Hybrid attenuation model for estimation of peak ground accelerations in the Kutch region, India

The Kutch region of Gujarat in India is the locale of one of the most devastating earthquake of magnitude (M _w) 7.7, which occurred on January 26, 2001. Though, the region is considered as seismically active region, very few strong motion records are available in this region. First part of this paper uses available data of strong motion earthquakes recorded in this region between 2006 and 2008 years to prepare attenuation relation. The developed attenuation relation is further used to prepare synthetic strong motion records of large magnitude earthquakes using semiempirical simulation technique. Semiempirical simulation technique uses attenuation relation to simulate strong ground motion records of any target earthquake. The database of peak ground acceleration obtained from simulated records is used together with database of peak ground acceleration obtained from observed record to develop following hybrid attenuation model of wide applicability in the Kutch region: $$ \begin{aligned} \ln \left( {\text{PGA}} \right) & = - 2.56 + 1.17 \, M_{\text{w}} - \, 0.015R - 0.0001\ln \left( {E + 15} \right) \\ &\quad 3.0 \le M_{\text{w}} \le 8.2;\quad 12 \le R \le 120;\quad {\text{std}} . {\text{ dev}}.(\sigma ): \pm 0.5 \\ \end{aligned} $$ ln ( PGA ) = ? 2.56 + 1.17 M w ? 0.015 R ? 0.0001 ln ( E + 15 ) 3.0 ≤ M w ≤ 8.2 ; 12 ≤ R ≤ 120 ; std . dev . ( σ ) : ± 0.5 In the above equation, PGA is maximum horizontal ground acceleration in gal, M _w is moment magnitude of earthquake, R is hypocentral distance, and E is epicentral distance in km. The standard deviation of residual of error in this relation is 0.5. This relation is compared with other available relations in this region, and it is seen that developed relation gives minimum root mean square error in comparison with observed and calculated peak ground acceleration from same data set. The applicability of developed relation is further checked by testing it with the observed peak ground acceleration from earthquakes of magnitude (M _w), 3.6, 4.0, 4.4, and 7.7, respectively, which are not included in the database used for regression analysis. The comparison demonstrates the efficacy of developed hybrid attenuation model for calculating peak ground acceleration values in the Kutch region.     

Macroseismic field of the March 4, 1977 Vrancea earthquake

The macroseismic field of the Vrancea earthquake of March 4, 1977, characterized by the following parameters : H = 19h 21m 56s, ø = 45.8°N, γ = 26.8° E, h = 95 Km, M = 7.2, I = VIIIMSK has been analyzed. The following problems were studied : area and shape of the isoseismals of intensity III–VIII ; elongation of the isoseismal ellipses and decrease of intensity with distance. The results confirm our previous studies (Radu and Apopei, 1978) of strong intermediate earthquakes, but render evidence for some peculiarities in the seismic intensity attenuation as well.     

Soil liquefaction potential induced by the andalusian earthquake of 25 December 1884

On 25 December 1884, an earthquake of epicentral intensityI ₀ = IX in the MSK scale caused great damage in a large area in the provinces of Granada and Málaga, in the south of Spain. The reports of the Spanish, Italian and French Commissions that studied the earthquake described ground phenomena in seven different sites which can be identified as soil liquefaction.By means of dynamic penetration tests carried out in the above sites, the corresponding soil profiles (based on SPT data and water table depth) were established, and the occurrence of liquefaction was proved in five out of seven of these sites. Also, the intensities at such locations and the magnitude of the earthquake were estimated.From the geotechnical data and the cyclic stress ratio induced by the earthquake, liquefaction conditions were confirmed in all the five sites which presumably liquefied. Then, possible values of the minimum ground surface accelerations necessary for the onset of liquefaction at each location were calculated. The results obtained were completed with data reported in six liquefaction case studies from Japan and the United States, from which design charts relating soil acceleration with normalized SPT values for different intensity levels were drawn.Finally, by using standard attenuation curves, the above data were translated into epicentral distances, and good agreement with the known epicentral area was found. As a result, a consistent approach for liquefaction hazard and source location problems has been developed. The proposed method combines in its formulation historical evidence and earthquake engineering techniques.     

