scholarly journals Nanocrystalline Principal Slip Zones and Their Role in Controlling Crustal Fault Rheology

Minerals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 328 ◽  
Author(s):  
Berend A. Verberne ◽  
Oliver Plümper ◽  
Christopher J. Spiers
Keyword(s):  
Structural Characteristics ◽  
Seismogenic Zone ◽  
Diffusion Creep ◽  
Fault Rock ◽  
Crystallographic Preferred Orientation ◽  
Rock Types ◽  
Slip Surfaces ◽  
Wide Range ◽  
Localized Shear Deformation ◽  
Fault Displacement

Principal slip zones (PSZs) are narrow (<10 cm) bands of localized shear deformation that occur in the cores of upper-crustal fault zones where they accommodate the bulk of fault displacement. Natural and experimentally-formed PSZs consistently show the presence of nanocrystallites in the <100 nm size range. Despite the presumed importance of such nanocrystalline (NC) fault rock in controlling fault mechanical behavior, their prevalence and potential role in controlling natural earthquake cycles remains insufficiently investigated. In this contribution, we summarize the physical properties of NC materials that may have a profound effect on fault rheology, and we review the structural characteristics of NC PSZs observed in natural faults and in experiments. Numerous literature reports show that such zones form in a wide range of faulted rock types, under a wide range of conditions pertaining to seismic and a-seismic upper-crustal fault slip, and frequently show an internal crystallographic preferred orientation (CPO) and partial amorphization, as well as forming glossy or “mirror-like” slip surfaces. Given the widespread occurrence of NC PSZs in upper-crustal faults, we suggest that they are of general significance. Specifically, the generally high rates of (diffusion) creep in NC fault rock may play a key role in controlling the depth limits to the seismogenic zone.

scholarly journals Introduction to redundancy rules: the continuous wavelet transform comes of age

2018 ◽  
Vol 376 (2126) ◽  
pp. 20170258 ◽  
Author(s):  
Paul S. Addison
Keyword(s):  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
State Of The Art ◽  
Structural Characteristics ◽  
Continuous Wavelet ◽  
Theme Issue ◽  
Current State ◽  
Analysis Methods ◽  
Wide Range ◽  
New Form

Redundancy: it is a word heavy with connotations of lacking usefulness. I often hear that the rationale for not using the continuous wavelet transform (CWT)—even when it appears most appropriate for the problem at hand—is that it is ‘redundant’. Sometimes the conversation ends there, as if self-explanatory. However, in the context of the CWT, ‘redundant’ is not a pejorative term, it simply refers to a less compact form used to represent the information within the signal. The benefit of this new form—the CWT—is that it allows for intricate structural characteristics of the signal information to be made manifest within the transform space, where it can be more amenable to study: resolution over redundancy. Once the signal information is in CWT form, a range of powerful analysis methods can then be employed for its extraction, interpretation and/or manipulation. This theme issue is intended to provide the reader with an overview of the current state of the art of CWT analysis methods from across a wide range of numerate disciplines, including fluid dynamics, structural mechanics, geophysics, medicine, astronomy and finance. This article is part of the theme issue ‘Redundancy rules: the continuous wavelet transform comes of age’.

STUDY OF HETEROMOLECULAR INTERACTION OF NONAQUEOUS BINARY SOLUTIONS

2020 ◽  
Vol 22 (2) ◽  
pp. 111-114
Author(s):  
D.T. Bozorova ◽  
Sh.P. Gofurov ◽  
A.M. Kokhkharov ◽  
O.B. Ismailova
Keyword(s):  
Binary Mixtures ◽  
Mole Fraction ◽  
Molecular Interactions ◽  
Weak Interactions ◽  
Structural Characteristics ◽  
Refractive Indices ◽  
Binary Solutions ◽  
Wide Range

In this work, the refractometry method was used to study of the molecular interactions and structural characteristics of dimethylformamide-ethanol and cyclohexane-ethanol binary mixtures. The refractive indices of mixtures were measured over a wide range of dimethylformamide and cyclohexane concentrations (0−1.0 mole fractions) at 25°С. It has been shown that heteromolecular complexes in binary solutions are formed at the concentration of ∼0.5 mole fraction of those compounds due to strong H-bonds. Relatively weak interactions are determined at a concentration of ∼0.2 and ∼0.9 mole fraction of dimethylformamide and ∼0.2 and ∼0.8 mole fraction of cyclohexane.

