Models Of Crustal Deformation Research Articles

Detectability analysis of interplate fault slips in the Nankai subduction thrust using seafloor observation instruments

To help the decision making regarding where to locate new observation instruments on the seafloor, we examined the detectability of interplate earthquakes and slow slips in the Nankai subduction thrust in Japan using seafloor observation instruments. Here, the detectability is defined as the smallest magnitude of the interplate fault slip detected by the assumed observation points based on crustal deformation simulation. In the detectability analyses, we considered the effect of sensor drifts that are particularly associated with seafloor observations. In addition, we introduced high-resolution three-dimensional (3D) finite element modeling of crustal deformation to consider the effect of the topography and 3D heterogeneous crustal structure around the Nankai Trough. The results of the detectability analyses show that introducing new seafloor stations for tilt observation in the Nankai region should increase the detectability of small- or medium-sized interplate earthquakes and slow slips significantly. Based on the obtained results, we also discuss the advantage of both the existing and the new observation instruments in detecting interplate fault slips.

A unified three-dimensional model of the lithospheric structure at the subduction corner in southeast Alaska: Summary results from STEEP

AbstractWe merge structural results from the ST. Elias Erosion/tectonics Project (STEEP), other studies, and seismicity data to build a comprehensive, three-dimensional model of the lithosphere of the subduction corner in southern Alaska. The model is defined by three surfaces: (1) a top of the subducting lithosphere surface, (2) Moho surfaces, and (3) a base of subducting lithosphere surface. We model the eastern edge of the subducting lithosphere using the southern tip of the Yakutat microplate as an anchor. Kinematic reconstructions using that anchor suggest the modern Fairweather fault is likely inherited from motion of the margin in the 6–10 Ma period. We constructed a 4D kinematic model of crustal deformation in the vicinity of Mount St. Elias. We call this model the middlebuster model because the geometry is similar to a two-sided plow with that name. The west side of the plow is the eastern limit of the Aleutian megathrust constructed from the union of constraints from STEEP seismic results and slip models of the 1979 St. Elias earthquake. The east side is inferred from geologic mapping and slip models of the 1899 Yakutat Bay earthquake sequence. The top of the plow is near the Seward Glacier, where previous studies showed near world-record exhumation rates. GPS velocity vectors show a large rotation across the syntaxis at Mount St. Elias. West of the syntaxis, faults inferred from inversion of the GPS data are above the megathrust inferred from seismic imaging. That and other evidence suggest the presence of a wedge of ductile crust that partially decouples the subducting mantle lithosphere from the upper crust in the area near the suture with the Yakutat microplate.

Crustal azimuthal anisotropy in the trans-North China orogen and adjacent regions from receiver functions

The North China Craton (NCC) is an important part of eastern China. Recent studies have shown that the eastern NCC (ENCC) has undergone significant lithospheric thinning and destruction since the late Mesozoic. Destruction of the cratonic lithosphere is necessarily accompanied by crustal deformation. Therefore, a detailed crustal deformation model can provide basic observational constraints for understanding the process and mechanisms of the destruction of the NCC. In this study, we estimated the crustal azimuthal anisotropy beneath 198 broadband stations in the NCC with a joint analysis of Ps waves converted at the Moho from radial and transverse receiver function data. We also performed a harmonic analysis to test the reliability of the measured anisotropy. We obtained robust crustal azimuthal anisotropy beneath 23 stations that are mostly located on the western margin of the Bohai Bay Basin, Yin-Yan orogenic belt, and Taihang Mountains, which reflects the crustal deformation characteristics in those regions. The crustal shear wave splitting time was found to range from 0.05 s to 0.68 s, with an average value of 0.23 s, which reveals a distinct crustal anisotropy in the Trans-North China Orogen (TNCO) and its adjacent areas. Our analysis of the results suggests that the strong NW-SE tectonic extension in the late Mesozoic and Cenozoic played an important role in crustal anisotropy in this region. In addition, the E-W trending crustal anisotropy on the margin of the Bohai Bay Basin indicates an effect of the ENE-WSW trending horizontal principal compressive stress. The crustal anisotropy in the Yin-Yan orogenic belt may be an imprint of the multiple-phase shortening of a dominant N-S direction from the early-to-middle Jurassic to the Early Cretaceous. Stations in the Taihang Mountains show large splitting times and well-aligned NW-SE fast directions that correlate with those measured from SKS splitting and that are possibly related to the lithospheric modification and magmatic underplating from the Late Mesozoic to Cenozoic in this area.

