleh Ahmed ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Tidal Flat ◽  
Three Dimensional ◽  
Flow Simulation ◽  
3D Models ◽  
Depositional Environments ◽  
High Permeability ◽  
Stratigraphic Framework ◽  
Permeability Anisotropy ◽  
Lithofacies Association

Three-dimensional (3D) facies and petrophysical models were generated from previously published data of carbonate strata in the Dam Formation (eastern Saudi Arabia) to quantitatively investigate, describe, understand, model, and predict the permeability anisotropy in tidal flat carbonate on the basis of a sequence stratigraphic framework. The resulting 3D models were used to conduct fluid flow simulations to demonstrate how permeability anisotropy influences the production of hydrocarbons and ultimately affects decisions concerning future drilling in the exploration and development of carbonate reservoirs with tidal flat strata. The constructed 3D facies model consists of four lithofacies associations, two of which are grain-dominated associations and two of which are mud-dominated associations. These lithofacies associations vary spatially in four reservoir zones (zones 1 to 4), which represent two fourth-order sequences in the uppermost part of the Dam Formation. Zones 1 and 3 consist of transgressive parasequences, and zones 2 and 4 consist of the regressive parasequences of these sequences. The 3D porosity and permeability models have a coherent match with the distribution of the lithofacies and the stratigraphic framework of the Dam Formation. The results suggest that the permeability anisotropy in zones 1 and 3 is controlled by the occurrence of the grain-dominated lithofacies associated with tidal flat channels. This lithofacies association overlies the sequence boundaries of sequences 1 and 3, forms reservoir bodies with relatively high permeability values, and is elongated perpendicular to the shoreline of the depositional environment. In contrast, permeability anisotropy in zones 2 and 4 is thought to be controlled by the occurrence of the grain-dominated lithofacies associated with the oolitic shoal. This lithofacies association overlies the maximum flooding surface of sequences 2 and 4, forms reservoir bodies with relatively high permeability values, and is elongated parallel to the shoreline of the depositional environments. Fluid flow simulation results suggest that the trend in hydrocarbon production from the constructed 3D models depends on permeability anisotropy in each reservoir zone. Thus, recognizing trends in permeability anisotropy, which can be predicted using sequence stratigraphy, could help to identify potential areas for future drilling.

THE STATUS OF PARASITES OF THE APPLE MAGGOT, RHAGOLETIS POMONELLA (DIPTERA: TEPHRITIDAE), IN ONTARIO

1971 ◽  
Vol 103 (4) ◽  
pp. 507-512 ◽  
Author(s):  
L. G. Monteith
Keyword(s):  
Lake Ontario ◽  
Rhagoletis Pomonella ◽  
Southern Ontario ◽  
Niagara Escarpment ◽  
The Status

AbstractOpius melleus Gah. and O. lectus Gah. were the only parasites of Rhagoletis pomonella (Walsh) found in southern Ontario during a 4-year survey. The parasites were found only in the Niagara Region on the slope of the Niagara Escarpment and between it and Lake Ontario. The population of parasites was low though they appeared to be well adapted to attack R. pomonella. They were found in, or adjoining, unsprayed sites where there was shrubby growth under the trees infested by R. pomonella.

The extent of old-growth Thuja occidentalis on cliffs of the Niagara Escarpment

1991 ◽  
Vol 69 (7) ◽  
pp. 1628-1636 ◽  
Author(s):  
D. W. Larson ◽  
P. E. Kelly
Keyword(s):  
Cross Sections ◽  
Forest Ecosystems ◽  
Forest Ecology ◽  
Eastern North America ◽  
Old Growth ◽  
Southern Ontario ◽  
Thuja Occidentalis ◽  
Selective Sampling ◽  
Niagara Escarpment ◽  
Old Growth Forest

Extensive random sampling of populations of Thuja occidentalis growing on vertical cliffs of the Niagara Escarpment in southern Ontario, Canada, was conducted to determine the extent of an old-growth forest that had recently been described. Nine sites distributed along the length of the escarpment were intensively sampled and from these, 1254 increment cores or cross sections were obtained from 872 trees in all age categories. The results show that all cliffs support a broadly similar old-growth forest of stunted trees, but that statistically significant differences were found in the numbers of trees among sites. No large differences among sites were found in heights or diameters of trees. Maximum ages of 532 (sampled) and 814 years (estimated) were found in the random census, although in subsequent selective sampling, intact stems up to 1032 years were found. The incidence of fire and cutting by humans was also measured, but little evidence of such disturbances was found. It is concluded that exposed cliff faces of the Niagara Escarpment support one of the oldest, most extensive, and most intact old-growth forest ecosystems yet described for eastern North America. The opportunities for the study of basic forest ecology and especially for dendrochronology are considerable. Key words: Thuja occidentalis, old growth, Niagara Escarpment, cliff, age structures.

scholarly journals Significance of Sedimentological Studies on the Wisconsinan Stratigraphy of Southern Ontario

2007 ◽  
Vol 39 (3) ◽  
pp. 255-273 ◽  
Author(s):  
David R. Sharpe ◽  
Peter J. Barnett
Keyword(s):  
Lake Basin ◽  
Glacial Ice ◽  
Southern Ontario ◽  
Depositional Processes ◽  
Stratigraphic Framework ◽  
Large Channel ◽  
Late Wisconsinan ◽  
Subglacial Meltwater ◽  
Main Effects

