The Papoose Flat Pluton of eastern California: a reassessment of its emplacement history in the light of new microstructural and crystallographic fabric observations

ABSTRACTOne of the most outstanding apparent examples in N America of a forcibly emplaced pluton is the Papoose Flat Pluton of eastern California. Sideways expansion of this granitic pluton, during emplacement into a series of Cambrian shelf strata, has been regarded by early workers as resulting in the observed intense crystal plastic deformation of the pluton's mylonitic border facies and surrounding country rocks. This deformation is evidenced by up to 90% thinning of individual stratigraphic layers within the pluton's metamorphic aureole, although such intense penetrative deformation of the country rocks is not observed outside the aureole.Previously published quartz c-axis fabrics associated with this deformation (and presented on projection planes oriented perpendicular to lineation) were interpreted as being symmetrical with respect to foliation and lineation, implying almost coaxial deformation histories. Such fabrics could be interpreted as indicating that the pluton evolved by “ballooning” as a result of new magma being intruded into its core during emplacement. However, a major problem with applying the strict ballooning model to the Papoose Flat Pluton is that while oblate strains would be expected to develop in association with a ballooning mechanism, the mylonitic rocks of this elongate WNW-ESE-trending pluton and its aureole are characterised by both a strongly developed foliation, which is concordant with the pluton's margin, and an intense, NW-SE trending, shallow plunging stretching lineation.Previously published fabrics from the Papoose Flat Pluton and its metamorphic aureole have been rotated on to a projection plane oriented parallel to lineation and perpendicular to foliation. Examination of the fabrics in this projection plane has revealed that they are in fact dominantly asymmetric, and that a constant sense of asymmetry is detected across the pluton, suggesting a consistent (top-to-the-SE) shear-sense. This new interpretation is strongly supported by microstructural and petrofabric analysis of additional L-S tectonites collected, during recent fieldwork, from both the aureole and quartz veins within the pluton's gneissic border facies. Thus mylonite formation around the Papoose Flat Pluton could have involved large-scale consistently oriented translation and associated shearing, rather than passive “blister-like” coaxial deformation associated with pluton ballooning. It should be noted that mylonitic deformation is restricted to the western half of the pluton, features indicative of a more “permitted” emplacement mechanism being found in the eastern portion of the pluton.The detected top-to-the-SE shear-sense could be interpreted as indicating that the granitic material forming the western part of the pluton was forcibly intruded in a northwestward direction from the pluton source as a nearly solidified wedge beneath a static cover of sedimentary rocks. Alternatively, the detected shear sense could also be interpreted as indicating SE-directed thrusting of the cover rocks over the underlying pluton, the western margin of the pluton suffering intense mylonitic deformation, while the eastern margin was located in a “stress-shadow” region. If this alternative interpretation is correct, then the deformation temperatures indicated by the pattern of quartz c-axis fabrics dictate that thrusting must either be synchronous with pluton emplacement, or at least have commenced during the early stages of pluton cooling.

Download Full-text

Rethinking the notion of the high-performing education system: A Daoist response

Research in Comparative and International Education ◽

10.1177/1745499920983694 ◽

2021 ◽

pp. 174549992098369

Author(s):

Charlene Tan

Keyword(s):

Education System ◽

Large Scale ◽

Alternative Interpretation ◽

Educational Systems ◽

Education Systems ◽

High Performing ◽

Mutual Learning ◽

System A ◽

High Performers ◽

Major Implication

This article challenges the dominant notion of the ‘high-performing education system’ and offers an alternative interpretation from a Daoist perspective. The paper highlights two salient characteristics of such a system: its ability to outperform other education systems in international large-scale assessments; and its status as a positive or negative ‘reference society’. It is contended that external standards are applied and imposed on educational systems across the globe, judging a system to be high- or low- performing, and consequently worthy of emulation or deserving of criticism. Three cardinal Daoist principles that are drawn from the Zhuangzi are expounded: a rejection of an external and oppressive dao (way); the emptying of one’s heart-mind; and an ethics of difference. A major implication is a celebration of a plurality of high performers and reference societies, each unique in its own dao but converging on mutual learning and appreciation.