A Fault‐Based Model for Crustal Deformation in the Western United States Based on a Combined Inversion of GPS and Geologic Inputs

A Fault‐Based Model for Crustal Deformation in the Western United States Based on a Combined Inversion of GPS and Geologic Inputs

A continuum model of present-day crustal deformation in the Pamir-Tien Shan region constrained by GPS data

We present a new model of crustal deformation in the Pamir-Tien Shan region. There are two different ways of assessing the deformation: block and continuum modeling. In this study we adopt a continuum modeling approach, which is based on computation of the two-dimensional strain rate tensor field of the Earth’s crust. This approach allows independent computation of the deformation at any point of the computation grid by solving an over-constrained system of linear algebraic equations based on the linear term of the Taylor series expansion of the point velocity function about its radius-vector. We propose a detailed description of this method including a significance criterion introduced by the author for estimating the reliability of modeling results. We discuss the parameters of this deformation model for the Pamir-Tien Shan region, computed from the GPS velocity data measured at 506 sites of the Central Asian GPS network. The most distinctive features of the estimated strain field are N-S shortening of the largest basins in the Tien Shan and at the junction between the Pamir and Tien Shan, as well as the westward motion of the eastern and western boundaries of the Pamir relative to the Tarim plate and Tajik depression.

Subsurface fault geometries in Southern California illuminated through Full-3D Seismic Waveform Tomography (F3DT)

More precise spatial descriptions of fault systems play an essential role in tectonic interpretations, deformation modeling, and seismic hazard assessments. The recent developed full-3D waveform tomography techniques provide high-resolution images and are able to image the material property differences across faults to assist the understanding of fault systems. In the updated seismic velocity model for Southern California, CVM-S4.26, many velocity gradients show consistency with surface geology and major faults defined in the Community Fault Model (CFM) (Plesch et al. 2007), which was constructed by using various geological and geophysical observations. In addition to faults in CFM, CVM-S4.26 reveals a velocity reversal mainly beneath the San Gabriel Mountain and Western Mojave Desert regions, which is correlated with the detachment structure that has also been found in other independent studies. The high-resolution tomographic images of CVM-S4.26 could assist the understanding of fault systems in Southern California and therefore benefit the development of fault models as well as other applications, such as seismic hazard analysis, tectonic reconstructions, and crustal deformation modeling.

The Tethyan Himalayan detrital record shows that India–Asia terminal collision occurred by 54 Ma in the Western Himalaya

The Himalayan orogen is a type example of continent–continent collision. Knowledge of the timing of India–Asia collision is critical to the calculation of the amount of convergence that must have been accommodated and thus to models of crustal deformation. Sedimentary rocks on the Indian plate near the suture zone can be used to constrain the time of collision by determining first evidence of Asian-derived material deposited on the Indian plate. However, in the Himalaya, for this approach to be applied successfully, it is necessary to be able to distinguish between Asian detritus and detritus from oceanic island arcs that may have collided with India prior to India–Asia collision. Zircons from the Indian plate, Asian plate and Kohistan–Ladakh Island arc can be distinguished based on their U–Pb ages combined with Hf signatures. We undertook a provenance study of the youngest detrital sedimentary rocks of the Tethyan Himalaya of the Indian plate, in the Western Himalaya. We show that zircons of Asian affinity were deposited on the Indian plate at 54 Ma. We thus constrain terminal India–Asia collision, when both sutures north and south of the Kohistan–Ladakh Island arc were closed, to have occurred in the Western Himalaya by 54 Ma.

Crustal deformation model of the Beppu−Shimabara graben area, central Kyushu, Japan, based on inversion of three-component GNSS data in 2000–2010

The 2016 Kumamoto earthquakes, including an Mw-7 right-lateral earthquake on April 15 (UTC), occurred along faults within the Beppu−Shimabara graben in central Kyushu, Japan. Previous studies showed that the graben area was under heterogeneous stress conditions with north–south T-axes and spreading in a north–south direction. Here, we construct a detailed crustal deformation model using three-component Global Navigation Satellite System data in 2000–2010 and considering the distribution of geological fault traces in this area. Our inversion analysis suggests that the strain accumulation rate for the right-lateral seismic slip segment (corresponding to the Futagawa fault), where the largest of the 2016 Kumamoto earthquakes ruptured, was several times smaller than the other segments in the Beppu−Shimabara graben. Furthermore, we observe distinct subsidence along the Beppu−Shimabara graben. Our base model attributes the subsidence to deflation of magma reservoirs beneath volcanoes, but the observed vertical velocities are poorly fit. In order to improve the fitting results for the vertical deformation, we need more sophisticated volcano-deformation model (such as a sill-like deformation source for Mt. Aso) or graben model.

