Geology and age of the Precambrian basement in the Windsor, Chatham, and Sarnia area, southwestern Ontario

1982 ◽  
Vol 19 (8) ◽  
pp. 1627-1634 ◽  
Author(s):  
A. Turek ◽  
R. N. Robinson
Keyword(s):  
Oil And Gas ◽  
Precambrian Basement ◽  
Grenville Province ◽  
Metasedimentary Rocks ◽  
Gas Drilling ◽  
Arch System ◽  
Grenvillian Orogeny ◽  
Anomaly Map ◽  
Paleozoic Rocks ◽  
Basement Surface

Precambrian basement in the Windsor–Chatham–Sarnia area is covered by Paleozoic rocks that are up to 1300 m thick. The basement surface is characterized by a northeast–southwest arch system with a relief of about 350 m. Extensive oil and gas drilling has penetrated and sampled this basement, and an examination of core and chip samples from 133 holes and an assessment of the magnetic anomaly map of the area have been used to produce a lithologic map of the Precambrian basement. The predominant rocks are granite gneisses and syenite gneisses but also significant are gabbros, granodiorite gneisses, and metasedimentary rocks. The average foliation dips 50° and is inferred to have a northeasterly trend. The Precambrian basement has been regarded as part of the Grenville Province. An apparent Rb–Sr whole rock isochron, for predominantly meta-igneous rocks, yields an age of 1560 ± 140 Ma. This we interpret as pre-Grenvillian, surviving the later imprint of the Grenvillian Orogeny. Points excluded from the isochron register ages of 1830, 915, and 670 Ma, and can be interpreted as geologically meaningful.

A Discussion on global tectonics in Proterozoic times - The Grenville Province in Helikian times: a possible model of evolution

1976 ◽  
Vol 280 (1298) ◽  
pp. 499-515 ◽  
Keyword(s):  
Continental Crust ◽  
Granulite Facies ◽  
Continental Collision ◽  
Canadian Shield ◽  
Grenville Province ◽  
East Central ◽  
Metasedimentary Rocks ◽  
Grenvillian Orogeny ◽  
Triangular Area ◽  
Global Tectonics

It is suggested that the Helikian (1650-1000 million years (Ma) ago) evolution of the Grenville Province in the Canadian Shield was marked by three events: emplacement of anorthosites around 1450-1500 Ma ago, rifting associated with opening of a proto-Atlantic ocean between 1200 and 1300 Ma ago, and continental collision responsible for the Grenvillian ‘orogeny’ about 1100-1000 Ma ago. Emplacement of rocks of the anorthosite suite (anorthosites and adamellites or mangerites) into continental crust was accompanied by formation of aureoles in the granulite facies. The Grenville Group was deposited in the southern part of the Province between 1300 and 1200 Ma ago and comprises marbles, clastic metasedimentary rocks and volcanics. It occupies a roughly triangular area limited on the northwest by the Bancroft—Renfrew lineament and on the southeast by the Chibougamau—Gatineau lineament. It is thought to have been accumulated in an aulacogen that would have developed along a fracture zone separating two basement blocks. The Grenvillian thermotectonic event may represent a Tibetan continental collision in the sense of Burke & Dewey. The suture zone would now be hidden under the Appalachians. Collision would cause reactivation of continental crust and renewed movement on pre-existing lineaments. The east—central part of the Grenville Province appears to have been more intensively reactivated than the western part.