Download Full-text

Bistability of somatic pattern memories: stochastic outcomes in bioelectric circuits underlying regeneration

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2019.0765 ◽

2021 ◽

Vol 376 (1821) ◽

pp. 20190765 ◽

Cited By ~ 2

Author(s):

Giovanni Pezzulo ◽

Joshua LaPalme ◽

Fallon Durant ◽

Michael Levin

Keyword(s):

Large Scale ◽

Computational Models ◽

State Of The Art ◽

Memory Representation ◽

Theme Issue ◽

Evolutionary Innovation ◽

New Interpretation ◽

The Brain

Nervous systems’ computational abilities are an evolutionary innovation, specializing and speed-optimizing ancient biophysical dynamics. Bioelectric signalling originated in cells' communication with the outside world and with each other, enabling cooperation towards adaptive construction and repair of multicellular bodies. Here, we review the emerging field of developmental bioelectricity, which links the field of basal cognition to state-of-the-art questions in regenerative medicine, synthetic bioengineering and even artificial intelligence. One of the predictions of this view is that regeneration and regulative development can restore correct large-scale anatomies from diverse starting states because, like the brain, they exploit bioelectric encoding of distributed goal states—in this case, pattern memories. We propose a new interpretation of recent stochastic regenerative phenotypes in planaria, by appealing to computational models of memory representation and processing in the brain. Moreover, we discuss novel findings showing that bioelectric changes induced in planaria can be stored in tissue for over a week, thus revealing that somatic bioelectric circuits in vivo can implement a long-term, re-writable memory medium. A consideration of the mechanisms, evolution and functionality of basal cognition makes novel predictions and provides an integrative perspective on the evolution, physiology and biomedicine of information processing in vivo . This article is part of the theme issue ‘Basal cognition: multicellularity, neurons and the cognitive lens’.

Download Full-text

Superposed structures in the Mona Complex at Rhoscolyi Ynys Gybi, North Wales

Geological Magazine ◽

10.1017/s0016756800019567 ◽

1992 ◽

Vol 129 (4) ◽

pp. 475-490 ◽

Cited By ~ 6

Author(s):

H. Roper

Keyword(s):

Simple Shear ◽

Large Scale ◽

Axial Direction ◽

Kink Band ◽

Alternative Interpretation ◽

First Episode ◽

Band Model ◽

Kink Bands ◽

The North ◽

Island Group

AbstractThe Bedded Series of the Mona Complex at Rhoscolyn comprises two groups of clastic metasediments: the Holy Island Group, consistingof quartzites, impure psammites and pelites, with well-preserved bedding, is overlain conformably by the New Harbour Group, which is for the most parthomogeneously semi-pelitic without surviving bedding. Both groups have undergone the same two major tectono-metamorphic episodes, but with differing response. In the Holy Island Group the first episode (Dx) produced nearly upright and upward-facing folds (Fx) with an axial planar foliation (Sx), which varies from an anastomosing or rough-spaced cleavage in quartzites to a penetrative phyllitic schistosity in pelites. In the New Harbour Group Dx has generally obliterated original bedding surfaces, replacing them with a composite foliation (Sx) of fine compositional banding and a penetrative schistosity, together with a stretching lineation (Lx), the latter being at a high angle to the Fx axial direction. The Dx structures are attributed to a major episode of compressional tectonics.The structures attributed to the second deformation (Dy) includestrata-bound sets of quartz-filled tension fractures (attributed by most previous authors to an earlier episode), abundant NNW-verging asymmetric folds (Fy) of Sx, and a sporadically developed set of shear fractures which constitute a crenulation cleavage (Sy) axial planar to the folds. It is suggested that all these structures were produced by a single agency. One interpretation is that the observed shear fractures and folded tension fractures correspond fairly closely to and provide a natural analogy of those obtained in the classical simple shear experimentsof Riedel. In this case all the Dy structures can be accounted for by the action of a large-scale simple shear couple (Cy), whose vergence and shallow dip were both towards the NNW. Such a mechanism may imply a gravity-dominated regime of net horizontal extension in a NNW-SSE direction, with extension being less constrained to the north than to the south. J. W. Cosgrove has suggested an alternative interpretation, that all the Dy structures can be explained as reverse kink bands; the simple shear interpretation is here preferred because the angle between Sy and the estimated direction of Pmax during Dy was < 45°; the kink band model would require an angle > 45°.The fact that cleavage vergence boundaries for both Sx and Sy occur close to the hinge zone of the Rhoscolyn Antiform is consistent with either Dx or Dy age for the initiation of this fold. However, when fold limb length (or limb rotation) vergence is considered, the presence of an Fx0 vergence boundary but absence of an Fxy vergence boundary (and by implication of an Fy0 boundary) is consistent with a Dx age but difficult to reconcile with a Dy age.

