The Mediterranean Basin sits in the western section of the Alpine-Himalayan seismic belt, which was formed by the closure of the Tethys Sea (Bozkurt, 2001; Jackson & McKenzie, 1984; Taymaz et al., 1991). The eastern Mediterranean region is the most seismically active region in Europe due to the rapid movement of small tectonic blocks (Faccenna & Becker, 2010; Le Pichon & Kreemer, 2010; Malinverno & Ryan, 1986; Nocquet, 2012). The indentation of the Arabian plate, the tectonic escape of Anatolia, and the opening of the Aegean Sea accompanied by slab rollback at the Hellenic Trench orchestrate a large-scale rotation accommodated by major transform faults (Barbot & Weiss, 2021; Faccenna et al., 2014; Jolivet et al., 2013). The indentation of the Arabian plate forms a triple junction with slip partitioning among the North Anatolian Fault (NAF), the East Anatolian Fault (EAF), and the Main Recent Fault (Reilinger et al., 2006; Talebian & Jackson, 2002; Vernant et al., 2004). The NAF is a 1,200 km-long, mature, right-lateral strike-slip fault extending from the Karliova triple junction to the Sea of Marmara (N. N. Ambraseys, 1970; Armijo et al., 1999; Güvercin et al., 2022; Hubert-Ferrari et al., 2002; Le Pichon et al., 2016). The EAF, a conjugate, 300 km-long left-lateral fault, extends southwards and branches out diffusely to the Dead Sea Fault (DSF) and the Cyprus Arc to the southwest (Duman & Emre, 2013). The EAF connects multiple segments with a low long-term slip rate (Aktug et al., 2016; Cavalié & Jónsson, 2014) separated by major releasing bends and step-overs (Duman & Emre, 2013; Güvercin et al., 2022), making it relatively immature compared to the NAF and other continental strike-slip faults (Wesnousky, 1988). Farther south, the left-lateral DSF is the boundary fault accommodating the northward migration of the Arabian plate (Garfunkel et al., 1981; Hamiel & Piatibratova, 2021).

The motion of these tectonic plates is modulated by the frictional resistance of faults in the brittle crust, leading to seismic cycles. The NAF ruptured in a long sequence of earthquakes in the 20^th century, starting with the 1939 Erzincan earthquake, and ending with the 1999 Mw 7.9 Izmit and Mw 7.2 Düzce earthquakes near Istanbul in Western Turkey (N. N. Ambraseys, 1970; Bohnhoff et al., 2016; Hartleb et al., 2003). The EAF featured several notable earthquakes during the last century, with the 1905 Mw 6.8, the 1971 Mw 6.7, the 2010 Mw 6.1, and the 2020 Mw 6.8 earthquakes, but the section south of Elazığ has remained locked for more than a century (Duman & Emre, 2013; Hubert-Ferrari et al., 2020). Previous large earthquakes in this section include the 1114 M 6.9, 1795 Mw 7.0, 1872 Mw 7.2, and 1893 Mw 7.1 ruptures (N. Ambraseys, 2009; Güvercin et al., 2022), all bounded by major (releasing) fault bends (Duman & Emre, 2013). Since then, the fault has remained mostly locked, slowly accumulating stress, until it finally unzipped in a continuous rupture in 2023, generating a powerful Mw 7.8 earthquake (Dal Zilio & Ampuero, 2023; Melgar et al., 2023).

The February 6, 2023 Kahramanmaraş earthquake, the largest seismic event in Turkey since 1939, ruptured the south-western segments of the EAF (Figure 1). The powerful mainshock initiated a long aftershock sequence including the Mw 7.6 Elbistan earthquake just 9 hours later on the east-west trending left-lateral Çardak fault in the East Anatolian Fault Zone (EAFZ) and the February 20, Uzunba Mw 6.4 aftershock near Antakya (hereafter, called the Antakya aftershock), where the EAF bifurcates offshore towards the Cyprus arc. Such a sequence of large earthquakes on nearby faults within hours of each other has no equivalent in a continental setting, especially considering the similar source mechanisms. The mainshock and its large aftershocks destroyed or severely damaged some 160,000 buildings, killed more than 50,000 people, displaced 200,000 more, and affected 14 million people across Turkey and Syria.

