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Journal articles on the topic 'Failed rifts'

Author: Grafiati

Published: 10 December 2022

Last updated: 29 January 2023

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1

Anfiloff, V. "The effect of vertical crustal fractures on the rifting process." Exploration Geophysics 20, no. 2 (1989): 175. http://dx.doi.org/10.1071/eg989175.

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In the past, rifts have mainly been identified in terms of sediment troughs. They account for many of the elongate gravity lows distributed in a coherent rectilinear manner over the continent. Other gravity lows can be attributed to granites intruding rift compartments, and some gravity highs can be attributed to basic volcanics in compartments. The total number of rifts which can be thus inferred from gravity and magnetics is very large, and suggests rifting is pervasive over the whole continent and controlled by a systematically distributed "Cardinal" system of ancient vertical crustal fractures.The extensional concept of rifting is based on a finite number of rifts, all of which have "failed" to split the continent. When a far greater number of rifts is recognised, it becomes difficult to accept that all these rifts have "failed" to reach full opening by extensional processes. In view of the known horizontal compressive forces acting in the crust, it is more probable that rifting is caused by compression. The compartmentalization of rifts, clearly observed in gravity data, also implies compression.Closely spaced rectilinear dyke systems in shield areas may also represent the pervasive "Cardinal" fracture system. In general, this system of orthogonal fractures poses problems for the detatchment rifting concept which assumes that transfer faults are formed at the time a rift forms, whereas they in all probability predate the rift, and owe their existence to a fundamental process operating when continental crust first formed.Two types of compressive rift models are discussed. One is associated with shear couples between widely spaced parallel fractures. The other is based on the concept of a crust cut by closely spaced fractures in which compression is propagated along a network of linked blocks. In both cases the development of basement ridges is a key issue.

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2

KNOTT, STEVEN D. "Gravity-driven crustal shortening in failed rifts." Journal of the Geological Society 158, no. 2 (2001): 193–96. http://dx.doi.org/10.1144/jgs.158.2.193.

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3

Crowder, E., N. Rawlinson, D. G. Cornwell, C. Sammarco, E. Galetti, and A. Curtis. "New insights into North Sea deep crustal structure and extension from transdimensional ambient noise tomography." Geophysical Journal International 224, no. 2 (2020): 1197–210. http://dx.doi.org/10.1093/gji/ggaa475.

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SUMMARY The deep crustal structure beneath the North Sea is poorly understood since it is constrained by only a few seismic reflection and refraction profiles. However, it is widely acknowledged that the mid to lower crust plays important roles in rift initiation and evolution, particularly when large-scale sutures and/or terrane boundaries are present, since these inherited features can focus strain or act as inhibitors to extensional deformation. Ancient tectonic features are known to exist beneath the iconic failed rift system of the North Sea, making it an ideal location to investigate the complex interplay between pre-existing regional heterogeneity and rifting. To this end, we produce a 3-D shear wave velocity model from transdimensional ambient seismic noise tomography to constrain crustal properties to ∼30 km depth beneath the North Sea and its surrounding landmasses. Major North Sea sedimentary basins appear as low shear wave velocity zones that are a good match to published sediment thickness maps. We constrain relatively thin crust (13–18 km) beneath the Central Graben depocentres that contrasts with crust elsewhere at least 25–30 km thick. Significant variations in crustal structure and rift symmetry are identified along the failed rift system that appears to be related to the locations of Laurentia–Avalonia–Baltica palaeoplate boundaries. We constrain first-order differences in structure between palaeoplates; with strong lateral gradients in crustal velocity related to Laurentia–Avalonia–Baltica plate juxtaposition and reduced lower crustal velocities in the vicinity of the Thor suture, possibly representing the remnants of a Caledonian accretionary complex. Our results provide fresh insight into the pivotal roles that ancient terranes can play in the formation and failure of continental rifts and may help explain the characteristics of other similar continental rifts globally.

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4

Stein, Seth, Carol A. Stein, Reece Elling, et al. "Insights from North America's failed Midcontinent Rift into the evolution of continental rifts and passive continental margins." Tectonophysics 744 (October 2018): 403–21. http://dx.doi.org/10.1016/j.tecto.2018.07.021.

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5

Peace, Alexander L., and J. Kim Welford. "Conjugate margins — An oversimplification of the complex southern North Atlantic rift and spreading system?" Interpretation 8, no. 2 (2020): SH33—SH49. http://dx.doi.org/10.1190/int-2019-0087.1.

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The prevalence of conjugate margin terminology and studies in the scientific literature is testimony to the contribution that this concept and approach has made to the study of passive margins, and more broadly extensional tectonics. However, when applied to the complex rift, transform, and spreading system of the southern North Atlantic (i.e., the passive margins of Newfoundland, Labrador, Ireland, Iberia, and southern Greenland), it becomes obvious that at these passive continental margin settings, additional geologic phenomena complicate this convenient description. These aspects include (1) the preservation of relatively undeformed continental fragments, (2) formation of transform systems and oblique rifts, (3) triple junctions (with rift and spreading axes), (4) multiple failed rift axes, (5) postbreakup processes such as magmatism, (6) localized subduction, and (7) ambiguity in identification of oceanic isochrons. Comparison of two different published reconstructions of the region indicates the ambiguity in conducting conjugate margin studies. This demonstrates the need for a more pragmatic approach to the study of continental passive margin settings where a greater emphasis is placed on the inclusion of these possibly complicating features in palinspastic reconstructions, plate tectonics, and evolutionary models.

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6

Peirce, John W., and Lev Lipkov. "Structural interpretation of the Rukwa Rift, Tanzania." GEOPHYSICS 53, no. 6 (1988): 824–36. http://dx.doi.org/10.1190/1.1442517.

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The Rukwa Rift lies between Lakes Tanganyika and Malawi in the western limb of the East Africa rift system. Because little was known about the rift's structure or hydrocarbon potential, Petro‐Canada International Assistance Corporation completed a 2150 station gravity survey as part of an assistance program for the Tanzanian Petroleum Development Corporation. The survey covered an area 165 km × 375 km, which included the entire rift valley and lake plus regional control on either side. Outcrops of Carboniferous‐Triassic conglomerate, coal, and limestone, as well as Cretaceous sandstone, occur along the southwestern edge of the rift. The younger section is presumed to be dominated by alluvial material. In the absence of any density control, the gravity data were modeled using clastic sedimentary fill, which yields minimum depth estimates. Alternate models with more shale in the section have also been tried. A rift model with two shale pulses corresponding to interrift times yielded maximum depths of about 10 km. An all‐shale model failed to converge because of insufficient mass contrast. The final interpretation was based on the gravity models and aeromagnetic data acquired in an earlier survey. The Rukwa Rift is a half‐graben bounded to the northeast by a listric normal fault (strike 130 degrees) with 7 km of throw. A younger fault system forms the southwestern side of the valley and creates a major structure with 3 km of relief. The divergent strike of the younger faulting appears to be related in some way to right lateral shear in the Rukwa region. The Rukwa Rift has all the elements needed to be considered highly prospective for oil from a lacustrine source. There is strong evidence to suggest that the history of the Rukwa Rift is long and complex, providing ample opportunity for establishment of such an environment. The analogy of the Sudan rifts and the reports of oil seeps elsewhere in the western rift system support such a hypothesis. All the other elements of structure, reservoir, seal, maturation, and timing can be reasonably inferred from the available information. Of course, seismic and drilling are needed to provide firm stratigraphic control to confirm these inferences.