Download Full-text

Parallel Object-Oriented Computation Applied to a Finite Element Problem

Scientific Programming ◽

10.1155/1993/859092 ◽

1993 ◽

Vol 2 (4) ◽

pp. 133-144 ◽

Cited By ~ 2

Author(s):

Jon B. Weissman ◽

Andrew S. Grimshaw ◽

R.D. Ferraro

Keyword(s):

Finite Element ◽

Message Passing ◽

Large Scale ◽

Processing System ◽

Object Oriented ◽

Data Parallel ◽

Programming Tools ◽

Comparable Performance ◽

Oriented Parallel ◽

Performance Results

The conventional wisdom in the scientific computing community is that the best way to solve large-scale numerically intensive scientific problems on today's parallel MIMD computers is to use Fortran or C programmed in a data-parallel style using low-level message-passing primitives. This approach inevitably leads to nonportable codes and extensive development time, and restricts parallel programming to the domain of the expert programmer. We believe that these problems are not inherent to parallel computing but are the result of the programming tools used. We will show that comparable performance can be achieved with little effort if better tools that present higher level abstractions are used. The vehicle for our demonstration is a 2D electromagnetic finite element scattering code we have implemented in Mentat, an object-oriented parallel processing system. We briefly describe the application. Mentat, the implementation, and present performance results for both a Mentat and a hand-coded parallel Fortran version.

Download Full-text

Structural characteristics of a developing turbulent planar jet

Journal of Fluid Mechanics ◽

10.1017/s0022112086002288 ◽

1986 ◽

Vol 163 ◽

pp. 227-256 ◽

Cited By ~ 85

Author(s):

F. O. Thomas ◽

V. W. Goldschmidt

Keyword(s):

Large Scale ◽

Structural Characteristics ◽

Energy Spectra ◽

Two Dimensional ◽

Structural Pattern ◽

Potential Core ◽

Planar Jet ◽

Fluctuation Phase ◽

Oriented Parallel ◽

Phase Angles

An experimental study of the developing structural characteristics of a two-dimensional jet in an extremely quiet environment was performed. The jet, at an exit Reynolds number of 6000 and with fluctuation intensity under 0.2% at the mouth, was operated within a large anechoic room. Measurements of energy spectra, fluctuation phase angles and two-dimensionality led to the inference of structural patterns in the flow. These patterns are initially characterized by relatively strong symmetric modes exhibiting limited two-dimensionality and oriented parallel to the mouth of the jet. Subsequent downstream evolution led to the formation of an antisymmetric pattern beyond the jet potential core and the associated development of extended structures possessing a definite large lateral inclination. The results of this work suggest a developing large-scale structural pattern more complicated than previously supposed.

Download Full-text

Slave Religiosity in the Roman Middle Republic

Classical Antiquity ◽

10.1525/ca.2017.36.2.317 ◽

2017 ◽

Vol 36 (2) ◽

pp. 317-369 ◽

Cited By ~ 1

Author(s):

Dan-el Padilla Peralta

Keyword(s):

Material Culture ◽

Religious Experience ◽

Large Scale ◽

Black Atlantic ◽

Republican Rome ◽

New Interpretation

This article proposes a new interpretation of slave religious experience in mid-republican Rome. Select passages from Plautine comedy and Cato the Elder's De agri cultura are paired with material culture as well as comparative evidence—mostly from studies of Black Atlantic slave religions—to reconstruct select aspects of a specific and distinctive slave “religiosity” in the era of large-scale enslavements. I work towards this reconstruction first by considering the subordination of slaves as religious agents (Part I) before turning to slaves’ practice of certain forms of religious expertise in the teeth of subordination and policing (II and III). After transitioning to an assessment of slave religiosity's role in the pursuit of freedom (IV), I conclude with a set of methodological justifications for this paper's line of inquiry (V).

