Refine
Year of publication
- 2022 (201) (remove)
Document Type
- Article (167)
- Doctoral Thesis (19)
- Postprint (10)
- Monograph/Edited Volume (2)
- Part of a Book (1)
- Other (1)
- Review (1)
Language
- English (201) (remove)
Is part of the Bibliography
- yes (201)
Keywords
- permafrost (7)
- climate change (6)
- Andes (3)
- diffusion (3)
- machine learning (3)
- ocean color remote sensing (3)
- pollen (3)
- radiation belts (3)
- stable isotopes (3)
- Arctic ocean (2)
- Argentina (2)
- Asia (2)
- Central Andes (2)
- Climate change (2)
- Diffusion (2)
- ERA5 (2)
- GEDI (2)
- ICESat-2 (2)
- Landsat (2)
- Magnetotellurics (2)
- Opalinus Clay (2)
- Opalinuston (2)
- PHREEQC (2)
- Precipitation (2)
- Sentinel 2 (2)
- Siberia (2)
- Tibetan Plateau (2)
- Vertical flux (2)
- analysis (2)
- bacteria (2)
- bat fatalities (2)
- biodiversity decline (2)
- canopy height (2)
- earthquake (2)
- extreme events (2)
- flood risk (2)
- floods (2)
- food web (2)
- geodynamics (2)
- green-green dilemma (2)
- hydraulic fracturing (2)
- isotopic fractionation (2)
- landscape evolution (2)
- lidar (2)
- mapping (2)
- modelling (2)
- monitoring (2)
- nearshore zone (2)
- numerical modelling (2)
- numerische Modellierung (2)
- radiocarbon (2)
- reactive transport (2)
- reaktiver Transport (2)
- renewable energy (2)
- savanna (2)
- seismic tomography (2)
- seismicity (2)
- sensitivity (2)
- subduction (2)
- surface processes (2)
- suspended sediment (2)
- wind energy production (2)
- %Ro (1)
- 16S rRNA genes (1)
- 2D Numerical Modelling (1)
- ASPECT (1)
- Active tectonics (1)
- Africa (1)
- Agricultural Model Inter-comparison and Improvement Project (AgMIP); (1)
- Air pollution (1)
- Alexander von Humboldt (1)
- Amazon region (1)
- Analog historical seismograms (1)
- Andean back-arc; (1)
- Anden (1)
- Antarctica (1)
- Arctic (1)
- Arctic Ocean (1)
- Arctic lakes (1)
- Arctic nearhore zone (1)
- Argentinien (1)
- Assapaat landslide (1)
- Atmospheric CO2 (1)
- B-isotopes (1)
- Baryt (1)
- Bayesian inference (1)
- Bayesian model (1)
- Beaufort Sea (1)
- Beni Suef Basin (1)
- Best management practice (1)
- Biodiversity (1)
- Blattverschiebung (1)
- Bocono (1)
- Body waves (1)
- Brazil (1)
- Bruchausbreitung (1)
- Building exposure modelling (1)
- CMIP6 (1)
- CO2 emissions (1)
- COH-fluid (1)
- CRNS (1)
- Carbonation (1)
- Causality (1)
- Cenozoic flat-slab (1)
- Central Myanmar Basin (1)
- Chain structure (1)
- Change-point regression model (1)
- Chilean Coastal Cordillera (1)
- Chilean subduction zone (1)
- Chironomidae (1)
- Cladocera (1)
- Climate (1)
- Climate governance (1)
- Climate reconstructions (1)
- Cluster analysis moment (1)
- Cologne (1)
- Colorado mineral belt (1)
- Comparative hydrology (1)
- Complex terrain (1)
- Composition and structure of the continental crust (1)
- Conductive channel (1)
- Continental Rifts (1)
- Coordination number (1)
- Cost-benefit (1)
- DEM analysis (1)
- DOC (1)
- Data collection (1)
- Data-Mining (1)
- Deep carbon cycle (1)
- Deformation (1)
- Deformationsmechanismen (1)
- Densification (1)
- Diamond anvil cell (1)
- Diatoms (1)
- Dissolved organic matter (DOM) (1)
- Distributed acoustic sensing (1)
- EMIC (1)
- EMIC waves (1)
- Early pleistocene; (1)
- Earthquake loss modelling (1)
- Earthquake scenario (1)
- Earthquake source observations (1)
- Earthquake swarm (1)
- East Asian summer monsoon (1)
- East Siberia (1)
- Eastern Alps (1)
- Eastern Dharwar craton (1)
- Egypt (1)
- El Nino Southern Oscillation (1)
- Electrical resistivity tomography (1)
- Embedding (1)
- Endlagerung nuklearer Abfälle (1)
- Engineering (1)
- Ensemble (1)
- Epistemic uncertainty (1)
- Erdbeben (1)
- Erosion (1)
- Ethiopia rift (1)
- Etna (1)
- European Alps (1)
- Evolutionary ecology (1)
- Extreme (1)
- Extremereignisse (1)
- Faceted taxonomy (1)
- Fagradalsfjall (1)
- FastScape (1)