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7

Choudhury, Pallabee, Sumer Chopra, Charu Kamra, and Archana Das. "New Insight into the Recent Earthquake Activity in North Cambay Basin, Western India: Seismological and Geodetic Perspectives." Bulletin of the Seismological Society of America 109, no. 6 (2019): 2240–51. http://dx.doi.org/10.1785/0120190126.

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Abstract The intraplate Gujarat region located at the trijunction of three failed rifts, Kachchh, Narmada, and Cambay, is one of the most seismically active intraplate regions of the world. Among these three, the Cambay basin has been investigated thoroughly for petroleum. However, the basin has not been studied from a seismotectonic perspective. For the past few years, the northern part of the Cambay basin is becoming active with reasonably frequent earthquake occurrences. In the past 10 yr, ∼995 earthquakes have been recorded from the region with a maximum magnitude up to 4.2. Most of the earthquakes are in the magnitude range 1–3. Since 2009, four Global Positioning System (GPS) stations have been in operation in the vicinity of the Cambay basin, and a maximum deformation of 1.8±0.1 mm/yr has been estimated. The GPS‐derived strain rates of ∼0.02–0.03 microstrain/yr are prevalent in the region. An average strain rate of 0.02 microstrain/yr in the region can generate an earthquake of magnitude 6.4. The focal mechanisms of the earthquakes have been mostly normal with strike‐slip component and corroborated by the geodetic strain tensors. Most of the seismicity is clustered in the basement ridges, striking along pre‐existing Precambrian trends that cross the Cambay basin. Complex geodynamics have developed around the northern part of the Cambay rift because of the various movements along several faults, presence of basement ridges, and subsurface plutonic bodies in a failed rift, which are creating stresses and causing earthquakes in this part of the rift. We postulated that the highly heterogeneous subsurface structure beneath the northern part of the Cambay rift is creating additional stress, which is superimposing on the regional stress field substantially, and this mechanism is plausibly facilitating the localized extensional tectonics in the region where compression is expected.

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8

Knott, S. D., A. Beach, A. I. Welbon, and P. J. Brockbank. "Basin inversion in the Gulf of Suez: implications for exploration and development in failed rifts." Geological Society, London, Special Publications 88, no. 1 (1995): 59–81. http://dx.doi.org/10.1144/gsl.sp.1995.088.01.05.

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9

Li, Yaqing, Aqeel Abbas, Chun-Feng Li, et al. "Numerical modeling of failed rifts in the northern South China Sea margin: Implications for continental rifting and breakup." Journal of Asian Earth Sciences 199 (September 2020): 104402. http://dx.doi.org/10.1016/j.jseaes.2020.104402.

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10

Tari, Gábor, Didier Arbouille, Zsolt Schléder, and Tamás Tóth. "Inversion tectonics: a brief petroleum industry perspective." Solid Earth 11, no. 5 (2020): 1865–89. http://dx.doi.org/10.5194/se-11-1865-2020.

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Abstract. Inverted structures provide traps for petroleum exploration, typically four-way structural closures. As to the degree of inversion, based on a large number of worldwide examples seen in various basins, the most preferred petroleum exploration targets are mild to moderate inversion structures, defined by the location of the null points. In these instances, the closures have a relatively small vertical amplitude but are simple in a map-view sense and well imaged on seismic reflection data. Also, the closures typically cluster above the extensional depocenters which tend to contain source rocks providing petroleum charge during and after the inversion. Cases for strong or total inversion are generally not that common and typically are not considered as ideal exploration prospects, mostly due to breaching and seismic imaging challenges associated with the trap(s) formed early on in the process of inversion. Also, migration may become tortuous due to the structural complexity or the source rock units may be uplifted above the hydrocarbon generation window, effectively terminating the charge once the inversion has occurred. Cases of inversion tectonics can be grouped into two main modes. A structure develops in Mode I inversion if the syn-rift succession in the preexisting extensional basin unit is thicker than its post-rift cover including the pre- and syn-inversion part of it. In contrast, a structure evolves in Mode II inversion if the opposite syn- versus post-rift sequence thickness ratio can be observed. These two modes have different impacts on the petroleum system elements in any given inversion structure. Mode I inversion tends to develop in failed intracontinental rifts and proximal passive margins, and Mode II structures are associated with back-arc basins and distal parts of passive margins. For any particular structure the evidence for inversion is typically provided by subsurface data sets such as reflection seismic and well data. However, in many cases the deeper segments of the structure are either poorly imaged by the seismic data and/or have not been penetrated by exploration wells. In these cases the interpretation in terms of inversion has to rely on the regional understanding of the basin evolution with evidence for an early phase of crustal extension by normal faulting.

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11

BATIZA, R., and D. A. VANKO. "Petrologic Evolution of Large Failed Rifts in the Eastern Pacific: Petrology of Volcanic and Plutonic Rocks from the Mathematician Ridge Area and the Guadalupe Trough." Journal of Petrology 26, no. 3 (1985): 564–602. http://dx.doi.org/10.1093/petrology/26.3.564.

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12

McDermott, Kenneth, Paul Bellingham, Rod Graham, et al. "Continental extension and break-up—using the Australian margins as a case study." APPEA Journal 55, no. 2 (2015): 399. http://dx.doi.org/10.1071/aj14034.

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The continental margins of Australia provide an excellent natural laboratory for investigations of continental extension and break-up, with examples of failed rifts, multi-phase extensional systems, and volcanic and non-volcanic margins. The thick sedimentary cover across large parts, however, has hindered understanding of the deep crustal and lithospheric structure due to poor imaging. ION Geophysical has acquired deep, long offset seismic data across Australia’s North West Shelf, as well as the Bight Basin on Australia’s southern margin. These programs provide unique imaging of the deep basement structures and the complete overlying sedimentary section, and across all of the terrains from continental crust to oceanic crust. The authors’ interpretation of these data will be discussed in the context of existing models for continental extension and break-up and the resulting implications for the petroleum system: Models of hyper-extension and possible mantle exhumation will be discussed with regards to the Bonaparte, Browse and Bight basins. Multi-phase extension and the development of intra-sedimentary detachment horizons will be reviewed across many areas. Development of volcanic margins, including the effects of dynamic uplift and magmatic intrusions, will be investigated in the Exmouth Plateau. Creation of enough accommodation space to allow the deposition of the observed (~20 km) sedimentary sections in the Carnarvon and Bonaparte basins.

