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Knowledge about the initial tectonic and depositional dynamics, as well as the influence of early rifting on climate and environmental evolution remains speculative to a large extent, because sediments are usually deeply buried. Within the East African Rift System, inversion tectonics uplifted a few of these successions to the surface hence presenting rare windows into the pre‐rift depositional history. One such example, an exceptional 700 m long and up to 60 m high fresh road cut provided the opportunity to study in detail initial rift successions of the southern Albertine Rift (Western Uganda). This focusses on the basal and poorly known Middle to Late Miocene in order to unravel the climatic, environmental, hydrological and tectonic evolution of the initial Albertine Rift. A large and robust multi‐proxy dataset was gathered comprising 169 m of stratigraphic thickness, which spans from 14.5 to 4.9 Ma according to a revised lithostratigraphic model. Fieldwork comprised logging of the sedimentary record, spectral gamma ray, magnetic susceptibility and 2D wall mapping with photomosaics. Additionally, the sections were sampled for bulk mineral and clay mineral analysis. The succession exposes a suite of lithofacies and architectural elements detailing the evolution of a fluvio‐lacustrine system. Five depositional environments were identified which show an overall back‐stepping trend from an alluvial plain to a delta plain and finally palustrine/shallow lacustrine conditions. Mesoscale base‐level cycles, preservation potential of architectural elements, and stacking pattern exhibit limited accommodation space. However, it increases over time. This overall trend indicates increasing tectonic subsidence, which can be explained by flexural downwarp within the pre‐rift phase and in the upper part grading into fault‐controlled crustal extension of the syn‐rift phase, which more and more disrupted a large‐scale river system. From the Middle Miocene up to the early Pliocene, this study revealed that palaeoclimate trends become marked by increasing and more fluctuating Th concentrations, loss of feldspar, intercalated lenses of hydroxosulphate minerals, and a shift from smectite‐dominated to kaolinite‐dominated clays. These signals are all interpreted as detrital except for the hydroxosulphates, and they mirror the increasing intensity of chemical weathering and stripping of soils in the catchment. A trend towards increasing humidity is supported by an increase in lacustrine sediment facies and a lake‐level rise. Nevertheless, intercalation of hydroxosulphate, ferricretes and pedogenised horizons prove ongoing seasonality and dry intervals. Finally, based on a revised stratigraphic model a sequence stratigraphic correlation of the outcrop's depositional cycles with basin‐scale cycles is presented. According to these cycles, transition from the pre‐rift to the syn‐rift stage is marked by an unconformity and a tectonic pulse in the latest Miocene. However, the response of fluvial supply, the depositional system as well as climate conditions are less punctuated and characterised by gradual trends and temporal delays. The long pre‐rift phase (ca 10 Myr) and the gradual transition to the syn‐rift phase is in accordance with the active rifting model, which is based on thermal thinning of the lithosphere by asthenospheric upwelling. This study investigates the depositional record of the Albert Rift within the East African Rift System. Climatic and tectonic signals have been extracted from petrophysical data and sedimentary environments. These multi‐proxy data were successfully correlated with a basin wide sequence stratigraphic framework revealing tectonic and climatic controls of deposition.

Weathering is a basic geological process that refers to the breaking down or dissolving of rocks and minerals on the surface of the earth. However, weathering characteristics may vary among different lithologies even under similar conditions. To evaluate and quantitatively compare the physical and chemical index of alteration among different types of rock, new concepts of paleo-weathering such as the absolute weathering degree and the relative weathering degree are proposed for microscale studies. For the quantification of physical weathering, the index of physical weathering (IPW) is introduced. The index is defined as the ratio between the area of the fractures formed during different weathering stages and the total area of the thin section under the polarizing microscope and it is corrected by the corresponding rock strength. To quantitatively compare the chemical weathering intensity among different types of rock and minerals, the following two new concepts are introduced: total weathering mass (TWM) and chemical weathering ability (CWA). While the TWM is an integral function of weathering rate and weathering time for minerals, the CWA is the sum of the TWM of each mineral in rock within a certain time period. As a case study, this concept is applied to the weathered crystalline basement below the post-Variscan nonconformity in southwestern Germany. The petrography and geochemistry of three drillings penetrating the nonconformity were investigated by polarizing microscopy, X-ray diffractometry (XRD), scanning electron microscope (SEM), X-ray fluorescence (XRF) and inductively coupled plasma-mass spectrometry (ICP-MS). The investigations illustrate how to better extract quantitative information for both, physical and chemical weathering.