In this study, we combine spaceborne geodesy and seismological data to constrain the slip distribution of the 2023 Kahramanmaraş earthquake sequence to address first-order questions regarding the mechanisms of rupture propagation and arrest in the EAFZ. We constrain the near-field deformation of the February 6 Mw 7.8 and Mw 7.6 earthquakes using cross-correlation of Sentinel-2 optical data (ForM@Ter, 2023) and synthetic aperture radar (SAR) images, and Advanced Land Observing Satellite (ALOS) data before and after the February 6 earthquakes. We use high-rate Global Navigation Satellite Systems (GNSS) data to constrain the surface displacement caused by these earthquakes within a 200 km radius. We ensure that the fault geometry at depth follows the distribution of relocated aftershocks (Lomax, 2023). The mainshock rupture is bounded to the south by the February 20, Mw 6.4 Antakya earthquake and the transition between the EAF and Antakya Fault that propagates into the Mediterranean Basin (Figure 2). We constrain the rupture of the Mw 6.4 aftershock using synthetic aperture radar interferometry (InSAR). The mainshock rupture stopped south of the Pütürge segment some 30 km south of the 2020 Mw 6.8 Elâziğ earthquake (Konca et al., 2021; Pousse-Beltran, Nissen, et al., 2020; Ragon et al., 2021), leaving a potential seismic gap in the intervening region.

The coseismic slip of these earthquakes illuminates some important characteristics of the brittle crust in the EAFZ. Along the EAF, the slip distribution is characterized by a shallow slip deficit, a maximum coseismic slip of 8 m between 3 and 7 km depth, and a bottom depth of 18 km depth — presumably including much afterslip. Along the strike direction, coseismic slip is maximum at the center of planar segments and tapers at the segment boundaries. The small-magnitude aftershocks cluster at the segment boundaries and at the periphery of regions of high coseismic slip. Along the Çardak fault, the coseismic slip of the Mw 7.6 aftershock is relatively uniform with 11 m from the surface to 7 km depth, vanishing at 12 km depth.

We constrain the slip distribution of the Kahramanmaraş and the Elbistan earthquakes using space-geodetic data from the Sentinel-1 and Sentinel-2 satellites and from GNSS measurements. Sentinel-1 SAR provides amplitude and phase images of the crustal deformation surrounding the earthquakes. Although the phase measurements are more sensitive, they are sometimes unavailable near the fault trace due to decorrelation. In this case, the cross-correlation of amplitude data provides key constraints for the near-field surface displacements and fault slip. Cross-correlation of optical Sentinel-2 data provides similar constraints. Unlike the space geodetic data, the temporal resolution of the GNSS data allows us to constrain the displacements caused by individual earthquakes. For the Antakya Mw 6.4 aftershock, we make use of the greater sensitivity of the Sentinel-1 SAR phase and constrain the slip distribution with the inversion of the Sentinel-1 interferograms. Below, we describe the data processing to constrain crustal deformation.

The Mw 7.8 mainshock initiated on the Narlı Fault Zone that bounds the Narlı basin, north of the Karasu trough (Figures 1 and 2). The rupture continued along the East Anatolian Fault, propagating bilaterally into the Amanos segment to the south and into the Pazarcık and Erkenek segments to the north (Melgar et al., 2023). The surface rupture stopped just northeast of the Yarpuzlu restraining bend. There is no visible surface break along the Pütürge segment even though aftershocks extend to the southern limit of the 2020 Mw 6.8 Elazığ rupture.