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13

Ross, Emma. "Command and control of Sierra Leone's Ebola outbreak response: evolution of the response architecture." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1721 (2017): 20160306. http://dx.doi.org/10.1098/rstb.2016.0306.

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Management, coordination and logistics were critical for responding effectively to the Ebola outbreak in Sierra Leone, and the duration of the epidemic provided a rare opportunity to study the management of an outbreak that endured long enough for the response to mature. This qualitative study examines the structures and systems used to manage the response, and how and why they changed and evolved. It also discusses the quality of relationships between key responders and their impact. Early coordination mechanisms failed and the President took operational control away from the Ministry of Health and Sanitation and established a National Ebola Response Centre, headed by the Minister of Defence, and District Ebola Response Centres. British civilian and military personnel were deeply embedded in this command and control architecture and, together with the United Nations Mission for Ebola Emergency Response lead, were the dominant coordination partners at the national level. Coordination, politics and tensions in relationships hampered the response, but as the response mechanisms matured, coordination improved and rifts healed. Simultaneously setting up new organizations, processes and plans as well as attempting to reconcile different cultures, working practices and personalities in such an emergency was bound to be challenging. This article is part of the themed issue ‘The 2013–2016 West African Ebola epidemic: data, decision-making and disease control’.

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14

W-Gabriel, Giday, and James L. Aronson. "Chow Bahir rift: A “failed” rift in southern Ethiopia." Geology 15, no. 5 (1987): 430. http://dx.doi.org/10.1130/0091-7613(1987)15<430:cbrafr>2.0.co;2.

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15

Lowe, Donald R. "Ouachita trough: Part of a Cambrian failed rift system." Geology 13, no. 11 (1985): 790. http://dx.doi.org/10.1130/0091-7613(1985)13<790:otpoac>2.0.co;2.

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16

Mahesh, P., V. K. Gahalaut, J. K. Catherine, et al. "Localized crustal deformation in the Godavari failed rift, India." Earth and Planetary Science Letters 333-334 (June 2012): 46–51. http://dx.doi.org/10.1016/j.epsl.2012.04.008.

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17

Liu, Yutao, Chun-Feng Li, Yonglin Wen, et al. "Mantle serpentinization beneath a failed rift and post-spreading magmatism in the northeastern South China Sea margin." Geophysical Journal International 225, no. 2 (2021): 811–28. http://dx.doi.org/10.1093/gji/ggab006.

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SUMMARY The post-spreading magmatic activities in the northeastern South China Sea (SCS) margin are very strong, evidenced by widely distributed high-velocity lower crust (HVLC) and numerous volcanoes. However, there are large contrasts in magmatic activities and crustal structure between the Southern Depression (TSD) of the Tainan Basin and the volcanic continental slope area further south. We analyse their crustal P-wave velocity structures based on a newly acquired wide-angle ocean bottom seismic data set. The Cenozoic strata below the TSD, a Cenozoic failed rift, are relatively thick (∼3–4.5 km) with velocities from 1.6 to 3.6–3.9 km s–1, whereas the Mesozoic strata are relatively thin (∼1–2.5 km) with velocities from 4.3 to 4.6–5.2 km s–1. In the TSD, magmatic activities are relatively weak and the crust is severely thinned (∼4 km). The crust is 9–15 km thick below the volcanic continental slope area, which shows extensive volcanism. We identified HVLC below the failed rift of the TSD (Zone 1) and attributed it to mantle serpentinization, whereas the imaged HVLC below the volcanic continental slope (Zone 3) and HVLC adjacent to the failed rift of the TSD (Zone 2) are due to post-spreading magmatic underplating/intrusions. At the model distance ∼90 km, lateral transition from magmatic underplating/intrusions to mantle serpentinization occurred abruptly. We concur that post-spreading cooling and thermal contraction in the nearby SCS oceanic lithosphere can trigger decompressive melting and deformation in the thinned continental slope zone. Our study shows that, in addition to mantle serpentinization in the continent–ocean transition (COT) zone, mantle can also be serpentinized below the rift during early-stage rifting. Weak syn-rifting magmatism and mantle serpentinization below the failed rift support that the northeastern SCS has a magma-poor margin.

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Welford, J. Kim, Sonya A. Dehler, and Thomas Funck. "Crustal velocity structure across the Orphan Basin and Orphan Knoll to the continent–ocean transition, offshore Newfoundland, Canada." Geophysical Journal International 221, no. 1 (2019): 37–59. http://dx.doi.org/10.1093/gji/ggz575.

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SUMMARY Orphan Basin, a massive deepwater rifted basin off the northeastern coast of Newfoundland, was one of the targets of the 2009 SIGNAL (Seismic Investigations off Greenland, Newfoundland and Labrador) experiment to collect refraction/wide-angle reflection (RWAR) data from the Bonavista Platform, through the Orphan Basin, to the Orphan Knoll, and beyond into oceanic crust. Both the data from an earlier RWAR acquisition and the new data were jointly analysed in order to improve on the earlier velocity model and extend its coverage landward and seaward. The resulting velocity model is characterized by an 8–9-km-thick sedimentary package immediately outboard of the Bonavista Platform, which thins toward the Orphan Knoll and beyond. The shallowest modelled sedimentary layer, interpreted as Paleocene and younger post-rift sediments, does not show significant thickness variations and velocities do not exceed 3.3 km s–1. The second modelled sedimentary layer with laterally variable velocities ranging from 2.3 to 5.3 km s–1, interpreted as Late Cretaceous post-rift sediments, is thickest over an interpreted failed rift. The deepest modelled sedimentary layer consists of laterally variable velocities that do not exceed 5.9 km s–1 and is interpreted as possibly Jurassic to Early Cretaceous syn-rift sediments. The crust beneath the Bonavista Platform is subdivided into an upper (5.4–5.9 km s–1), middle (5.9–6.4 km s–1) and lower crust (6.4–6.9 km s–1). The middle crust is modelled as disappearing beneath the seaward limit of the Bonavista Platform at an interpreted failed rift, only to re-appear 100 km further seaward beneath the central Orphan Basin and extend to the seaward limit of the Orphan Knoll, beyond which the crust can be modelled by just an upper (5.0–6.7 km s–1) and a lower (6.7–7.0 km s–1) crustal layer. Towards land, for the first 450 km of the model, velocities generally follow the globally averaged velocity trend for rifted continental crust, albeit with slightly elevated velocities suggestive of magmatic contributions. At the failed rift, within the continental domain, hyperextended crust is modelled, overlying a limited zone of serpentinized mantle. Seaward of Orphan Knoll, the interpretation for the velocity structure is less definitive but an 80-km-wide continent–ocean transition zone consisting of either transitional embryonic oceanic crust or thinned continental crust overlying serpentinized mantle is proposed. Upper mantle velocities as low as 7.7 km s–1 are modelled beneath the interpreted failed continental rift as well as beneath the continent–ocean transition zone, while the rest of the crustal model is underlain by typical mantle velocities of 8 km s–1. Analysis of extension and thinning factors based on the velocity model reveal that the failed rift experienced hyperextension and should have achieved full crustal embrittlement, consistent with localized mantle serpentinization.

