Style and intensity of late Cenozoic deformation in the Nagoorin Basin (eastern Queensland, Australia) and implications for the pattern of strain in an intraplate setting

AbstractEastern Australia was affected by late Cenozoic intraplate deformation in response to far-field stress transmitted from the plate boundaries, but little is known about the intensity and pattern of this deformation. We used recently surveyed two-dimensional seismic reflection lines and aeromagnetic data, and data from the recently released Australian Stress Map, to investigate the structure of the Nagoorin Basin in eastern Queensland. The western margin of the Nagoorin beds was displaced by the Boynedale Fault, which is a NNW-striking SW-dipping oblique strike-slip reverse fault with a vertical throw ofc.900 m andc.16 km sinistral displacement. A significant part of this large sinistral displacement is interpreted to have occurred prior to late Cenozoic time. Several low-angle (<30°) thin-skinned thrusts with a flat-ramp geometry also displaced the Nagoorin beds, which are interpreted to have developed along detachment surfaces in oil shales and claystone. The Boynedale Fault is a segment within longer NNW-striking faults that include the North Pine and West Ipswich fault systems in eastern Queensland. These NNW-striking faults are potentially active, and may accommodate neotectonic thrust movement in response to the present-day NE–SW orientation of SHmax. Results of this study, in conjunction with previous information on sedimentary basins in eastern Australia, indicate that Cenozoic contractional deformation is stronger at the continental margins, possibly due to the presence of pre-existing rift-related structures.

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Grenville Foreland Deformation and Sedimentation in Southwest Ohio Indicated by Reprocessed Seismic Reflection Profiles near Middletown, Ohio, USA

The Ohio Journal of Science ◽

10.18061/ojs.v120i2.7260 ◽

2020 ◽

Vol 120 (2) ◽

pp. 39

Author(s):

David J. Peterman ◽

Ernest C. Hauser ◽

Doyle R. Watts

Keyword(s):

Cross Section ◽

Seismic Reflection ◽

Vertical Displacement ◽

Reverse Fault ◽

Seismic Line ◽

The North ◽

North American Craton ◽

Tectonic Style ◽

Seismic Reflection Profiles ◽

Depositional Setting

The late Mesoproterozoic to early Neoproterozoic Middle Run Formation contains vital information about the crustal evolution of the North American Craton. Four reprocessed seismic reflection lines in the vicinity of the AK Steel facility in Middletown, Ohio, provide new insights into the structural and depositional setting of the Middle Run Formation in this region. A residual statics solution improved the resolution and coherency of reflections in these profiles that underlie the Cambrian Mount Simon Sandstone. Reprocessing revealed gently inclined, west-southwest-dipping reflectors and the occurrence of an angular unconformity between the Middle Run Formation and the overlying Paleozoic strata. The weak and discontinuous seismic reflection character of the Middle Run Formation in these seismic lines overlies a sequence of stronger parallel reflections that are like those observed on the eastward ODNR-1-88 seismic line located near core hole DGS 2627, the stratotype of the Middle Run Formation. This inferred thickness indicates that the basin in which the Middle Run Formation was deposited ranges from at least 670 to 1,128 m (2,200 to 3,700 ft) deep at the AK Steel area and dips gently west-southwest, which is in contrast with the moderate easterly dip observed on the ODNR-1-88 seismic line to the northeast. Correlation of these features across the 10 km (approximately 6 mi) cross-strike gap between the AK Steel lines and the ODNR-1-88 seismic line suggests the presence of a reverse fault with approximately 792 m (2,600 ft) of estimated vertical displacement. A regional cross section—including the WSU 1990 seismic line eastward of the ODNR-1-88 line—exhibits a faulted west-verging asymmetric syncline in near proximity to the Grenville Front. This cross section also shows that deformation of the Middle Run Formation and the underlying layered sequence exhibits a consistent tectonic style of reverse faulting and folding that developed in response to Grenville Front tectonism.

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Geology and prospects of oil and gas bearing of east — Canadian continental margins

Океанология ◽

10.31857/s0030-1574594656-669 ◽

2019 ◽

Vol 59 (4) ◽

pp. 656-669

Author(s):

A. Zabanbark ◽

L. I. Lobkovsky

Keyword(s):

Nova Scotia ◽

Continental Margin ◽

Late Cretaceous ◽

Oil And Gas ◽

Sedimentary Basins ◽

Wide Distribution ◽

Labrador Sea ◽

Continental Margins ◽

The North ◽

Gas Bearing

At the limit of the East-Canadian continental margin there are three oil and gas regions from north to south: Labrador Sea shelves, margins of the Great Newfoundland Bank and the continental margin of Nova Scotia. In each of these distinguishing regions are a number of sedimentary basins completely plunging under the water. At the shelf of Labrador Sea distinguishing the following large sedimentary basins: Saglek, Hopdale and Havke, at the margin of Newfoundland Bank it is known the basins: Jeanne d’Arc, Flemish Pass and Orphan. At the Nova Scotia shelf there are Nova Scotian and Sable basins. It is remarkable at the lofty latitude like of Labrador Sea region the age of the productive sediments beginning from more ancient rocks (Paleozoic), than in basins situated in law latitude (Mesozoic). In consequence of this the stratigraphy diapason of oil and gas bearing of the north latitude is considerably wide. The prospect of oil and gas bearing in all region is related principally with continental slopes and turbidites sediments in its. Late Jurassic and early Cretaceous reservoirs would be the aim for deep drilling sediments. Wide distribution of late Cretaceous and early Tertiary prospects reservoirs of oil and gas is quite really so far as they are bedded in the shallow horizons. Also the prospect of oil and gas bearing at the margin of the basin is related to late Cretaceous and Tertiary sediments, to deposits of fan and diapirs salt.