Study of Properties of Expanded Graphite – Polymer Porous Composite by Acoustic Emission Method

2013 ◽  
Vol 58 (4) ◽  
pp. 1331-1336 ◽  
Author(s):  
J. Berdowski ◽  
S. Berdowska ◽  
F. Aubry
Keyword(s):  
Acoustic Emission ◽  
Structural Changes ◽  
Structural Characteristics ◽  
Physical And Mechanical Properties ◽  
Expanded Graphite ◽  
Composite Membranes ◽  
Acoustic Emission Method ◽  
Emission Method ◽  
Graphite Composite ◽  
Wide Range

Abstract The purpose of this paper was to investigate the physical and mechanical properties of compressed expanded graphite (CEG) and their porous derivatives after impregnation, polymerization; and carbonization by the use of acoustic emission method (AE). The mechanical and structural characteristics of compressed expanded graphite and their three groups of porous composites after each technological process are presented and discussed. The measurements of acoustic emission parameters in these materials were carried out at wide range of frequency of the waves (0.1÷2.5 MHz). The changes of two of parameters: - AE pulses counts rate and spectrum distribution of AE waves - are presented in this paper. The analysis of the respective parameters AE also gives possibility to determine the micro- and macro structural changes of materials at different levels of technological processes. Applications of these materials as catalysts with high specific surface make them very interesting subject of study. Also compressed expanded graphite composite membranes prepared from furfuryl alcohol polymers are promising for gas separation.

scholarly journals Evidence of mingling between contrasting magmas in a deep plutonic environment: the example of Várzea Alegre, in the Ribeira Mobile Belt, Espírito Santo, Brazil

2001 ◽  
Vol 73 (1) ◽  
pp. 99-119 ◽  
Author(s):  
SILVIA R. MEDEIROS ◽  
CRISTINA M. WIEDEMANN-LEONARDOS ◽  
SIMON VRIEND
Keyword(s):  
Partial Melting ◽  
Granitic Magma ◽  
Geochemical Data ◽  
Mobile Belt ◽  
Tholeiitic Magma ◽  
Rock Types ◽  
Upper Proterozoic ◽  
Incompatible Elements ◽  
Wide Range ◽  
Intermediate Rock

At the end of the geotectonic cycle that shaped the northern segment of the Ribeira Mobile Belt (Upper Proterozoic to Paleozoic age), a late to post-collisional set of plutonic complexes, consisting of a wide range of lithotypes, intruded all metamorphic units. The Várzea Alegre Intrusive Complex is a post-collisional complex. The younger intrusion consists of an inversely zoned multistage structure envolved by a large early emplaced ring of megaporphyritic charnoenderbitic rocks. The combination of field, petrographic and geochemical data reveals the presence of at least two different series of igneous rocks. The first originated from the partial melting of the mantle. This was previously enriched in incompatible elements, low and intermediate REE and some HFS-elements. A second enrichment in LREE and incompatible elements in this series was due to the mingling with a crustal granitic magma. This mingling process changed the composition of the original tholeiitic magma towards a medium-K calc-alkalic magma to produce a suite of basic to intermediate rock types. The granitic magma from the second high-K, calc-alkalic suite originated from the partial melting of the continental crust, but with strong influence of mantle-derived melts.

scholarly journals Youth Labor Market Integration in European Regions

2020 ◽  
Vol 12 (9) ◽  
pp. 3813
Author(s):  
Ruggero Cefalo ◽  
Rosario Scandurra ◽  
Yuri Kazepov
Keyword(s):  
Labor Market ◽  
Market Integration ◽  
Structural Characteristics ◽  
Youth Unemployment ◽  
School To Work ◽  
Labor Market Participation ◽  
The European Union ◽  
Labor Market Integration ◽  
Youth Labor Market ◽  
Wide Range

Countries’ institutional configurations and structural characteristics play an important role in shaping transitions from school to work. Recent empirical evidence shows significant regional and territorial differences in youth unemployment and labor market participation. Along this research strand, we argue in favor of a place-sensitive approach to youth labor market integration in order to address the regional disparities of young people’s opportunities. In order to investigate the synergic effect of different contextual configurations, we construct a composite measure, namely, the youth labor market integration (YLMI) index. This considers a wide range of indicators of the access, exclusion, and duration of the transition into employment at the regional level. The YLMI index allows cross-regional and longitudinal comparisons of the European Union (EU) local labor markets and youth employment opportunities.

