Abstract. Accurate and rapid assessment of seismic intensity after a destructive earthquake is essential for efficient early emergency response. Here, we propose an improved method for assessing seismic intensity by analysing aftershock sequences that occur within 2 h of mainshock. The implementation and specific utilisation of the method were demonstrated using specific earthquake examples. Then, the conditions for the application of the method were summarised based on the results of 59 earthquake events that occurred globally during 2000–2022. Very early aftershocks could roughly characterise the basic features of the mainshock rupture. The curve fitted to the aftershock sequence using the robust locally weighted regression programme (Lowess) was very close to the surface rupture in the linear directional mean. The Lowess-fitted curve showed that the aftershocks distributed at some distance from the tips of the fault may have been generated at very early stages of the earthquake. The results of Lowess were closer to the fault rupture situation when Mw ≥7.0 and aftershock numbers were 40–100. Aftershock catalogues obtained by conventional means are steadily to assess the seismic intensities within 1.5 h. When the aftershock numbers were large enough, the intensity assessment time could be greatly reduced. The ground motion attenuation model provided best values at Mw ≥7.5. Our work exploits early accessible data more efficiently by extending the data sources for seismic intensity assessment and is a significant reference point for exploring the relationship between early aftershock events and faults planes.
In this paper, change of land cover and use type was first studied through interpretation of the two images (2007 and 2018), and then, dynamic evaluation of ecological service value in Southern Mountainous Areas of Jinan was made with evaluation system and equivalent factors built by Xie GD based on Costanza’s system. The results revealed that the area of bare land and grass land decreased by 4875.48 hm2 and 55141.56 hm2 respectively, on the contrary, cultivated land, forestland and building land has increased by 26915.671 hm2, 32261.31 hm2 and 1442.16 hm2 respectively. The ecological service value showed the increasing trend generally, among of which water conservation, air regulation, land protection, recreation have increased distinctly, which can be explained that the control develop strategies had taken action actively.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.