transfer zones
Recently Published Documents


TOTAL DOCUMENTS

87
(FIVE YEARS 20)

H-INDEX

22
(FIVE YEARS 1)

2021 ◽  
pp. 1-19
Author(s):  
Paritosh Bhatnagar ◽  
Pierre Karam ◽  
Sumit Verma

We analyzed a synthetic transfer zone and its associated fault planes and relay ramp in Penobscot, a potential offshore field in the Scotian Basin. Transfer zones are structural areas where one fault dies out and another fault begins, forming a relay ramp in the middle. They can be categorized as divergent, convergent, and synthetic transfer zones depending on the relative location and dipping directions of the faults. These zones not only play an important role in fluid migration but also help interpreters delineate secondary features such as fractures, splay shears, and Riedel faults. Commonly those faults would branch into smaller splays and the relay ramp can get “breached” with connecting faults with the increase of slip. The study area in the Scotian basin is characterized by two major listric normal faults dipping in the same direction giving rise to a synthetic transfer zone. These faults are clearly visible on seismic attributes, including curvature and coherence slices extracted along the top of the Cretaceous Petrel Formation. However, when analyzing the seismic attributes along the overlying Wyandot Formation’s top, we observe channel-like features, which run parallel as well as at an angle to these faults. However, when we performed further analysis using seismic amplitude’s vertical slices, interpreted horizons, and seismic attributes, we found that these features are not channels. We divided the features into two types, the first is parallel to the main faults and can be associated with the grabens formed by synthetic and antithetic secondary faults (NE-SW). The second type is related to the polygonal faulting associated with differential compaction and gravitational loading of the Wyandot Chalk Formation. Apart from the two lineations, there are NNE-SSW oriented lineations which are an impression of basement faulting, and NNW-SSE oriented lineations representing acquisition footprint.


2021 ◽  
Vol 11 (15) ◽  
pp. 7138
Author(s):  
Sergio Nesmachnow ◽  
Claudio Risso

This article addresses timetable synchronization in public transportation, an important problem in modern smart cities, in order to guarantee a proper quality of service to citizens. Two variants of the bus timetabling synchronization problem considering extended transfer zones are studied: optimizing offsets and optimizing offsets and headways for each line. An exact mixed integer programming and an evolutionary algorithm are developed to solve both problem variants. The algorithms are evaluated on 45 instances of a real case study, the intelligent transportation system of Montevideo, Uruguay. Experimental results reported significant improvements over the current timetable implemented by the city administration. The number of successful synchronizations improved up to 66.6% and 179.9% for the first and second problem variant, respectively. The average waiting times for transfers improved, especially in tight problem instances (up to 57.8% and 158.3% for the first and second problem variant, respectively). The proposed planning methods are useful to help decision makers to configure public transportation systems.


2021 ◽  
Vol 9 ◽  
Author(s):  
Jean-Charles Schaegis ◽  
Valentin Rime ◽  
Tesfaye Kidane ◽  
Jon Mosar ◽  
Ermias Filfilu Gebru ◽  
...  

Lake Afdera is a hypersaline endorheic lake situated at 112 m below sea-level in the Danakil Depression. The Danakil Depression is located in the northern part of the Ethiopian Afar and features an advanced stage of continental rifting. The remoteness and inhospitable environment explain the limited scientific research and knowledge about this lake. Bathymetric data were acquired during 2 weeks expeditions in January/February 2016 and 2017 using an easily deployable echosounder system mounted on an inflatable motorized boat. This study presents the first complete bathymetric map of the lake Afdera. Bathymetric results show that the lake has an average depth of 20.9 m and a total volume of 2.4 km3. The maximum measured depth is 80 m, making Lake Afdera the deepest known lake in Afar and the lowest elevation of the Danakil Depression. Comparison with historical reports shows that the lake level did not fluctuate significantly during the last 50 years. Two distinct tectonic basins to the north and the south are recognized. Faults of different orientations control the morphology of the northern basin. In contrast, the southern basin is affected by volcano-tectonic processes, unveiling a large submerged caldera. Comparison between the orientation of faults throughout the lake with the regional fault pattern indicates that the lake is part of two transfer zones: the major Alayta–Afdera Transfer Zone and the smaller Erta Ale–Tat’Ali Transfer Zone. The interaction between these Transfer Zones and the rift axis forms the equivalent of a developing nodal basin which explains the lake’s position as the deepest point of the depression. This study provides evidence for the development of an incipient transform fault on the floor of the Afar depression.


2021 ◽  
Author(s):  
Jie Yuan ◽  
Armin Safari ◽  
Paul Lugo ◽  
Laura Alvarez ◽  
Ronald Hofmann

Ecosphere ◽  
2021 ◽  
Vol 12 (5) ◽  
Author(s):  
L. Marinoni ◽  
M. Parra Quijano ◽  
J. M. Zabala ◽  
J. F. Pensiero ◽  
J. M. Iriondo

2021 ◽  
pp. 1-73
Author(s):  
Pierre Karam ◽  
Shankar Mitra ◽  
Kurt Marfurt ◽  
Brett M. Carpenter