The Mw 7.6 aftershock nucleated in the middle of the Çardak Fault and propagated westward to the Savrun Fault and eastward across the so-called Nurhak complexity (Duman & Emre, 2013) along an immature fault between the Malatya and the Sürgu faults (Melgar et al., 2023). The Mw 7.6 aftershock triggered a sequence of additional aftershocks including normal faulting earthquakes near the Savrun Fault (Figure 1). The aftershocks cluster north of the Çardak Fault, indicating a north dipping fault.

We constrain the trace of the rupture surface of the February 6 earthquakes by examination of the displacement discontinuity in the near-field optical and SAR amplitude pixel-tracking, and InSAR data (Figures 3, S2, and 5). There is no indication of slip on the Sürgu fault connecting the Çardak fault to the EAF. The Mw 7.8 mainshock and the Mw 7.6 aftershock occurred on disconnected faults. The long streak of seismicity east of the Karasu trough and south of the Narlı Basin is not associated with detectable surface displacements.

We simplify the geometry by considering 8 and 5 segments of uniform orientation for the Mw 7.8 mainshock and the Mw 7.6 aftershock, respectively (Table 1). We extend the fault planes to a depth of 20 km running through the relocated seismicity (Lomax, 2023). For the Mw 7.8 mainshock, we extend the model to include the Pütürge segment to test whether any blind slip occurred north of the surface rupture. We use vertical faults for the Mw 7.8 mainshock, which is sufficient to follow the distribution of aftershocks. However, small variations of dip of 15 are admissible.

For the Mw 7.6 aftershock, we include a normal fault at the western end of the Çardak Fault to capture a displacement discontinuity perpendicular to the main trace compatible with the concentration of aftershock with a normal faulting focal mechanism (Figure 1). We assume a dip angle of 60 for the Çardak Fault, compatible with the distribution of aftershocks in this location. We use a dip angle of 50 for the normal fault south of the Savrun Fault, also compatible with the distribution of aftershocks.

We discretize the fault planes with  km patches and use the Green’s function relating the fault strike-slip and dip-slip components to surface displacement for an elastic half-space (Okada, 1992). To reduce the number of data points used in finite-source modeling, we downsample the observations using a quadtree (Fialko, 2004; e.g., Jónsson et al., 2002). We invert for the slip distribution using regularized least-squares by imposing a smooth distribution of slip enforced by a Laplacian operator (Huiskamp, 1991). We use an L-curve (Figure S3) to estimate the optimal smoothing constraints (Aster et al., 2012). The resolution of the inversion deteriorates rapidly with depth, with an average of 45% in the first 2 km dropping to 1-3% at 6-7 km depth, as is typical with geodetic constraints (Barbot, Fialko, et al., 2008; Barbot et al., 2013; Sathiakumar et al., 2017). The inferred slip distribution represents a spatial average that masks short-wavelength variations. However, the bulk features of the model, such as the along-strike variations, can be determined more reliably.

The comparison between the observations and the forward model associated with the finite-source inversion is shown in Figures S4 and S5. There are high-frequency residuals along the fault traces (e.g., Figures S4c,f) due to the simplifying assumption of a piecewise linear fault trace. In reality, the faults run through numerous bends and jogs at fine scales that are not captured by our geometrically simple model. There are one-sided residuals in the near field of the Çardak fault and the central EAF in the Sentinel-1 DT21 range offset (Figure S4c) that would imply a different fault dip angle. However, the other datasets are explained well in the same location.

Overall, there is a good agreement between the various datasets considered. The model explains the GNSS displacements for the Mw 7.8 mainshock and Mw 7.6 aftershock particularly well, with a variance reduction of 85% and 97%, respectively (Figure S4a-f). The model variance reduction for the Sentinel-1 pixel-tracking data ranges from 37 to 61% due to a large background noise that is common for this type of data (Leprince et al., 2007). The variance reduction for the ALOS-2 interferograms is 73% and 80% for the ascending and descending tracks, respectively. The variance reduction for the Sentinel-2 optical data is only 12%, due to large measurement errors associated with cloud and snow cover (Figure S6). However, these data are useful to constrain the distribution of shallow fault slip.

