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The distribution and magnitude of forces driving lithospheric deformation in the India‐Eurasia collision zone have been debated over many decades. Here we test a two‐dimensional (2‐D) Thin Viscous Shell approach that has been adapted to explicitly account for displacement on major faults and investigate the impact of lateral variations in depth‐averaged lithospheric strength. We present a suite of dynamic models to explain the key features from new high‐resolution Sentinel‐1 Interferometric Synthetic Aperture Radar as well as Global Navigation Satellite System velocities. Comparisons between calculated and geodetically observed velocity and strain rate fields indicate: (a) internal buoyancy forces from Gravitational Potential Energy acting on a relatively weak region of highest topography (>2,000 m) contribute to dilatation of the high plateau and contraction on the margins; (b) a weak central Tibetan Plateau (∼1021 Pa s compared to far‐field depth‐averaged effective viscosity of at least 1022–1023 Pa s) is required to explain the observed long‐wavelength eastward velocity variation; (c) localized displacement on fault systems enables strain concentration and clockwise rotation around the Eastern Himalayan Syntaxis. We discuss the tectonic implications for rheology of the lithosphere, distribution of geodetic strain, and partitioning of active faulting and seismicity. Plain Language Summary: The collision of the Indian Plate with Eurasia has created the Tibetan Plateau, one of the largest deforming regions in the continents. The mode of deformation has been a focus for heated debate and has inspired two contrasting tectonic models: (a) The deformation is localized on major faults separating "blocks" or (b) the strain is distributed throughout a "continuum." We approximate the India‐Eurasia collision by treating the continent as a thin viscous shell with regional variations in strength, explicitly accounting for displacements on selected major faults. We present a suite of models to explain the key features of new geodetic measurements from satellites. The best‐fit model involves a weak Tibetan Plateau, a particularly weaker central plateau, and four strong regions outside the plateau, and allows displacements on major faults. This represents the deformation field of the India‐Eurasia collision zone as a combination of continuous distributed deformation and focused strain on major faults. Key Points: A suite of faulted viscous shell models testing key parameters explain new observations from geodesy for the India‐Asia collisionThe India‐Asia collision is explained by the balance between buoyancy and boundary forces, slip on faults, and internal strength variationsCentral Tibetan Plateau has a vertically‐averaged effective viscosity of ∼1021 Pa s, 1–2 orders lower than the surrounding area [ABSTRACT FROM AUTHOR]

Following earthquakes, faults are often observed to continue slipping aseismically. It has been proposed that this afterslip occurs on parts of the fault with rate-strengthening friction that are stressed by the main shock, but our understanding has been limited by a lack of immediate, high-resolution observations. Here we show that the behavior of afterslip following the 2014 South Napa earthquake in California varied over distances of only a few kilometers. This variability cannot be explained by coseismic stress changes alone. We present daily positions from continuous and survey GPS sites that we remeasured within 12 h of the main shock and surface displacements from the new Sentinel-1 radar mission. This unique geodetic data set constrains the distribution and evolution of coseismic and postseismic fault slip with exceptional resolution in space and time. We suggest that the observed heterogeneity in behavior is caused by lithological controls on the frictional properties of the fault plane.

Satellite-based earth observation sensors are increasingly able to monitor geophysical signals related to natural hazards, and many groups are working on rapid data acquisition, processing, and dissemination to data users with a wide range of expertise and goals. A particular challenge in the meaningful dissemination of Interferometric Synthetic Aperture Radar (InSAR) data to non-expert users is its unique differential data structure and sometimes low signal to noise ratio. In this study, we evaluate the online dissemination of ground deformation measurements from InSAR through Twitter, alongside the provision of open access InSAR data from the Centre for Observation and Modelling of Earthquakes, Volcanoes and Tectonics (COMET) Looking Into Continents from Space with Synthetic Aperture Radar (LiCSAR) processing system. Our aim is to evaluate (1) who interacts with disseminated InSAR data, (2) how the data are used and (3) to discuss strategies for meaningful communication and dissemination of open InSAR data. We found that InSAR Twitter activity was primarily associated with natural hazard response, specifically following earthquakes and volcanic activity, where InSAR measurements of ground deformation were disseminated, often using wrapped and unwrapped interferograms. For earthquake events, Sentinel-1 data were acquired, processed, and tweeted within 4.7±2.8 days (shortest was one day). Open access Sentinel-1 data dominated the InSAR tweets and were applied to volcanic and earthquake events in the most engaged with (retweeted) content. Open access InSAR data provided by LiCSAR was widely accessed, including automatically processed and tweeted interferograms and interactive event pages revealing ground deformation following earthquake events. The further work required to integrate dissemination of InSAR data into longer-term disaster risk reduction strategies is highly specific, both to hazard-type, international community of practice, and local political setting and civil protection mandates. Notably, communication of uncertainties and processing methodologies are still lacking. We conclude by outlining the future direction of COMET LiCSAR products to maximise their useability. [ABSTRACT FROM AUTHOR]