Geology and Ages of Buried Precambrian Basement Rocks, Manitoulin Island, Ontario

1975 ◽  
Vol 12 (7) ◽  
pp. 1175-1189 ◽  
Author(s):  
W. R. Van Schmus ◽  
K. D. Card ◽  
K. L. Harrower
Keyword(s):  
Granitic Rocks ◽  
Precambrian Basement ◽  
Aeromagnetic Data ◽  
Grenville Province ◽  
Metasedimentary Rocks ◽  
Basement Rocks ◽  
Metavolcanic Rocks ◽  
Northern Half ◽  
East End ◽  
Archean Basement

The geology of the buried Precambrian basement under Manitoulin Island in northern Lake Huron, Ontario, has been re-evaluated on the basis of aeromagnetic data, well cuttings, core samples, and rubidium–strontium and uranium–lead geochronologic data on some of the subsurface samples. We conclude that the northern half of the island is underlain in part by Huronian metasedimentary rocks, but that these are absent from the southern part of the island, which is underlain by granitic, gneissic, and metavolcanic rocks. Granitic and gneissic rocks are also present under the northern half of the island.Geochronologic data show that rocks underlying major positive aeromagnetic anomalies are quartz-monzonitic composite plutons which are about 1500 ± 20 m.y. old. Surrounding metasedimentary. gneissic, and granitic rocks are at least 1700 m.y. old. No evidence was found for extrapolation of the pre-Huroman Archean basement beneath Manitoulin Island; if it is present it has been affected by younger metamorphic overprinting.The south west ward extension of the boundary zone between the Grenville Province and rocks to the west can he traced along the east end of Manitoulin Island on the basis of aeromagnetic data.

Metamorphic constraints on the evolution of the gneisses from the parautochthonous and allochthonous polycyclic belts, Grenville Province, western Quebec

1990 ◽  
Vol 27 (3) ◽  
pp. 357-370 ◽  
Author(s):  
A. Indares ◽  
J. Martignole
Keyword(s):  
Granulite Facies ◽  
Ultramafic Rocks ◽  
Significant Discrepancy ◽  
Grenville Province ◽  
Narrow Strip ◽  
Metasedimentary Rocks ◽  
Metamorphic History ◽  
Tectonic Transport ◽  
History Of ◽  
Grenvillian Orogeny

The tectono-metamorphic history of polycyclic "grey gneisses" located in the central Grenville Province of western Quebec has been constrained along a transect perpendicular to the length of the Grenville Orogen. Two terranes, the Réservoir Dozois terrane (RDT) and the Réservoir Baskatong terrane (RBT), were recognized from their structural, lithological, and geochronological characteristics. This subdivision has been confirmed by application of geothermobarometric techniques to appropriate mineral assemblages.The RDT is the southern extension of the parautochthonous belt of the Grenville Province, which in this area is composed of Archean rocks of upper-amphibolite grade. During the Grenvillian Orogeny, northwest-directed thrusting resulted in the tectonic burial of this terrane as a single tectonic unit, in contrast with the northern part of the parautochthonous belt, where several slices were imbricated against the Grenville Front. Maximum P–T conditions in the RDT (850 MPa, 720 °C) were likely Grenvillian and were followed by pervasive retrogression down to the hornblende–epidote subfacies. Locally, the RDT is overlain by remnants of thrust slices composed of monocyclic metasedimentary rocks that were deformed and metamorphosed in the granulite facies during the Grenvillian Orogeny.To the southeast, the RBT is an allochthonous or exotic terrane probably of Proterozoic age. It also experienced tectonic burial by thrusting (1030 MPa, 710 °C) during the Grenvillian Orogeny, whose thermal climax (790 °C) coincided with charnockite emplacement during decompression to 850 MPa.These two terranes are separated by a narrow strip of sheared rocks, the Renzy shear belt (RSB), which comprises mafic and ultramafic rocks subjected to high P and T (975 MPa, 745 °C). In view of the significant discrepancy between the metamorphic histories of the two terranes separated by the RSB, major tectonic transport has to be envisaged along this zone.