The resulting slip distributions for the Mw 7.8 mainshock and the Mw 7.6 aftershock are shown in Figure 6. Along the EAF, coseismic slip is maximum between 3 and 7 km depth, tapering off from 8 to 14 km depth. Fault slip is mostly left-lateral with small changes of dip near the surface. Assuming a uniform shear modulus of 30 GPa, we find a geodetic moment of  Nm corresponding to Mw=7.8. The slip distribution is highly segmented and relatively uniform within segments of uniform strike angle, revealing asperities of large slip within the South Amanos, North Amanos, Pazarcık, and Erkenek segments. Slip is the largest along the Pazarcık segment, reaching a maximum of 8 m. Along the South Amanos segment, slip reaches 4 m, tapering off to the southwest. To the northeast, the surface rupture shows a bifurcation to the İzci segment. However, this is not accompanied by much fault slip at depth.

The rupture of the Mw 7.6 aftershock is more compact, mostly confined to the Çardak fault with a maximum slip of 12 m from the surface to 7 km depth. The slip tapers off from 8 to 12 km, shallower than along the EAF. Slip along the northeast-striking Gök Hill and Söğüt segments between the Malatya and Sürgü faults is limited to at most 5 m. Slip on the south-striking Yeşilköy normal fault reaches 2 m. Assuming a uniform shear modulus of 30 GPa, we find a geodetic moment of  Nm corresponding to Mw=7.6.

We now examine the southern termination of the mainshock rupture, which is associated with a large cluster of aftershocks. Specifically, we focus on the crustal deformation caused by the February 20, 2023, Mw 6.4 aftershock near Antakya that was captured by Sentinel-1 data. Focusing on the small footprint most affected by the Mw 6.4 aftershock, we determine the position, orientation, dimension, and slip vector based on the InSAR data in a Bayesian inversion (Bagnardi & Hooper, 2018; Javed et al., 2022). These data can be explained well by a fault striking 237N with a dip angle of 55. The fault orientation falls within the large cloud of aftershock hypocenters and aligns well with the Antakya Fault that runs toward the Cyprus Arc.

Using the inferred geometry, we invert for a finite slip distribution applying a non-negative least square inversion (Jónsson et al., 2002), with a discretization of the fault into km patches. Slip is allowed to have along-strike and down-dip components. We use the L-curve (Aster et al., 2012) to resolve the trade-off between misfit and roughness (Figure S8). The data used for the inversion are defined by the dashed frame in Figure 4. We use the ascending and descending interferograms jointly to constrain the slip distribution. The rupture extends along the strike with a length of 25 km, and a downdip distance of 25 km. The maximum slip of 0.93 m occurs at a depth of 8.3 km, with a rake of -12, corresponding to dominantly left-lateral slip, with the area affected by greater slip extending down-dip towards the northeast (Figure 6). The comparison between the Sentinel-1 observations for tracks AT14 and DT21 and the forward model for the Mw 6.4 Antakya aftershock is shown in Figure S7.

The slip distribution of the Kahramanmaraş seismic sequence brings light into the processes of earthquake rupture propagation and arrest and the properties of the seismogenic zone in the continental crust. Even though the rupture reaches the surface in many locations, the slip distribution is overall characterized by a shallow slip deficit (Figure 7), similar to many large earthquakes in the continental crust (Fialko et al., 2005; Qiu et al., 2020; Wei et al., 2015). For the EAF, the slip reaches a maximum between 3 and 7 km depth. While the maximum slip reaches 8 m at depth, the surface slip peaks only at 6 m, indicating a 25% slip deficit. The coseismic slip of the 2020 Mw 6.8 Elazığ earthquake is even more confined, leading to a 60% slip deficit (Figure 7f). The peak of 12 m of slip at 4 km depth on the Çardak fault leads to a 25% slip deficit as well (Figure 7e). For the system to conserve mass, slip must accumulate at different parts of the seismic cycle as afterslip (Barbot, Fialko, & Bock, 2009; Rollins et al., 2015; Rousset et al., 2012; Tang et al., 2020) or more slowly during the interseismic phase (Barbot et al., 2013; Bilham et al., 2016; Cetin et al., 2014; Kaneko et al., 2013; Rollins et al., 2018), or by straining a wider region surrounding the fault. It is possible that much of the shallow slip occurs aseismically during the intervening days between the mainshock and the remote-sensing data acquisition.