In the continents, the importance of earthquakes that occur away from major block‐bounding faults is still debated. The 21 May 2021 MW ∼ 7.4 Maduo earthquake occurred on a secondary fault away from previously‐identified major block boundaries. Here we use 7 years of Sentinel‐1 Interferometric Synthetic Aperture Radar (InSAR) time series (between October 2014 and November 2021) to determine the distribution of coseismic slip and early postseismic afterslip following the Maduo earthquake, and the preceding interseismic strain accumulation. We devised a 13‐segment 3‐D fault geometry constrained by the SAR range offsets and the distribution of relocated aftershocks and used a Bayesian method incorporating von Karman regularization to solve for coseismic slip and afterslip models. We also used teleseismic waveforms as a standalone inversion to show the rupture evolution in space and time during the earthquake, finding that it propagates bilaterally with three notable rupture episodes. Our preferred coseismic self‐similar slip model shows a moderate shallow slip deficit, with the majority of moment release occurring in the depth interval of 1–10 km. The coseismic slip deficit is taken up in part by afterslip at shallow (<4 km) depths that grows linearly with time during the first ∼6 months, and at >10 km depths where afterslip grows logarithmically with time. We suggest that this heterogeneity is likely controlled by spatial variations in fault friction related to lithology. We discuss the implications for seismic hazard away from major tectonic block boundaries in light of our observations of the earthquake cycle on this intrablock fault. Plain Language Summary: Collision between the Indian and Eurasian plates has created the largest deforming region on the planet. Part of the resultant deformation is accommodated by movements on block‐bounding faults where major earthquakes usually occur. A large earthquake ruptured a slow‐moving fault away from the major pre‐identified block boundaries on 21 May 2021. We used 7 years of satellite radar images to measure the deformation that occurred before, during, and after the earthquake. We also used seismic observations to investigate the temporal evolution of the earthquake rupture. Our model agrees with the results from field mapping. Postseismic deformation at shallow and deep depths shows different temporally varying behavior, which is likely caused by the frictional properties of the fault associated with different physical characteristics of rocks. The causative fault was accumulating relatively subtle strain before the earthquake. We observed the strain being localized on one of the faults in the block interior, highlighting elevated earthquake potential in the future. Key Points: We present the earthquake cycle deformation for the 2021 Maduo earthquake from Sentinel‐1 Interferometric Synthetic Aperture Radar and teleseismic waveformsCoseismic slip deficit is taken up by shallow and deep afterslip with different temporal behavior; this may be controlled by lithologyInterseismic strain observed in the interior of a mapped tectonic block highlights importance of seismic hazard away from block boundaries [ABSTRACT FROM AUTHOR]

Active warning systems are traffic control devices consisting of variable signs or flashing beacons with conventional warning signs, which are activated by sensors detecting real-time roadway, environmental, and operational hazards. Currently most active warning systems detect and warn drivers of variable weather or pavement conditions, high-risk vehicle operating speeds, or the presence of intermittent hazards such as other vehicles, pedestrians, or wild animals. Within the Intelligent Transportation Systems framework, active warning systems applications detect these and other variable hazards and communicate these warnings directly to the vehicle or operator. Because most active warning systems are relatively recent, limited long-term system performance data are available. Testing and evaluation of active warning signs should continue to more firmly establish their benefits to highway safety and traffic operations. This paper provides an overview of available active warning systems and discusses their implementation requirements and potential benefits based on results and recommendations from evaluation studies. CE Database subject headings: Traffic safety; Traffic control devices; Traffic signs; Intelligent transportation systems.

As with people of the distant past, contemporary Americans inter funerary remains or 'grave goods' with their dead. The analysis of contemporary artifact interment in the United States is an initial focus of this study. Survey data gathered from 22 morticians in seven states have been used to explain modern funerary trends and motives of the bereaved. A second and more sensitive questionnaire was distributed by morticians to individuals who has placed artifacts in a relative's burial. Their responses give direct personal insights from which scholars may gain an understanding of the importance of grave goods to those who bury them with their dead.