Download Full-text

Aeolian-fluvial sediments as palaeoenvironmental records in the eastern Qaidam Basin, NE Tibetan Plateau, since MIS6

10.5194/egusphere-egu2020-21453 ◽

2020 ◽

Author(s):

Lupeng Yu ◽

Noam Greenbaum ◽

Joel Roskin

Keyword(s):

Tibetan Plateau ◽

Large Scale ◽

Asian Summer Monsoon ◽

Qaidam Basin ◽

Sedimentary Facies ◽

Fluvial Sediments ◽

Last Deglaciation ◽

Aeolian Sand ◽

The Holocene ◽

New Interpretation

Aeolian sediments sensitively respond to climatic changes. Continuous Quaternary loess deposits plays important roles in palaeoclimatic reconstructions. However, application of aeolian sand for such reconstructions is limited by its discontinuous depositional nature. Aeolian-fluvial sediments are widely distributed in arid and semi-arid regions where dunefields interact with watercourses. These palaeoenvironmental archives have been sparsely studied mainly due to their mixed character that requires new interpretation approaches.We have found that climate fluctuations lead good preservation of aeolian sand deposits that underlay fluvial sediments, making the sedimentary records more continuous. In this study, aeolian and fluvial sediments (elevation of 3400-3500 m a.s.l.) were studied in the eastern margin of Qaidam Basin (QB), northeastern Tibetan Plateau to reconstruct palaeoenvironmental and palaeoclimatic changes since the MIS6, based on sedimentary facies, 120 OSL ages (with age range of 143-1 ka), grain size distribution, MS, TOC, and carbonates.Within a deeply (10-65 m) incised 1.5-km-long valley, aeolian-fluvial cycles displayed frequent dune-damming of a stream since MIS6. Dune sands were dated to MIS's 6, 5d, 4, 3c, 3a, and the last deglaciation, while fluvial and dune-dammed lake sediments were dated to MIS's 5c, 3c, 3a, and deglaciation.Large-scale A-F interactions mainly occurred during MIS3 and deglaciation, when the QB dunefields were still mobile after LGM and MIS4 and precipitation started to increase. No ages fall within LGM, suggesting an extremely arid and windy environment in which the dune sand kept reworking and cannot record OSL ages. This further confirms that only with the covering of fluvial sediments, aeolian sand can be well preserved. On the other hand, OSL ages of aeolian sand might only present periods when aeolian activities were not too strong.During the Holocene, loess-paleosol accumulated in the QB margins, with loess accumulation since 10 ka and development of paleosols during ca. 8.5-3 ka, the Holocene optimum. These results demonstrate that aeolian-fluvial sediments are important palaeoenvironmental records in arid region and indicate that the climate of the eastern QB was mainly controlled by the temperature (solar insolation) and precipitation (Asian Summer Monsoon) changes since MIS6. &#160;

Download Full-text

Gravitational collapse and extension along a mid-crustal detachment: the Lough Derg Slide, northwest Ireland

Geological Magazine ◽

10.1017/s0016756800017611 ◽

1991 ◽

Vol 128 (4) ◽

pp. 345-354 ◽

Cited By ~ 20

Author(s):

G. I. Alsop

Keyword(s):

