Tectonic history of the Queen Charlotte Islands and adjacent areas—a model

1981 ◽  
Vol 18 (11) ◽  
pp. 1717-1739 ◽  
Author(s):  
C. J. Yorath ◽  
R. L. Chase
Keyword(s):  
Fault Zone ◽  
Upper Jurassic ◽  
Normal Faults ◽  
Queen Charlotte Islands ◽  
Tectonic History ◽  
History Of ◽  
Middle Component ◽  
High Level ◽  
Paleozoic Rocks ◽  
Alexander Terrane

The region including Queen Charlotte Islands, Hecate Strait, and Queen Charlotte Sound is underlain by two allochthonous terranes, Wrangellia and the Alexander terrane. The suture between them occurs in central Graham Island and central Hecate Strait and is coincident with the traces of the Sandspit and Rennell Sound fault zones, each of which developed in response to crustal rifting in Queen Charlotte Sound during mid-Tertiary time.The stratigraphic succession comprises four tectonic assemblages. (1) The allochthonous assemblages comprise Paleozoic rocks of the Alexander terrane and Upper Triassic and Jurassic rocks of Wrangellia, which on the basis of paleomagnetic and biogeographical data are clearly exotic. The distribution of these terranes beneath Queen Charlotte Sound and Hecate Strait is supported by geophysical information and subsurface data obtained from offshore wells. (2) The suture assemblage is represented by extremely coarse conglomerates, massive graywackes, and turbidites of Early Cretaceous age, and possibly by Upper Jurassic plutons. (3) The post-suture assemblage is expressed by the tripartite succession of the mid- to Upper Cretaceous Queen Charlotte Group whose middle component, the Honna Formation, comprises polymictic conglomerates that may have resulted from the final accretion of the amalgamated crustal fragments of the Alexander Terrane and Wrangellia to the continental margin. (4) The rift assemblage is expressed by mid- to upper Tertiary volcanics, epizonal plutons, and terrigenous clastics. Rifting is believed to have occurred in Queen Charlotte Sound above a mantle plume and resulted in crustal attenuation through development of listric, crustal-penetrative normal faults, and concurrent extrusion of subaerial volcanics and emplacement of high-level plutons. The attenuation caused northward motion of the Queen Charlotte Islands along the Louscoone Inlet – Sandspit fault zone and subsidence in Queen Charlotte Sound where Lower Miocene marine sediments were deposited within the rift zone. Later, additional rifting in southern Hecate Strait resulted in the reactivation of the old suture zone, manifest as the Rennell Sound fault zone. Concurrent with continued terrigenous deposition and volcanism, the Queen Charlotte Islands moved northwesterly along the Rennell Sound Fault, which disrupted the earlier fault trend. The final rotation of the islands to their modern position was accomplished through left-lateral motion along the Beresford Bay and Langara Faults.

scholarly journals Tectonic history of the eastern edge of the Alexander Terrane, southeast Alaska

Tectonics ◽  
1992 ◽  
Vol 11 (3) ◽  
pp. 586-602 ◽  
Author(s):  
Charles M. Rubin ◽  
Jason B. Saleeby
Keyword(s):  
Southeast Alaska ◽  
Tectonic History ◽  
History Of ◽  
Eastern Edge ◽  
Alexander Terrane

Faulting of a Middle Jurassic, ultramafic dyke in the Picton Quarry, Picton, southern Ontario

1990 ◽  
Vol 27 (11) ◽  
pp. 1536-1540 ◽  
Author(s):  
G. H. McFall
Keyword(s):  
Fault Zone ◽  
Middle Jurassic ◽  
Southern Ontario ◽  
Prince Edward County ◽  
Dyke Rock ◽  
Tectonic History ◽  
History Of ◽  
East West

A fault zone coinciding with a Middle Jurassic, ultramafic dyke exposed in the Picton Quarry in Prince Edward County, Ontario, is marked by steeply dipping, generally east–west-striking fractures. The dyke has been affected by faulting, as evidenced by the presence of subhorizontal slickensides on fractures cutting the dyke rock. This discovery constitutes the first known example of Middle Jurassic or younger faulting having affected Paleozoic strata of southern Ontario and indicates that the structural and tectonic history of the region is more complex than commonly believed.

