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Understanding rates and variability of Earth-surface processes is vital to assessing natural hazards, landscape response to climate change and addressing concerns related to food security and water supply. Surface processes affect the critical zone, where life interacts with the land surface, and are archived in sediment records. Luminescence dating provides an age estimate for sediment deposition and can provide dates to calculate rates and recurrence intervals of natural hazards and Earth-surface processes. This method has produced robust age estimates from a wide range of terrestrial, marine, tectonic, and archaeological settings. Importantly, luminescence dating covers an age range that spans the last several decades to the last several hundred thousand years, providing critical rates and dates for evaluating processes that are important to society.
Abstract. The database presented here contains radiogenic neodymium and strontium isotope ratios measured on both terrestrial and marine sediments. The main purpose of this dataset is to help assess sediment provenance and transport processes for various time intervals. This can be achieved by either mapping sediment isotopic signature and/or fingerprinting source areas using statistical tools. The database has been built by incorporating data from the literature and the SedDB database and harmonizing the metadata, especially units and geographical coordinates. The original data were processed in three steps. Firstly, specific attention has been devoted to providing geographical coordinates to each sample in order to be able to map the data. When available, the original geographical coordinates from the reference (generally DMS coordinates) were transferred into the decimal degrees system. When coordinates were not provided, an approximate location was derived from available information in the original publication. Secondly, all samples were assigned a set of standardized criteria that help split the dataset into specific categories. For instance, samples were distinguished according to their location (“Region”, “Sub-region” and “Location” that relate to locations at continental to city or river scale) or the sample type (terrestrial samples – “aerosols”, “soil sediments”, “river sediments”, “rocks” – or marine samples – “marine sediment” or “trap sample”). Finally, samples were distinguished according to their deposition age, which allowed us to compute average values for specific time intervals. Graphical examples illustrating the functionality of the database are presented and the validity of the process was tested by comparing the results with published data. The dataset will be updated bi-annually in order to add more data points to increase the sampling density or provide new types of samples (e.g. seawater signature) and/or integrate additional information regarding the samples. It is publicly available (under CC4.0-BY Licence) from the GFZ data management service at https://doi.org/10.5880/GFZ.4.3.2019.001.
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Earth surface processes, landforms and sediment deposits are intimately related - involving erosion of rocks, generation of sediment, and transport and deposition of sediment through various Earth surface environments. These processes, and the landforms and deposits that they generate, have a fundamental bearing on engineering, environmental and public safety issues; on recovery of economic resources; and on our understanding of Earth history. This textbook brings together the traditional disciplines of sedimentology and geomorphology to explain Earth surface processes, landforms and sediment deposits in a comprehensive and integrated way. It is the ideal resource for a two-semester course in sedimentology, stratigraphy, geomorphology, and Earth surface processes from the intermediate undergraduate to beginning graduate level. The book is also accompanied by a website hosting illustrations and material on field and laboratory methods for measuring, describing and analyzing Earth surface processes, landforms and sediments.
The Backrooms began as a single eerie image of empty yellow rooms, but internet users transformed it into a vast fictional world that feels disturbingly real。 Through videos, games, maps, survival guides and social media stories, audiences do more than watch the horror unfold。 They help build and explore it
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The V4 Superchargers will show up in the Tesla nav app and have NACS and CCS1 plugs
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A person’s sleeping brain may reveal warning signs of dementia long before memory problems begin。 Researchers used machine learning to analyze EEG recordings from about 7,000 adults and found that an older-than-expected “brain age” was tied to a sharply higher dementia risk。 Every additional 10 years of brain aging raised that risk by nearly 40%