African Plate Research Articles

Geochemical characteristics of the lava domes in Yatagan village and Sağlik town, from Erenlerdagi (Konya, Central Turkey) volcanites

Extensive Late Miocene to Pliocene Erenlerdagi volcanism produced lava domes, nuee ardentes and ignimbrite deposits in west and southwest of the Konya. The domes may contain various enclaves, which range in size from a few cm to a few meters, and in shape cornered to spherical. The volcanic rocks are made up of plagioclase (15-45%), brown amphibole (3-15%), brown biotite (5-10 %), quartz (0-5%), sanidine (0-5%), clinopyroxene (0-5 %), epidote (0-8%), opaque iron ore (3-20%), and accessory acicular apatite and zircon in a holocrystalline porphyric texture. Geochemical data shows that all samples are high-K calc-alkaline, mostly metaluminous, and rhyodacite to andesite in composition. They are characterized by an enrichment in Large Ion lithophile Elements (e.g. Cs, K), and a depletion in High Field Strength Elements (e.g. Ti, Y). In Harker variation diagrams, SiO2 increases with increasing K2O, Na2O, Rb, Th, U, Nb, Zr contents; and decreasing TiO2, FeOt, MgO, CaO contents, suggesting fractional crystallisation of hornblende (± pyroxene, olivine) and titanite. The REE pattern of the samples shows an enrichment in Light Rare Earth Elements, and a depletion in Heavy Rare Earth Elements, resultant with high ((La/Lu)N= 8.2-18.0) ratios. Existence of slight Eu anomaly (Eu/Eu*: 0.66-0.80 ) may suggest plagioclase fractionation in the samples. Based on field, mineralogical and geochemical data, it has been suggested that the Erenlerdagi volcanics could have formed by chemical mixing of felsic and mafic magmas possibly coupled with fractional crystallisation of hornblende (± pyroxene, olivine), plagioclase and titanite, in relation with the subduction of the African plate underneath the Anatolian plate during Miocene.

RETRACTED: Rift-related active fault-system and a direction of maximum horizontal stress in the Cairo-Suez district, northeastern Egypt: A new approach from EMR-Technique and Cerescope data

An active fault system has been detected along the Cairo-Suez district in northeastern Egypt, applying the EMR-Technique using Cerescope. The E-W (old Mediterranean) and NW-SE (Red Sea-Gulf of Suez) fault-trends are estimated to have ongoing activity. Horizontal EMR-measurements indicate a NW to NNW orientation as a maximum horizontal stress direction (σ1), whereas an E-W orientation to has a secondary tendency. A simplified stress map for the Cairo-Suez district is constructed from the horizontal stress data measured at about 20 locations within the district. The mapped stresses will contribute to the stress data of the Cairo-Suez region on the world stress map (WSM). The present study results indicate rejuvenation of the inherited Mesozoic E-W oriented and Oligocene-Miocene rift-related NW-SE oriented faults. The transfer of rift-related deformation from Red Sea-Gulf of Suez region, which is currently undergoing an extensional stress regime in NE to NNE direction, would explain a seismotectonic activity of the Cairo-Suez district. These results are consistent with a present day NNW oriented compressional stresses attributed to a convergence between the African and Eurasian plates.

Landscape evolution and landform inheritance in tectonically active regions: The case of the Southwestern Peloponnese, Greece

The Peloponnese in southwestern Greece fronts the Hellenic Arc at the boundary between the European and African plates. The relief is developed across deeply eroded nappes and folds that represent ...