Alluvial fans record climate-driven erosion and sediment-transport processes and allow reconstructing past environmental conditions. Here we investigate the sedimentation history of two alluvial fans located in formerly glaciated valleys of the Cordillera Oriental, Peru. 10Be exposure ages from the fan surfaces and radiocarbon ages from the fan interiors constrain the final stages of fan formation. The 10Be and 14C ages cluster mainly between 13.3–9.3 ka and 11,500–9700 cal yr BP, respectively. Our age data set indicates that—after deglaciation—large amounts of fan sediment were deposited until ∼10 ka, when sedimentation rates declined rather abruptly. This pattern is supported by 10Be erosion rates for the fan catchments, because under the assumption of constant erosion the time needed to erode the material stored in the fans significantly exceeds their age. Correlating our ages with regional climate records indicates that precipitation exerts the primary control on fan sedimentation. Two periods with elevated lake levels and increased precipitation between 18 and 14.5 ka and from 13 to 11.5 ka resulted in rapid deposition of large fan lobes. Subsequently, lower precipitation rates decreased erosion in the catchments and sediment delivery to the fans, which have remained largely inactive since ∼9.5 ka.

A recent bathymetric survey of Lake Constance revealed ~ 170 mounds composed of loosely deposited rocks aligned in a ~ 10-km long chain along the southern Swiss shoreline in a water depth of 3–5 m. The mounds are 10–30 m in diameter and up to 1.5 m high. Over their entire length of occurrence, the mounds are estimated to be composed of ~ 60 million individual boulders, with a total weight of ~ 78,000 t. A ground penetrating radar (GPR) survey showed that the mounds are not linked to the glacial substrate but were rather deposited artificially on the edge of a prograding shelf composed of Holocene lake sediments. Here, we present the results of a coring campaign with four piston cores along a GPR transect across one of the mounds. The cores recovered the full Holocene sedimentary succession all the way into the basal till that is overlain by lacustrine sediments dating back to ~ 14,400 cal. yrs BP. The four cores are merged into a ~ 12.4-m long composite section reflecting continuous sedimentation from the siliciclastic-dominated Late Glacial to the carbonate-rich Late Holocene. The stratigraphic horizon representing the mound’s construction was radiocarbon-dated to ~ 5600–5300 cal. yrs BP, placing them in the Neolithic period. This age was confirmed by radiocarbon dating of wood samples collected during underwater excavation of the mounds. Geochemical analysis of the Holocene sedimentary succession shows generally high carbonate contents (average of 69%). The interval from 5750 to 4950 cal. yrs BP, a part of the mound period, is characterized by a Holocene minimum in carbonate content (average of 57%) and by larger mean grain sizes. Comparing these values to those from a recent surface-sediment depth transect indicates that this was a period of rather low lake levels, which might have favoured mound construction. Correlations to nearby archaeological sites and to the general West-Central European lake-level record indicates that the mounds likely were built during a short phase of low lake levels during a general trend of climatic cooling followed by a lake-level transgression.