- Field measurements (1)
- Fluid inclusion geochemistry (1)
- Fluid mixing (1)
- Fluid/magma reservoir (1)
- Focused ion beam (1)
- Forearc (1)
- Formationsschaden (1)
- Fourier analysis (1)
- Functional connectivity (1)
- GNSS (1)
- Ganga River (1)
- Garnet-orthopyroxene-cordierite gneiss (1)
- Gashydrate (1)
- Generalized Extreme Value distribution (1)
- Genetic algorithm (1)
- Geochronology (1)
- Geodynamic Modelling (1)
- Geodynamics (1)
- Geodynamik (1)
- Geodynamische Modellierung (1)
- Geomorphic systems (1)
- Geophysics (1)
- Geothermie (1)
- Germany (1)
- Gewässerfernerkundung (1)
- Ghana (1)
- Global inversion (1)
- Global warming (1)
- Global warming potential (1)
- Gorkha earthquake (1)
- Grabenbrüche (1)
- Granulite enclaves (1)
- Graph theory (1)
- Greek Islands (1)
- Greenhouse gas emissions (1)
- Ground-based estimates (1)
- Ground-motion model (1)
- Groundwater recharge (1)
- Grundgestein (1)
- Guaymas Basin (1)
- HBV-light model (1)
- HP-experiments (1)
- Hadley-Walker Circulation (1)
- Heteroscedastic (1)
- High pressure and high temperature; (1)
- Himalaya (1)
- Hochwasserrisiko (1)
- Homo sapiens (1)
- Horizontal (1)
- Horizontal flux (1)
- Hydrology (1)
- Hydrothermal veins (1)
- Iceland (1)
- Image processing (1)
- InSAR (1)
- India (1)
- Indian monsoon (1)
- Indian summer monsoon (1)
- Indo-Burman Ranges (1)
- Induzierte Seismizität (1)
- Injektion (1)
- Injektionsschema (1)
- Intermediate-deep earthquakes (1)
- International policy (1)
- Inverse methods (1)
- Ischigualasto-Villa Union Basin (1)
- Isotopenfraktionierung (1)
- James Ross archipelago (1)
- Joint Inversion (1)
- Kenya Rift (1)
- Kerogen petrography (1)
- L-moments estimation (1)
- LP (1)
- Lacustrine sediment (1)
- Lake Bosumtwi (1)
- Landscapes (1)
- Landslide chronosequences (1)
- Landslides (1)
- Las Chacras-Potrerillos (1)
- Late Glacial (1)
- Legume model (1)
- Limnology (1)
- Lithosphäre (1)
- Lokalisierung von Deformation (1)
- Low impact development (1)
- Lu-Hf (1)
- Machine learning (1)
- Magma-Entgasung (1)
- Magnitude scalin (1)
- Maldives carbonate platform (1)
- Mallik (1)
- Mediterranean (1)
- Merida Andes (1)
- Methane (1)
- Microbial processes (1)
- Micropollutants (1)
- Mikroplatte (1)
- Mikrostrukturelle (1)
- Model calibration (1)
- Model ensemble (1)
- Modellierung (1)
- Modellierung der Wassertrübung (1)
- Molybdenum mineralization (1)
- Mountain meteorology (1)
- Multivariate (1)
- N-butylpyridinium bromide (1)
- NSGA-II (1)
- Nano-XRF (1)
- NanoSIMS (1)
- NanoSIMS; (1)
- Nd isotopic composition (1)
- Near-source saturation (1)
- Near-surface geophysics (1)
- Neotektonik (1)
- Nepal (1)
- Nocardioides alcanivorans (1)
- Non-uniqueness (1)
- Northeast China (1)
- Northern Alpine Foreland Basin (1)
- Numerische 2D Modellierung (1)
- Nutrients (1)
- ODP 659 (1)
- ODP 721/722 (1)
- ODP 967 (1)
- Oberflächenprozesse (1)
- Ohre Rift (1)
- Okataina Caldera (1)
- OpenStreetMap (1)
- Optimization (1)
- Ore (1)
- Orinoco River system (1)
- PM balances (1)
- PM10, PM2, PM1 (1)
- PM10, PM2.5 and PM1.0 concentrations (1)
- PSD (1)
- Palaeoclimate (1)
- Paleoseismologie (1)
- Paläoklimatologie (1)
- Particle swarm optimization (1)
- Permafrostsedimente (1)
- Phytoliths (1)
- Phytoplankton (1)
- Plio-Pleistocene (1)
- Plio-pleistocene transition (1)
- Policy (1)
- Pollen (1)
- Prediction (1)
- Probabilistic exposure modelling (1)
- RCP4,5 and 8,5 (1)
- Raman spectroscopy (1)
- Raman-Spektroskopie (1)
- Random Forest (1)
- Reaktivierung von Störungszonen (1)
- Recharge controls (1)
- Recurrence analysis (1)
- Respiration (1)
- Reykjanes (1)
- Rhine basin (1)
- Rift (1)
- Risstransmissivität (1)
- Russia (1)
- Russian Arctic (1)
- SIMS (1)
- Salzgestein (1)
- Sava River (1)
- Scenario (1)
- Schadensmodellierung (1)
- Schallemissionen (1)
- Scheme (1)
- Sediment characterization (1)