Use of the ESI-2007 scale to evaluate the 2003 Boumerdès earthquake (North Algeria)

<p>In this study, we applied the environmental seismic intensity (ESI-2007) scale to a major recent Algerian earthquake. The ESI-2007 scale is an effective tool to assess the seismic hazard and has been applied to onshore earthquakes. Here we applied the scale to a recent earthquake (Mw 6.8, 2003) that took place offshore in the province of Boumerdès in the north of Algeria along the boundary between African and Eurasian plates. The main shock was associated to an unknown submarine structure. No surface ruptures were observed on the onshore domain, but many earthquake environmental effects (EEEs) were reported during several field investigations. In addition to onshore ground effects, this event triggered turbidity currents responsible for 29 submarine cable breaks. Mapping and describing coseismic ground effects allowed us to distinguish primary and secondary effects like coastal uplifts, liquefaction phenomena, tsunami waves, turbidity currents, cracks, rock falls, slope movements and hydrological anomalies. Considering the total area affected and the distribution of ground effects, we suggest intensity X that appears in agreement with intensity calculated in previous study with the EMS-98 scale. Thus, this method is validated even in the case of a coastal earthquake, and could be applied in the future to Algerian historical earthquakes that have affected scarcely inhabited zones but where EEEs were listed and located.</p>

The movement of the Arabian plate and its impact on the formation of superficial manifestations


 
 
 
 
 
 
 
 
 
 Arabian plate movement and its impact on the composition of the surface manifestations The surface of the earthis covered with several major and minor plates.These plates are in a continuousmovement of collision and .spacing.The Arabian plate is part of this process The Arabian plate is generallylocated in the North-East of the earth.More specifically,it is located between Eurasian and Anatolian plates from the north, the Indo-Australian plate from the East,the African and Indo-Australian plate from the south, and both the Red Sea .and the Mediterranean Seaform its western border Its extremepoints from the North to the South are about (341849 km) far from each other and from the East to the West are about (8162954km) .)far.Its total area is (1،222،222 km1 The Arabian Plate is in a continuous movement of an estimated (8-3cm) per yearfrom millions of years ago to the present time.The direction of its movement is North-East. The result of its collisionwith the Eurasian and Indo-Australian plate led to the formation of the Zagros mountain from the east and Taurus series from the north.This is accompanied by it spacing with the African Plate and the formation of the Red Sea which causes the formation of the volcanically active areas around the Red Sea, especially at the Strait of BabAL Mandeb and the Gulf of Aden. Finally,the movement of the Arabian plate is the main factor considered in the formation of surface and geomorphological manifestations of the area such as the composition of mountain series, volcanic peaks and the expansion of the Red Sea... etc.
 
 
 
 
 
 
 
 
 

Post-Variscan evolution of the Anti-Atlas belt of Morocco constrained from low-temperature geochronology

The Anti-Atlas belt of Morocco extends ENE–WSW, over more than 600 km, from the Atlantic margin in the west to the interior of the African plate in the east. It exhibits Precambrian rocks outcropping as basement inliers and surrounded by marine Ediacaran–Cambrian sequences around the axis of the mountain range. The belt, which has for a long time been interpreted as of Variscan age, is now revealed to have experienced major vertical movements through Mesozoic and Cenozoic times. Thereby, the Anti-Atlas domain appears to be affected by two episodes of exhumation separated by an episode of subsidence. The initial episode occurred in the Late Triassic and led to the exhumation of 7.5–10.5 km of crustal rocks by the end of the Middle Jurassic (ca. 160–150 Ma). The following phase resulted in 1–3 km of basement subsidence and occurred during the Late Jurassic and most of the Early Cretaceous. The basement rocks were then slowly brought to the surface after experiencing 2–3.5 km of exhumation throughout the Late Cretaceous and the Cenozoic. The timing of these episodes of exhumation and subsidence coincides with major tectonic and thermal events in relation with the evolution of the Atlantic and Tethys Oceans, indicating that the effects of their rifting and drifting extended beyond their presumed margins.