Subsidence and current strain patterns on Tenerife Island (Canary Archipelago, Spain) derived from continuous GNSS time series (2008–2015)

In this paper we present the current crustal deformation model of Tenerife Island derived from daily CGPS time series processing (2008–2015). Our results include the position time series, a global velocity estimation and the current crustal deformation on the island in terms of strain tensors. We detect a measurable subsidence of 1.5–2mm/yr. in the proximities of the Cañadas-Teide-Pico Viejo (CTPV) complex. These values are higher in the central part of the complex and could be explained by a lateral spreading of the elastic lithosphere combined with the effect of the drastic descent of the water table in the island experienced during recent decades. The results show that the Anaga massif is stable in both its horizontal and vertical components. The strain tensor analysis shows a 70nstrain/yr. E-W compression in the central complex, perpendicular to the 2004 sismo-volcanic area, and 50nstrain/yr. SW-NE extension towards the Northeast ridge. The residual velocity and strain patterns coincide with a decline in volcanic activity since the 2004 unrest.

Crustal deformation and surface kinematics after the 2010 earthquakes in Latin America

Strong earthquakes cause large changes in the station positions and velocities of the geodetic reference stations; i.e., the global ITRF (International Terrestrial Reference Frame) and its regional densifications like SIRGAS (Sistema de Referencia Geocéntrico para Las Américas) in Latin America and the Caribbean. To ensure the long-term stability of the geodetic reference frames, the transformation of station positions between different epochs requires the computation of reliable continuous surface deformation (or velocity) models. This paper presents the computation of a new continental continuous crustal deformation model for Latin America and the Caribbean inferred from GNSS (GPS+GLONASS) measurements gained after the strong earthquakes occurred in 2010 in Chile and Mexico. It is based on a multi-year velocity solution for a network of 456 continuously operating GNSS stations and covering a five years period from March 14, 2010 to April 11, 2015. This new deformation model, called VEMOS2015 (Velocity Model for SIRGAS 2015), is computed using the least square collocation (LSC) approach with empirically determined covariance functions. The result is summarised as follows: While the effects of the Baja California earthquake can be considered as local, the effects of the Maule earthquake changed the surface kinematics of a large area (between the latitudes 30°S–45°S from the Pacific to the Atlantic coasts). Before the Maule earthquake, the strain rate field in this area showed a strong west-east compression with maximum rates of about 0.40μstrain/a between latitudes 38°S and 44°S. In accordance, the deformation vectors were roughly parallel to the plate subduction direction and their magnitudes decreased with the distance from the subduction front. After the earthquake, the largest compression (0.25μstrain/a) occurs between the latitudes 37°S and 40°S with a N30°E direction. The maximum extensional strain rate (0.20–0.35μstrain/a) is observed in the Sub-Andean zone in the Patagonia south of latitude 40°S. The extensional axes rotate from a N30°E direction in the central Araucania zone to a westerly direction of N72°W in the western part of Patagonia. In the northern region of parallel 35°S, the extension is also directed to the Maule zone (S45°W) but with quite smaller rates (<0.06μstrain/a). This complex kinematics causes a large counter clockwise deformation pattern rotating around a point south of the epicentre (35.9°S, 72.7°W). The magnitude of the deformation vectors varies from 1mm/a close to the rotation point up to 22mm/a near the 2010 earthquake epicentre. The direction of the largest deformation vectors points to the epicentre. VEMOS2015 covers the region from 55°S, 110°W to 32°N, 35°W with a spatial resolution of 1°×1°. The average prediction uncertainty is ±0.6mm/a in the north-south direction and ±1.2mm/a in the east-west direction. The maximum is ±9mm/a in the Maule deformation zone while the minimum values of about ±0.1mm/a occur in the stable eastern part of the South American plate.