- Sediment reuse (1)
- Seesystemreaktionen (1)
- Seismic anisotropy (1)
- Seismic damage assessment (1)
- Seismic nest (1)
- Seismic noise (1)
- Seismic risk (1)
- Seismic tomography (1)
- Seismicity and tectonics (1)
- Semiarid (1)
- Sensitivity analysis (1)
- Sentinel-1 InSAR (1)
- Short-lived climate pollutants (1)
- Sierra de San Luis (1)
- Silicate melts (1)
- Slope temperature (1)
- Sm-Nd (1)
- Soil (1)
- Sorption (1)
- South America (1)
- South China Sea (1)
- Spannungsmessung (1)
- Spatially cross-correlated ground motion (1)
- Spectral accelerations (1)
- Spectroscopy (1)
- State space reconstruction (1)
- Statistical analysis (1)
- StorAge Selection function (1)
- Storm water management model (1)
- Strain Localisation (1)
- Streamflow (1)
- Strike-slip faults (1)
- Strukturgeologie (1)
- Subduktion (1)
- Surface (1)
- Surface waves and free oscillations (1)
- TanDEM-X DEM (1)
- Tauern Window; (1)
- Taupo Rift (1)
- Temperature (1)
- Thick-skinned tectonics (1)
- Time series analysis (1)
- Time-series analysis (1)
- Torsion Experiments (1)
- Torsionsexperimente (1)
- Transfer function (1)
- Triassic rifting (1)
- Tropical lake (1)
- Trujillo Block (1)
- Ultra-low velocity zones (1)
- Uran (1)
- VERB (1)
- VLP (1)
- VT events and tremor (1)
- Varved sediments (1)
- Volcanic system (1)
- Walker circulation (1)
- Wasser-Gesteins-Wechselwirkungen (1)
- Water budget / balance (1)
- Waveform inversion (1)
- West Burma Terrane (1)
- Windböen (1)
- Winderosion (1)
- Wirtsgesteinsskala (1)
- Within-model uncertainty (1)
- XANES (1)
- XRD in the clay fraction (1)
- XRF analysis (1)
- Yangtze River (1)
- Yedoma (1)
- Zentral Asien (1)
- acoustic emissions (1)
- aegean (1)
- afterslip inversion (1)
- age-heterogeneity (1)
- agemodeling (1)
- air pollution (1)
- ambient noise (1)
- anaerobe Inkubationensexperimente (1)
- anaerobic incubation experiments (1)
- ancient DNA (1)
- andean geology (1)
- apatite geochemistry and U-Pb dating (1)
- aquatic carbon cycle (1)
- arctic (1)
- arktischer Nahküstenbereich (1)
- bacterial diversity (1)
- bacterial-community structure (1)
- barite (1)
- basement rock (1)
- basin modeling (1)
- biogeography (1)
- bioturbation (1)
- black carbon (1)
- body waves (1)
- bond strength (1)
- boreal (1)
- boreal forest (1)
- buildings (1)
- burial (1)
- carbon cycle (1)
- carbon fluxes (1)
- carbonate production (1)
- catchment (1)
- catchment nitrate export (1)
- catchment response (1)
- change (1)
- characteristics (1)
- charcoal (1)
- chemistry (1)
- chorus waves (1)
- city district (1)
- clay (1)
- cleaner energy transitions (1)
- climat change (1)
- climate adaptation (1)
- climate benefits (1)
- climate change adaptation (1)
- climate gradient (1)
- climate modeling (1)
- climate time series analysis (1)
- climate transition (1)
- clumped isotopes (1)
- code (1)
- compound-specific stable isotopes (1)
- computational ethnomusicology (1)
- computational geosciences (1)
- concentration (1)
- conflict (1)
- cosmic-rays (1)
- cosmogenic nuclides (1)
- covalency (1)
- creep and unmapped faults; (1)
- crustal structure (1)
- damage modelling (1)
- data-mining (1)
- deep biosphere (1)
- deep long-period earthquakes (1)
- deformation (1)
- degradation (1)
- density-driven flow (1)
- deposition (1)
- derived flood risk analysis (1)
- deterministic (1)
- detrital provenance (1)
- diamond anvil cell (1)
- dichtegetriebene Strömung (1)
- digital elevation models (1)
- digital twin (1)
- directivity analysis (1)
- disaster risk (1)
- discharge (1)
- discharge time series (1)
- disturbance (1)
- downscaling (1)
- drainage-divide migration (1)
- earth boundary layer (1)
- earth system sciences (1)
- earthquake damage (1)
- earthquake hydrology (1)
- earthquake physics (1)
- earthquake swarms (1)
- earthquakes (1)
- ecosystem service cascade (1)