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19

Marquis, Robert, and P. Stephen Kumarapeli. "An Early Cambrian deltaic–fluvial model for an Iapetan rift-arm drainage system, southeastern Quebec." Canadian Journal of Earth Sciences 30, no. 6 (1993): 1254–61. http://dx.doi.org/10.1139/e93-107.

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Based on the model that during the rifting stage beginning at ca. 590 Ma, the Ottawa Graben, an Iapetan failed arm, localized a large river that flowed into the nascent Iapetus, a search was made for the related fluvial and deltaic deposits. The search led to the identification of fluvial deposits as predicted by the model. Deltaic deposits were also identified despite complications brought about by deformation, metamorphism, and thrusting, although they probably belong to a late phase of delta buildup in the Early Cambrian. Older deltaic deposits of the river probably lie buried beneath a volcanic shield that built up at the proximal end of the graben ca. 554 Ma. The successful application of the model supports the paradigm of rift-arm – failed-arm rivers and their deltas as proposed by K. Burke and J.F. Dewey nearly two decades ago. Investigations based on this paradigm, in appropriate geological situations, may provide insights into problems related to continental rifting and breakup and provide information for the reconstruction of ancient rift–rift–rift (rrr) triple junctions and plate boundaries.

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20

Goodell, P. C., S. Gilder, and X. Fang. "A preliminary description of the Gan-Hang failed rift, southeastern china." Tectonophysics 197, no. 2-4 (1991): 245–55. http://dx.doi.org/10.1016/0040-1951(91)90044-s.

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21

Campbell, S. D. G., M. F. Howells, M. Smith, and A. J. Reedman. "A Caradoc Failed-Rift within the Ordovician Marginal Basin of Wales." Geological Magazine 125, no. 3 (1988): 257–66. http://dx.doi.org/10.1017/s0016756800010190.

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AbstractThe dolerite and basalt intrusions within the Lower Palaeozoic sequence of northwest Wales are largely restricted to the outcrop of Ordovician strata. Their distribution and close association with known volcano-tectonic structures were controlled by a tectonic framework of deep-seated fractures. In central and northern Snowdonia, volcanism during Caradoc times was related to the evolution of a fracture-controlled trough. An increase in the extensional stress across the trough with time is reflected in the progressive increase in basaltic magma movement during the volcanic cycle. The trough represents an attempted rift in the lithospheric plate, which failed to create an ocean basin and was subsequently aborted.

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22

Thomas, William A. "A Mechanism for Tectonic Inheritance at Transform Faults of the Iapetan Margin of Laurentia." Geoscience Canada 41, no. 3 (2014): 321. http://dx.doi.org/10.12789/geocanj.2014.41.048.

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Transform faults along the Iapetan rifted continental margin of Laurentia offset the continental rift and/or bound domains of oppositely dipping low-angle detachments. Rift-parallel and transform-parallel intracratonic fault systems extend into continental crust inboard from the rifted margin. Ages of synrift igneous rocks, ranging from 765 to 530 Ma, document non-systematic diachroneity of rifting along the Iapetan margin. Synrift sedimentary accumulations show abrupt variations in thickness across transform faults, and some concentrations of synrift igneous rocks are distributed along transform faults and transform-parallel intracratonic fault systems. The greatest thicknesses of Cambrian–Ordovician passive-margin shelf-carbonate deposits are along transform margins and in continental-margin basins along transform faults, as well as along transform-parallel intracratonic fault systems, indicating anomalously great post-rift thermal subsidence along transform faults. Along the Ordovician–Permian Appalachian-Ouachita orogenic belt, a diachronous array of synorogenic clastic wedges fills foreland basins, recording tectonic-load-driven flexural subsidence of the lithosphere. The greatest thicknesses of synorogenic clastic wedges of all ages are consistently in foreland basins along transform margins and inboard from intersections of transform faults with the rifted margin, indicating systematically weaker lithosphere along transform faults. The distinctive and pervasive properties and behaviour of the lithosphere along transform faults in successive tectonic settings suggest fundamental controls on tectonic inheritance at transform faults. Recent models for continental rifting incorporate ductile extension of the mantle lithosphere beneath brittle extension of the crust; the domain of ductile extension of the mantle lithosphere may reach significantly inboard from the rifted margin of the brittle crust, accounting for rift-parallel extensional faults in the crust inboard from the rifted margin. A transform offset of a rift in brittle crust requires a similar offset in ductile extension of the mantle lithosphere, leading to differential ductile flow on opposite sides of the transform and imparting a transform-parallel distributed-shear fabric. Transform-parallel distributed shear in the mantle lithosphere provides a mechanism for brittle transform-parallel fault systems in the continental crust. Studies of seismic anisotropy show fast directions parallel with transform faults, indicating systematic orientation of crystals through transform-parallel distributed shear in the mantle lithosphere.SOMMAIRELes failles transformantes le long de la marge continentale divergente japétienne de la Laurentie décalent le rift continental et/ou les domaines accrétés en des décollements à pendages opposés faibles. Des systèmes de failles intracratoniques parallèles au rift, et parallèles à la transformation, pénètrent vers l’intérieur de la croûte continentale à partir de la marge de rift. Les âges des roches ignées syn-rift, entre 765 Ma et 530 Ma, témoignent d’une activité de rifting diachronique non-systématique le long de la marge japétienne. Des empilements sédimentaires syn-rifts montrent des variations abruptes d’épaisseur d’une faille transformante à l’autre, et des concentrations de roches ignées syn-rifts se répartissent le long des systèmes de failles transformantes et de failles intracratoniques parallèles. Les accumulations les plus épaisses de carbonates de plateforme de marge continentale passive se trouvent le long des marges de cisaillement et dans les bassins de marge continentale le long de failles transformantes, de même qu’au long des systèmes de failles intracratoniques parallèles, évoquant une subsidence anormalement forte le long des failles transformantes. Le long de la bande orogénique ordovicienne-permienne Appalaches-Ouachita, une gamme diachronique de prismes clastiques synorogéniques remplit les bassins d’avant-pays, attestant d’une subsidence par flexure lithosphérique d’origine tectonique. Les plus grandes épaisseurs de prismes clastiques synorogéniques à tous les âges sont toujours situées dans les bassins d’avant-pays le long des marges transformantes, et vers l’intérieur, à partir des intersections des failles transformantes avec la marge de rift, indiquant une lithosphère systématiquement plus fragile le long des failles transformantes. Les propriétés particulières et le comportement généralisés de la lithosphère le long des failles transformantes dans les contextes tectoniques successifs sont la marque de contrôles fondamentaux sur l'héritage tectonique des failles transformantes. Les modèles récents de rifting continental comportent une extension ductile de la lithosphère mantellique sous l’extension cassante de la croûte; le domaine d'extension ductile de la lithosphère mantellique peut s’étendre significativement vers l’intérieur de la marge de divergence de la croûte cassante, d’où les failles d'extension parallèle au rift, à l’intérieur de la croûte de la marge de divergence. Un décalage de transformation de rift de la croûte comporte un décalage du même genre de l’extension ductile de la lithosphère mantellique, ce qui implique un différentiel de flux ductile sur les bords opposés de la transformation, d’où cette fabrique d’extension parallèle à la transformation. L’extension parallèle à la transformation de la lithosphère mantellique fournit un mécanisme qui explique les systèmes de failles transformantes parallèles dans la croûte continentale. Les études de l’anisotropie sismique montre les grandes vitesses de propagation parallèles aux failles de transformations, ce qui indique une orientation systématique des cristaux induite par une extension répartie selon les cassures transformantes dans la lithosphère mantellique.

