Prehistoric and recent mass movements of the World Cultural Heritage Site Hallstatt, Austria

Hallstatt Village, located in the Austrian Alps, is designated by the United Nations Educational, Scientific and Cultural Organization as part of the World Cultural Heritage Site Hallstatt–Dachstein. This region is recognized for its salt deposits that have been exploited since the Neolithic period. In former times, these salt deposits were very rare and precious. Due to unfortunate bedding conditions, mass movements have been frequent in the past and continue to affect the site today. These active and inactive mass movements were mapped geotechnically to a scale of 1:5,000 and the mineralogical and mechanical properties of the main instable soft rocks were investigated. Rock spreads, rock slides, rock falls, rock topples, earth flows and earth and debris slides are the primary types of mass movements recorded. They are most frequently observed in areas affected by mining, though they may also occur in areas where no anthropogenic influence is recognized. Evidence exists in the archaeological record that indicates prehistoric mining activities were also seriously affected by the impact of mass movements.     

Pre-Variscan geological events in the Austrian part of the Bohemian Massif deduced from U–Pb zircon ages

In an attempt to elucidate the pre-Variscan evolution history of the various geological units in the Austrian part of the Bohemian Massif, we have analysed zircons from 12 rocks (mainly orthogneisses) by means of SHRIMP, conventional multi-grain and single-grain U–Pb isotope-dilution/mass-spectrometry. Two of the orthogneisses studied represent Cadomian metagranitoids that formed at ca. 610 Ma (Spitz gneiss) and ca. 580 Ma (Bittesch gneiss). A metagranite from the Thaya batholith also gave a Cadomian zircon age (567±5 Ma). Traces of Neoproterozoic zircon growth were also identified in several other samples, underlining the great importance of the Cadomian orogeny for the evolution of crust in the southern Bohemian Massif. However, important magmatic events also occurred in the Early Palaeozoic. A sample of the Gföhl gneiss was recognised as a 488±6 Ma-old granite. A tonalite gneiss from the realm of the South Bohemian batholith was dated at 456±3 Ma, and zircon cores in a Moldanubian metagranitic granulite gave similar ages of 440–450 Ma. This Ordovician phase of magmatism in the Moldanubian unit is tentatively interpreted as related to the rifting and drift of South Armorica from the African Gondwana margin. The oldest inherited zircons, in a migmatite from the South Bohemian batholith, yielded an age of ca. 2.6 Ga, and many zircon cores in both Moravian and Moldanubian meta-granitoid rocks gave ages around 2.0 Ga. However, rocks from the Moldanubian unit show a striking lack of zircon ages between 1.8 and 1.0 Ga, reflecting an ancestry from Armorica and the North African part of Gondwana, respectively, whereas the Moravian Bittesch gneiss contains many inherited zircons with Mesoproterozoic and Early Palaeoproterozoic ages of ca. 1.2, 1.5 and 1.65–1.8 Ga, indicating a derivation from the South American part of Gondwana.     

Geostatistical mapping of real estate prices: an empirical comparison of kriging and cokriging

Small-sized housing samples and price predictions at nonobserved locations require geostatistical approaches, particularly the kriging estimator. Nevertheless, geostatistics has thus far received little attention in real estate economics. The article’s objective is to empirically compare the prediction accuracy of univariate kriging variants, namely detrended kriging (DK) and universal kriging (UK), and multivariate extensions, including detrended cokriging (DCK) and universal cokriging (UCK). Both latter methods consider structural and neighborhood characteristics as auxiliary variables. While the price surfaces of DK and UK show nearly identical cross-validated accuracies, the cross-validation-based prediction accuracy of DCK and UCK differ in favor of the latter. If real estate agencies are faced with a univariate sample of property prices, either DK or UK can be used, while in the multivariate case, UCK is recommended, although numerically more complex.     

Dependence between flood peaks and volumes: a case study on climate and hydrological controls

Abstract

The aim of this paper is to understand the causal factors controlling the relationship between flood peaks and volumes in a regional context. A case study is performed based on 330 catchments in Austria ranging from 6 to 500 km² in size. Maximum annual flood discharges are compared with the associated flood volumes, and the consistency of the peak–volume relationship is quantified by the Spearman rank correlation coefficient. The results indicate that climate-related factors are more important than catchment-related factors in controlling the consistency. Spearman rank correlation coefficients typically range from about 0.2 in the high alpine catchments to about 0.8 in the lowlands. The weak dependence in the high alpine catchments is due to the mix of flood types, including long-duration snowmelt, synoptic floods and flash floods. In the lowlands, the flood durations vary less in a given catchment which is related to the filtering of the distribution of all storms by the catchment response time to produce the distribution of flood producing storms.

Editor Z.W. Kundzewicz     

Comparative analysis of the seasonality of hydrological characteristics in Slovakia and Austria / Analyse comparative de la saisonnalité de caractéristiques hydrologiques en Slovaquie et en Autriche

Abstract

The main objective of this study is to compare the seasonality of selected precipitation and runoff characteristics in Austria and Slovakia. Monthly seasonality indices are analysed to interpret the long-term climatic behaviour, while the seasonality of extremes is analysed to understand flood occurrence. The analysis is based on mean monthly precipitation data at 555 (Austria) and 202 (Slovakia) stations, annual maximum daily precipitation at 520 (Austria) and 56 (Slovakia) stations, and mean monthly runoff and annual maximum floods at 258 (Austria) and 85 (Slovakia) gauging stations. The results suggest that the seasonality of the selected hydrological characteristics is an important indicator of flood processes, but varies considerably in space. The seasonality of extreme flood events and, hence flood processes, tends to change with the flood magnitude. This change is more pronounced in the lowland and hilly regions than it is in the mountains. Both in Austria and Slovakia, decades of flood seasonality exist.     

奥地利Gosau群Bibereck组Campanian早期早期海水变深序列的地层学和地球化学

Schmidsippl剖面位于奥地利北钙质阿尔卑斯构造带内Gosau群典型地区。剖面出露的Bibereck组记录了一个海侵和沉积区海水变深过程。Bibereck组之下是Santonian晚期Hoclamoos组(Santlkalkbank段)，主要为砂质、粉砂质灰色生物扰动构造发育的泥灰岩，含少量双壳类碎片。Hochmoos组之上为灰色泥灰岩和泥灰质灰岩。Bibereck组下部显示变深到近滨-远滨过渡带区域；向上，泥灰岩指示细粒泥质远滨沉积，水深大致50～150m；之上出现浮游有孔虫含量超过90％的泥灰质灰岩，代表着半深海沉积环境。生物地层数据显示采样层位整体位于浮游有孔虫asymetrica-elevata带，由Globotruncanita elevata和Dicarinella asymetrica的共同出现来界定。钙质超微化石Calculites obscurus、Lucianorhabdus cayeuxii、Arkhangelskiella cymbi formis的出现指示属于钙质超微化石带CC17b／UC12，相当于Campanian初期。地层深度剖面上，Ca／Al比值和Catot含量显示海水来源的Ca在0～5m地层内几近于零，向上快速增加；(Fe／Al)／碳酸盐显示两个峰值，代表更还原条件，分别位于4m和10m位置；K／Al比值的下降被解释为更潮湿气候条件；剖面上部Ba含量的增加显示向更低原始生产条件的变化；陆源矿物在剖面7m以下保持稳定，之上一直到剖面顶部不断下降。生物地层数据表明在约50万年短暂的时间间隔内水深由几米深浅水环境变深为800～1500m深半深海环境。地球化学数据显示在海侵过程中出现两个海平面变化波动过程。这些数据为与上覆大洋红层进行对比提供了基础。