A possible restart of an interplate slow slip adjacent to the Tokai seismic gap in Japan

The Tokai region of Japan is known to be a seismic gap area and is expected to be the source region of the anticipated Tokai earthquake with a moment magnitude of over 8. Interplate slow slip occurred from approximately 2001 and subsided in 2005 in the area adjacent to the source region of the expected Tokai earthquake. Eight years later, the Tokai region again revealed signs of a slow slip from early 2013. This is the first evidence based on a dense Global Positioning System network that Tokai long-term slow slips repeatedly occur. Two datasets with different detrending produce similar transient crustal deformation and aseismic slip models, supporting the occurrence of the Tokai slow slip. The center of the current Tokai slow slip is near Lake Hamana, south of the center of the previous Tokai slow slip. The estimated moments, which increase at a roughly constant rate, amount to that of an earthquake with a moment magnitude of 6.6. If the ongoing Tokai slow slip subsides soon, it will suggest that there are at least two different types of slow slip events in the Tokai long-term slow slip area: that is, a large slow slip with a moment magnitude of over 7 with undulating time evolution and a small one with a moment magnitude of around 6.6 with a roughly linear time evolution. Because the Tokai slow slip changes the stress state to one more favorable for the expected Tokai earthquake, intense monitoring is going on.

A Fault‐Based Model for Crustal Deformation, Fault Slip Rates, and Off‐Fault Strain Rate in California

We invert Global Positioning System (GPS) velocity data to estimate fault slip rates in California using a fault‐based crustal deformation model with geologic constraints. The model assumes buried elastic dislocations across the region using Uniform California Earthquake Rupture Forecast Version 3 (UCERF3) fault geometries. New GPS velocity and geologic slip‐rate data were compiled by the UCERF3 deformation working group. The result of least‐squares inversion shows that the San Andreas fault slips at 19–22 mm/yr along Santa Cruz to the North Coast, 25–28 mm/yr along the central California creeping segment to the Carrizo Plain, 20–22 mm/yr along the Mojave, and 20–24 mm/yr along the Coachella to the Imperial Valley. Modeled slip rates are 7–16 mm/yr lower than the preferred geologic rates from the central California creeping section to the San Bernardino North section. For the Bartlett Springs section, fault slip rates of 7–9 mm/yr fall within the geologic bounds but are twice the preferred geologic rates. For the central and eastern Garlock, inverted slip rates of 7.5 and 4.9 mm/yr, respectively, match closely with the geologic rates. For the western Garlock, however, our result suggests a low slip rate of 1.7 mm/yr. Along the eastern California shear zone and southern Walker Lane, our model shows a cumulative slip rate of 6.2–6.9 mm/yr across its east–west transects, which is ∼1 mm/yr increase of the geologic estimates. For the off‐coast faults of central California, from Hosgri to San Gregorio, fault slips are modeled at 1–5 mm/yr, similar to the lower geologic bounds. For the off‐fault deformation, the total moment rate amounts to 0.88×1019 N·m/yr, with fast straining regions found around the Mendocino triple junction, Transverse Ranges and Garlock fault zones, Landers and Brawley seismic zones, and farther south. The overall California moment rate is 2.76×1019 N·m/yr, which is a 16% increase compared with the UCERF2 model. Online Material: Table of geological slip rates.

Heterogeneous Fault Mechanisms of the 6 October 2008 MW 6.3 Dangxiong (Tibet) Earthquake Using Interferometric Synthetic Aperture Radar Observations

Most current crustal deformation models do not account for topographic effects, crustal lateral variations, and complex fault geometries. To overcome these limitations, we apply finite element models constrained by interferometric Synthetic Aperture Radar (InSAR) images of co-seismic displacements to the 2008 Mw 6.3 Dangxiong earthquake that occurred in Yadong–Gulu rift, southern Tibet. For mountainous plateau environments, InSAR observations are advantageous for studying crustal deformation and crustal medium structure. We evaluate the effect of topography and variations in Poisson’s ratio and elastic moduli on estimation of coseismic deformation from InSAR observations. The results show that coseismic surface displacements are more sensitive to variations in Young’s modulus than to variations in topography and Poisson’s ratio. Therefore, with constant Poisson’s ratio and density, we change the Young’s modulus on each side of the fault to obtain the model that best fits the observations. This is attained when the Young’s moduli in the eastern and western sides of the fault were 2.6 × 1010 Pa and 7.8 × 1010 Pa, respectively. The result is consistent with previous field surveys that the medium on either side of the fault is different.