scholarly journals Late Cretaceous to Paleogene post-obduction extension and subsequent Neogene compression in the Oman Mountains

GeoArabia ◽  
2006 ◽  
Vol 11 (4) ◽  
pp. 17-40 ◽  
Author(s):  
Marc Fournier ◽  
Claude Lepvrier ◽  
Philippe Razin ◽  
Laurent Jolivet
Keyword(s):  
Late Cretaceous ◽  
Large Scale ◽  
Early Miocene ◽  
Normal Faults ◽  
Zagros Mountains ◽  
Lower Eocene ◽  
Oman Mountains ◽  
Tectonic History ◽  
History Of ◽  
Arabian Platform

ABSTRACT After the obduction of the Semail ophiolitic nappe onto the Arabian Platform in the Late Cretaceous, north Oman underwent several phases of extension before being affected by compression in the framework of the Arabia-Eurasia convergence. A tectonic survey, based on structural analysis of fault-slip data in the post-nappe units of the Oman Mountains, allowed us to identify major events of the Late Cretaceous and Cenozoic tectonic history of northern Oman. An early ENE-WSW extensional phase is indicated by synsedimentary normal faults in the Upper Cretaceous to lower Eocene formations. This extensional phase, which immediately followed ductile extension and exhumation of high-pressure rocks in the Saih Hatat region of the Oman Mountains, is associated with large-scale normal faulting in the northeast Oman margin and the development of the Abat Basin. A second extensional phase, recorded in lower Oligocene formations and only documented by minor structures, is characterized by NNE (N20°E) and NW (N150°E) oriented extensions. It is interpreted as the far-field effect of the Oligocene-Miocene rifting in the Gulf of Aden. A late E-W to NE-SW directed compressional phase started in the late Oligocene or early Miocene, shortly after the collision in the Zagros Mountains. It is attested by folding, and strike-slip and reverse faulting in the Cenozoic series. The direction of compression changed from ENE-WSW in the Early Miocene to almost N-S in the Pliocene.

scholarly journals Offshore bedrock geology of Eclipse Sound and Pond Inlet: connecting the structure and stratigraphy of Bylot and northern Baffin islands

2020 ◽  
Vol 57 (10) ◽  
pp. 1254-1267
Author(s):  
Lisel D. Currie ◽  
Tom A. Brent ◽  
Elizabeth C. Turner
Keyword(s):  
Fault Zone ◽  
Active Faults ◽  
Petroleum Exploration ◽  
Normal Faults ◽  
Sea Floor ◽  
Baffin Bay ◽  
Bay Area ◽  
History Of ◽  
Marine Seismic ◽  
Fault Displacement

Understanding the Mesoproterozoic and younger structural history of the Eclipse Sound/Pond Inlet area is essential for the interpretation of its Archean to Paleoproterozoic geological history and could have important implications for mineral and petroleum exploration models in the northern Baffin Bay area. The identification of potentially active faults is critical for understanding possible earthquake-related hazards in the area. The integrated interpretation of 1970s-vintage marine seismic data with hill-shaded bathymetry, aeromagnetic data, and onshore geology maps has facilitated the identification of probable Mesoproterozoic (Bylot Supergroup) to Holocene strata on and below the sea floor and a suite of episodically reactivated northwest-striking horst- and graben-bounding normal faults and fault zones. Fault displacement likely occurred during the development of the Mesoproterozoic Borden basin and the Cretaceous–Paleogene opening of Baffin Bay, and in some cases may continue today. Some faults become more west-trending toward the south, which requires parts of these faults to have intermittently accommodated transtensional and (or) transpressional motion, possibly explaining local folds and out-of-graben thrusting. Numerous previously unrecognised faults have been documented, with faults beneath Eclipse Sound (Eclipse Trough) spaced at 5 to 7 km intervals, and at least one fault zone (Cape Hay Fault Zone) that appears to be at least 250 km in length, suggesting faults of similar spacing and scale may be present under Baffin Bay. This study uses a multi-thematic office-based methodology that inexpensively, and with little environmental impact, facilitates the mapping of structures that intersect the sea floor in areas where glaciers have exposed bedrock.