On the spatial distribution of seismicity and the 3D tectonic stress field in western Greece

We analyzed a large number of focal mechanisms and relocated earthquake hypocenters to investigate the geodynamics of western Greece, the most seismically active part of the Aegean plate-boundary zone. This region was seismically activated multiple times during the last decade, providing a large amount of enhanced quality new information that was obtained by the Hellenic Unified Seismological Network (HUSN). Relocated seismicity using a double-difference method appears to be concentrated above ∼35 km depth, exhibiting spatial continuity along the convergence boundary and being clustered elsewhere. Earthquakes are confined within the accreted sediments escarpment of the down-going African plate against the un-deformed Eurasian hinterland. The data arrangement shows that Pindos constitutes a seismic boundary along which large stress heterogeneities occur. In Cephalonia no seismicity is found to be related with the offshore Cephalonia Transform Fault (CTF). Onshore, NS crustal extension dominates, while in central and south Peloponnesus the stress field appears rotated by 90°. Shearing-stress obliquity by 30° is indicated along the major strike-slip faults, consistent with clockwise crustal rotation. Within the lower crust, the stress field appears affected by plate kinematics and distributed deformation of the lower crust and upper mantle, which guide the regional geodynamics.

Geomorphology and Neogene tectonic evolution of the Palomares continental margin (Western Mediterranean)

The Palomares continental margin is located in the southeastern part of Spain. The margin main structure was formed during Miocene times, and it is currently part of the wide deformation zone characterizing the region between the Iberian and African plates, where no well-defined plate boundary occurs. The convergence between these two plates is here accommodated by several structures, including the left lateral strike–slip Palomares Fault. The region is characterized by sparse, low to moderate magnitude (Mw <5.2) shallow instrumental earthquakes, although large historical events have also occurred. To understand the recent tectonic history of the margin we analyze new high-resolution multibeam bathymetry data and re-processed three multichannel seismic reflection profiles crossing the main structures. The analysis of seafloor morphology and associated subsurface structure provides new insights of the active tectonic features of the area. In contrast to other segments of the southeastern Iberian margin, the Palomares margin contains numerous large and comparatively closely spaced canyons with heads that reach near the coast. The margin relief is also characterized by the presence of three prominent igneous submarine ridges that include the Aguilas, Abubacer and Maimonides highs. Erosive processes evidenced by a number of scars, slope failures, gullies and canyon incisions shape the present-day relief of the Palomares margin. Seismic images reveal the deep structure distinguishing between Miocene structures related to the formation of the margin and currently active features, some of which may reactivate inherited structures. The structure of the margin started with an extensional phase accompanied by volcanic accretion during the Serravallian, followed by a compressional pulse that started during the Latemost Tortonian. Nowadays, tectonic activity offshore is subdued and limited to few, minor faults, in comparison with the activity recorded onshore. The deep Algero-Balearic Basin is affected by surficial processes, associated to halokinesis of Messinian evaporites.

Seismotectonics of northeastern Sicily and southern Calabria (Italy): New constraints on the tectonic structures featuring in a crucial sector for the central Mediterranean geodynamics

AbstractThe purpose of this study is to gain a better understanding on the tectonic structures featuring in a crucial sector of central Mediterranean area, including the Aeolian Islands, southern Calabria, and northeastern Sicily, where the convergence between Eurasian and African Plates has given rise to a complicated collisional/subduction complex. A high‐quality data set of about 3000 earthquakes has been exploited for local earthquake tomography and focal mechanisms computation together with available source mechanisms from published catalogues. The results depict new details of a network of faults which enables the concurrent existence of adjacent compressional and extensional domains. In particular, tomographic images, seismic events distribution, and focal mechanisms pinpoint the geometry and activity of a lithospheric‐scale tear faults system which, with a NW‐SE trend through Sicily and the Tyrrhenian and Ionian Seas, represents the southern edge of the Ionian subduction trench zone. At crustal depth, this tearing is well highlighted by a rotation of the maximum horizontal stress, moving across the area from west toward east. In addition, the shallow normal fault regime, characterizing the southern Calabria and northeastern Sicily mainland, south of the NW‐SE lineament, changes in the deeper part of the crust. Indeed, a NE‐SW earthquake distribution, gently dipping NW, and inverse fault solutions indicate a still active contractional deformation in eastern Sicily, caused by the Africa‐Eurasia convergence and well framed with the current compressive regime along the southern Tyrrhenian zone and at the front of the Sicilian Chain‐Foreland.

