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Well-constrained fault slip rates are important for understanding strain partitioning within a fault system and the associated seismic hazard. The Haiyuan fault is a significant active strike-slip fault in the northeast margin of the Tibetan Plateau with ongoing controversy over its late Pleistocene slip rate. Previous work by Lasserre et al. (1999) suggested a slip rate of 12 ± 4 mm/year, which is higher than recent geodetically determined rates on adjacent fault sections. We reanalyze and reevaluate the slip rates benefiting from new high-resolution airborne Light Detection and Ranging data at their two sites, located north of the Songshan village. Based on this data, we revise field-mapped offset constraints. At the Majia Wan site, we document a sinistral displacement of 130 ± 10 m of the crest and 93 ± 15 m of the base of T1/T2 terrace riser, respectively. At the Xuanma Wan site, the offset of T4/T1′ terrace riser is updated to be 68 +3 / −10 m. Combining new geochronology dates, we assess the abandonment age of T2 as 26.0 ± 4.5 ka and T1 as 9,445 ± 30 year. These data suggest a slip rate between 5.0 +1.5 / −1.1 and 8.9 +0.5 / −1.3 mm/year since~26 ka, based on the upper terrace and lower terrace reconstruction, respectively. Our reevaluation supports that apparent slip rate discrepancies in northern Tibet possibly share a systematic bias due to the use of lower-terrace reconstruction to interpret the age of offset. Key Points:• Slip rate of the Haiyuan fault near longitude 37°is determined to be between 5.0 and 8.9 mm/year over the last~26 ka • Lower bound in geologic slip rate is similar to geodetic strain rate Supporting Information:• Supporting Information S1• Data Set S1

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High-resolution topographic or imagery data effectively reveal geomorphic offsets along faults that can be used to deduce slipper event of recurrent rupture events. Documentation of patterns of geomorphic offsets is scarce on faults that undergo both creep and coseismic rupture. In this paper, we used newly acquired high-resolution light detection and ranging (LiDAR) data to compile geomorphic offsets along the Laohu Shan section of the Haiyuan fault, in the northern Tibetan Plateau, where interferometric synthetic aperture radar (InSAR) data suggest creep presently occurs over a 35-km-long stretch at a rate comparable to the long-term geological slip rate, despite evidence for past coseismic fault rupture. Numerous offset gullies identified using the LiDAR data yield a range of offsets from less than 2 m up to 50 m. These offsets have well-separated probability density peaks at 2-3 m, ~7 m, and ~14 m, with increments of 2-3 m, 4-6 m, and 5-7 m. The sequence of paleoseismic events along the Laohu Shan section indicates that the gullies with offsets of 2-3 m are likely related to surface rupture of the historical 1888 Jingtai earthquake, plus subsequent creep. Offset increments of 4-6 m and 5-7 m may represent coseismic slip in past paleoseismic events plus creep during the interseismic period. The creeping Laohu Shan section preserves numerous discrete cumulative offsets, with an offset clustering pattern indistinguishable from that on a locked fault with recurrent earthquake ruptures. Association of offset increments with known paleoseismic events yields a slip rate of 3-5 mm/yr during the past 200 years, roughly similar to the ~5 mm/yr creep rate. If the ratio of surface creep rate to the total fault slip rate has been continuous, then seismic moment release by brittle ruptures, and thus seismic hazard, would be much reduced on the Laohu Shan section of the Haiyuan fault. Alternatively, the current high creep rate may be a transient phenomenon, perhaps after slip following the 2000 Jingtai Mw 5.6 earthquake or in response to the adjacent 1920 M ~8 Haiyuan earthquake rupture that terminated immediately to the east.

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Background: A novel coronavirus pneumonia outbreak began in Wuhan, Hubei Province, in December 2019; the outbreak was caused by a novel coronavirus previously never observed in humans. China has imposed the strictest quarantine and closed management measures in history to control the spread of the disease. However, a high level of evidence to support the surgical management of potential trauma patients during the novel coronavirus outbreak is still lacking. To regulate the emergency treatment of trauma patients during the outbreak, we drafted this paper from a trauma surgeon perspective according to practical experience in Wuhan. Main body:The article illustrates the general principles for the triage and evaluation of trauma patients during the outbreak of COVID-19, indications for emergency surgery, and infection prevention and control for medical personnel, providing a practical algorithm for trauma care providers during the outbreak period. Conclusions:The measures of emergency trauma care that we have provided can protect the medical personnel involved in emergency care and ensure the timeliness of effective interventions during the outbreak of COVID-19.