STRUCTURAL ANALYSIS OF THE WICHITA UPLIFT AND STRUCTURES IN THE ANADARKO BASIN, SOUTHERN OKLAHOMA

2020 ◽  
pp. 1-51 ◽  
Author(s):  
Molly Turko ◽  
Shankar Mitra
Keyword(s):  
Normal Faults ◽  
Anadarko Basin ◽  
Tectonic History ◽  
Arbuckle Group ◽  
Southern Oklahoma ◽  
Northwestern Margin ◽  
History Of ◽  
Regional Stresses ◽  
Surface Geology ◽  
2D And 3D

We have constructed regional structural transects across the Wichita Uplift and adjacent Anadarko Basin to show the relationship between thick-skinned basement-involved structures and thin-skinned detached fold-thrust structures. Slip from the basement-involved structures in the Wichita Uplift is transferred along two major detachments into the Anadarko Basin. Our interpretation is that along the northwestern margin, the Wichita Uplift is marked by a zone of frontal imbricates forming a triangular wedge with most of the slip dissipated along the Wichita front. Paleozoic units show tight folding with overturned beds in the frontal zone. The uplift is episodic as indicated by the truncation of major faults along unconformities and their subsequent reactivation. In contrast, along the southeast margin, a significant part of the slip is transferred into structures in the Anadarko Basin. These structures are tight faulted-detachment folds that formed above a major detachment within the Springer Shale, cored by broader structures detaching at the base of the Arbuckle Group. Examples include the Carter-Knox, Cement-Chickasha, and Cruce structures. Oblique faults with normal and strike-slip components cut some of these structures, resulting in more complex geometries. We propose that pre-existing normal faults of Precambrian-Cambrian age were either reactivated along the Wichita Uplift, or controlled the location of the Pennsylvanian age structures in the Anadarko Basin. Progressive rotation of regional stresses from northeast-southwest to a more east-northeast-west-southwest direction during the Pennsylvanian impacted the tectonic history of the area. We used 2D and 3D seismic, well log data, and surface geology were used to evaluate the structural styles and tectonic evolution of the Wichita Uplift and the Anadarko Basin.

Histoire de l'evolution tectonique de la zone plissee alpine de l'Europe orientale et de l'Asie-Mineure

1962 ◽  
Vol S7-IV (2) ◽  
pp. 182-200
Author(s):  
M. V. Muratov
Keyword(s):  
Middle Eocene ◽  
Eastern Mediterranean ◽  
Early Period ◽  
Upper Jurassic ◽  
The Black Sea ◽  
Second Phase ◽  
Tectonic History ◽  
Third Phase ◽  
History Of ◽  
Second Period

Abstract Recent literature on the tectonic evolution of the Alpine chain in eastern Europe and Asia Minor is reviewed. Two major periods are recognized in describing the tectonic history of the region. The first embraces all the Paleozoic, ending with the Hercynian orogeny, and probably represents an early period of geosynclinal evolution. The second period is represented by a geosynclinal stage, including the Mesozoic and part of the Paleogene up to the end of the Oligocene, and a terminal stage of orogenesis embracing the Neogene and Quaternary. The geosynclinal stage of the second period can be divided into three phases--an early phase embracing the Triassic, lower and middle and perhaps the upper Jurassic and Cretaceous, and characterized by formation of the first Triassic basins on the peneplaned Paleozoic landscape; a second phase, Cretaceous-middle Eocene, characterized by enlargement of the geosynclines and deposition of flysch; and a third phase which began after the end of the middle Eocene, characterized by closing of the geosynclines. Oceanic trenches which developed in the Black Sea and the southern Caspian, Marmara, Aegean, Ionian and eastern Mediterranean seas are recent structures not connected with the geosynclinal evolution and are superimposed on the continental surface of the geosynclinal structures. The arrangement of the depressions and the uplift during the geosynclinal stage were determined by abyssal faults imposed during the Paleozoic. Magmatic intrusions and volcanism developed in the late geosynclinal phases.