- electrical conductivity (1)
- electrical resistivity (1)
- electrical resistivity tomography (1)
- electrochemistry (1)
- emergency management (1)
- empirical (1)
- enhanced geothermal system (1)
- enhanced geothermal systems (EGS) (1)
- environmental (1)
- environmentalism (1)
- equifinality (1)
- erosion (1)
- eruption (1)
- estimation (1)
- event characteristics (1)
- expedition (1)
- exposure (1)
- extensional tectonics (1)
- extreme seasons (1)
- fault network (1)
- fault reactivation (1)
- faults (1)
- fields (1)
- fire (1)
- flat-slab (1)
- flood frequency (1)
- flood modelling; (1)
- flood risk analysis (1)
- floodplain protection (1)
- floodplain wetlands (1)
- fluctuation (1)
- fluvial erosion (1)
- flux (1)
- forecasting (1)
- forecasting (1922, 4315, 7924, 7964) (1)
- forest (1)
- formation damage (1)
- forward stratigraphic modelling (1)
- fracture growth (1)
- fracture transmissivity (1)
- frequency-domain electromagnetics (1)
- ganga plains (1)
- gas flux (1)
- gas hydrate (1)
- gas hydrates (1)
- generative model (1)
- geochronology (1)
- geogenic degassing (1)
- geoinformatics (1)
- geomodeling (1)
- geomorphic connectivity (1)
- geostatistics (1)
- geothermal energy (1)
- geyser (1)
- global change (1)
- grain size (1)
- greenhouse gas (1)
- ground motion fields (1)
- ground motion modeling (1)
- groundwater (1)
- groundwater recharge (1)
- habitat (1)
- hazards (1)
- heat flow (1)
- heavy tail behavior (1)
- hellenic volcanic arc (1)
- hexadecane (1)
- high spatial resolution (1)
- high-pressure (1)
- historical geography (1)
- hominid (1)
- horizontaler Fluss (1)
- host rock scale (1)
- human evolution (1)
- hybrid (1)
- hydrate formation (1)
- hydrated silicate (1)
- hydraulische Risserzeugung (1)
- hydraulisches Aufbrechen (1)
- hydrodynamic interactions (1)
- hydrodynamic sorting (1)
- hydrogen bond (1)
- hydrological connectivity (1)
- hydrological modeling (1)
- hydrological uplift and subsidence (1)
- hydrothermal system; (1)
- ice complex (1)
- imaging (1)
- impact (1)
- incommensurate modulation (1)
- induced seismicity (1)
- injection (1)
- injection scheme (1)
- intercultural understanding (1)
- interdisciplinarity (1)
- interseismic strain rate (1)
- inverse analysis (1)
- inverse modeling (1)
- ionic liquids (1)
- iron (1)
- kinetic fractionation (1)
- knickpoints (1)
- lake system responses (1)
- larch (1)
- larch forest (1)
- laterally constrained inversion (1)
- lethal violence (1)
- level (1)
- lithosphere (1)
- low temperature thermochronology (1)
- low-frequency (1)
- machine learning (0555) (1)
- magma degassing (1)
- magma plumbing system (1)
- marine sediments (1)
- maschinelles Lernen (1)
- mathematical geology (1)
- melts (1)
- mesoscale heterogeneous catchment (1)
- metal-containing ionic liquids; (1)
- methane (1)
- methane hydrate (1)
- microbial community (1)
- microbial diversity (1)
- microbial mats (1)
- microplate (1)
- microstructural deformation mechanisms (1)
- minimum gradient support regularization (1)
- mining sciences (1)
- model (1)
- modeling; (1)
- modern pollen assemblages (1)
- molecular biomarkers (1)
- molekulare Biomarker (1)
- monsoon (1)
- morphometric indices (1)
- mountain growth (1)
- multiperspective reception of AvH (1)
- multisensor system (1)
- multivariate statistics (1)
- muons (1)
- near-surface geophysics (1)
- near-surface monitoring (1)
- neogene (1)
- neutrons (1)
- nitrogen (1)
- nitrogen legacies (1)
- normal faults (1)
- nuclear waste disposal (1)
- numerical simulation (1)
- numerical simulations (1)
- offene Daten (1)
- online (1)
- open data (1)
- organic carbon stabilization (1)
- organic matter (1)
- organisches Material (1)
- orographic rainfall (1)
- paleoceanography (1)
- paleoclimate (1)
- paleoclimatology (1)
- paleoseismology (1)
- parameter (1)
- peat characterization (1)