Synthetic transfer zones develop between fault segments which dip in the same direction, with relay ramps connecting the fault blocks separated by the different fault segments. The characteristics of the transfer zones are controlled by the lithology, deformation conditions, and strain magnitude. The Parihaka fault is a NE-SW trending set of three major en-echelon faults connected by relay ramps in the Taranaki Basin, New Zealand. The structure in the basin is defined by extension during two episodes of deformation between the late Cretaceous and Paleocene and between the Late Miocene and recent. To better understand the evolution of a synthetic transfer zone, we study the geometry and secondary faulting between the individual fault segments in the Parihaka fault system using structural interpretation of 3D seismic data and seismic attributes. This interpretation allows for a unique application of seismic attributes to better study transfer zones. Seismic attributes, including coherence, dip, and curvature are effective tools to understand the detailed geometry and variation in displacement on the individual faults, the nature of secondary faulting along the transfer zones, and the relationship between the faults and drape folds. Seismic characterization of the fault system of Miocene to Pliocene age horizons highlights variations in the degree of faulting, deformation, and growth mechanism associated with different stages of transfer zone development. Coherence, dip, and curvature attributes show a direct correlation with structural parameters such as deformation, folding, and breaching of relay ramps.. All three attributes enhance the visualization of the major and associated secondary faults and better constrain their tectonic history. The observed correlation between seismic attributes and structural characteristics of transfer zones can significantly improve structural interpretation and exploration workflow.


Author(s):  
Laurent JOLIVET ◽  
Armel MENANT ◽  
Vincent ROCHE ◽  
Laetitia LE POURHIET ◽  
Agnès MAILLARD ◽  
...  

Slab tearing induces localized deformations in the overriding plates of subduction zones and transfer zones accommodating differential retreat. Because the space available for retreating slabs is limited in the Mediterranean realm, slab tearing during retreat has been a major ingredient of the evolution of this region since the end of the Eocene. The association of detailed seismic tomographic models and extensive field observations makes the Mediterranean an ideal natural laboratory to study these transfer zones. We review in this paper the various structures accommodating differential retreat in the crust from the Alboran Sea to the Aegean-Anatolian region and discuss them with the help of 3D numerical models. Simple, archetypal, crustal-scale strike-slip faults are in fact rare in these contexts above slab tears. Transfer zones are in general instead wide deformation zones, from several tens to several hundred kilometers. A partitioning of deformation is observed between the upper and the lower crust with low-angle extensional shear zones at depth and complex association of transtensional basins at the surface. In the Western Mediterranean, between the Gulf of Lion and the Valencia basin, transtensional strike-slip faults are associated with syn-rift basins and lower crustal domes elongated in the direction of retreat (a-type domes), associated with massive magmatic intrusions in the lower crust and volcanism at the surface. On the northern side of the Alboran Sea, wide E-W trending strike-slip zones show partitioned thrusting and strike-slip faulting in the external zones of the Betics, and E-W trending metamorphic core complexes in the internal zones, parallel to the main retreat direction. On the opposite, the southern margin of the Alboran Sea shows short en-échelon strike-slip faults. In the Aegean-Anatolian region two main tear faults with different degrees of maturity are observed. Western Anatolia (Menderes Massif) and the Eastern Aegean Sea evolved above a major left-lateral tear in the Hellenic slab. In the crust, the differential retreat was accommodated mostly by low-angle shear zones with a constant direction of stretching and the formation of a-type high-temperature domes. On the opposite side of the Aegean region, the Corinth and Volos Rift as well as the Kephalonia fault offshore, accommodate the formation of a dextral tear fault. We discuss the rare occurrence of pure strike-slip faults in these contexts and propose that the high heat flow above the retreating slabs and more especially above slab tears favors a ductile behavior with distributed deformation of the crust and the formation of low-angle shear zones and high-temperature domes. While retreat proceeds, aided by tears, true strike-slip fault system may localize and propagate toward the retreating trench, ultimately leading to the formation of new plate boundary, as shown by the example of the North Anatolian Fault.


2021 ◽  
Author(s):  
Folarin Kolawole ◽  
Max Firkins ◽  
Thuwaiba Al Wahaibi ◽  
Estella Atekwana ◽  
Michael Soreghan

2021 ◽  
Vol 19 (5) ◽  
pp. 4129-4149
Author(s):  
D. CEVALLOS ◽  
K. SZITAR ◽  
M. HALASSY ◽  
A. KÖVENDI-JAKÓ ◽  
K. TÖRÖK

2020 ◽  
pp. jgs2020-199
Author(s):  
J. D. Wiest ◽  
J. Jacobs ◽  
H. Fossen ◽  
M. Ganerød ◽  
P. T. Osmundsen

The (ultra)high-pressure Western Gneiss Region (WGR) of the Norwegian Caledonides represents an archetypical orogenic infrastructure of a continent-continent collision zone. To test established exhumation models, we synthesize the geochronology and structures of major basement windows and provide new ages from poorly dated areas. Migmatite U-Pb zircon samples date melt crystallization at ∼405 Ma in the Øygarden Complex, expanding the spatial extent of Devonian migmatization. Micas from shear zones in the Øygarden and Gulen domes yield 40Ar/39Ar ages mostly between 405 and 398 Ma, recording exhumation of metamorphic core complexes. On a larger scale, the youngest ages of various geochronometers in different segments of the WGR show abrupt breaks (10 – 30 Myrs) across low-angle detachments and sinistral transfer zones, which also correspond to metamorphic and structural discontinuities. We explain segmentation of the orogenic infrastructure by partitioned post-orogenic transtension due to lateral and vertical rheological contrasts in the orogenic edifice (strong cratonic foreland and orogenic wedge vs. soft infrastructure). Differential crustal stretching dragged out deep levels of the orogenic crust below low-angle detachments and became progressively dominated by sinistral transfer zones. Collapse obliterated the syn-collisional structure of the orogenic root and resulted in the diachronous exhumation of distinct infrastructure segments. Supplementary material:https://doi.org/10.6084/m9.figshare.c.5241710


Sign in / Sign up

Export Citation Format

Share Document