scholarly journals Evolution of ancient Lake Ohrid: a tectonic perspective

2010 ◽  
Vol 7 (10) ◽  
pp. 3377-3386 ◽  
Author(s):  
N. Hoffmann ◽  
K. Reicherter ◽  
T. Fernández-Steeger ◽  
C. Grützner
Keyword(s):  
Hydrothermal Activity ◽  
Normal Faults ◽  
Lake Ohrid ◽  
Tectonic History ◽  
Neogene Sediments ◽  
History Of ◽  
Basin Formation ◽  
Hazard Level ◽  
Yugoslavian Republic ◽  
Tectonic Features

Abstract. Lake Ohrid Basin is a graben structure situated in the Dinarides at the border of the Former Yugoslavian Republic of Macedonia (FYROM) and Albania. It hosts one of the oldest lakes in Europe and is characterized by a basin and range-like geological setting together with the halfgraben basins of Korca, Erseka and Debar. The basin is surrounded by Paleozoic metamorphics in the northeast and north and Mesozoic ultramafic, carbonatic and magmatic rocks in the east, northwest, west and south. Paleocene to Pliocene units are present in the southwest. With the basin development, Neogene sediments from Pliocene to recent deposited in the lows. There are three major deformation phases: (A) NW–SE shortening from Late Cretaceous to Miocene; (B) uplift and diminishing compression during Messinian – Pliocene; (C) vertical uplift and (N)E–(S)W extension from Pliocene to recent led to the basin formation. Neotectonic activity of the study area concentrates on N–S trending normal faults that bound the Ohrid Basin eastwards and westwards. Seismic activity with moderate to strong events is documented during the last 2000 yrs; the seismic hazard level is among the highest in Albania and Macedonia. Activity of the youngest faults is evidenced by earthquake data and field observations. Morphotectonic features like fault scarps, a stepped series of active normal faults, deformed paleosols, a wind gap and fault-related hydrothermal activity are preserved around Lake Ohrid and allow delineating the tectonic history. It is shown that the Lake Ohrid Basin can be characterized as a seismogenic landscape. This paper presents a tectonic history of the Lake Ohrid Basin and describes tectonic features that are preserved in the recent landscape. The analysis of morphotectonic features is used to derive the deformation history. The stratigraphy of the area is summarized and concentrates on the main units.

scholarly journals Analysis of Palaeogene strike-slip tectonics along the southern East Greenland margin (Sødalen area)

1969 ◽  
Vol 23 ◽  
pp. 65-68 ◽  
Author(s):  
Pierpaolo Guarnieri
Keyword(s):  
Structural Data ◽  
Field Work ◽  
Strike Slip ◽  
Normal Faults ◽  
Large Area ◽  
East Greenland ◽  
Tectonic History ◽  
History Of ◽  
Host Rocks ◽  
Greenland Margin

This paper describes structural data collected during field work in southern East Greenland, a region characterised by a complex tectonic history. Here, 3D photogeology based on aerial and oblique photographs using high-resolution photogrammetry of a 150 km2 area in Sødalen in southern East Greenland shows ESE–WNW-trending faults cross-cutting Paleocene rift structures and flexure-related normal faults. The kinematic analysis highlights oblique and left-lateral strike-slip movements along faults oriented 120°. Strike-slip and dip-slip kinematic indicators on the walls of the chilled contacts between alkaline E–W-oriented dykes and the volcanic host rocks suggest that the faults and dykes formed at the same time, or maybe the faults were re-activated at a later stage. Palaeostress analysis, performed by inversion of fault-slip data, shows the presence of three different tectonic events. Coupling the 3D photogeological tool with structural analysis at key localities is a fundamental way to understand better the tectonic history of such a large area.

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