- pedogenic carbonate (1)
- pegmatite (1)
- periglacial process (1)
- permafost (1)
- permafrost sediments (1)
- permutation entropy (1)
- petrothermales System (EGS) (1)
- phase transition (1)
- physics based model (1)
- phytoplankton (1)
- planktonic foraminifera (1)
- planning indicators (1)
- plasma density (1)
- plastic degradation (1)
- plastisphere (1)
- pollen-vegetation-climate relationships (1)
- population pressure (1)
- poroelasticity (1)
- power-law rheology (1)
- precaution (1)
- precipitation (1)
- propagating uplift (1)
- provenance (1)
- quantitative vegetation reconstruction (1)
- quartäre Geochronologie (1)
- radial flow (1)
- radiale Strömung (1)
- radiocarbon dating (1)
- reactive transport simulation (1)
- reaktive Transportsimulation (1)
- reconstruction (1)
- redox processes (1)
- reduction (1)
- regional flood frequency analysis (1)
- relative pollen productivity (1)
- relaxation (1)
- remote sensing (1)
- renya Rift (1)
- reservoirs (1)
- rheology (1)
- rift (1)
- rift transfer zone (1)
- rifts (1)
- risk (1)
- risk management (1)
- river dynamics (1)
- river incision (1)
- rivers (1)
- rotational sensor (1)
- russische Arktis (1)
- salt rock (1)
- santorini (1)
- sediment (1)
- sediment dynamics (1)
- sediment routing system (1)
- sediment transport (1)
- sedimentary aquifer (1)
- seismic monitoring (1)
- seismicity model (1)
- sensitivity analysis (1)
- sequence stratigraphy (1)
- slope aspect (1)
- software (1)
- soil formation (1)
- soil moisture at field scale (1)
- soil-moisture (1)
- solid earth (1)
- sorption (1)
- source rock evaluation (1)
- spin (1)
- stabile Isotope (1)
- stable carbon isotopes (1)
- statistics (1)
- steric factors (1)
- stress measurement (1)
- strike-slip (1)
- sub-caldera structure (1)
- subcatchment response (1)
- subduction zone (1)
- submarine gas vents (1)
- submarine volcanism (1)
- subsurface life (1)
- sulfate reduction (1)
- surface type-function-concept (1)
- surface velocity (1)
- surface water (1)
- surface wave (1)
- surface wave, inversion, near surface (1)
- taiga (1)
- tectonic geodesy (1)
- temperature sensor (1)
- tensor inversion (1)
- terrestrial (1)
- tetrahalidometallates (1)
- thaw (1)
- thermochronological modelling (AFT, AHe and ZHe) (1)
- thermochronology (1)
- thermodynamic and kinetic properties (1)
- thermodynamische und kinetische Eigenschaften (1)
- thermokarst (1)
- thermokarst lakes (1)
- thermophiles; (1)
- time series analysis (1)
- tourmaline (1)
- traditional Georgian music (1)
- transition (1)
- travel time distribution (1)
- triaxial deformation experiments (1)
- triaxiale Deformationsexperimente (1)
- tropical climate (1)
- tundra (1)
- tuning (1)
- turbidity modelling (1)
- twin domains (1)
- ultra-relativistic electrons (1)
- upper tail (1)
- uranium (1)
- urban green (1)
- urban planning practice (1)
- variability (1)
- varved lake sediments (1)
- verbesserte geothermische Systeme (1)
- vertikaler Fluss (1)
- volcano-seismology (1)
- volcanoseismology (1)
- vulnerability (1)
- warfare (1)
- warvierte Seesedimente (1)
- water balance (1)
- water quality (1)
- water quality modeling (1)
- water rock interactions (1)
- water table (1)
- wetland (1)
- wetland health (1)
- wetland hydrology (1)
- wetland management (1)
- wind energy-biodiversity (1)
- wind energy-biodiversity conflict (1)
- wind gusts (1)
- winderosion (1)
- yedoma (1)
- yedoma ice complex (1)
Institute
- Institut für Geowissenschaften (201) (remove)
Marine sedimentary archives are routinely used to reconstruct past environmental changes. In many cases, bioturbation and sedimentary mixing affect the proxy time-series and the age-depth relationship. While idealized models of bioturbation exist, they usually assume homogeneous mixing, thus that a single sample is representative for the sediment layer it is sampled from.