The catastrophic 1883 earthquake at the island of Ischia (southern Italy): macroseismic data and the role of geological conditions

This article presents the results of a detailed study of the effects of the 1883 earthquake, which occurred at the island of Ischia (Gulf of Naples) and produced the total destruction of buildings in the epicentral area (Casamicciola town). Despite the moderate magnitude, this event was characterised by very high intensities (I _max = XI degree MCS) mainly due to the shallow depth of the source. The study of the earthquake shows that the intensities, which decreased rapidly with distance, were affected by source directivity, according to the causative fault geometry and tectonic structures, while local amplification of damage was observed where soft soils outcrop. The attenuation of seismic intensity with distance was evaluated using the well-known relation of intensity versus epicentral distance (Blake’s method). The diverse gradients of attenuation, observed in different directions, were ascribed to the various geological features of the shallow crust of the island. In order to evaluate the role of geology in the damage level, we computed different attenuation models for stiff and soft soils outcropping on the island. A systematic local amplification of about 1 MCS degree associated to the presence of reworked tuffs was obtained. This study also shows the influence of geological conditions on the evaluation of macroseismic data and supplies useful elements to derive a predictive map of potential site effects.     

Isoseismal map of the Vrancea earthquake of March 4, 1977

The iaoseismal map of the intermediate Vrancea earthquake of March 4, 1977 was compiled using the contributions from many European countries within the shaken area. Characteristic features of the macroseiamic field are discussed. Mean radii of isoseismals and intensity attenuation are determined.     

Great earthquakes,seismicity gaps and potential for earthquake disaster along the Himalaya plate boundary

Analysis of the space-time patterns of seismicity in the Himalaya plate boundary has established the existence of three seismic gaps:

• 1.(1) The “Kashmir gap” lying west of the 1905 Kangra earthquake;
• 2.(2) the “Central gap”, situated between the 1905 Kangra and the 1934 Bihar earthquakes;
• 3.(3) the “Assam gap” between the 1897 and 1950 Assam earthquakes.

This study has shown that the above great earthquakes were preceded as well as followed by long periods (⩾ 19 years) of decreased levels of seismic activity in the epicentral regions. Remarkable decrease in the seismicity following the year 1970 has been observed in the western half of the Central gap as well as in the Assam gap. Local seismic investigation in the Assam gap confirms this feature and the seismicity suggests the existence there of an asperity.The local seismic investigations in Garhwal Himalaya have shown that the small earthquakes are confined to the upper 6–8 km of the crust and may have strike-slip motions. These earthquakes occur in a region where teleseismically recorded events were few.     

Inversion of seismic intensity data for the determination of three-dimensional attenuation structures in the central gap region of Himalayas

The central gap region of Himalaya, which lies in the northern part of the Indian subcontinent, is exposed to great seismic hazard. A three-dimensional attenuation structure (Q) of this region is obtained using the intensity data of four earthquakes (M 4.3–7.0) in the central Himalayan gap region and the damped least square inversion scheme. The technique is based on that given by Hashida and Shimazaki (J Phys Earth 32:299–316, 1984). The obtained Q structure explains the spatial distribution of isoseismals of the stronger earthquakes, which occurred in the recent past. The study area covers the Tehri town, which is the locale of one of the biggest earth fill dams of height 260 m. The spatial distribution of Q suggests that the Tehri town area is surrounded by lower Q medium, and hence any large earthquake in Tehri will pose great seismic hazard.     

HTP21/c–C2/c phase transition and kinetics of Fe2+–Mg order–disorder of an Fe-poor pigeonite: implications for the cooling history of ureilites