The shallow slip deficit is broadly compatible with the thermal activation of rate-, state-, and temperature-dependent friction in the continental crust (Barbot, 2019a; L. Wang & Barbot, 2020). Most rocks exhibit steady-state velocity-strengthening behavior at room temperature, transitioning to velocity-weakening at temperatures relevant to the mid-crust, for example, pyroxene (Tian & He, 2019), amphibole (Liu & He, 2020), blueschist (Sawai et al., 2016), granite (Mitchell et al., 2016), serpentinite (Takahashi et al., 2011), biotite (Lu & He, 2014, 2018), shale (An et al., 2020), and samples of mixed composition taken from natural faults (Boulton et al., 2014; Hartog et al., 2021; Rabinowitz et al., 2018; Valdez II et al., 2019). The shallow velocity-strengthening layer can also be caused by the presence of granular material associated with sediments or a damage zone. Another explanation is the broadening of the deformation zone surrounding the fault, such as a flower structure or distributed plasticity (Barbot, Fialko, et al., 2008, 2009; Cochran et al., 2009; Fialko et al., 2002; Hamiel & Fialko, 2007). However, the spatial resolution of the geodetic data considered is limited to 2 km, and we cannot resolve the distribution of deformation below this length scale.

The distribution of seismicity spans a markedly greater depth range than coseismic slip, extending down to at least 20 km depth in this region (Bulut et al., 2012; Pousse-Beltran, Socquet, et al., 2020). It is therefore useful to discriminate the seismic layer from the seismogenic zone defined as the depth of nucleation and initial propagation of large earthquakes. The seismic layer represents the maximum depth of micro-seismicity (Nazareth & Hauksson, 2004; e.g., Shearer et al., 2005), which is caused by small-scale heterogeneities in composition, fluid pressure, normal stress, texture, and fault orientation. Ultimately, the seismic layer may terminate at the brittle-ductile transition. In contrast, the seismogenic zone is controlled by the stability of frictional sliding (Blanpied et al., 1995), which may be entirely controlled by the distribution of frictional properties (Barbot, 2019b; Rice & Ruina, 1983; Rubin & Ampuero, 2005; Ruina, 1983; B. Wang & Barbot, 2023; L. Wang & Barbot, 2020).

The coseismic slip distribution constrains the depth of the seismogenic zone. However, during the rupture of large earthquakes, coseismic slip propagates into the velocity-strengthening domains due to the concentration of static and dynamic stresses near the free surface (e.g., Barbot et al., 2012; Jiang et al., 2022; Jiang & Lapusta, 2016) and is affected by enhanced weakening mechanisms (Di Toro et al., 2011). As a result, the unstable-weakening region that forms the seismogenic zone is presumably much narrower than the depth extent of coseismic slip.

The distribution of aftershock hypocenters is shown in cross-section in Figure 7 where the seismicity in the surrounding 20 km of the EAF and the Çardak fault is shown for the Mw 7.8 mainshock and the Mw 7.6 aftershock, respectively. Despite uncertainties in hypocenter location due to a sparse seismic network, the distribution of aftershocks exhibits a remarkable complementarity with the distribution of coseismic slip, surrounding the regions of high slip, but also concentrating at segment boundaries. Additional aftershocks extend the ruptured faults outwards, past the rupture tip. This is the case near Antakya, where seismicity propagates towards the Cyprus Arc, east of the Karasu trough, where seismicity propagates towards the Dead Sea Fault, and north of the Sürgü fault, creating a new fault structure running parallel to the EAF.