However, it is largely unknown to which extent this assumption holds for sediments used for paleoclimate reconstructions.
To shed light on
1) the age-depth relationship and its full uncertainty,
2) the magnitude of mixing processes affecting the downcore proxy variations, and
3) the representativity of the discrete sample for the sediment layer, we designed and performed a case study on South China Sea sediment material which was collected using a box corer and which covers the last glacial cycle.
Using the radiocarbon content of foraminiferal tests as a tracer of time, we characterize the spatial age-heterogeneity of sediments in a three-dimensional setup. In total, 118 radiocarbon measurements were performed on defined small- and large-volume bulk samples ( similar to 200 specimens each) to investigate the horizontal heterogeneity of the sediment. Additionally, replicated measurements on small numbers of specimens (10 x 5 specimens) were performed to assess the heterogeneity within a sample volume. Visual assessment of X-ray images and a quantitative assessment of the mixing strength show typical mixing from bioturbation corresponding to around 10 cm mixing depth.
Notably, our 3D radiocarbon distribution reveals that the horizontal heterogeneity (up to 1,250 years), contributing to the age uncertainty, is several times larger than the typically assumed radiocarbon based age-model error (single errors up to 250 years). Furthermore, the assumption of a perfectly bioturbated layer with no mixing underneath is not met.
Our analysis further demonstrates that the age-heterogeneity might be a function of sample size; smaller samples might contain single features from the incomplete mixing and are thus less representative than larger samples.
We provide suggestions for future studies, optimal sampling strategies for quantitative paleoclimate reconstructions and realistic uncertainty in age models, as well as discuss possible implications for the interpretation of paleoclimate records.
The origin of the First Bend of the Yangtze River is key to understanding the birth of the modern Yangtze River. Despite considerable efforts, the timing and mechanism of formation of the First Bend remain highly debated. Inverse river-profile modeling of three tributaries (Chongjiang, Lima, and Gudu) of the Jinsha River, integrated with regional tectonic and geomorphic interpretations, allows the onset of incision at the First Bend to be constrained to 28-20 Ma. The spatio-temporal coincidence of initial river incision and activity of Yulong Thrust Belt in southeastern Tibet highlights thrusting to be fundamental in reshaping the pre-existing stream network at the First Bend. These results enable us to reinterpret a change in sedimentary environment from a braided river to a swamp-like lake in the Jianchuan Basin south of the First Bend, recording the destruction of the hypothesized southwards-flowing paleo-Jinsha and Shuiluo Rivers at ~36-35 Ma by magmatism. During the late Oligoceneearly Miocene, the paleo-Shuiluo River was diverted to the north by focused rock uplift due to thrusting along the Yulong Thrust Belt, which also led to exhumation of the Jianchuan Basin. Diversion of the paleo-Shuiluo River can be explained by capture from a downstream river in the footwall of the Yulong Thrust Belt. Subsequent rapid headward erosion, that was caused by thrusting-induced drop of local base level, is recorded by upstream younging ages for the onset of incision and led to the formation of the First Bend. The combination of new ages for the onset of incision at 28-20 Ma at the First Bend and younger ages upstream indicates northwards expansion of the Jinsha River at a rate of 62 +/- 18 mm/yr. Our results suggest that the origin of the First Bend was likely triggered by thrusting at 28-20 Ma, after which the Yangtze River formed.