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Reeves, C. V., F. M. Karanja, and I. N. MacLeod. "Geophysical evidence for a failed Jurassic rift and triple junction in Kenya." Earth and Planetary Science Letters 81, no. 2-3 (1987): 299–311. http://dx.doi.org/10.1016/0012-821x(87)90166-x.

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Ketner, Keith B., Raymond L. Ethington, John E. Repetski, Reuben J. Ross, and Charles G. Stone. "Comment and Reply on “Ouachita trough: Part of a Cambrian failed rift system”." Geology 14, no. 7 (1986): 627. http://dx.doi.org/10.1130/0091-7613(1986)14<627b:caroot>2.0.co;2.

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Lowe, Donald R. "Comment and Reply on “Ouachita trough: Part of a Cambrian failed rift system”." Geology 14, no. 7 (1986): 627. http://dx.doi.org/10.1130/0091-7613(1986)14<627c:caroot>2.0.co;2.

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Haddad, Yvonne Yazbeck, and Michael J. Balz. "The October Riots in France: A Failed Immigration Policy or the Empire Strikes Back?" International Migration 44, no. 2 (2006): 23–34. http://dx.doi.org/10.1111/j.1468-2435.2006.00362.x.

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Hill, Geoff. "THE ROLE OF THE PRE-RIFT STRUCTURE IN THE ARCHITECTURE OF THE DAMPIER BASIN AREA, NORTH WEST SHELF, AUSTRALIA." APPEA Journal 34, no. 1 (1994): 602. http://dx.doi.org/10.1071/aj93046.

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The Dampier Sub-basin shows many faults oblique to the basin axis. Previous explanations for this range from syn-rift transfer systems through to deep seated wrenching.Multiple rift episodes, with differing stress directions, occur in the area's history, each utilising the pre-existing fault patterns. As basement is difficult to interpret beneath thick sedimentary cover, the initial architecture is interpreted from the tectonic setting.The sub-basin lies adjacent to the Archean Pilbara Craton, a stable crustal block surrounded by ancient mobile belts. The East Africa rift system has also formed in a Craton margin setting. In East Africa earthquake data and detailed seismic interpretation show the rift utilises faults within the mobile belt systems.In the Dampier area, the three different extension vectors combined with the pre-rift fabric and the East Africa analogue, are used to build an alternate model for the basin genesis. Permo-Carboniferous extension sets up a rift system partitioned by the Precambrian fabric. Jurassic extension reactivates these faults but with oblique slip and dip slip movement caused by the new extension direction. This oblique slip causes complex branching arrays of new faults within the cover section. A third extension vector in the Cretaceous subsequently modifies the fabric. The Dampier Sub-basin is seen as a complex failed rift utilising a Precambrian tectonic fabric. The structural inheritance of the pre-rift fabric by each rift episode has affected the geometry of hydrocarbon-bearing structures of the sub-basin.

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Misra, Achyuta Ayan, Abhimanyu Maitra, Neeraj Sinha, Swagata Dey, and Shashirekha Mahapatra. "Syn- to post-rift fault evolution in a failed rift: a reflection seismic study in central Cambay Basin (Gujarat), India." International Journal of Earth Sciences 108, no. 4 (2019): 1293–316. http://dx.doi.org/10.1007/s00531-019-01706-w.

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DeBeauchamp, Jennifer L., Arian Moses, Victoria J. P. Noffsinger, et al. "Chp1-Tas3 Interaction Is Required To Recruit RITS to Fission Yeast Centromeres and for Maintenance of Centromeric Heterochromatin." Molecular and Cellular Biology 28, no. 7 (2008): 2154–66. http://dx.doi.org/10.1128/mcb.01637-07.

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ABSTRACT The maintenance of centromeric heterochromatin in fission yeast relies on the RNA interference-dependent complexes RITS (RNA-induced transcriptional silencing complex) and RDRC (RNA-directed RNA polymerase complex), which cooperate in a positive feedback loop to recruit high levels of histone H3 K9 methyltransferase activity to centromeres and to promote the assembly and maintenance of centromeric heterochromatin. However, it is unclear how these complexes are targeted to chromatin. RITS comprises Chp1, which binds K9-methylated histone H3; Ago1, which binds short interfering (siRNAs); the adaptor protein Tas3, which links Ago1 to Chp1; and centromeric siRNAs. We have generated mutants in RITS to determine the contribution of the two potential chromatin-targeting proteins Chp1 and Ago1 to the centromeric recruitment of RITS. Mutations in Tas3 that disrupt Ago1 binding are permissive for RITS recruitment and maintain centromeric heterochromatin, but the role of Tas3's interaction with Chp1 is unknown. Here, we define the Chp1 interaction domain of Tas3. A strain expressing a tas3 mutant that cannot bind Chp1 (Tas3Δ 10-24) failed to maintain centromeric heterochromatin, with a loss of centromeric siRNAs, a failure to recruit RITS and RDRC to centromeres, and high levels of chromosome loss. These findings suggest a pivotal role for Chp1 and its association with Tas3 for the recruitment of RITS, RDRC, and histone H3 K9 methyltransferase activity to centromeres.