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Shallow seismic reflection imaging of the Inabanga–Clarin portion of the North Bohol Fault, Central Visayas, Philippines

Geoscience Letters ◽

10.1186/s40562-019-0139-x ◽

2019 ◽

Vol 6 (1) ◽

Author(s):

Romer Carlo T. Gacusan ◽

Alfredo Mahar Francisco A. Lagmay

Keyword(s):

Seismic Reflection ◽

Risk Mitigation ◽

High Surface ◽

Normal Faults ◽

Reverse Fault ◽

Flower Structure ◽

Seismic Profiles ◽

The North ◽

Shallow Seismic ◽

Earthquake Hazard Assessment

Abstract On 15 October 2013, a magnitude 7.2 earthquake was generated from a previously unidentified fault in the island of Bohol. This fault was named the North Bohol Fault (NBF) by authorities. We investigated the geometry of the Inabanga–Clarin portion of the NBF using three high-resolution shallow seismic reflection profiles to image sections of the fault up to 150 m depth not seen in trenching and regional offshore seismic profiles. These seismic profiles are along the Calubian, Napo, and Caluwasan transects which run perpendicular to the N$$40^{\circ }$$ 40 ∘ E strike of the NBF. Reverse faults were identified in the Calubian and Napo profiles, whereas a positive flower structure was seen in the Caluwasan profile. Normal faults were also identified in the Caluwasan and Napo profiles. This study corroborates the observations in earlier trenching studies that measured the reverse fault dip angle and direction of the NBF at $$70^{\circ }$$ 70 ∘ SE. It also demonstrates that topographic flexures are the surface manifestation of steeply dipping faults. The downthrown block of the reverse faults in the Calubian profile defines a depression on the surface; the Napo seismic profile displacement of 3 m is consistent with the 3-m-high surface rupture in Barangay Anonang; and the flower structure in the Caluwasan profile is related to the pressure ridge and right lateral offset stream on the surface. Furthermore, the presence of normal faults as well as the other deformational features is consistent with the transpressional regime described in the literature, wherein the principal horizontal stress is oriented NW–SE. These findings complement earlier geomorphic and trenching investigations of the NBF and demonstrate the application of a tool to image the subsurface and characterize undescribed or hidden faults, which is necessary for earthquake hazard assessment and attendant risk mitigation and prevention planning.

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A seismic reflection study of northern Baffin Bay: implication for tectonic evolution

Canadian Journal of Earth Sciences ◽

10.1139/e92-184 ◽

1992 ◽

Vol 29 (11) ◽

pp. 2353-2369 ◽

Cited By ~ 19

Author(s):

H. Ruth Jackson ◽

Kate Dickie ◽

François Marillier

Keyword(s):

Seismic Reflection ◽

Sedimentary Basins ◽

Baffin Island ◽

Seismic Profiles ◽

Plate Motions ◽

Baffin Bay ◽

Devon Island ◽

The North ◽

Tectonic Development ◽

Rifted Margin

Reflection profiles offshore of Baffin Island, south of Lancaster Sound, reveal coast-parallel half-grabens containing flat-lying sedimentary sections typical of a rifted margin. In northernmost Baffin Bay, adjacent to Devon and southern Ellesmere islands, four sedimentary basins are identified. In these basins the sedimentary sections are faulted, folded, and laterally discontinuous. The basement shows linear trends, steep faults, and abrupt variations in depth. In one basin a 50 km long and 10 km wide "flower structure" is observed. A transpressive tectonic regime is suggested to explain the uplifted sedimentary and basement section and the change in depth to basement across it. A 150 km long paleoshelf, buried by a thickening sedimentary wedge, is present offshore of Devon Island. Because strike-slip and compressional features are observed on seismic profiles north of Lancaster Sound and extensional features are observed to the south, differences in the plate tectonic development are inferred. The interpretations of the seismic reflection records are shown to be compatible with plate motions determined by matching magnetic anomalies in the North Atlantic, the Labrador Sea, the Norwegian and Greenland seas, and the Eurasia Basin. In addition, the onshore geology of Baffin Island, Labrador, and Greenland is consistent with the predrift position of the plates.

