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Piggyback basins are common and well-studied features of thrust belts, but they are also known to form in front of advancing ice sheets. However, these glacitectonically developed basins and their syn-glacitectonic fillings have so far received little attention. Here, we present a detailed study of a cliff section on Jasmund peninsula, SW Baltic Sea, where syn-kinematic deposits of Late Weichselian age (MIS2) accumulated in a piggyback basin. Sedimentological analyses, including micromorphology and field studies, resulted in a distinction of at least five tectono-depositional sequences of syn-glacitectonic basin fills. The sediment record indicates a stepwise evolution of the basin, controlled by propagating thrust faults and the resulting thrust-bound ridge morphology. A fast-changing depositional environment with glacifluvial, glacilacustrine, alluvial fan and fan delta depositional systems, show a rapid transformation of the overall morphology of the study area. The main controlling factors are the propagating thrust faults (determining anticline and syncline orientations) and the advancing ice margin, which caused sudden changes or even temporal obstruction of the meltwater drainage system. The proposed stages of basin evolution illustrate the dynamic formation and stepwise syn-tectonic fill of piggyback basins in glacitectonic complexes. Our evolutionary model will increase our understanding of basin fills on glacitectonic thrust- and fold-belts that were formed by approaching ice sheets in ice-marginal settings. [ABSTRACT FROM AUTHOR]

In this paper we present a new fast and deterministic algorithm for the inverse discrete cosine transform of type II for reconstructing a real input vector of length N with short support of length m from its discrete cosine transform of type II if an upper bound M on the support length m is known. The resulting algorithm only uses real arithmetic, has a sublinear runtime of O (M log ⁡ M + m log 2 ⁡ N M) and requires O (M + m log 2 ⁡ N M) samples. For m and M approaching the vector length, the runtime and sampling requirements approach those of a regular IDCT-II for vectors with full support. [ABSTRACT FROM AUTHOR]

The Bermejo retroarc foreland basin system formed in flexural response to Cenozoic crustal thickening in the Andean orogenic system, specifically, the eastward propagation of the Precordillera fold-thrust belt and the basement-involved uplift of the Sierras Pampeanas. Previous work in the region has mainly focused on the mechanisms and expression of flat slab subduction and the structural geometry of the basement-involved Sierras Pampeanas and east-directed Precordillera fold-thrust belt at depth, advancing our understanding of the Bermejo basin history north of 31°S. However, the along strike evolution of the basin system to the south remains unresolved and contrasting tectonic models have proposed the Bermejo basin evolved synchronously versus asynchronously through time. Our study seeks to constrain the along-strike Neogene tectonics of the Bermejo basin via well-exposed Miocene fluvial stratigraphic intervals along the Eastern Precordillera, integrated with detrital zircon U–Pb geochronology provenance and detrital apatite (U–Th)/He thermochronology datasets. New data from two Neogene stratigraphic sections in the southern Bermejo basin constrain deposition between 13 and 6 Ma. Dominant fluvial-lacustrine mudstones, siltstones, and sandstones transition into fluvial-megafan deposits capped by alluvial fan conglomerate facies, tracking the eastward migration of Precordillera deformation. The cessation of sedimentation, and thermal history models of apatite (U–Th-Sm)/He thermochronology ages, indicates basin incorporation into the orogenic wedge by 6 Ma. When we compare our southern datasets with previous constraints from the northern Bermejo basin, we observe, from north to south: (1) a time-transgressive trend in basin initiation, (2) a ∼3 km decrease in stratigraphic thicknesses, and (3) older exhumation along the thrust front. These trends highlight the asynchronous nature of the Bermejo foreland basin system and along-strike variability of Precordillera thrust-front evolution. • New measured stratigraphic sections from the southern Bermejo basin are compared against localities along-strike • Detrital zircon U–Pb ages constrain deposition between 13 and 6 Ma, and record erosion of Andean source regions • Detrital apatite He dates track basin burial reheating, and cooling during exhumation of the Eastern Precordillera • Time-transgressive trend in exhumation along strike of the Bermejo basin implies diachronous deformation of basin deposits [ABSTRACT FROM AUTHOR]

In this paper we propose a new fast Fourier transform to recover a real non-negative signal x ∈ R + N from its discrete Fourier transform x ̂ = F N x ∈ C N . If the signal x appears to have a short support, i.e., vanishes outside a support interval of length m < N , then the algorithm has an arithmetical complexity of only O ( m log m log ( N / m ) ) and requires O ( m log ( N / m ) ) Fourier samples for this computation. In contrast to other approaches there is no a priori knowledge needed about sparsity or support bounds for the vector x . The algorithm automatically recognizes and exploits a possible short support of the vector and falls back to a usual radix-2 FFT algorithm if x has (almost) full support. The numerical stability of the proposed algorithm is shown by numerical examples. [ABSTRACT FROM AUTHOR]

We derive new explicit expressions for the components of Moore–Penrose inverses of symmetric difference matrices. These generalized inverses are applied in a new regularization approach for scattered data interpolation based on partial differential equations. The columns of the Moore–Penrose inverse then serve as elements of a dictionary that allow a sparse signal approximation. In order to find a set of suitable data points for signal representation we apply the orthogonal matching pursuit (OMP) method. [ABSTRACT FROM AUTHOR]

In this paper, we want to reconstruct polygonal shapes in the real plane from as few Fourier samples as possible, that is, we want to recover an original polygonal domain D with N vertices by using sparse sampling values of the Fourier transform of the characteristic function of the polygonal domain. We consider only simply-connected polygons, i.e. polygons with non-intersecting edges. For this purpose, we need to reconstruct the vertices of the polygon. In the case of non-convex polygons, we also need to reconstruct the order of the vertices to determine the correct boundary line segments. The method presented here is based on the Prony method. [ABSTRACT FROM AUTHOR]

More than 650 subsurface concave structures (1–20 m long, 0.5–7 m wide, and 0.1–0.9 m deep) were described in soils developed of clays overlain by loess in a large-scale archeological excavation in SW Poland. The structures are considered to be microlows and microhighs similar to those in gilgaied vertisols, which have never been reported in Central Europe until now. Soils do not have a clayey texture throughout the profile; however, the thick and humus-rich mollic horizons, as well as a clay-enriched argic layers, developed directly above vertic horizons have favored soil cracking and shrink–swell phenomena in the clayey subsoil. As a result, well developed wedge-shaped (lenticular) aggregates have formed in the clayey subsoil. Aggregates have grooved surfaces with an oriented matrix (slickensides) and are ordered under variable angles from 10 to 60°. A periglacial origin of these structures has been rejected and the mid- to late-Holocene period (since the Neolithic epoch) has been considered to be favorable for intense shrink–swell phenomena, vertic horizon development and clayey mass cycling responsible for the subsurface bowl and chimney structure development. A micro-mosaic of soil units related to these structures has been distinguished, including (non- or deep-vertic) Stagnic Chernozems/Phaeozems above the microlow centers, Mollic Planosols (Vertic) above the microslopes, and Mollic Planosols (Protovertic) over the microhighs (chimneys). It is concluded that a temperate climate (as in Central Europe) allows the formation of vertic properties and subsurface mass reorganization similar to those in soils with gilgai microrelief, if specific conditions – clayey substratum, position in landscape, soil moisture regime and the land use connected with vegetation type – support deep seasonal changes of soil moisture and shrink–swell phenomena in the subsoil. [ABSTRACT FROM AUTHOR]