Finite Element Study of the Cutting Mechanics of the Three Dimensional Rock Turning Process

2015 ◽  
Author(s):  
Demeng Che ◽  
Jacob Smith ◽  
Kornel F. Ehmann
Keyword(s):  
Finite Element ◽  
Oil And Gas ◽  
Three Dimensional ◽  
Polycrystalline Diamond ◽  
Close Correlation ◽  
Experimental Results ◽  
Failure Behavior ◽  
Fe Model ◽  
Gas Drilling ◽  
Cutting Mechanics

The unceasing improvements of polycrystalline diamond compact (PDC) cutters have pushed the limits of tool life and cutting efficiency in the oil and gas drilling industry. However, the still limited understanding of the cutting mechanics involved in rock cutting/drilling processes leads to unsatisfactory performance in the drilling of hard/abrasive rock formations. The Finite Element Method (FEM) holds the promise to advance the in-depth understanding of the interactions between rock and cutters. This paper presents a finite element (FE) model of three-dimensional face turning of rock representing one of the most frequent testing methods in the PDC cutter industry. The pressure-dependent Drucker-Prager plastic model with a plastic damage law was utilized to describe the elastic-plastic failure behavior of rock. A newly developed face turning testbed was introduced and utilized to provide experimental results for the calibration and validation of the formulated FE model. Force responses were compared between simulations and experiments. The relationship between process parameters and force responses and the mechanics of the process were discussed and a close correlation between numerical and experimental results was shown.

Oil and Gas Drilling Optimization Technologies Applied Successfully to Unconventional Geothermal Well Drilling

2021 ◽  
Author(s):  
Junichi Sugiura ◽  
Ramon Lopez ◽  
Francisco Borjas ◽  
Steve Jones ◽  
John McLennan ◽  
...  
Keyword(s):  
Geothermal Energy ◽  
Oil And Gas ◽  
Optimization Techniques ◽  
Geothermal System ◽  
Well Drilling ◽  
Geothermal Well ◽  
Gas Drilling ◽  
Drilling Tools ◽  
Drilling Optimization ◽  
Oil And Gas Drilling

Abstract Geothermal energy is used in more than 20 countries worldwide and is a clean, reliable, and relatively available energy source. Nevertheless, to make geothermal energy available anywhere in the world, technical and economic challenges need to be addressed. Drilling especially is a technical challenge and comprises a significant part of the geothermal development cost. An enhanced geothermal system (EGS) is a commercially viable thermal reservoir where two wells are interconnected by some form of hydraulic stimulation. In a commercial setting, fluid is injected into this hot rock and passes between wells through a network of natural and induced fractures to transport heat to the surface system for electricity generation. To construct EGS wells, vertical and directional drilling is necessary with purpose-built drilling and steering equipment. This is an application where oil-and-gas drilling tools and techniques can be applied. A recent well, 16A(78)-32, drilled as part of the US Department of Energy's (DOE's) Utah Frontier Observatory for Research in Geothermal Energy (FORGE) program, highlights some of the technical challenges, which include drilling an accurate vertical section, a curve section, and a 5300-ft 65° tangent section in a hard granitic formation at temperatures up to 450°F (232°C). Extensive downhole temperature simulations were performed to select fit-for-purpose drilling equipment such as purely mechanical vertical drilling tools, instrumented steerable downhole motors, measurement-while-drilling (MWD) tools, and embedded high-frequency drilling dynamics recorders. Downhole and surface drilling dynamics data were used to fine- tune bit design and motor power section selection and continuously improve the durability of equipment, drilling efficiency, and footage drilled. Drilling optimization techniques used in oil and gas settings were successfully applied to this well, including analysis of data from drilling dynamics sensors embedded in the steerable motors and vertical drilling tools, surface surveillance of mechanical specific energy (MSE), and adopting a drilling parameter roadmap to improve drilling efficiency to minimize drilling dysfunctions and equipment damages. Through drilling optimization practices, the instrumented steerable motors with proper bit selections were able to drill more than 40 ft/hr on average, doubling the rate of penetration (ROP), footage, and run length experienced in previous granite wells. This paper presents a case study in which cutting-edge oil-and-gas drilling technologies were successfully applied to reduce the geothermal well drilling time by approximately half.

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