A natural Ca-poor pigeonite (Wo₆En₇₆Fs₁₈) from the ureilite meteorite sample PCA82506-3, free of exsolved augite, was studied by in situ high-temperature single-crystal X-ray diffraction. The sample, monoclinic P2₁/c, was annealed up to 1,093°C to induce a phase transition from P2₁/c to C2/c symmetry. The variation with increasing temperature of the lattice parameters and of the intensity of the b-type reflections (h + k = 2n + 1, present only in the P2₁/c phase) showed a displacive phase transition P2₁/c to C2/c at a transition temperature T _Tr = 944°C, first order in character. The Fe–Mg exchange kinetics was studied by ex situ single-crystal X-ray diffraction in a range of temperatures between the closure temperature of the Fe–Mg exchange reaction and the transition temperature. Isothermal disordering annealing experiments, using the IW buffer, were performed on three crystals at 790, 840 and 865°C. Linear regression of ln k _D versus 1/T yielded the following equation: ln k_\textD = - 3717( ±416)/T(K) + 1.290( ±0.378);    (R² = 0.988) \ln \,k_{\text{D}} = - 3717( \pm 416)/T(K) + 1.290( \pm 0.378);\quad (R^{2} = 0.988) . The closure temperature (T _c) calculated using this equation was ∼740(±30)°C. Analysis of the kinetic data carried out taking into account the e.s.d.'s of the atomic fractions used to define the Fe–Mg degree of order, performed according to Mueller’s model, allowed us to retrieve the disordering rate constants C ₀ K _dis⁺ for all three temperatures yielding the following Arrhenius relation: ln( C₀ K_\textdis ⁺ ) = ln K₀ - Q/(RT) = 20.99( ±3.74) - 26406( ±4165)/T(K);    (R² = 0.988) \ln \left( {C_{0} K_{\text{dis}}^{ + } } \right) = \ln \,K_{0} - Q/(RT) = 20.99( \pm 3.74) - 26406( \pm 4165)/T(K);\quad (R^{2} = 0.988) . An activation energy of 52.5(±4) kcal/mol for the Fe–Mg exchange process was obtained. The above relation was used to calculate the following Arrhenius relation modified as a function of X _Fe (in the range of X _Fe = 0.20–0.50): ln( C₀ K_\textdis ⁺ ) = (21.185 - 1.47X_\textFe ) - \frac(27267 - 4170X_\textFe )T(K) \ln \left( {C_{0} K_{\text{dis}}^{ + } } \right) = (21.185 - 1.47X_{\text{Fe}} ) - {\frac{{(27267 - 4170X_{\text{Fe}} )}}{T(K)}} . The cooling time constant, η = 6 × 10⁻¹ K⁻¹ year⁻¹ calculated on the PCA82506-3 sample, provided a cooling rate of the order of 1°C/min consistent with the extremely fast late cooling history of the ureilite parent body after impact excavation.     

Atlas of macroseismic maps for French earthquakes with their principal characteristics

The SIRENE macroseismic database has been utilized to draw isoseismal maps for the 140 best-documented French earthquakes, characterized by epicentral intensities of at least V (MSK) and located in all parts of the country. A study of focal depths derived from available local intensity data using an intensity versus distance decay law (Sponheuer) shows that the focal depths of most of the events considered do not exceed about 10 km. Their distribution correlates fairly well with regional dynamic geology features. A relationship is then computed between magnitude, intensity and focal distance, based on 73 instrumenta]ly recorded earthquakes (M _L between 3.3 and 6.3) and on 217 mean radius values (from 2 to 380 km) for isoseismals of intensity VIII to III (MSK). This relationship is applied to historical earthquakes contained in the database SIRENE which are characterised by their intensity only. These results are used in the evaluation as well deterministic as probabilistic of the seismic hazard on the national territory.     

On macroseismic attenuation parameters in the comparison of theoretical seismic hazard maps for Southern Calabria and Eastern Sicily (Southern Italy)

For two different zonations of the Calabro-Sicilian region the macroseismic intensity attenuation parameters are computed using the Grandori model.Some modifications to this relation are proposed here in order to allow its applicability also to those cases in which the data set available for each source zone does not present three successive epicentral intensity levels (I ₀) as required for its application.Maps of theoretical distribution of maximum expected intensities were plotted for both zonations adopted, in order to test the reliability, also using other attenuation models.The results of the analysis show how the proposed modifications to the Grandori relation allow the macroseismic intensity attenuation modelling even in cases in which only one intensity level is available.Finally, the comparison of theoretical maximum expected intensity distribution maps, computed for different attenuation models and seismogenic zonations, shows that the maps plotted using the Grandori model and the zonation adopted by G.N.D.T. (Gruppo Nazionale Difesa dai Terremoti - C.N.R. Italy) are more reliable.     

Estimation of seismic hazard with allowance for noncircular isoseismals of arbitrary orientation

A new mathematical model describing the field of macroseismic intensity has been elaborated. It is based on elliptic isoseismals. The orientation of the main axes of elliptic isoseismals depends on the direction of stretching of the main geological structures on the investigated territory.The new model of a macroseismic field was applied to the territory of Eastern Uzbekistan. Some results of macroseismic investigations of the effect of large regional earthquakes were used as initial data.A noncircular model of a macroseismic field was introduced into the integral of the seismic shakability of Riznichenko and, according to the model, a macroseismic shakability map for the territory of Eastern Uzbekistan was computed in isolines of the long-term mean return period of vibrations for the intensity I 8.Paper presented at the 21st General Assembly of the European Seismological Commission, Sofia, 1988.     