ABSTRACTDetailed facies mapping along Lake Erie and Lake Ontario Bluffs, plus other studies illustrate that sedimentological studies, especially those with geomorphic or landform control, have had three main effects on the Wisconsinan stratigraphy of Ontario: (1) improved understanding of depositional processes and environments of several major rock stratigraphic units, without altering the stratigraphic framework, (2) aided correlation of drift sequences, and (3) questioned previous interpretations and stratigraphic correlations of drift sequences. Thus sedimentological analysis can not be separated from stratigraphy because the interpretation of depositional environnments of many mapped strata relies on their geometry and the inclusion of regional data. The geomorphic control provided by sedimentological study of surface landforms is also important because assessment of older buried sediments such as those at the Scarborough Bluffs has been hampered by the failure to determine landform control. The Late Wisconsinan stratigraphy of Southern Ontario generally remains unchanged, except for questions on the role of climate versus ice margin dynamics. The pre-Late Wisconsinan stratigraphy is scarce and not well defined, yet sedimentary studies support the presence of glacial ice in the Ontario Lake basin for all of the Middle Wisconsinan and possibly earlier, including the formation of the Scarborough delta. Large channel cut and fill sequences in the Toronto area (Pottery Road Formation), initially interpreted as resulting from subaerial erosion, were probably formed by subaqueous or subglacial meltwater erosion. If so, the pre-Late Wisconsinan stratigraphy in southern Ontario changes because the Pottery Road Formation may not be an Early Wisconsinan correlative of the St. Pierre beds. The channel example illustrates that stratigraphie correlation without sedimentological investigations may be misleading.

The influence of fracture networks on stability and geohazards of the Niagara Escarpment in southern Ontario

2021 ◽  
Author(s):  
Serena Formenti ◽  
Alexander Peace ◽  
John Waldron ◽  
Carolyn Eyles ◽  
Rebecca Lee
Keyword(s):  
Fluid Flow ◽  
Structural Stability ◽  
Fracture Network ◽  
Eastern United States ◽  
Fracture Networks ◽  
Network Modelling ◽  
Southern Ontario ◽  
Niagara Escarpment ◽  
Bedding Planes ◽  
Geologic Fractures

<p>The Niagara Escarpment is a geological feature comprised of highly fractured Ordovician and Silurian shales and carbonates stretching through southern Ontario and parts of the north-eastern United States. Differential erosion of the shale and carbonate strata has generated a steep cliff face bisecting the city of Hamilton, Ontario. Fractures occur throughout the cliff face and result in the formation of loose blocks of rock that are subject to erosion through rockfalls. This presents structural stability issues and an associated geohazard, which is of particular concern due to the proximity of the escarpment to city infrastructure. Previous work has alluded towards the role of geologic fractures in controlling erosion and stability of the Niagara Escarpment, but the causal mechanisms and extent to which these processes operate remains unclear. As such, the aim of this study is to quantify and analyse fracture networks using a combined field and numerical modelling-based approach to understand the distribution and nature of fractures throughout the escarpment, their connectivity, fluid flow properties, and relationship to structural stability. The location, orientation, and aperture of fractures were systematically quantified and documented around Hamilton. Data were plotted and analysed using the software Orient to identify clusters representative of fracture sets and to calculate average fracture set orientations and the respective confidence intervals. Three primary sets of geological fractures were identified including: 1) a near-vertical bedding confined set oriented north-south, 2) a near-vertical bedding confined set oriented east-west and 3) sedimentary bedding planes which have facilitated fracture migration and controlled resultant fracture geometry. Discrete fracture network modelling of these fracture sets in MOVE highlights their high degree of connectivity and indicates that the distribution and nature of these discontinuities are predominant controls on the locations and sizes of rock fragments generated on the cliff face resulting in rockfalls. Moreover, fracture-controlled porosity is a significant contributor to fluid flow throughout the escarpment. We conclude that geologic fractures present a first-order control on the stability of the Niagara Escarpment near Hamilton.</p>

On the origin of the Oak Ridges Moraine, southern Ontario

1985 ◽  
Vol 22 (2) ◽  
pp. 300-303 ◽  
Author(s):  
L. J. Chapman
Keyword(s):  
Lake Ontario ◽  
Glacial Lake ◽  
Stream Channel ◽  
Outlet Channel ◽  
Southern Ontario ◽  
Oak Ridges Moraine ◽  
Standing Water ◽  
Niagara Escarpment

Widespread occurrences of stratified silt and clay have been found under the surface sands on the crest of the Oak Ridges Moraine between Stouffville and Pontypool, Ontario. It is suggested that the most likely explanation for the submergence of that part of the moraine is that the Lake Ontario ice lobe was still overriding the Niagara Escarpment at the time, holding standing water in the area between the southern and northern ice lobes and the escarpment. A stream channel over the escarpment, extending from northeast of Cheltenham to Acton and beyond, may have served as the outlet. This sill is high enough to have held water over the above-mentioned silts and clays. It is of interest that this outlet channel led eventually to glacial Lake Whittlesey, indicating a correlation.

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