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El-Kholei, Ahmed Osman. "Failed planning: lost opportunities and choices for the future." Open House International 45, no. 4 (2020): 387–406. http://dx.doi.org/10.1108/ohi-07-2020-0075.

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Purpose Social, spatial and environmental justice are inseparable, and key for sustainable urban development. The city is the cradle of innovation and production. Also, the city is the site of riots, where protesters demand their right to access services and resources. The purpose of this paper is to answer the question: Why do plans to resolve urban ills in developing countries fail to deliver and achieve social justice? Design/methodology/approach This paper investigates weaknesses, limitations and outcomes of planning processes in a developing country. The author used two qualitative research tools: document analysis augmented with informal interviews. The author uses Egypt as a case study in an attempt to answer this question. The author reviewed two types of documents: official reports that the Egyptian authorities produced and donor agencies prepared plus both published and unpublished research. Interviewees are those who participated in elaborating and executing urban plans and policies. Findings Achieving social, spatial and environmental justice is amongst the reasons for planning metropolitan areas and their regions. Unfortunately, rarely plans accomplish social, spatial or environmental justice. Institutional setup is the reason for failed urban planning – institutional failures lead to both policy and market failures, thus complicating urban problems. Originality/value Approved plans must have the power of legislation, and planners need to reclaim their authority and autonomy, which requires regulating the profession. Planning education must be at the graduate level and available to other disciplines, such as economics, public administration, law and the like. Planners must acquire the following competencies: technical competencies for analytical actions; hermeneutic competencies for communicative actions; and critical competencies to observe professional ethics. They must emancipate themselves from their bias to enlighten and empower their constituents.

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Shemang, E. M., C. O. Ajayi, and W. R. Jacoby. "A magmatic failed rift beneath the Gongola arm of the upper Benue trough, Nigeria?" Journal of Geodynamics 32, no. 3 (2001): 355–71. http://dx.doi.org/10.1016/s0264-3707(01)00034-5.

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Acharyya, Subhrangsu K., and Puspendu Saha. "Himalayan Paleogene Foreland Basin, its collision induced early volcanic history and failed rift initiation." Journal of Asian Earth Sciences 162 (August 2018): 3–12. http://dx.doi.org/10.1016/j.jseaes.2018.04.031.

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Matsubara, Makoto, Hiroshi Sato, Kenji Uehira, Masashi Mochizuki, and Toshihiko Kanazawa. "Three-Dimensional Seismic Velocity Structure Beneath Japanese Islands and Surroundings Based on NIED Seismic Networks Using both Inland and Offshore Events." Journal of Disaster Research 12, no. 5 (2017): 844–57. http://dx.doi.org/10.20965/jdr.2017.p0844.

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Tomographic analysis of the seismic velocity structure beneath oceans has always been difficult because offshore events determined by onshore seismic networks have large uncertainties in depth. In order to use reliable event locations for our computations, we have developed a method to use the hypocentral depths determined by the NIED F-net with moment tensor solutions using long-period (20-50 s) waves from offshore events away from onshore seismic networks. We applied seismic tomographic method to events occurring between the years 2000 and 2015 to generate a tomographic image of the Japanese Islands and the surrounding using travel time data picked by the NIED Hi-net, hypocenteral information for onshore earthquakes from the Hi-net, and hypocenter information for offshore events from the F-net. The seismic velocity structure at depths of 30-50 km beneath the Pacific Ocean off the east coast of northeastern Japan and onshore Japan was clearly imaged using both onshore and offshore event date. The boundary between high and low P-wave velocities (Vp) is clearly seen at the Median Tectonic Line beneath southwestern Japan at depths of 10 and 20 km. We discuss how the high-Vp lower crust and low-Vp upper crust beneath central Japan and towards the Sea of Japan are responsible for the failed rift structures formed during the opening of the Sea of Japan. Due to consequent shortening, the crustal deformation has been concentrated along the failed rift zone. Resolution of shallow structures beneath the ocean is investigated using S-net data, confirming the possibility of imaging depths of 5-20 km. In future studies, application of S-net data will be useful in evaluating whether the failed rift structure, formed during the late Cretaceous to early Tertiary, continues towards the shallow regions beneath the Pacific Ocean.

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Oliver, Pamela. "Repression and Crime Control: Why Social Movement Scholars Should Pay Attention to Mass Incarceration as a Form of Repression." Mobilization: An International Quarterly 13, no. 1 (2008): 1–24. http://dx.doi.org/10.17813/maiq.13.1.v264hx580h486641.

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The disciplinary insurgency that created the academic field of social movement studies distinguished dissent from crime. This dichotomy has led the field to ignore the relation between the repression of dissent and the control of "ordinary" crime. There was massive repression in the wake of the Black riots of the 1960s that did not abate when the riots abated. The acceleration of the mass incarceration of African Americans in the United States after 1980 suggests the possibility that crime control and especially the drug war have had the consequence of repressing dissent among the poor. Social movement scholars have failed to recognize these trends as repression because of the theoretical turn that built too strong a conceptual wall between crime and dissent. Revisiting this dichotomy is essential for understanding repression today.

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Hill, K. A., D. M. Finlayson, K. C. Hill, and G. T. Cooper. "MESOZOIC TECTONICS OF THE OTWAY BASIN REGION: THE LEGACY OF GONDWANA AND THE ACTVE PACIFIC MARGIN—A REVIEW AND ONGOING RESEARCH." APPEA Journal 35, no. 1 (1995): 467. http://dx.doi.org/10.1071/aj94030.

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Mesozoic extension along Australia's southern margin and the evolution and architecture of the Otway Basin were probably controlled by three factors: 1) changes in global plate movements driven by mantle processes; 2) the structural grain of Palaeozoic basement; and, 3) changes in subduction along Gondwana's Pacific margin. Major plate realignments controlled the Jurassic onset of rifting, the mid-Cretaceous break-up and the Eocene onset of rapid spreading in the Southern Ocean.The initial southern margin rift site was influenced by the northern limit of Pacific margin (extensional) Jurassic dolerites and the rifting may have terminated dolerite emplacement. Changed conditions of Pacific margin subduction (e.g. ridge subduction) in the Aptian may have placed the Australia-Antarctic plates into minor compression, abating Neocomian southern margin rifting. It also produced vast amounts of volcanolithic sediment from the Pacific margin arc that was funnelled down the rift graben, causing additional regional subsidence due to loading. Albian orogenic collapse of the Pacific margin, related to collision with the Phoenix Plate, influenced mid-Cretaceous breakup propagating south of Tasmania and into the Tasman Sea.Major offsets of the spreading axis during breakup, at the Tasman and Spencer Fracture zones, were most likely controlled by the location of Palaeozoic terrane boundaries. The Tasman Fracture System was reactivated during break-up, with considerable uplift and denudation of the Bass failed rift to the east, which controlled Otway Basin facies distribution. Palaeozoic structures also had a significant effect in determining the half graben orientations within a general N-S extensional regime during early Cretaceous rifting. The late Cretaceous second stage of rifting, seaward of the Tartwaup, Timboon and Sorell fault zones, left a stable failed rift margin to the north, but the attenuated lithosphere of the Otway-Sorell microplate to the south records repeated extension that led to continental separation and may be part of an Antarctic upper plate.