The complementarity of the distribution of coseismic slip and aftershocks is another indication of the depth extent of the seismogenic zone. For the Mw 7.8 mainshock there is a dearth of aftershocks between 2 and 10 km depth. For the Mw 7.6 aftershock, the seismicity is much less intense between 2 and 8 km depth. The lateral variations in the depth extent of aftershocks may be associated with differences in hydrothermal conditions, such as geothermal gradients and pore fluid pressure, or with different compositions of the fault zones. We speculate that the seismogenic zone extends from 4 to 10 km depth in this region and that the coseismic slip that occurred outside these bounds took place in a nominally rate-strengthening region of the fault. Coseismic slip commonly propagates in regions of stable sliding because of dynamic effects (Barbot et al., 2012; Barbot, 2019b; Nanjundiah et al., 2020; Noda & Lapusta, 2013; Salman et al., 2017; B. Wang & Barbot, 2023).

The distribution of coseismic slip reveals asperities of large slip centered along the South Amanos, North Amanos, Pazarcık, and Erkenek segment separated by major releasing bends and step-overs (Duman & Emre, 2013). These segments ruptured in smaller-magnitude earthquakes in the last millennia. The Amanos segment hosted an Mw=7.5 earthquake in 521. The Pazarcık segment ruptured previously in 1513 in a Mw=7.4 earthquake. The Erkenek segment ruptured with a Mw=7.1 earthquake in 1893. Although all these segments ruptured in a single event during the Mw 7.8 mainshock, the waxing and waning of coseismic slip along the strike direction follows the same segmentation, with tapering of fault slip near segment boundaries. This behavior is compatible with the start-stop control of fault bends and morphological gradients on seismicity (Qiu et al., 2016; Sathiakumar & Barbot, 2021).

A somewhat surprising behavior of the Kahramanmaraş earthquake sequence is the rupture of faults with the same sense of motion — left-lateral strike-slip — despite the high angle between the Çardak Fault and the Pazarcık-Erkenek segment that hosted much coseismic slip. Recent strike-slip earthquakes on oblique faults, such as the 2012 Mw 8.6 Indian Ocean (Masuti et al., 2016; Wei et al., 2013) or the 2019 Mw 7.2 Ridgecrest (K. Chen et al., 2020; Qiu et al., 2020) earthquakes occurred on conjugate faults, i.e., one being dextral while the other is sinistral. The activation of faults with the same sense of motion is not uncommon within the context of escape tectonics that operates in Anatolia. For example, the oblique Altyn Tagh Fault and the Kunlun Fault in Tibet accommodate the extrusion of southern Tibet.

A remaining question is how the Kahramanmaraş earthquake will affect future seismic unrest in the region. Of particular concern is the potential triggering of large earthquakes along the DSF system. However, the distribution of aftershocks and the fault orientation of the Mw 6.4 aftershock indicate propagation of seismic unrest toward the Cyprus Arc (Figures 1, 2, and 6). Nevertheless, intense seismicity concentrates along the eastern side of the Karasu trough, running parallel to the Amanos segment in the direction of the DSF. Hence, the potential of a southward propagation of seismicity is not entirely excluded.

More alarmingly, the slip distribution indicates a large remaining seismic gap in the Pütürge segment that separates the 2023 Mw 7.8 mainshock rupture and the fault area involved in the 2020 Mw 6.8 Elazığ earthquake (Figure 7b). The aftershock distribution connects the two ruptures between 10 and 20 km depth, leaving a 40 km-long seismic gap between the surface and 10 km depth. This area is similar to the 2020 rupture. Hence, we raise concern for the possibility of another Mw 6.8 earthquake to occur in the Pütürge segment of the EAF. Analysis of geodetic data across the Pütürge and Palu segment of the EAF indicate high interseismic coupling south of the 2020 Elazığ rupture (Bletery et al., 2020). Dedicated instrumentation is necessary to monitor the fault behavior in this region.

