The comparison of anisotropy of magnetic remanence with the anisotropy of magnetic susceptibility of the Dukla nappe from the Outer Western Carpathians

The Carpathians belong to the European Alpine system, which was formed during the convergence and collision of the European and African plates. The Polish segment of the Western Outer Carpathians is a north-verging thrust-and-fold belt composed largely of Lower Cretaceous to lower Miocene flysch. The belt comprises five rootless nappes: Skole, Subsilesian, Silesian, Dukla and Magura nappes. This paper presents the results of anisotropy of magnetic susceptibility (AMS), anisotropy of magnetic remanence (Anisotropy of Anhysteric Remanent Magnetization, AARM) and isothermal remanent magnetization (IRM) studies performed both in Oligocene turbidite sequences in the frontal part of the Dukla nappe and in olistostrome complex of the Lipowica quarry, topping the Silesian nappe in front of the Dukla nappe. For the study 102 individually oriented cores were drilled at nine geographically distributed localities. At each locality claystones were sampled, except Lipowica quarry, where silt and sandstone were also drilled. The AMS measurements showed that, the magnetic fabrics were dominantly foliated, with a weak but in the most cases well defined lineations, which correlate to the local strikes. At four localities the AMS lineations are aligned with the general (NW-SE) tectonic trend of the unit. The samples from Lipowica quarry and three other localities exhibit different, but still horizontal AMS lineations. At locality 6, the AMS lineation is vertical. In this case the question was if this peculiarity is due to strong deformation or mineralogical reasons. Because of the relatively low susceptibilities (1-3*10-4 SI), paramagnetic minerals can be importantcontributors to the AMS fabric. In order to study the magnetic fabric of the ferromagnetic mineral, which, according to the IRM measurements, most probably magnetite, AARM measurements were carried out so far on the samples from three localities and compared with the AMS fabric. We observed that, the difference between the AMS and AARM lineations at locality 8 is small. At locality 6 the AARM fabric is “normal” and parallel to the main tectonic trend of the Dukla nappe, and so becomes the AMS fabric after thermal demagnetization at 460°C. We interpret these phenomena as related to the presence of siderite in the rock, which is a paramagnetic mineral, known for its ability of creating inverse fabric in sediments. Concerning locality 1, the directions of the AMS and AARM lineations are quite different in all three rock types studied, but none of them are aligned with the main tectonic trend of the Dukla nappe. The above results outline a really complicated picture of the deformation history of the Dukla nappe, where the documented or suspected presence of the olistoliths may explain the often occurring local anomalies. Further AARM measurements are planned in the near future in order to understand better the tectonics of the Dukla nappe

The role of compressional tectonics, sedimentary transport and mineral composition on AMS and AARM fabrics. A case study of the flysch from the Dukla nappe, OuterWestern Carpatians, Poland

The Carpathians belong to the European Alpine system. The Polish segment of the Western Outer Carpathians is a north-verging thrust-and-fold belt composed largely of Lower Cretaceous to Lower Miocene flysch. The belt comprises the Skole, Subsilesian, Silesian, Dukla and Magura rootless nappes. Anisotropy studies were carried out both in Oligocene turbidite sequences of the Dukla nappe and in the olistostrome of the Lipowica quarry. For the study 102 individually oriented cores were drilled at nine geographically distributed localities. At each locality mudstones/claystones were sampled, except Lipowica quarry, where silt and sandstone were also drilled. Because of the relatively low susceptibilities (1-3*10-4 SI), paramagnetic minerals can be important contributors to the AMS fabric. AMS and AARM measurements were carried out and the fabrics were compared. Despite of the weak AMS lineations, the mean lineation direction is well defined in all cases on site/locality level. With one exception where the lineation is perpendicular to the bedding plane (due to the presence of siderite), the AMS lineations can be interpreted as due to compressional tectonics. Concerning the AARM lineations they are highly scattered in the sandstone, show a tendency for alignment in the silt and some of the mudstone/claystone sites, and are well clustered in the other cases. The AARM lineations for four localities correlate to the AMS, and the local strike. The AARM lineation of the siderite bearing rock is also sub-parallel to the local strike. In the remaining cases the AARM linations are suspected to be related to sedimentary transport. Due to the lack of solemarks at most localities this will be investigated systematically with photo-statistical grain shape analysis in oriented thin sections. X-ray diffraction measurements also will be carried out to identify the paramagnetic contributors to the AMS. Acknowledgments: This work was partly financed by the Hungarian Research Fund (OTKA) project no. K105245 and from a joint project of the Academies of Science of Poland and Hungary