Seismicity constraints on stress regimes along Sinai subplate boundaries

The relative movement between African, Arabian and Eurasian plates has significantly controlled the tectonic process of Sinai subplate region, although its kinematics and precise boundaries are still doubtful. The respective subplate bounded on both sides by the Aqaba-Dead Sea transform fault to the east and the Gulf of Suez, the only defined part, to the west. Seismicity parameters, moment magnitude relation and fault plane solutions were combined to determine the active tectonics along the aforementioned boundaries. Seven shallow seismogenic zones were defined by the heterogeneity in stress field orientations. Along the eastern boundary, the average fault plane solution obtained from the moment tensor summation (MTS) reveals a sinistral strike-slip faulting mechanism. The corresponding seismic strain rate tensor showed that the present tectonic stress producing earthquakes along the boundary is dominated by both NW-SE compression and NE-SW dilatation. Towards the north, the average focal mechanism showed a normal faulting mechanism of N185°E compression and an N94°E extension in the Carmel Fairi seismic zone. On the other hand, the active crustal deformation along the western boundary (Gulf of Suez region) showed a prevailing tensional stress regime of NE to ENE orientations; producing an average fault plane solution of normal faulting mechanism. The seismic strain rate tensor reveals a dominant stress regime of N58°E extension and N145°E compression in consistence with the general tectonic nature in northeastern Africa. Finally, the extensional to strike-slip stress regimes obtained in the present study emphasize that the deformation accommodated along the Sinai subplate boundaries are in consistence with the kinematics models along the plate boundaries representing the northern extremity part of the Red Sea region.

14 C Ages of the Last Eruptive Stage of Faial Island Caldeira Volcano

Faial is one of the nine islands that form the Azores archipelago in the North Atlantic, characterized by a complex geodynamic setting dominated by the triple point where the North American, Eurasian, and African lithospheric plates meet. Faial Island comprises two central volcanoes and two basaltic fissure systems. The oldest central volcano is the Ribeirinha Volcano, on the northeast sector of the island. It is an extinct volcano, extensively dissected by the regional distensive faults of the Pedro Miguel Graben. The volcano has an age spanning from more than 850 ka BP to about 340 ka BP. The central portion of the island is formed by the Caldeira Volcano, a central volcano that has been active since before 440 ka BP. The ages of the basaltic fissure systems are less well constrained. The Horta Platform Fissure System, on the southeast sector of the island, has been active since more then 11 ka BP and its most recent activity is older than 6 ka BP. The Capelo Peninsula Fissure System, forming the west portion of the island, is a geomorphologically young region. This system has been active until the present and produced two historical eruptions, one in AD 1672–1673 and another in AD 1957–1958. DOI: 10.2458/azu_rc.57.17957

Seismostratigraphy and tectonic architecture of the Carboneras Fault offshore based on multiscale seismic imaging: Implications for the Neogene evolution of the NE Alboran Sea

In the SE Iberian Margin, which hosts the convergent boundary between the European and African Plates, Quaternary faulting activity is dominated by a large left-lateral strike–slip system referred to as the Eastern Betic Shear Zone. This active fault system runs along more than 450km and it is characterised by low to moderate magnitude shallow earthquakes, although large historical events have also occurred. The Carboneras Fault is the longest structure of the Eastern Betic Shear Zone, and its southern termination extends further into the Alboran Sea. Previously acquired high-resolution data (i.e. swath-bathymetry, TOBI sidescan sonar and sub-bottom profiler) show that the offshore Carboneras Fault is a NE–SW-trending upwarped zone of deformation with a length of 90km long and a width of 0.5 to 2km, which shows geomorphic features typically found in subaerial strike–slip faults, such as deflected drainage, pressure ridges and “en echelon” folds. However, the neotectonic, depth architecture, and Neogene evolution of Carboneras Fault offshore are still poorly known. In this work we present a multiscale seismic imaging of the Carboneras Fault (i.e. TOPAS, high-resolution multichannel-seismic reflection, and deep penetration multichannel-seismic reflection) carried out during three successive marine cruises, from 2006 to 2010. The new dataset allowed us to define a total of seven seismostratigraphic units (from Tortonian to Late Quaternary) above the basement, to characterise the tectonic architecture and structural segmentation of the Carboneras Fault, and to estimate its maximum seismic potential. We finally discuss the role of the basement in the present-day tectonic evolution of the Carboneras Fault, and explore the northern and southern terminations of the fault and how the strain is transferred to nearby structures.