Large Scale ◽

Gravitational Instability ◽

Granulite Facies ◽

Crustal Thickening ◽

Transport Direction ◽

High Pressure Granulite ◽

Shear Sense ◽

Facies Metamorphism ◽

Peak Metamorphism ◽

Normal Sense

AbstractPre-Caledonian basement is juxtaposed with an inverted Upper Dalradian cover sequence along the Lough Derg Slide, in south Donegal, northwest Ireland. Shear-sense criteria indicate that the Dalradian Succession is translated via oblique dextral thrusting over high pressure granulite facies basement in the footwall. Crustal thickening induced by large scale folding associated with this ductile thrusting resulted in mid-amphibolite facies metamorphism adjacent to the sole of the Dalradian nappe. Subsequent to peak metamorphism, the overthickened Dalradian cover sequence suffered heterogenous deformation associated with ductile extension concentrated in the strain-softened mylonites of the hangingwall. The oblique ductile thrusts initiated during crystal thickening were reactivated in a normal sense. Pre-existing fold axes rotated towards the extensional transport direction, which is marked by a secondary stretching lineation with associated S–C fabrics. Ductile extension and hangingwall collapse are considered to be related to gravitational instability induced by the earlier crustal thickening episode.

Download Full-text

The Memory That Remembers Us

10.26686/wgtn.17019614 ◽

2021 ◽

Author(s):

◽

Mitchell Jones

Keyword(s):

Natural Environment ◽

Design Theory ◽

Architectural Design ◽

Large Scale ◽

Design Research ◽

Outer Space ◽

Full Range ◽

Design Work ◽

New City ◽

New Interpretation

Future habitation of earth is an ever-increasing concern, with the proliferation of problems such as overpopulation, climate change, nonviable waste disposable methods and over-consumption of natural resources. These issues are influencing some contemporary entrepreneurs to consider ways of moving away from earth, to new habitations in space where we can survive if the earth becomes uninhabitable. Amazon CEO Jeff Bezo is currently engaging technicians and engineers to design plans for a city in space. But architectural design theory, in addition to engineering, must play a fundamental role in such a project, if it is to meet the social, cultural and political needs of its inhabitants. People on earth benefit significantly from the ability to engage with the natural environment. But in outer space, this is not a condition that normally would be considered viable. In a space city, by default the traditional notion of an outside landscape setting needs to occur inside. This imperative becomes one of the principal reasons why this thesis looks at biophilia as a direction for the design research experiments, since biophilic systems at a large scale can provide a sense of an ‘outside’ landscape even ‘within’ the architecture of the design research. This thesis advances this concept further by proposing that the occupants can live within such a system, rather than peripheral to it, enabling the occupants to become a fundamental part of a working system. With the intention of exploring design concepts for a city in space, the first aim of the thesis is to consider how to incorporate a ‘natural environment’ into people’s lives, even within an ‘architectural’ context where no access to a traditional natural environment is available. The first thesis aim is to achieve this by integrating biophilic systems throughout the design, thereby providing an environmental landscape within which people can interact, within an internalised architectural construct. The second aim of the thesis is to consider how to apply sustainability to an entire city. By designing an entire city as an integrated set of biophilic ‘systems’, the thesis proposes that each component of the new urban environment becomes participatory – and they become fundamental parts of that system. The overall system can be conceived in relation to sub-systems, systems working on macro and micro levels, relating to the full range of urban to human scales. The third aim of the thesis is to consider how the architectural identity of a future city would be defined if the multicultural future city is not associated with any traditional site, culture, or architectural heritage. The thesis proposes that if the new city is designed as an overall set of biophilic systems, then the typological identity of the new architecture / new city could arise from the biophilic systems’ environmental as well as mechanical components–integrated with the related habitational systems. In this way, the architectural identity of the ‘new city’ is conceived as systems-based, rather than arising from historical architectural precedents that are no longer applicable in a fully enclosed city in space. This thesis asks the question: how can pressing issues such as global scarcity and severe environmental transformation be strategically represented to the public through politically motivated ‘speculative’ architecture? Using Factory Fifteen, a visual studio that works in architectural communication, combined with design work described in Chris Abbot’s novel Xavier of the World as a provocative generator of a speculative design as well as a driver for the site and programme, the architecture of a city in space is used to illustrate a new interpretation of physical, social, economic, cultural and political parameters for 21st century architecture.

Download Full-text