Estimation of the Crustal Deformation Caused by Earthquake and Its Use in Updating Published Coordinates of Geodetic Control Points - A Case Study of the 2011 Tohoku Earthquake’s Impact in South Korea

The Tohoku Earthquake, which hit Japan on March 11, 2011, was a massive magnitude 9.0 earthquake, with the earthquake itself causing damage and the resulting tsunami additionally causing enormous material and human damage. The crustal deformation at that time reached a maximum of 5.24 m in Japan, Neighboring countries South Korea and China as well as the Southeast Asian region also witnessed crustal deformation ranging from a few centimeters to a few meters. The detailed analysis in this study based on data from 72 of the sites in South Korea where GNSS CORS was installed showed that South Korea underwent heterogeneous crustal deformation from the Tohoku earthquake, with a maximum of 55.5 mm, a minimum of 9.2 mm, and an average of 22.42 mm. A crustal deformation model was developed, applied, and evaluated for accuracy in this study for a prompt revision of the survey results of the control points that were changed by the crustal deformation. The survey results were revised by applying a crustal deformation model to the 1,195 unified control points installed in South Korea prior to the Tohoku earthquake. The comparison of these 1,195 points with their new survey results showed that the RMSE decreased from 14.1 to 3.4 mm and that the maximum result difference declined from 39 to 10 mm. Revision of the survey results of the control points using the crustal deformation model is deemed very useful considering that the accuracy of the survey results of the unified control points in South Korea is 3 cm.

The Devil truly is in the detail. A cautionary note on computational determinism: Implications for structural geology numerical codes and interpretation of their results

The widespread use of numerical modeling codes in structural geology, particularly in forward modeling of crustal deformation, has brought valuable insight into many processes such as fault initiation and propagation, fold growth, and orogenic wedge development. Whether commercial, open source, or the result of an individual researcher’s endeavor, such numerical codes increasingly rely on advanced compiler optimizations and/or parallelization techniques. This is done to maximize performance on today’s multicore processors and thus achieve tractable model runtimes. However, such speed and productivity can come at a price. Many optimization and parallelization techniques used do indeed produce remarkable runtime speedups, but at the expense of determinism and reproducibility. Most researchers are only tangentially aware of these issues. I have aimed to explain why numerical model runs with identical sets of initial and boundary conditions can potentially produce different results and thus, sensu stricto, be nondeterministic. I have developed some solutions and guidelines for maintaining determinism and evaluated these issues using a discrete element code of upper crustal deformation. Implications for the interpretation and use of such model results in structural geology were also evaluated.

The crustal thickness of NE Tibet and its implication for crustal shortening

The crustal deformation model for NE Tibet is key to understanding the outward growth of the plateau, especially along its northern front. This study describes receiver function images of the Moho beneath NE Tibet, as calculated from teleseismic data recorded by regional seismic networks. Moho depth from these images, coupled with results from previous wide-angle reflection/refraction studies (WARR), allowed crustal thickness estimates along several profiles. Crustal shortening was estimated by restoring the present day thickened crust to its assumed initial crustal thickness. Our results show a relatively large amount of crustal shortening (250–350km) at an orientation of N30°E in the central part of NE Tibet. This indicates that prior to shortening, the southern edge of Asia lay 300–400km north of the location indicated by previous S-wave receiver function studies. This discrepancy may result from southward subduction of a segment of Asia's lower-crust beneath central Tibet. It could also arise from crustal thickening predominantly caused by upper-crustal shortening, provided that delamination of eclogitized mafic lower-crust and erosion have not significantly reduced crustal volume.

InSAR observations and models of crustal deformation due to a glacial surge in Iceland

Surges are common at all the major ice caps in Iceland. Ice masses of gigatons may shift from the upper part of the outlet glacier towards the terminus in a few months, advancing the glacier front by up to several kilometres. The advancing ice front may be up to 100 m thick, increasing the load on crustal rocks correspondingly. We use the observed change in crustal loading during a surge of the western part of the Vatnajokull ice cap, Iceland, during 1993–1995 and the corresponding elastic crustal deformation, surveyed with interferometric synthetic aperture radar, to investigate the material properties of the solid Earth in this region. Crustal subsidence due to the surge reaches ∼75mm at the edge of the Siðujokull outlet glacier. This signal is mixed with a broad uplift signal of ∼12 mm/yr, relative to our reference area, caused by the ongoing retreat of Vatnajokull in response to climate change. We disentangle the two signals by linear inversion. Finite element modelling is used to investigate the elastic Earth response of the surge, as well as to confirm that no significant viscoelastic deformation occurred as a consequence of the surge. The modelling leads to estimates of the Young’s modulus and Poisson’s ratio of the underlying Earth. Comparison between the observed and modelled deformation fields is made using a Bayesian approach that yields the estimate of a probability distribution for each of the free parameters. Residuals indicate a good agreement between models and observations. One-layer elastic models result in a Young’s modulus of 43.2–49.7 GPa (95 per cent confidence) and Poisson’s ratio of 0–0.27, after removal of outliers. Our preferred model, with two elastic layers, provides a better fit to the whole surge signal. This model consists of a 1-km-thick upper layer with an average Young’s modulus of 12.9–15.3 GPa and Poisson’s ratio of 0.17, overlying a layer with an average Young’s modulus of 67.3–81.9 GPa and Poisson’s ratio of 0.25.