MORFOTECTÓNICA DEL SEGMENTO CÁDIZ-MÁLAGA, SUR DE ESPAÑA

&lt;p&gt;Se presentan los resultados de una investigación morfotectónica del segmento continental de Cádiz a Málaga, zona occidental de interacción entre las placas africana y euroasiática. Aquí existe un sistema de 5 tipos de Unidades Territoriales (macrobloques= 2, mesobloques= 2, bloques= 29, microbloques= 44, y nanobloques= 202) en relaciones espacio-temporales actuales con una red de 29 alineaciones principales y 32 intersecciones o nudos. El 59% de los bloques es muy activo o activo, y el territorio tiene un valor de ~0.03 fracturas/km2 con 63 escarpes. Las zonas con mayor actividad están entre las localidades de Barbate-Torrecera-Sierra de las Cabras (en Cádiz) y Ronda-Embalse Gudaltela Cabras-Villalón (en Málaga). El segmento de Cádiz-Málaga tiene características similares a las de la zona colindante de Almería-Córdoba-Granada-Jaén-Murcia. Todo el trabajo sustentado en un SIG.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;&lt;p&gt;MORPHOTECTONICS OF THE CADIZ-MALAGA SEGMENT, SOUTHERN SPAIN&lt;/p&gt;&lt;p&gt;&lt;strong&gt;ABSTRACT&lt;/strong&gt;&lt;br /&gt; We present the results of a morphotectonic research of the Cadiz to Malaga continental segment, which is a western interaction zone between the African and Europe-Asian plates. There is a system of 5 types of Territorial Units (macroblocks= 2, mesoblocks= 2, blocks= 29, microblocks= 44, and nanoblocks= 202) in current space-time relations with a network of 29 main alignments and 32 intersections or junctions. Fifty-nine percent of the blocks are very active or active, and the territory has a mean value of ~0.03 fractures/km2 with 63 scarps. The most active zones are between Barbate-Torrecera-Sierra de las Cabras (in Cádiz) and Ronda-Embalse Gudaltela-Cabras-Villalon (in Málaga). This Cadiz-Malaga segment has similar characteristics to those determined for the adjacent zone of Almería-Córdoba-Granada-Jaén-Murcia. All data are in a GIS.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;&lt;p&gt;&lt;span&gt;&lt;br /&gt;&lt;/span&gt;&lt;/p&gt;

Cenozoic tectonic and climatic events in southern Iberian Peninsula: Implications for the evolutionary history of freshwater fish of the genus Squalius (Actinopterygii, Cyprinidae)