The prediction of physicochemical rock properties in subsurface models regularly suffers from uncertainty observed at the submeter scale. Although at this scale – which is commonly termed the lithofacies scale – the physicochemical variability plays a critical role for various types of subsurface utilization, its dependence on syndepositional and postdepositional processes is still subject to investigation. The impact of syndepositional and postdepositional geological processes, including depositional dynamics, diagenetic compaction and chemical mass transfer, onto the spatial distribution of physicochemical properties in siliciclastic media at the lithofacies scale is investigated in this study. We propose a new workflow using two cubic rock samples where eight representative geochemical, thermophysical, elastic and hydraulic properties are measured on the cubes' faces and on samples taken from the inside. The scalar fields of the properties are then constructed by means of spatial interpolation. The rock cubes represent the structurally most homogeneous and most heterogeneous lithofacies types observed in a Permian lacustrine-deltaic formation that deposited in an intermontane basin. The spatiotemporal controlling factors are identified by exploratory data analysis and geostatistical modeling in combination with thin section and environmental scanning electron microscopy analyses. Sedimentary structures are well preserved in the spatial patterns of the negatively correlated permeability and mass fraction of Fe2O3. The Fe-rich mud fraction, which builds large amounts of the intergranular rock matrix and of the pseudomatrix, has a degrading effect on the hydraulic properties. This relationship is underlined by a zonal anisotropy that is connected to the observed stratification. Feldspar alteration produced secondary pore space that is filled with authigenic products, including illite, kaolinite and opaque phases. The local enrichment of clay minerals implies a nonpervasive alteration process that is expressed by the network-like spatial patterns of the positively correlated mass fractions of Al2O3 and K2O. Those patterns are spatially decoupled from primary sedimentary structures. The elastic properties, namely P-wave and S-wave velocity, indicate a weak anisotropy that is not strictly perpendicularly oriented to the sedimentary structures. The multifarious patterns observed in this study emphasize the importance of high-resolution sampling in order to properly model the variability present in a lithofacies-scale system. Following this, the physicochemical variability observed at the lithofacies scale might nearly cover the global variability in a formation. Hence, if the local variability is not considered in full-field projects – where the sampling density is usually low – statistical correlations and, thus, conclusions about causal relationships among physicochemical properties might be feigned inadvertently.

The volcaniclastic Tepoztlán Formation (TF) represents an important rock record to unravel the early evolution of the Transmexican Volcanic Belt (TMVB). Here, a depositional model together with a chronostratigraphy of this Formation is presented, based on detailed field observations together with new geochronological, paleomagnetic, and petrological data. The TF consists predominantly of deposits from pyroclastic density currents and extensive epiclastic products such as tuffaceous sandstones, conglomerates and breccias, originating from fluvial and mass flow processes, respectively. Within these sediments fall deposits and lavas are sparsely intercalated. The clastic material is almost exclusively of volcanic origin, ranging in composition from andesite to rhyolite. Thick gravity-driven deposits and large-scale alluvial fan environments document the buildup of steep volcanic edifices. K-Ar and Ar-Ar dates, in addition to eight magnetostratigraphic sections and lithological correlations served to construct a chronostratigraphy for the entire Tepoztlán Formation. Correlation of the 577 m composite magnetostratigraphic section with the Cande and Kent (1995) Geomagnetic Polarity Time Scale (GPTS) suggests that this section represents the time intervall 22.8–18.8 Ma (6Bn.1n-5Er; Aquitanian-Burdigalian, Lower Miocene). This correlation implies a deposition of the TF predating the extensive effusive activity in the TMVB at 12 Ma and is therefore interpreted to represent its initial phase with predominantly explosive activity. Additionally, three subdivisions of the TF were established, according to the dominant mode of deposition: (1) the fluvial dominated Malinalco Member (22.8–22.2 Ma), (2) the volcanic dominated San Andrés Member (22.2–21.3 Ma) and (3) the mass flow dominated Tepozteco Member (21.3–18.8 Ma).

Sandstones are often characterized as fractured aquifers. We present a case study of the Wajid sandstone, which forms a regional aquifer system in SW Saudi Arabia, where matrix, fracture, and large-scale hydraulic conductivities are coincident. The measurements deal with different scales and methods and are based on porosity and permeability measurements in the laboratory, as well as pumping tests in the field. Porosities of the sandstone samples in general are high and range between less than 5 % and more than 45 %. Gas permeabilities for strongly cemented samples are < 1 mD, whereas most samples range in between 500 and 5,000 mD. There is only a weak anisotropy with preference of the horizontal x-, y-directions. Hydraulic conductivities of the matrix samples (5.5 · 10 −6  m/s and 1.1 · 10 −5  m/s for the Upper and Lower Wajid sandstone, respectively) were in the same order of magnitude compared to hydraulic conductivities derived from pumping tests (8.3 · 10 −5  m/s and 2.2 · 10 −5  m/s for the Upper and Lower Wajid sandstone, respectively).