scholarly journals Heparan Sulfate Proteoglycan Signaling in Tumor Microenvironment

2020 ◽  
Vol 21 (18) ◽  
pp. 6588 ◽  
Author(s):  
Valeria De Pasquale ◽  
Luigi Michele Pavone
Keyword(s):  
Tumor Microenvironment ◽  
Heparan Sulfate ◽  
Cancer Progression ◽  
Structural Characteristics ◽  
Tumor Type ◽  
Wide Range ◽  
Functional Features ◽  
Complex Structural ◽  
Tumor Cell Behavior ◽  
Living Organisms

In the last few decades, heparan sulfate (HS) proteoglycans (HSPGs) have been an intriguing subject of study for their complex structural characteristics, their finely regulated biosynthetic machinery, and the wide range of functions they perform in living organisms from development to adulthood. From these studies, key roles of HSPGs in tumor initiation and progression have emerged, so that they are currently being explored as potential biomarkers and therapeutic targets for cancers. The multifaceted nature of HSPG structure/activity translates in their capacity to act either as inhibitors or promoters of tumor growth and invasion depending on the tumor type. Deregulation of HSPGs resulting in malignancy may be due to either their abnormal expression levels or changes in their structure and functions as a result of the altered activity of their biosynthetic or remodeling enzymes. Indeed, in the tumor microenvironment, HSPGs undergo structural alterations, through the shedding of proteoglycan ectodomain from the cell surface or the fragmentation and/or desulfation of HS chains, affecting HSPG function with significant impact on the molecular interactions between cancer cells and their microenvironment, and tumor cell behavior. Here, we overview the structural and functional features of HSPGs and their signaling in the tumor environment which contributes to tumorigenesis and cancer progression.

Metamorphic evolution of the Karimnagar granulite terrane, Eastern Dharwar Craton, south India

2010 ◽  
Vol 148 (1) ◽  
pp. 112-132 ◽  
Author(s):  
D. PRAKASH ◽  
I. N. SHARMA
Keyword(s):  
Granulite Facies ◽  
Dharwar Craton ◽  
Ultramafic Rocks ◽  
Chemical Compositions ◽  
Eastern Dharwar Craton ◽  
Geochronological Data ◽  
Rock Types ◽  
Wide Range ◽  
The Subject ◽  
Lower Crustal

AbstractThe Karimnagar granulite terrane is an integral part of the Eastern Dharwar Craton (EDC), India, having been the subject of much interest because of the only reported granulite facies rocks in the EDC. It shows a large variety of rock types with a wide range of mineral parageneses and chemical compositions, namely charnockites (Opx+Pl+perthite+Qtz±Bt±Grt), gneisses (Opx+Crd+Bt+Pl+Qtz+perthite±Sil±Grt±Spl; Bt+Qtz+Pl±Crd±Hbl±Spl), mafic granulites (Cpx+Pl+Qtz±Opx±Hbl), quartz-free granulites (Spr+Spl+Bt+Crd+Kfs+Crn; Bt+Crd+Kfs±Crn±Spl±Krn; And+Bt+Kfs+Chl), granites (Qtz+Pl+Kfs±Bt±Hbl), altered ultramafic rocks (Chl+Trem+Tlc), metadolerites (Cpx+Pl±Bt±Qtz±Chl), banded magnetite quartzites and quartzites. Andalusite- and chlorite-bearing assemblages presumably suggest a retrograde origin. Investigation of quartz-free granulites of the area brings out some interesting and important observations, reflecting the presence of refractory phases. These granulites are devoid of sillimanite and contain corundum instead. Reaction textures in the gneisses include breakdown of garnet to form coronas and symplectites of orthopyroxene+cordierite, formation of cordierite from garnet+sillimanite+quartz and late retrograde biotite and biotite+quartz symplectites. In the mafic granulites, inclusions of quartz and hornblende within orthopyroxene are interpreted as being a part of the prograde assemblage. At a later stage orthopyroxene is also rimmed by hornblende. The quartz-free granulites display a variety of spectacular coronas, for example, successive rims on corundum consisting of spinel+sapphirine+cordierite±orthopyroxene, rare skeletal symplectitic intergrowth of sapphirine+cordierite+potash feldspar, and late retrograde formation of chlorite, corundum, spinel and andalusite from sapphirine±cordierite. Based on chemographic relationships and petrogenetic grids, a sequence of prograde, isothermal decompressive and retrograde reactions have been inferred. Quartz-free sapphirine granulites and mafic granulites record the highest P–T conditions (~7 kbar, 850°C), whereas the gneisses were formed at lower P–T conditions (~5 kbar, 800°C). In addition, the presence of andalusite-bearing rocks suggests a pressure of around 2.5 kbar. This change in pressure from 7 kbar to around 2.5 kbar suggests a decompressive path for the evolution of granulites in the study area, which indicates an uplift for the granulite-facies rocks from lower crustal conditions. The implications for supercontinent history are also addressed in light of available geochronological data.