Southern Iberian freshwater ecosystems located at the border between the European and African plates represent a tectonically complex region spanning several geological ages, from the uplifting of the Betic Mountains in the Serravalian–Tortonian periods to the present. This area has also been subjected to the influence of changing climate conditions since the Middle–Upper Pliocene when seasonal weather patterns were established. Consequently, the ichthyofauna of southern Iberia is an interesting model system for analyzing the influence of Cenozoic tectonic and climatic events on its evolutionary history. The cyprinids Squalius malacitanus and Squalius pyrenaicus are allopatrically distributed in southern Iberia and their evolutionary history may have been defined by Cenozoic tectonic and climatic events. We analyzed MT-CYB (510 specimens) and RAG1 (140 specimens) genes of both species to reconstruct phylogenetic relationships and to estimate divergence times and ancestral distribution ranges of the species and their populations. We also assessed their levels of genetic structure and diversity as well as the amount of gene flow between populations. To investigate recent paleogeographical and climatic factors in southern Iberia, we modeled changes-through-time in sea level from the LGM to the present. Phylogenetic, geographic and population structure analyses revealed two well-supported species (S. malacitanus and S. pyrenaicus) in southern Iberia and two subclades (Atlantic and Mediterranean) within S. malacitanus. The origin of S. malacitanus and the separation of its Atlantic and Mediterranean populations occurred during the Serravalian–Tortonian and Miocene–Pliocene periods, respectively. These divergence events occurred in the Middle Pliocene and Pleistocene in S. pyrenaicus. In both species, Atlantic basins possessed populations with higher genetic diversity than Mediterranean, which may be explained by the Janda Lagoon. The isolation of S. malacitanus was earlier and related to the rising of the Betic Mountains. Divergence of its Atlantic and Mediterranean populations was associated with the creation of the freshwater systems of southern Iberia close to the Gibraltar Strait. The presence of S. pyrenaicus in southern Iberia may be the result of recent colonization associated with river capture, as demonstrated our biogeographic reconstruction.

Evaluation of the deformation parameters of the northern part of Egypt using Global Navigation Satellite System (GNSS)

The northern part of Egypt is a rapidly growing development accompanied by the increased levels of standard living particularly in its urban areas. From tectonic and seismic point of views, the northern part of Egypt is one of the interested regions. It shows an active geologic structure attributed to the tectonic movements of the African and Eurasian plates from one side and the Arabian plate from the other side. From historical point of view and recent instrumental records, the northern part of Egypt is one of the seismo-active regions in Egypt. The investigations of the seismic events and their interpretations had led to evaluate the seismic hazard for disaster mitigation, for the safety of the densely populated regions and the vital projects. In addition to the monitoring of the seismic events, the most powerful technique of Global Navigation Satellite System (GNSS) will be used in determining crustal deformation where a geodetic network covers the northern part of Egypt. Joining the GPS Permanent stations of the northern part of Egypt with the Southern part of Europe will give a clear picture about the recent crustal deformation and the African plate velocity. The results from the data sets are compared and combined in order to determine the main characteristics of the deformation and hazard estimation for specified regions. Final compiled output from the seismological and geodetic analysis will throw lights upon the geodynamical regime of these seismo-active regions. This work will throw lights upon the geodynamical regime and to delineate the crustal stress and strain fields in the study region. This also enables to evaluate the active tectonics and surface deformation with their directions from repeated geodetic observations. The results show that the area under study suffers from continuous seismic activity related to the crustal movements taken place along trends of major faults

About this title ‐ Magmatic Rifting and Active Volcanism

A major rifting episode began in the Afar region of northern Ethiopia in September 2005. Over a ten-day period, c. 2.5 km 3 of magma were intruded along a 60 km-long dyke separating the Arabian and Nubian plates. Over the next five years, a further 13 dyke intrusions caused continued extension, eruptions and seismicity. This activity led to a renewed international focus on the role of magmatism in rifting, with major international collaborative projects working in Afar and Ethiopia to study the ongoing activity and to place it in a broader context. This book brings together articles that explore the role of magmatism in rifting, from the initiation of continental break-up through to full seafloor spreading. We also explore the hazards related to rifting and the associated volcanism. This work has implications for our understanding of how continents break-up and the associated distribution of resources in rift basins and continental margins.

New insights on the seismogenic potential of the Eastern Betic Shear Zone (SE Iberia): Quaternary activity and paleoseismicity of the SW segment of the Carrascoy Fault Zone