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Crustal structure across the Caledonides from the ‘WINCH’ seismic reflection profile: influences on the evolution of the Midland Valley of Scotland

Transactions of the Royal Society of Edinburgh Earth Sciences ◽

10.1017/s0263593300013766 ◽

1984 ◽

Vol 75 (2) ◽

pp. 97-109 ◽

Cited By ~ 88

Author(s):

J. Hall ◽

J. A. Brewer ◽

D. H. Matthews ◽

M. R. Warner

Keyword(s):

Crustal Structure ◽

Crustal Deformation ◽

Seismic Reflection ◽

Deep Structure ◽

Sedimentary Basins ◽

Seismic Reflection Profile ◽

Crustal Shortening ◽

The North ◽

Reflection Profile ◽

Deep Seismic Reflection Profile

ABSTRACTThe Western Isles–North Channel (‘WINCH’) deep seismic reflection profile runs through the North Channel across the extension of the Midland Valley into the Firth of Clyde.A variety of shallow Carboniferous and younger sedimentary basins dominates the upper crustal structure. The deep structure includes a reflective lower crust, bounded downwards by the Moho, and dipping ‘thrusts’. No margins to the Midland Valley are observed equivalent to the bounding faults on land. Thrusts below both the Highlands and the Southern Uplands have a variety of dip directions indicative of zig-zag crustal shortening of 100 km in the Highlands and 60 km in the Southern Uplands.The Moho varies only a little in depth, despite the gross crustal deformation in the Caledonides. Isostatic recovery of the Moho on unlocking of collided crustal blocks may explain the formation of some sedimentary basins.

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Data report for the North and South Richardson Highway profiles, TACT, seismic-reflection Survey, southern Alaska

Open-File Report ◽

10.3133/ofr86274 ◽

1986 ◽

Cited By ~ 1

Author(s):

P.J. Meador ◽

E.L. Ambos ◽

G.S. Fuis

Keyword(s):

Seismic Reflection ◽

The North ◽

North And South

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Sedimentary basins at eastern Asian continental margins and oceanic regions

Open-File Report ◽

10.3133/ofr85265 ◽

1984 ◽

Cited By ~ 1

Author(s):

Frank F. Wang

Keyword(s):

Sedimentary Basins ◽

Continental Margins

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Hydrothermal activity in the Upper Permian Ravnefjeld Formation of central East Greenland – a study of sulphide morphotypes

Geological Survey of Denmark and Greenland Bulletin ◽

10.34194/ggub.v180.5090 ◽

1998 ◽

pp. 81-87

Author(s):

Jesper Kresten Nielsen ◽

Mikael Pedersen

Keyword(s):

Base Metal ◽

Early Period ◽

Sedimentary Basins ◽

Hydrothermal Activity ◽

Source Rocks ◽

Upper Permian ◽

Thermal Activity ◽

East Greenland ◽

The North ◽

Alum Shale

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Kresten Nielsen, J., & Pedersen, M. (1998). Hydrothermal activity in the Upper Permian Ravnefjeld Formation of central East Greenland – a study of sulphide morphotypes. Geology of Greenland Survey Bulletin, 180, 81-87. https://doi.org/10.34194/ggub.v180.5090 _______________ Bituminous shales of the Ravnefjeld Formation were deposited in the subsiding East Greenland basin during the Upper Permian. The shales are exposed from Jameson Land in the south (71°N; Fig. 1) to Clavering Ø in the north (74°20′N) and have attracted considerable attention due to their high potential as hydrocarbon source rocks (Piasecki & Stemmerik 1991; Scholle et al. 1991; Christiansen et al. 1992, 1993a, b). Furthermore, enrichment of lead, zinc and copper has been known in the Ravnefjeld Formation on Wegener Halvø since 1968 (Lehnert-Thiel 1968; Fig. 1). This mineralisation was assumed to be of primary or early diagenetic origin due to similarities with the central European Kupferschiefer (Harpøth et al. 1986). Later studies, however, suggested base metal mineralisation in the immediately underlying carbonate reefs to be Tertiary in age (Stemmerik 1991). Due to geographical coincidence between the two types of mineralisation, a common history is a likely assumption, but a timing paradox exists. A part of the TUPOLAR project on the ‘Resources of the sedimentary basins of North and East Greenland’ has been dedicated to re-investigation of the mineralisation in the Ravnefjeld Formation in order to determine the genesis of the mineralisation and whether or not primary or early diagenetic base metal enrichment has taken place on Wegener Halvø, possibly in relation to an early period of hydrothermal activity. One approach to this is to study the various sulphides in the Ravnefjeld Formation; this is carried out in close co-operation with a current Ph.D. project at the University of Copenhagen, Denmark. Diagenetically formed pyrite is a common constituent of marine shales and the study of pyrite morphotypes has previously been successful from thermalli immature parts of elucidating depositional environment and thermal effects in the Alum Shale Formation of Scandinavia (Nielsen 1996; Nielsen et al. 1998). The present paper describes the preliminary results of a similar study on pyrite from thermally immature parts of the Ravnefjeld Formation which, combined with the study of textures of base metal sulphides in the Wegener Halvø area (Fig. 1), may provide an important step in the evaluation of the presence or absence of early thermal activity on (or below) the Upper Permian sea floor.

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