Southeastern Tibetan Plateau growth revealed by inverse analysis of landscape evolution model
(2022)
The Cenozoic history of the Tibetan Plateau topography is critical for understanding the evolution of the Indian-Eurasian collision, climate, and biodiversity. However, the long-term growth and landscape evolution of the Tibetan Plateau remain ambiguous, it remains unclear if plateau uplift occurred soon after the India-Asia collision in the Paleogene (similar to 50-25 Ma) or later in the Neogene (similar to 20-5 Ma). Here, we reproduce the uplift history of the southeastern Tibetan Plateau using a 2D landscape evolution model, which simultaneously solves fluvial erosion and sediment transport processes in the drainage basins of the Three Rivers region (Yangtze, Mekong, and Salween Rivers). Our model was optimized through a formal inverse analysis with 20,000 forward simulations, which aims to reconcile the transient states of the present-day river profiles. The results, compared to existing paleoelevation and thermochronologic data, suggest initially low elevations (similar to 300-500 m) during the Paleogene, followed by a gradual southeastward propagation of topographic uplift of the plateau margin.
Ground motion with strong-velocity pulses can cause significant damage to buildings and structures at certain periods; hence, knowing the period and velocity amplitude of such pulses is critical for earthquake structural engineering.
However, the physical factors relating the scaling of pulse periods with magnitude are poorly understood.
In this study, we investigate moderate but damaging earthquakes (M-w 6-7) and characterize ground- motion pulses using the method of Shahi and Baker (2014) while considering the potential static-offset effects.
We confirm that the within-event variability of the pulses is large. The identified pulses in this study are mostly from strike-slip-like earthquakes. We further perform simulations using the freq uency-wavenumber algorithm to investigate the causes of the variability of the pulse periods within and between events for moderate strike-slip earthquakes.
We test the effect of fault dips, and the impact of the asperity locations and sizes. The simulations reveal that the asperity properties have a high impact on the pulse periods and amplitudes at nearby stations.
Our results emphasize the importance of asperity characteristics, in addition to earthquake magnitudes for the occurrence and properties of pulses produced by the forward directivity effect.
We finally quantify and discuss within- and between-event variabilities of pulse properties at short distances.
Flood risk management in Germany follows an integrative approach in which both private households and businesses can make an important contribution to reducing flood damage by implementing property-level adaptation measures. While the flood adaptation behavior of private households has already been widely researched, comparatively less attention has been paid to the adaptation strategies of businesses. However, their ability to cope with flood risk plays an important role in the social and economic development of a flood-prone region. Therefore, using quantitative survey data, this study aims to identify different strategies and adaptation drivers of 557 businesses damaged by a riverine flood in 2013 and 104 businesses damaged by pluvial or flash floods between 2014 and 2017. Our results indicate that a low perceived self-efficacy may be an important factor that can reduce the motivation of businesses to adapt to flood risk. Furthermore, property-owners tended to act more proactively than tenants. In addition, high experience with previous flood events and low perceived response costs could strengthen proactive adaptation behavior. These findings should be considered in business-tailored risk communication.
It is widely recognized that collisional mountain belt topography is generated by crustal thickening and lowered by river bedrock erosion, linking climate and tectonics(1-4). However, whether surface processes or lithospheric strength control mountain belt height, shape and longevity remains uncertain. Additionally, how to reconcile high erosion rates in some active orogens with long-term survival of mountain belts for hundreds of millions of years remains enigmatic. Here we investigate mountain belt growth and decay using a new coupled surface process(5,6) and mantle-scale tectonic model(7). End-member models and the new non-dimensional Beaumont number, Bm, quantify how surface processes and tectonics control the topographic evolution of mountain belts, and enable the definition of three end-member types of growing orogens: type 1, non-steady state, strength controlled (Bm > 0.5); type 2, flux steady state(8), strength controlled (Bm approximate to 0.4-0.5); and type 3, flux steady state, erosion controlled (Bm < 0.4). Our results indicate that tectonics dominate in Himalaya-Tibet and the Central Andes (both type 1), efficient surface processes balance high convergence rates in Taiwan (probably type 2) and surface processes dominate in the Southern Alps of New Zealand (type 3). Orogenic decay is determined by erosional efficiency and can be subdivided into two phases with variable isostatic rebound characteristics and associated timescales. The results presented here provide a unified framework explaining how surface processes and lithospheric strength control the height, shape, and longevity of mountain belts.
Understanding the key factors influencing the water quality of large river systems forms an important basis for the assessment and protection of cross-regional ecosystems and the implementation of adapted water management concepts. However, identifying these factors requires in-depth comprehension of the unique environmental systems, which can only be achieved by detailed water quality monitoring.
Within the scope of the joint science and sports event "Elbschwimmstaffel" (swimming relay on the river Elbe) in June/July 2017 organized by the German Ministry of Education and Research, water quality data were acquired along a 550 km long stretch of the Elbe River in Germany. During the survey, eight physiochemical water quality parameters were recorded in high spatial and temporal resolution with the BIOFISH multisensor system. Multivariate statistical methods were applied to identify and delineate processes influencing the water quality.