Sandstones are often characterized as fractured aquifers. We present a case study of the Wajid sandstone, which forms a regional aquifer system in SW Saudi Arabia, where matrix, fracture, and large-scale hydraulic conductivities are coincident. The measurements deal with different scales and methods and are based on porosity and permeability measurements in the laboratory, as well as pumping tests in the field. Porosities of the sandstone samples in general are high and range between less than 5 % and more than 45 %. Gas permeabilities for strongly cemented samples are < 1 mD, whereas most samples range in between 500 and 5,000 mD. There is only a weak anisotropy with preference of the horizontal x-, y-directions. Hydraulic conductivities of the matrix samples (5.5 · 10⁻⁶ m/s and 1.1 · 10⁻⁵ m/s for the Upper and Lower Wajid sandstone, respectively) were in the same order of magnitude compared to hydraulic conductivities derived from pumping tests (8.3 · 10⁻⁵ m/s and 2.2 · 10⁻⁵ m/s for the Upper and Lower Wajid sandstone, respectively).

Malnutrition is known to independently affect patient outcomes. The aim of this study was to investigate the prevalence of patients at risk for malnutrition in an elective surgery patient cohort and to analyze the effects of malnutrition on morbidity, mortality, and hospital length of hospital (LOS). Furthermore, we aimed to evaluate the economic effect of a diligent coding of malnutrition, as a side diagnosis, in a simulation of the German Diagnosis-Related Group system. The nutritional status of 1244 patients undergoing elective surgery was standardized on the day of admission by the Nutritional Risk Screening (NRS) 2002. To quantify the influence of malnutrition on revenue, the real DRGs of all patients were grouped. In simulation, an appropriate International Classification of Diseases code was used as a secondary diagnosis for all malnourished patients based on the NRS rating. A multivariate logistic regression analysis and a Cox regression were performed to identify potential confounders and to determine the adjusted effect of nutritional status on the occurrence of complications and hospital LOS. The prevalence of patients at risk for malnutrition (NRS ≥3) was 24.1% (300 of 1244). These patients showed a significant increase in hospital LOS (13 versus 7 d). Additionally, postoperative complications were significantly higher in this group (7.23% versus 6.91%). Including malnutrition in the Diagnosis-Related Group coding system resulted in a reimbursement of €1979.67 per patient at risk for malnutrition and a total reimbursement of €79,186.73 for all patients at risk for malnutrition in the present study. Establishment of a structured, comprehensive assessment of the nutritional status of hospitalized patients can repetitiously identify patients at risk for malnutrition. Additionally, the diligent codification of malnutrition can lead to cost compensation in the German Diagnosis-Related Group system.

The mammalian brain cortex is highly folded, with several developmental disorders affecting folding. On the extremes, lissencephaly, a lack of folds in humans, and polymicrogyria, an overly folded brain, can lead to severe mental retardation, short life expectancy, epileptic seizures, and tetraplegia. Not only a specific degree of folding, but also stereotyped patterns, are required for normal brain function. A quantitative model on how and why these folds appear during the development of the brain is the first step in understanding the cause of these conditions. In recent years, there have been various attempts to understand and model the mechanisms of brain folding. Previous works have shown that mechanical instabilities play a crucial role in the formation of brain folds, and that the geometry of the fetal brain is one of the main factors in dictating its folding characteristics. However, modeling higher-order folding, one of the main characteristics of the highly gyrencephalic brain, has not been fully tackled. The simulations presented in this work are used to study the effects of thickness inhomogeneity in the gyrogenesis of the mammalian brain in silico. Finite-element simulations of rectangular slabs are performed. These slabs are divided into two distinct regions, where the outer region mimicks the gray matter, and the inner region the underlying white matter. Differential growth is introduced by growing the top region tangentially, while keeping the underlying region untouched. The brain tissue is modeled as a neo-Hookean hyperelastic material. Simulations are performed with both homogeneous and inhomogeneous cortical thicknesses. Our results show that the homogeneous cortex folds into a single wavelength, as is common for bilayered materials, while the inhomogeneous cortex folds into more complex conformations. In the early stages of development of the inhomogeneous cortex, structures reminiscent of the deep sulci in the brain are obtained. As the cortex continues to develop, secondary undulations, which are shallower and more variable than the structures obtained in earlier gyrification stage emerge, reproducing well-known characteristics of higher-order folding in the mammalian, and particularly the human, brain.