Rigid ball-polyhedra in Euclidean 3-space

A ball-polyhedron is the intersection with non-empty interior of finitely many (closed) unit balls in Euclidean 3-space. One can represent the boundary of a ball-polyhedron as the union of vertices, edges, and faces defined in a rather natural way. A ball-polyhedron is called a simple ball-polyhedron if at every vertex exactly three edges meet. Moreover, a ball-polyhedron is called a standard ball-polyhedron if its vertex-edge-face structure is a lattice (with respect to containment). To each edge of a ball-polyhedron one can assign an inner dihedral angle and say that the given ball-polyhedron is locally rigid with respect to its inner dihedral angles if the vertex-edge-face structure of the ball-polyhedron and its inner dihedral angles determine the ball-polyhedron up to congruence locally. The main result of this paper is a Cauchy-type rigidity theorem for ball-polyhedra stating that any simple and standard ball-polyhedron is locally rigid with respect to its inner dihedral angles.Comment: 11 pages, 2 figure

Late Miocene to present day structural development of the Polish segment of the Outer Carpathians

This paper presents a few pieces of evidence on neotectonic structural evolution of the Polish segment of the Outer Carpathians. During the Late Neogene, structural development was largely controlled by normal faulting and block uplift. However, there are also indications of compressional stress setting, at least during the Pliocene and particularly within the medial and eastern parts of the belt. In the Quaternary, in turn, structural development has been mainly controlled by compressional stress arrangement, with \sigma _{1} orientated roughly perpendicular to the belt. The Pliocene-Quaternary tectonic mobility of the Polish Outer Carpathians has been relatively weak and mostly of thin-skinned character. Normal faults were formed on the margins of intramontane basins and in the western part of the belt. Rates of uplift of individual structures were variable and the amount of uplift was the greatest in the Late Pliocene and Early Quaternary times. Geomorphologically-detected zones of uplift are relatively narrow and arranged subparallel or under small angle in respect to the strike of principal thrusts and frontal parts of large slices. Such an arrangement is interpreted as resulting from the steepening of frontal thrusts due to horizontal compression within the overthrust flysch nappes. This hypothesis is confirmed by the results of recent break-out and GPS studies, as well as by focal solutions of some Outer Carpathian earthquakes

Defect flows in minimal models

In this paper we study a simple example of a two-parameter space of renormalisation group flows of defects in Virasoro minimal models. We use a combination of exact results, perturbation theory and the truncated conformal space approach to search for fixed points and investigate their nature. For the Ising model, we confirm the recent results of Fendley et al. In the case of central charge close to one, we find six fixed points, five of which we can identify in terms of known defects and one of which we conjecture is a new non-trivial conformal defect. We also include several new results on exact properties of perturbed defects and on the renormalisation group in the truncated conformal space approach.Comment: 35 pages, 21 figures. 1 reference adde

Multiscale Analysis of Spreading in a Large Communication Network

In temporal networks, both the topology of the underlying network and the timings of interaction events can be crucial in determining how some dynamic process mediated by the network unfolds. We have explored the limiting case of the speed of spreading in the SI model, set up such that an event between an infectious and susceptible individual always transmits the infection. The speed of this process sets an upper bound for the speed of any dynamic process that is mediated through the interaction events of the network. With the help of temporal networks derived from large scale time-stamped data on mobile phone calls, we extend earlier results that point out the slowing-down effects of burstiness and temporal inhomogeneities. In such networks, links are not permanently active, but dynamic processes are mediated by recurrent events taking place on the links at specific points in time. We perform a multi-scale analysis and pinpoint the importance of the timings of event sequences on individual links, their correlations with neighboring sequences, and the temporal pathways taken by the network-scale spreading process. This is achieved by studying empirically and analytically different characteristic relay times of links, relevant to the respective scales, and a set of temporal reference models that allow for removing selected time-domain correlations one by one

Coherent errors and readout errors in the surface code

We consider the combined effect of readout errors and coherent errors, i.e., deterministic phase rotations, on the surface code. We use a recently developed numerical approach, via a mapping of the physical qubits to Majorana fermions. We show how to use this approach in the presence of readout errors, treated on the phenomenological level: perfect projective measurements with potentially incorrectly recorded outcomes, and multiple repeated measurement rounds. We find a threshold for this combination of errors, with an error rate close to the threshold of the corresponding incoherent error channel (random Pauli-Z and readout errors). The value of the threshold error rate, using the worst case fidelity as the measure of logical errors, is 2.6%. Below the threshold, scaling up the code leads to the rapid loss of coherence in the logical-level errors, but error rates that are greater than those of the corresponding incoherent error channel. We also vary the coherent and readout error rates independently, and find that the surface code is more sensitive to coherent errors than to readout errors. Our work extends the recent results on coherent errors with perfect readout to the experimentally more realistic situation where readout errors also occur