The BIOFISH dataset revealed that phytoplankton activity has a major impact on the water quality of the Elbe River in the summer months. The results suggest that phytoplankton biomass constitutes a substantial proportion of the suspended particles and that photosynthetic activity of phytoplankton is closely related to significant temporal changes in pH and oxygen saturation.
An evaluation of the BIOFISH data based on the combination of statistical analysis with weather and discharge data shows that the hydrological and meteorological history of the sampled water body was the main driver of phytoplankton dynamics. This study demonstrates the capacity of longitudinal river surveys with the BIOFISH or similar systems for water quality assessment, the identification of pollution sources and their utilization for online in situ monitoring of rivers.
Groundwater is critical in supporting current and future reliable water supply throughout Africa. Although continental maps of groundwater storage and recharge have been developed, we currently lack a clear understanding on how the controls on groundwater recharge vary across the entire continent. Reviewing the existing literature, we synthesize information on reported groundwater recharge controls in Africa. We find that 15 out of 22 of these controls can be characterised using global datasets. We develop 11 descriptors of climatic, topographic, vegetation, soil and geologic properties using global datasets, to characterise groundwater recharge controls in Africa. These descriptors cluster Africa into 15 Recharge Landscape Units for which we expect recharge controls to be similar. Over 80% of the continents land area is organized by just nine of these units. We also find that aggregating the Units by similarity into four broader Recharge Landscapes (Desert, Dryland, Wet tropical and Wet tropical forest) provides a suitable level of landscape organisation to explain differences in ground-based long-term mean annual recharge and recharge ratio (annual recharge / annual precipitation) estimates. Furthermore, wetter Recharge Landscapes are more efficient in converting rainfall to recharge than drier Recharge Landscapes as well as having higher annual recharge rates. In Dryland Recharge Landscapes, we found that annual recharge rates largely varied according to mean annual precipitation, whereas recharge ratio estimates increase with increasing monthly variability in P-PET. However, we were unable to explain why ground based estimates of recharge signatures vary across other Recharge Landscapes, in which there are fewer ground based recharge estimates, using global datasets alone. Even in dryland regions, there is still considerable unexplained variability in the estimates of annual recharge and recharge ratio, stressing the limitations of global datasets for investigating ground-based information.
A 3-D crustal shear wave velocity model and Moho map below the Semail Ophiolite, eastern Arabia
(2022)
The Semail Ophiolite in eastern Arabia is the largest and best-exposed slice of oceanic lithosphere on land. Detailed knowledge of the tectonic evolution of the shallow crust, in particular during and after ophiolite obduction in Late Cretaceous times is contrasted by few constraints on physical and compositional properties of the middle and lower continental crust below the obducted units. The role of inherited, pre-obduction crustal architecture remains therefore unaccounted for in our understanding of crustal evolution and the present-day geology. Based on seismological data acquired during a 27-month campaign in northern Oman, Ambient Seismic Noise Tomography and Receiver Function analysis provide for the first time a 3-D radially anisotropic shear wave velocity (V-S) model and a consistent Moho map below the iconic Semail Ophiolite. The model highlights deep crustal boundaries that segment the eastern Arabian basement in two distinct units. The previously undescribed Western Jabal Akhdar Zone separates Arabian crust with typical continental properties and a thickness of similar to 40-45 km in the northwest from a compositionally different terrane in the southeast that is interpreted as a terrane accreted during the Pan-African orogeny in Neoproterozoic times. East of the Ibra Zone, another deep crustal boundary, crustal thickness decreases to 30-35 km and very high lower crustal V-S suggest large-scale mafic intrusions into, and possible underplating of the Arabian continental crust that occurred most likely during Permian breakup of Pangea. Mafic reworking is sharply bounded by the (upper crustal) Semail Gap Fault Zone, northwest of which no such high velocities are found in the crust. Topography of the Oman Mountains is supported by a mild crustal root and Moho depth below the highest topography, the Jabal Akhdar Dome, is similar to 42 km. Radial anisotropy is robustly resolved in the upper crust and aids in discriminating dipping allochthonous units from autochthonous sedimentary rocks that are indistinguishable by isotropic V-S alone. Lateral thickness variations of the ophiolite highlight the Haylayn Ophiolite Massif on the northern flank of Jabal Akhdar Dome and the Hawasina Window as the deepest reaching unit. Ophiolite thickness is similar to 10 km in the southern and northern massifs, and <= 5 km elsewhere.