Remote sensing data provide great insights into the 2023 Kahramanmaraş earthquake sequence, including the extent of the surface rupture and the distribution of coseismic slip along various segments of the EAF and Çardak fault during the Mw 7.8 mainshock and the Mw 7.6 aftershock. The mainshock ruptured the Amanos, Pazarcık, and Erkenek segments propagating across fault bends and releasing step-overs. The southward rupture termination was caused by the diffuse termination of the EAF as it bifurcates into the Antakya Fault and the DSF. The second largest aftershock, the Antakya Mw 6.4 earthquake extends the rupture along the Antakya Fault toward the Mediterranean Basin, alleviating the risk of triggering large earthquakes on the DSF. To the north, the rupture propagation was arrested by the Yarpuzlu releasing bend at the southern boundary of the Pütürge segment of the EAF, leaving a 40 km-long seismic gap to the rupture area of the 2020 Mw 6.8 Elazığ earthquake. The Pütürge segment must be instrumented to assess its seismic potential.

The Mw 7.6 Elbistan aftershock ruptured the nearby Çardak and Savrun faults and a previously unidentified fault situated across the Nurhak complexity between the Sürgü Fault and the Malatya Fault. The Mw 7.8 mainshock and the Mw 7.6 aftershock share the same sense of motion — left-lateral strike-slip faulting — despite markedly different fault orientations. The distribution of coseismic slip for both events highlights a pronounced shallow slip deficit and a complementarity with the aftershock distribution. These observations provide constraints on the depth of the seismogenic zone, defined as the area where large earthquakes nucleate and propagate. The depth distributions of aftershocks and of coseismic slip indicate an unstable-weakening region between 4 and 10 km depth. The Kahramanmaraş earthquake sequence reminds us of the devastating potential of immature strike-slip faults.

We are grateful for the constructive reviews of Romain Jolivet and the additional comments from the editors Edwin Nissen and Stephen Hicks. SB is supported in part by the National Science Foundation under award number EAR-1848192. YH is supported in part by the Israel Science Foundation, grant number ISF 2091/20. MTJ acknowledges funding of the PhD grant through the Prof. Maria Zadro legacy to the University of Trieste. CB acknowledges funding from MIUR-PRIN.

The supplementary information (Figures S1-S8 and Tables S1-S2) can be found at https://doi.org/10.5281/zenodo.7747846.

There are no competing interests.

The Sentinel-1 SAR data and Sentinel-2 optical data are provided by the European Space Agency (https://scihub.copernicus.eu) and are additionally distributed by the Alaska Satellite Facility (https://asf.alaska.edu/how-to/data-tools). The Advanced Land Observation Satellite‐2 (ALOS‐2) SAR data used in this work are copyright Japan Aerospace Exploration Agency (JAXA) and are open accessed at https://www.eorc.jaxa.jp/ALOS/en/dataset/alos_open_and_free_e.htm. The aftershock dataset is available at https://zenodo.org/record/7699882#.ZAjBfuzMI-Q. The Sentinel-2 cross-correlation of optical imagery is at http://doi.data-terra.u-strasbg.fr/GDM_OPT_Turkey_Syria/. The GNSS offsets are available in Tables S1 and S2. The slip distributions of the Mw 7.8 Kahramanmaraş mainshock, Mw 7.6 Elbistan aftershock, Mw 6.4 Antakya aftershock, and of the 2020 Mw 6.8 Elazığ earthquake can be found at https://doi.org/10.5281/zenodo.7747846.

Conceptualization: people. Methodology: people. Software: people. Validation: people. Formal Analysis: Name Firstauthor, Name Secondauthor. Investigation: people. Resources: people. Sentinel-1 and ALOS-2 processing: H. Luo and T. Wang. Raw GNSS data: G. Gurbuz. GNSS processing: Y. Hamiel and O. Piatibratova. Additional Sentinel-1 processing and modeling: M. T. Javed and C. Braitenberg. Numerical modeling and visualization: S. Barbot. Original draft: All authors. Writing - Review \& Editing: people. Visualization: people. Supervision: people. Project administration: people. Funding acquisition: people.