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White, J. D. L., and M. K. McClintock. "Immense vent complex marks flood-basalt eruption in a wet, failed rift: Coombs Hills, Antarctica." Geology 29, no. 10 (2001): 935. http://dx.doi.org/10.1130/0091-7613(2001)029<0935:ivcmfb>2.0.co;2.

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Jokat, Wilfried, and Ulrich Herter. "Jurassic failed rift system below the Filchner-Ronne-Shelf, Antarctica: New evidence from geophysical data." Tectonophysics 688 (October 2016): 65–83. http://dx.doi.org/10.1016/j.tecto.2016.09.018.

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Johnston, Arch C., and Kaye M. Shedlock. "Overview of Research in The New Madrid Seismic Zone." Seismological Research Letters 63, no. 3 (1992): 193–208. http://dx.doi.org/10.1785/gssrl.63.3.193.

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Abstract We review the development of understanding of the seismicity and tectonic structure of the New Madrid seismic zone and the upper Mississippi embayment. The broad framework of a failed intracontinental rift with reactivated seismogenic faults was not established until the mid-1970s. By the early 1990s a much more detailed knowledge of the rift and the current seismicity has been gained but fundamental questions remain. The 25 papers of this Special Issue of Seismological Research Letters convey the location of the most recent research front in such diverse fields as seismology, paleoseismology, seismic and potential-field investigation of rift structure, neotectonic deformation, and seismic hazard estimation and response. The new information content of these papers, considered ensemble, is enormous and highlights the tremendous progress made since the 1970s. These current studies, in turn, sharpen the focus on remaining outstanding problems of seismogenesis in the New Madrid seismic zone. We close with a discussion of what we believe will be the important foci of research in the 1990s.

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Oterdoom, W. Heiko, Mike A. Worthing, and Mark Partington. "Petrological and Tectonostratigraphic Evidence for a Mid Ordovician Rift Pulse on the Arabian Peninsula." GeoArabia 4, no. 4 (1999): 467–500. http://dx.doi.org/10.2113/geoarabia0404467.

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ABSTRACT During late Early Ordovician times an increase in the rate of subsidence in the Ghaba Salt Basin and western South Oman Salt Basin is suggested by the thick sequence of continental clastics of the Ghudun Formation. After a phase of rift-shoulder uplift and erosion, related to a renewed pulse of extension which may have initiated diapiric growth of salt structures in the Ghaba Salt Basin, sedimentation resumed again in the Mid Ordovician. During this period, the center of deposition shifted to the Saih Hatat area in North Oman. This paper documents seismic and well data, field investigations and petrological study of potassic mafic rocks from the Huqf area which were intruded in the eastern side of the Ghaba Salt Basin. A Mid Ordovician age of 461 ± 2.4 million years has been established for these rocks by the Argon-Argon step heating method. Analogy with the petrology and setting of similar potassic mafic rocks from the Rio Grande Rift in the western United States of America suggests that they were intruded into the shoulder of an intra-continental rift. The data provide the first clear evidence of a pulse of rift-shoulder uplift in the Huqf area during the Mid Ordovician. The 3-kilometer-thick Mid to Late Ordovician clastic sediments of the Amdeh Formation in North Oman, together with the occurrence of abnormally thick sedimentary sequences and volcanics in the Tabas Graben in Iran, are consistent with a period of break-up of eastern Gondwana. Together, the Ghaba-Saih Hatat and Tabas Basins are considered to be part of a failed rift arm. These observations further improve our regional knowledge of the Early to Late Ordovician tectonic setting of Oman and will assist in unlocking the hydrocarbon potential of classical rift-related structures consisting of early-rift Early Ordovician sand-prone reservoirs sealed by syn-rift Mid to Late Ordovician marine shales.

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Dickin, A. P., and R. H. McNutt. "The Central Metasedimentary Belt (Grenville Province) as a failed back-arc rift zone: Nd isotope evidence." Earth and Planetary Science Letters 259, no. 1-2 (2007): 97–106. http://dx.doi.org/10.1016/j.epsl.2007.04.031.

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Bosworth, William, and Gábor Tari. "Hydrocarbon accumulation in basins with multiple phases of extension and inversion: examples from the Western Desert (Egypt) and the western Black Sea." Solid Earth 12, no. 1 (2021): 59–77. http://dx.doi.org/10.5194/se-12-59-2021.

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Abstract. Folds associated with inverted extensional faults are important exploration targets in many basins across our planet. A common cause for failure to trap hydrocarbons in inversion structures is crestal breaching or erosion of top seal. The likelihood of failure increases as the intensity of inversion grows. Inversion also decreases the amount of overburden, which can adversely affect maturation of source rocks within the underlying syn-extensional stratigraphic section. However, many rift basins are multi-phase in origin, and in some cases the various syn-rift and post-rift events are separated by multiple phases of shortening. When an inversion event is followed by a later phase of extension and subsidence, new top seals can be deposited and hydrocarbon maturation enhanced or reinitiated. These more complex rift histories can result in intra-basinal folds that have higher chances of success than single-phase inversion-related targets. In other basins, repeated inversion events can occur without significant intervening extension. This can also produce more complicated hydrocarbon maturation histories and trap geometries. Multiple phases of rifting and inversion affected numerous basins in North Africa and the Black Sea region and produced some structures that are now prolific hydrocarbon producing fields and others that failed. Understanding a basin's sequence of extensional and contractional events and the resulting complex interactions is essential to formulating successful exploration strategies in these settings.

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McCormick, Kelli A., Kevin R. Chamberlain, and Colin J. Paterson. "U–Pb baddeleyite crystallization age for a Corson diabase intrusion: possible Midcontinent Rift magmatism in eastern South Dakota." Canadian Journal of Earth Sciences 55, no. 2 (2018): 111–17. http://dx.doi.org/10.1139/cjes-2017-0140.

