Preprints
Search for earthquake (526 results)
The impact of earthquake cycle variability on neotectonic and paleoseismic slip rate estimates
Published: 2018-05-28
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Because of the natural variability (aleatoric uncertainty) in earthquake recurrence intervals and coseismic displacements on a fault, cumulative slip on a fault does not increase linearly or perfectly step-wise with time; instead, some amount of variability in shorter-term slip rates results. Though this variability could greatly affect the accuracy of neotectonic (i.e., late Quaternary) and [...]
Crack models of repeating earthquakes predict observed moment-recurrence scaling
Published: 2018-05-24
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Small repeating earthquakes are thought to represent rupture of isolated asperities loaded by surrounding creep. The observed scaling between recurrence interval and seismic moment, Tr ~ M^(1/6), contrasts with expectation assuming constant stress drop and no aseismic slip (Tr ~ M^(1/3)). Here we demonstrate that simple crack models of velocity-weakening asperities embedded in a [...]
Measuring Higher-Mode SurfaceWave Dispersion Using a Transdismensional Bayesian Approach
Published: 2018-05-21
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We present a method for measuring the dispersion of higher mode surface wave phase velocities from a single seismogram using a hierarchical transdimensional Bayesian approach. The 1-D shear velocity profiles down to 800km depth between sources and seismic stations are regarded as the controlling parameters to tune the phase velocities of fundamental and higher modes. The misfits between [...]
Strain budget of the Ecuador-Colombia subduction zone: a stochastic view
Published: 2018-04-24
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The 2016 Pedernales earthquake (Mw=7.8) ruptured a portion of the Colombia-Ecuador subduction interface where several large historical earthquakes have been documented since the great 1906 earthquake (M=8.6). Considering all significant ruptures that occurred in the region, it has been suggested that the cumulative moment generated co-seismically along this part of the subduction over the last [...]
Controls on early‐rift geometry: new perspectives from the Bilila‐Mtakataka fault, Malawi
Published: 2018-04-23
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
This study investigates the controls to fault and rift geometry for a young rift system. Our case study is a large fault in southern Malawi. The geometry of the fault at the surface, the scarp, and structures within the rocks the fault cuts through, are measured. We also calculate the scarp height. The orientation and height of the fault scarp implies that local stresses influence its geometry, [...]
Bimodal or quadrimodal? Statistical tests for the shape of fault patterns
Published: 2018-04-23
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Natural fault patterns, formed in response to a single tectonic event, often display significant variation in their orientation distribution. The cause of this variation is the subject of some debate: it could be ‘noise’ on underlying conjugate (or bimodal) fault patterns or it could be intrinsic ‘signal’ from an underlying polymodal (e.g. quadrimodal) pattern. In this contribution, we present [...]
Present-day stress orientations in the Great Sumatran Fault in North Sumatra
Published: 2018-04-20
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Trench-parallel strike slip faults develop at lithospheric scale during oblique high-angle subduction. A “sliver” plate forms due to slip partitioning between the subduction plane (margin-normal slip) and the strike slip fault (margin-parallel slip). This process ultimately controls the location of volcanoes and earthquakes. The Great Sumatran Fault (GSF) is a showcase of this tectonic [...]
The relationships between regional Quaternary uplift, deformation across active normal faults and historical seismicity in the upper plate of subduction zones: The Capo D’Orlando Fault, NE Sicily.
Published: 2018-04-20
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics
In order to investigate deformation within the upper plate of the Calabrian subduction zone we have mapped and modelled a sequence of Late Quaternary palaeoshorelines tectonically‐deformed by the Capo D’Orlando normal fault, NE Sicily, which forms part of the actively deforming Calabrian Arc. In addition to the 1908 Messina Strait earthquake (Mw 7.1), this region has experienced damaging [...]
The seismic history of the Pisia fault (eastern Corinth rift, Greece) from fault plane weathering features and cosmogenic 36Cl dating
Published: 2018-04-14
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
The deformation of the eastern Corinth rift (Greece) is distributed along several E-W trending active normal faults. Here, the 25-km-long Pisia fault experienced up to 150 cm of coseismic displacement during the 1981 Alkyonides earthquake sequence (M = 6.7, 6.4, 6.3). Using terrestrial laser scanning, coupled with analyses of color changes, lichen colonization and karstic features, we identify [...]
Topography and the shallow slip deficit inference
Published: 2018-04-13
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Images of earthquake slip serve as the foundation for understanding the distribution of coseismic energy release, theories about rupture propagation, and fault mechanics. Geodetic slip images are inferred using elastic models that link surface observations to fault activity at depth. To date, almost all elastic models used for these common calculations [10, 14, 19, 23] include the assumption that [...]
Rapid mantle flow with power-law creep explains deformation after the 2011 Tohoku mega-quake
Published: 2018-04-11
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The deformation transient that follows large subduction zone earthquakes is thought to originate from the interaction of viscoelastic flow in the asthenospheric mantle and slip on the megathrust that are both accelerated by the sudden coseismic stress change. The surface deformation following the 2011 Mw 9.0 Tohoku earthquake provides some of the most comprehensive constraints on surface [...]
Asthenosphere flow modulated by megathrust earthquake cycles
Published: 2018-04-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Subduction megathrusts develop the largest earthquakes, often close to large population centers. Understanding the dynamics of deformation at subduction zones is therefore important to better assess seismic hazards. Here, I develop consistent earthquake cycle simulations that incorporate localized and distributed deformation based on laboratory-derived constitutive laws by combining boundary and [...]
Coulomb stress transfer and fault interaction over millennia on non-planar active normal faults: the Mw 6.5-5.0 seismic sequence of 2016-2017, central Italy.
Published: 2018-03-27
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
In order to investigate the importance of including strike-variable geometry and the knowledge of historical and palaeoseismic earthquakes when modelling static Coulomb stress transfer and rupture propagation, we have examined the August–October 2016 A.D. and January 2017 A.D. central Apennines seismic sequence (Mw 6.0, 5.9, 6.5 in 2016 A.D. (INGV) and Mw 5.1, 5.5, 5.4, 5.0 in 2017 A.D. [...]
Time-dependent compaction as a mechanism for regular stick-slips
Published: 2018-03-27
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Owing to their destructive potential, earthquakes receive considerable attention from laboratory studies. In friction experiments, stick-slips are studied as the laboratory equivalent of natural earthquakes, and numerous attempts have been made to simulate stick-slips numerically using the Discrete Element Method (DEM). However, while laboratory stick-slips commonly exhibit regular stress drops [...]
Rheological transitions facilitate fault-spanning ruptures on seismically active and creeping faults
Published: 2018-03-27
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
The apparent stochastic nature of earthquakes poses major challenges for earthquake forecasting attempts. Physical constraints on the seismogenic potential of major fault zones may aid in improving seismic hazard assessments, but the mechanics of earthquake nucleation and rupture are obscured by the complexity that faults display. In this work, we investigate the mechanisms behind giant [...]