Changes in the location of the nucleation point of slip events on ancient normal faults

2020 ◽  
Author(s):  
Efstratios Delogkos ◽  
Conrad Childs ◽  
Tom Manzocchi ◽  
John Walsh
Keyword(s):  
Continuous Mapping ◽  
Fault Slip ◽  
Propagation Direction ◽  
Normal Faults ◽  
Northern Greece ◽  
Slip Surfaces ◽  
Local Propagation ◽  
Lignite Mine ◽  
Fault Trace ◽  
Fault Displacement

&lt;p&gt;The lack of an unambiguous method for determining the propagation direction of slip events on faults over significant time periods limits our understanding of the long-term stability of fault slip propagation directions. A geological means for determining the propagation direction of slip events during the growth of faults is provided by mutually cross-cutting faults and bed-parallel slip-surfaces in the Ptolemais Basin, northern Greece.&lt;/p&gt;&lt;p&gt;In the Kardia lignite mine, Ptolemais Basin, bed-parallel slip surfaces intermittently offset the Quaternary faults as they grew to form discontinuities on otherwise continuous fault surfaces. Subsequent fault slip increments bypassed these discontinuities to re-establish a continuous fault trace and leave an associated &amp;#8216;dead&amp;#8217; splay. The geometry and displacement distributions at these fault/bed-parallel slip intersections record the fault displacement at the time of bed-parallel slip and whether the next fault slip increment had an upwards or downwards component to its local propagation vector.&lt;/p&gt;&lt;p&gt;A database (N = 88) of slip propagation directions and fault throws was derived from continuous mapping of mine faces during lignite extraction over an eight year period. The data demonstrate a clear relationship between slip propagation direction and the accumulation of fault displacement on individual faults. During the early stages of fault growth, slip events propagated almost exclusively upwards through the mined sequence, but later stages of growth are marked by slip events showing both upward and downward components of propagation. The data therefore demonstrate that the location of the point of initiation of fault slip events on these Quaternary faults varied over the fault surfaces as the faults grew.&lt;/p&gt;&lt;p&gt;The emergence of systematic results from our analyses suggests that cross-cutting relationships between other synchronously active structures (e.g. conjugate faults) can provide a robust means for determining the propagation directions of slip events on ancient faults at outcrop.&lt;/p&gt;

Early Modern Sport

2017 ◽  
Author(s):  
Mike Huggins
Keyword(s):  
Early Modern ◽  
Structural Characteristics ◽  
Common People ◽  
Wide Range ◽  
Royal Courts ◽  
The Common

The early modern, however defined, is a “sporting” period whose formal-structural characteristics and the extent of its continuity with modern sport are both still often debated. This chapter argues that it played a much more important role than is often recognized in the development of modern sports. Even though sport could sometimes be morally, religiously, and politically problematic, “sporting” material could then be found in a wide range of sources, from recreational guidebooks, manuals, and personal papers to fiction and newspapers. Such material was often linked to the lives of royal courts and the “better sort” rather than the common people, about whom, like women’s involvement, we know less. The more widespread development of rules was encouraged by their association with betting practices. The period also saw new sports lifestyles, better playing skills, new forms of associativity and institutionalization, slowly growing standardization, and the slow emergence of professionalism.

Sign in / Sign up

Export Citation Format

Share Document