Crustal velocity and strain rate fields in the Balearic Islands based on continuous GPS time series from the XGAIB network (2010–2013)

In this paper, we present a first estimation, using the GIPSY-OASIS software, of the crustal velocity and strain rate fields in the Balearic Islands (Spain), based on continuous GPS observations from the XGAIB network spanning the period 2010–2013. The XGAIB network consists of nine permanent, widely distributed stations that have operated continuously since 2010. In this paper, we describe the XGAIB network and the CGPS data processing and present our principle results in terms of the position time series and velocities of all of the sites, which were observed for more than three and a half years. In addition, strain tensors were estimated from the velocity field to obtain the first realistic crustal deformation model of the archipelago. The strains exhibit gradual variation across the Balearic Islands, from WNW–ESE extension in the southwest (Ibiza and Formentera) to NW–SE compression in the northeast (Menorca). These results constitute an advance in our knowledge of the tectonics of the western Mediterranean region.

Influence of fault connectivity on slip rates in southern California: Potential impact on discrepancies between geodetic derived and geologic slip rates

AbstractAlong the San Bernardino strand of the San Andreas fault (SAF) and across the eastern California shear zone (ECSZ), geologic slip rates differ from those inverted from geodetic measurements, which may partly be due to inaccurate fault connectivity within geodetic models. We employ three‐dimensional models that are mechanically compatible with long‐term plate motion to simulate both fault slip rates and interseismic surface deformation. We compare results from fault networks that follow mapped geologic traces and resemble those used in block model inversions, which connect the San Jacinto fault to the SAF near Cajon Pass and connect distinct faults within the ECSZ. The connection of the SAF with the San Jacinto fault decreases strike‐slip rates along the SAF by up to 10% and increases strike‐slip rates along the San Jacinto fault by up to 16%; however, slip rate changes are still within the large geologic ranges along the SAF. The insensitivity of interseismic surface velocities near Cajon Pass to fault connection suggests that inverse models may utilize both an incorrect fault geometry and slip rate and still provide an excellent fit to interseismic geodetic data. Similarly, connection of faults within the ECSZ produces 36% greater cumulative strike‐slip rates but less than 17% increase in interseismic velocity. When using overconnected models to invert GPS for slip rates, the reduced off‐fault deformation within the models can lead to overprediction of slip rates. While the nature of fault intersections at depth remains enigmatic, fault geometries should be chosen with caution in crustal deformation models.

Kinematic model of crustal deformation of Fenwei basin, China based on GPS observations

Using high precision GPS data for the period of 1999–2007 from the China Crustal Movement Observation Network, we have constructed a plate kinematic model of crustal deformation of Fenwei basin, China. We have examined different kinematic models that can fit the horizontal crustal deformation of the Fenwei basin using three steps of testing. The first step is to carry out unbiasedness and efficiency tests of various models. The second step is to conduct significance tests of strain parameters of the models. The third step is to examine whether strain parameters can fully represent the deformation characteristics of the 11 tectonic blocks over the Fenwei basin. Our results show that the degree of rigidity at the Ordos, Hetao, Yinshan and South China blocks is significant at the 95% confidence level, indicating the crustal deformation of these blocks can be represented by a rigid block model without the need to consider differential deformation within blocks. We have demonstrated that homogeneous strain condition is suitable for the Yinchuan basin but not for other 6 blocks. Therefore, inhomogeneous strains within blocks should be considered when establishing the crustal deformation model for these blocks. We have also tested that not all of the quadratic terms of strain parameters are needed for the Yuncheng-Linfen block. Therefore, four kinds of elastic kinematic models that can best represent the detailed deformation characteristics of the 11 blocks of Fenwei basin are finally obtained. Based on the established model, we have shown that the current tectonic strain feature of the Fenwei basin is mainly characterized by tensile strain in the NW–SE direction, and the boundaries betweem the Ganqing and Ordos blocks and the Shanxi graben possess the maximum shear strain. A comparison between our results and past geological and geophysical investigations further confirms that the model established in this paper is reasonable.