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In this paper, the numerical properties of a recently developed high‐order Spectral Euler‐Bernoulli Beam Element (SBE) featuring a C¹‐continuous approximation of the displacement field are assessed. The C¹‐continuous shape functions are based on two main ingredients, which are an Hermitian interpolation scheme and the use of Gauß‐Lobatto‐Legendre (GLL) points. Employing GLL‐points does not only avoid Runge oscillations, but also yields a diagonal mass matrix when exploiting the nodal quadrature technique as a mass lumping scheme. Especially in high‐frequency transient analyses, where often explicit time integration schemes are utilized, having a diagonal mass matrix is an attractive property of the proposed element formulation. This is, however, achieved at the cost of an under‐integration of the mass matrix. Therefore, a special focus of this paper is placed on the evaluation of the numerical properties, such as the conditioning of the element matrices and the attainable rates of convergence (ROCs). To this end, the numerical behavior of the SBEs is comprehensively analyzed by means of selected benchmark examples. In a nutshell, the obtained results demonstrate that the element yields good accuracy in combination with an increased efficiency for structural dynamics exploiting the diagonal structure of the mass matrix.

The spatial and temporal distribution of Alpine snow is a sensitive gauge of environmental change. While understanding past snow dynamics is essential for reconstructing past climate and forecasting future trends, reliable snowpack data prior to the instrumental record are scarce. We present a novel pairing of cosmogenic paleothermometry and luminescence photochronometry which constrain the temperature and insolation history of bedrock outcrops at the Gotthard Pass, Switzerland, over the last ∼15,000 years. By coupling these results with cosmogenic 14C-10Be chronology and modern in situ rock thermometry, we infer a ∼70-day reduction of snowpack at the topographic mid-slope. Our data indicate stable environmental conditions throughout the Holocene, followed by a 6.6 ± 2.9°C increase of ground surface temperature, coeval with an order-of-magnitude or more increase in ground surface insolation. Bracketing the onset of these changes between 1504 and 1807 CE, our findings tie the snowpack decline with the onset of human industrialization.

Wind-abraded cobbles (ventifacts) and aeolian sand are known from the sandy-gravelly coastal areas of south-western Sweden, especially in association with raised deltas. Ventifacts are recorded on at least two different stratigraphic levels, on top of glaciofluvial sediment and/or on top of littoral deposits, while aeolian sand usually forms a surficial cover. The formation of ventifacts has usually been coupled to abrasion due to katabatic winds from the retreating ice sheet or with periglacial climate during the Younger Dryas stadial (12.8-11.6 ka). However, there are very few absolute ages, and the timing of wind deflation has recently been challenged and proposed to be much older (110-70 ka). To determine the timing of these deflation events, we have applied a combination of dating methods to ventifacts and associated sediments on top of an ice-contact delta at Veinge, south-western Sweden. Quartz and feldspar luminescence dating as well as portable luminescence profiling has been used for the over- and underlying sediments, while rock surface luminescence burial dating and paired 14C10Be cosmogenic nuclide dating were done on ventifacts. The results show that a first deflation event occurred c. 16.5 ka, just after deglaciation and prior to a regional transgression that peaked around 15.7 ka. At 12.4-11.4 ka, during and just after the Younger Dryas stadial, a new set of ventifacts formed on the surface of the exposed littoral sands and gravels. Some wind abrasion also occurred in the early Holocene, but at c. 8.5 ka the surface was covered by aeolian sand, up to 2.5 m thick. The combination of dating methods allowed us to extract more information about the timing and duration of these wind abrasion/transport events than we would have if only a single method had been used, and it is also possible to infer some environmental conditions. For example, both glaciofluvial and littoral deposits show evidence of incomplete bleaching of the luminescence signal. This sugg

Recent suggestions propose that the glacial landscape of southern Sweden is a relict landscape from the Saalian glaciation (>130 ka) (Lagerbäck, 2018). The primary argument supporting this viewpoint is the claimed observation that the majority of glaciofluvial deposits in this region exhibits a covering till bed, often accompanied by wind-abraded clasts (ventifacts) at the contact between glaciofluvial sediment and till. It has been further posited that this wind abrasion event dates back to the Early Weichselian, preceding the last glaciation, and occurred during periglacial conditions of that period. If this were indeed the case, it would imply that generations of Quaternary geologists had overlooked or disregarded this relationship, necessitating a paradigm shift in our comprehension of the Quaternary geological history of the area.To assess the validity of these claims, we conducted a comprehensive evaluation of purported stratigraphic conditions within 54 gravel quarries south of the Middle Swedish End Moraine Zone (MSEMZ). The presence of a covering bed of what can be sedimentologically interpreted as a glacially deposited diamict  a till  above glaciofluvial sediments was confirmed in only 22% of the gravel pits. These occurrences were primarily linked to locations in close proximity to well-known positions associated with ice-margin standstills or oscillations during the Late Weichselian. In all other quarries, where the presence of covering till could not be confirmed, ventifacts were found in various stratigraphic positions. These positions were contingent upon deglacial and post-deglacial environmental conditions and included ventifacts at the contact between glaciofluvial and overlying littoral sediment, ventifacts redeposited within littoral sediment, and ventifacts at the contact between glaciofluvial or littoral sediment and overlying aeolian sediment.To ascertain the age of the ventifaction event(s), we conducted an extensive luminescence (OSL) dat

The dating of moraine deposits can present challenges to standard geochronological methods; terrestrial cosmogenic nuclide (TCN), sediment luminescence and radiocarbon dating may suffer from problems of incomplete resetting (by inheritance, intermittent cover/exposure, transport under unfavourable conditions) and/or a lack of suitable (organic) material. Rock surface luminescence burial dating (RSLBD) offers an alternative approach with considerable potential in dating moraines. In RSLBD, large cobbles/boulders are targeted, rather than smaller grains usually used in luminescence dating. The age limit of RSLBD is much higher than that of radiocarbon dating, and rocks are much more readily available than organic material. In contrast to TCN dating, the effect of exposure prior to deposition can be measured. In this study, we sampled a broad selection of primarily granitic boulders of various sizes and shapes (e.g. different degrees of roundness and sphericity) from the Vimmerby Moraine, a prominent and accessible feature in southern Sweden dated using TCN to 14.4±0.9 ka. Our study was designed to test whether morphological characteristics can be used to discriminate in favour of the most light-exposed boulders and minimize measurements of non-exposed boulders. As expected, not all RSLBD ages can be attributed to the same depositional event, but the majority of the resulting ages provide a mean age of 13.0±1.5 ka, consistent with the cosmogenic nuclide dating of the Vimmerby Moraine. Despite the apparently successful TCN study, the luminescence–depth profiles measured in the buried surfaces of the sampled clasts indicate that >50% of these moraine boulders were exposed to light (and cosmic radiation) before final deposition, implying some (presumably small) TCN inheritance; seven of the 16 boulders identified as light exposed were sufficiently bleached to be useful for RSLBD. These results and their implications in regard to transport and deposition of the sampl