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The largely buried basement of the northern Great Plains includes suture zones and terrane boundaries that represent a significant part of the growth of Laurentia in the Proterozoic. Basement exposures in this region east of the Black Hills are rare. In southeastern South Dakota, southwestern Minnesota, northeastern Nebraska, and northwestern Iowa, small outcrops of the Proterozoic Sioux Quartzite occur. In southeastern South Dakota, Corson diabase sills or dykes have intruded the quartzite. U–Pb ID–TIMS baddeleyite data from a Corson diabase sample yield an upper intercept date of 1149.4 ± 7.3 Ma, suggesting the diabase is related temporally to the Midcontinent Rift (MCR). The similarity in age of this diabase to the Inspiration sill, Pigeon River, Kipling, and Abitibi dykes suggests that early Midcontinent Rift development was not localized within the Nipigon Embayment, but extended along a roughly east–northeast zone from the Abitibi dykes to the Corson diabase. The presence of the Corson intrusions 250 km west of the MCR is hypothesized to represent a failed rift arm within the Superior craton. The greater strength of the Superior craton relative to lithosphere south of the Spirit Lake tectonic zone resulted in a shift of the southwestern rift arm in southern Minnesota along the Belle Plaine fault southeastward to the Iowa border. Alternatively, the apparent northeast trend of known occurrences of the Corson diabase is also consistent with a mantle plume centre explanation for early Midcontinent rifting.

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Sreehari, Lakshmanan, Tsuyoshi Toyoshima, Madhusoodhan Satish-Kumar, Toshiro Takahashi, and Hayato Ueda. "Structural and geochemical evidence for a failed rift crustal evolution model in Western Dharwar Craton, South India." Lithos 388-389 (May 2021): 106020. http://dx.doi.org/10.1016/j.lithos.2021.106020.

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Swanson-Hysell, Nicholas L., Jahandar Ramezani, Luke M. Fairchild, and Ian R. Rose. "Failed rifting and fast drifting: Midcontinent Rift development, Laurentia’s rapid motion and the driver of Grenvillian orogenesis." GSA Bulletin 131, no. 5-6 (2019): 913–40. http://dx.doi.org/10.1130/b31944.1.

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45

Dannowski, Anke, Heidrun Kopp, Ingo Grevemeyer, et al. "Seismic evidence for failed rifting in the Ligurian Basin, Western Alpine domain." Solid Earth 11, no. 3 (2020): 873–87. http://dx.doi.org/10.5194/se-11-873-2020.

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Abstract. The Ligurian Basin is located in the Mediterranean Sea to the north-west of Corsica at the transition from the Western Alpine orogen to the Apennine system and was generated by the south-eastward trench retreat of the Apennines–Calabrian subduction zone. Late-Oligocene-to-Miocene rifting caused continental extension and subsidence, leading to the opening of the basin. Yet it remains unclear if rifting caused continental break-up and seafloor spreading. To reveal its lithospheric architecture, we acquired a 130 km long seismic refraction and wide-angle reflection profile in the Ligurian Basin. The seismic line was recorded in the framework of SPP2017 4D-MB, a Priority Programme of the German Research Foundation (DFG) and the German component of the European AlpArray initiative, and trends in a NE–SW direction at the centre of the Ligurian Basin, roughly parallel to the French coastline. The seismic data were recorded on the newly developed GEOLOG recorder, designed at GEOMAR, and are dominated by sedimentary refractions and show mantle Pn arrivals at offsets of up to 70 km and a very prominent wide-angle Mohorovičić discontinuity (Moho) reflection. The main features share several characteristics (e.g. offset range, continuity) generally associated with continental settings rather than documenting oceanic crust emplaced by seafloor spreading. Seismic tomography results are complemented by gravity data and yield a ∼ 6–8 km thick sedimentary cover and the seismic Moho at 11–13 km depth below the sea surface. Our study reveals that the oceanic domain does not extend as far north as previously assumed. Whether Oligocene–Miocene extension led to extremely thinned continental crust or exhumed subcontinental mantle remains unclear. A low grade of mantle serpentinisation indicates a high rate of syn-rift sedimentation. However, rifting failed before oceanic spreading was initiated, and continental crust thickens towards the NE within the northern Ligurian Basin.

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Brewer, T. S., D. Rex, P. G. Guise, and C. J. Hawkesworth. "Geochronology of Mesozoic tholeiitic magmatism in Antarctica: implications for the development of the failed Weddell Sea rift system." Geological Society, London, Special Publications 108, no. 1 (1996): 45–61. http://dx.doi.org/10.1144/gsl.sp.1996.108.01.04.

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Baher, Shirley, Clifford Thurber, Kyle Roberts, and Charlotte Rowe. "Relocation of seismicity preceding the 1984 eruption of Mauna Loa Volcano, Hawaii: Delineation of a possible failed rift." Journal of Volcanology and Geothermal Research 128, no. 4 (2003): 327–39. http://dx.doi.org/10.1016/s0377-0273(03)00199-9.

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48

Oesterlen, P. M., and T. G. Blenkinsop. "Extension directions and strain near the failed triple junction of the Zambezi and Luangwa Rift zones, southern Africa." Journal of African Earth Sciences 18, no. 2 (1994): 175–80. http://dx.doi.org/10.1016/0899-5362(94)90029-9.

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Shoko, D. S. M. "Extension directions and strain near the failed triple junction of the Zambezi and Luangwa Rift zones, southern Africa." Journal of African Earth Sciences 22, no. 4 (1996): 617–20. http://dx.doi.org/10.1016/0899-5362(96)00040-1.

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Rahman, Rofi Aulia, and Shu-Mei Tang. "Fake News and Internet Shutdowns in Indonesia: Symptoms of Failure to Uphold Democracy." Constitutional Review 8, no. 1 (2022): 151. http://dx.doi.org/10.31078/consrev816.

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The Indonesian government limited or shut down internet access during separate riots in Jakarta and Papua in 2019. The justification for blocking the internet and disabling certain features of social media platforms was to quell the unrest by ceasing the spread of fake news. Nevertheless, the government did not declare a state of emergency in response to either situation, triggering debate on whether the internet restrictions had any strong constitutional basis or if they were out of proportion and unconstitutional. This study evaluates the government’s policy on internet shutdowns to reduce the spread of fake news amid riots, and explicates when the state of emergency “feature” might be activated. The research method of this article is a doctrinal legal approach, which critically examines whether the government policy was excessive, and to what extent a state of emergency can be implemented by minimum standard requirements. The result of this study shows the riots in Jakarta and Papua ought not be categorized as national threats; hence, the internet shutdown was out of proportion. Fake news is part of the price we pay for a free society; thus the article argues that an internet shutdown is not a proper way to combat fakenews. Furthermore, the government has failed to fulfill the minimum standards to justify the internet shutdowns. Access to the internet is a new face of democratic pillars, so blocking internet access without any sufficient legal instruments and correct constitutional interpretation might indicate symptoms of a failure to uphold democracy.

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