AbstractThe Carrascoy Fault (CAF) is one of the main active faults that form part of the Eastern Betic Shear Zone, a 450 km fault system that accommodates most of the convergence between the Eurasian (Iberia) and Nubian plates in the Betic Cordillera, south Spain. Although the CAF represents a major earthquake threat to the nearby City of Murcia, studies on its Quaternary tectonics and seismogenic potential are scarce to date. We present evidence that supports the division of the CAF into two overlapping segments with contrasting tectonic structure, Quaternary activity, and landform control: a SW segment, characterized by a broad fold‐and‐thrust zone similar to the forebergs defined in the Gobi‐Altai region, and a NE segment, characterized by a sharp mountain front controlled by strike‐slip tectonics. We attribute the differentiation into these two segments to the stresses associated with topography, which in turn is a consequence of the shortening component, at the middle Pleistocene, after circa 217.4 ka. For the SW segment we infer the occurrence of 9 to 11, Mw 6.7 paleoearthquakes in the last 30.2 kyr, and a slip rate of 0.37 ± 0.08 m/kyr. We date the occurrence of the last surface rupture event after 2750 B.P., and we estimate an average recurrence period of major events of 3.3 ± 0.7 kyr.

Magmatic rifting and active volcanism: introduction

Abstract A major rifting episode began in the Afar region of northern Ethiopia in September 2005. Over a 10-day period, c. 2.5 km 3 of magma were intruded into the upper crust along a 60 km-long dyke separating the Arabian and Nubian plates. There was an intense seismic swarm and a small rhyolitic eruption; extension of up to 10 m occurred across the rift segment. Over the next five years, a further 13 dyke intrusions caused continued extension, eruptions and seismicity. The activity in Afar led to a renewed international focus on the role of magmatism in rifting, with major collaborative projects involving researchers from Ethiopia, the UK, the USA, France, Italy and New Zealand working in Afar and Ethiopia to study the ongoing activity and to place it in a broader context. This book brings together articles that explore the role of magmatism in rifting, from the initiation of continental break-up through to full seafloor spreading. We also explore the hazards related to rifting and the associated volcanism. This renewed focus on magmatism and its role in rifting has implications for our understanding of how continents break-up and the associated distribution of resources in rift basins and continental margins.

Could Geometry Demystify Patterns of Earth Quakes and Aftershocks? An Answer is Yes

In this article, a pioneering (geometric) approach based on a new what is named here Glued Bivariate Poisson (GBP) distribution is constructed to demystify the 21st century incidences of earthquakes and their aftershocks. A warning risk index for an earthquake or an aftershock to occur is formulated and computed for each of the thirteen major tectonic plates. This article reports a surprise and it is that there exists a geo angle constancy, 1.571 in the results pertaining to earthquakes or aftershocks in all the tectonic plates no matter what varying interlocked “glue level” among the African, Antarctica, Arabian, Australian, Caribbean, Coco’s, Eurasian, Indian, North American, Pacific, Philippine, South American and Scotia tectonic plates. The contents of this article identified higher risk plates, which include Eurasian, India, Pacific and Philippines plates, where earthquakes of Kathmandu, Nepal (on 26 April 2015) and Chich-Shima, Japan (on 30 May 2015) occurred as validations of the contents of this article. An interesting geologic-constancy of 1.571 is noticed based on our statistical approach and an appropriate representative random sampling.

Tracking the uplift of the Bolkar Mountains (south-central Turkey): evidence from apatite fission track thermochronology

Apatite fission track (AFT) thermochronology is applied to the Horozköy granitoid, which outcrops within the Bolkar Mountains (south-central Turkey). The region comprises the Niğde Massif to the north, the Inner Tauride Suture Zone, and the Central Taurides to the south. The Niğde Massif and the Central Taurides collided during the Eocene following north-dipping subduction of the Inner Tauride Ocean beneath the Niğde Massif. The Ulukışla Basin formed above this suture zone. The AFT ages range between 23 and 16 Ma, although there was no significant uplift or exhumation during this period. During the Oligo-Miocene, the region experienced a slow uplift and the collapse of the Tauride belt, in response to the mantle processes (roll-back, break-off, and/or slab tearing) related to the African plate and linked oceanic slab beneath the Anatolide-Taurides. The Central Taurides reached maximum height during the latest Miocene. The AFT modeling results indicate a fast exhumation in the late Miocene-Pleistocene, consistent with the biostratigraphic and field evidence.