Experimental investigation of zoisite–clinozoisite phase equilibria in the system CaO–Fe2O3–Al2O3–SiO2–H2O

The system Ca₂Al₃Si₃O₁₁(O/OH)-Ca₂Al₂FeSi₃O₁₁(O/OH), with emphasis on the Al-rich portion, was investigated by synthesis experiments at 0.5 and 2.0 GPa, 500-800 °C, using the technique of producing overgrowths on natural seed crystals. Electron microprobe analyses of overgrowths up to >100 µm wide have located the phase transition from clinozoisite to zoisite as a function of P-T-X_ps and a miscibility gap in the clinozoisite solid solution. The experiments confirm a narrow, steep zoisite-clinozoisite two-phase loop in T-X_ps section. Maximum and minimum iron contents in coexisting zoisite and clinozoisite are given by X_ps^zo (max) = 1.9*10 ^{- 4} T+ 3.1*10 ^{- 2} P - 5.36*10 ^{- 2}{\rm X}_{{\rm ps}}^{{\rm zo}} {\rm (max) = 1}{\rm .9*10}^{ - 4} T{\rm + 3}{\rm .1*10}^{ - 2} P - {\rm 5}{\rm .36*10}^{ - 2} and X_ps^czo (min) = (4.6 * 10 ^{- 4} - 4 * 10 ^{- 5} P)T + 3.82 * 10 ^{- 2} P - 8.76 * 10 ^{- 2}{\rm X}_{{\rm ps}}^{{\rm czo}} {\rm (min)} = {\rm (4}{\rm .6} * {\rm 10}^{ - {\rm 4}} - 4 * {\rm 10}^{ - {\rm 5}} P{\rm )}T + {\rm 3}{\rm .82} * {\rm 10}^{ - {\rm 2}} P - {\rm 8}{\rm .76} * {\rm 10}^{ - {\rm 2}} (P in GPa, T in °C). The iron-free end member reaction clinozoisite = zoisite has equilibrium temperatures of 185ᇆ °C at 0.5 GPa and 0ᇆ °C at 2.0 GPa, with (H_r⁰=2.8ǃ.3 kJ/mol and (S_r⁰=4.5ǃ.4 J/mol2K. At 0.5 GPa, two clinozoisite modifications exist, which have compositions of clinozoisite I ~0.15 to 0.25 X_ps and clinozoisite II >0.55 X_ps. The upper thermal stability of clinozoisite I at 0.5 GPa lies slightly above 600 °C, whereas Fe-rich clinozoisite II is stable at 650 °C. The schematic phase relations between epidote minerals, grossular-andradite solid solutions and other phases in the system CaO-Al₂O₃-Fe₂O₃-SiO₂-H₂O are shown.     

The Ms = 7.0 Uureg Nuur earthquake of 15.05.1970 (Mongolian Altai): the aftershock process and current seismicity in the epicentral area

The aftershock process induced by the Ms = 7.0 Uureg Nuur earthquake, one of the largest events in the Altai, has been studied comprehensively. As an additional experiment, a temporary local network of seismic stations was deployed in 2006 in the epicentral area of the earthquake to gain more insights into the current tectonic activity. The aftershocks of the Uureg Nuur event were restricted to small faults in the interior of fault blocks rather than those being localized along border faults. Seismic activity across the directions of large faults has apparently been generated by a fault (in the Tsagaan Shuvuut Range) reactivated during the Uureg Nuur earthquake. The aftershock process, at its final phase, involved an adjacent crust block.     

Site response of the Ganges basin inferred from re-evaluated macroseismic observations from the 1897 Shillong, 1905 Kangra,and 1934 Nepal earthquakes

We analyze previously published geodetic data and intensity values for the M _s = 8.1 Shillong (1897), M _s = 7.8 Kangra (1905), and M _s = 8.2 Nepal/Bihar (1934) earthquakes to investigate the rupture zones of these earthquakes as well as the amplification of ground motions throughout the Punjab, Ganges and Brahmaputra valleys. For each earthquake we subtract the observed MSK intensities from a synthetic intensity derived from an inferred planar rupture model of the earthquake, combined with an attenuation function derived from instrumentally recorded earthquakes. The resulting residuals are contoured to identify regions of anomalous intensity caused primarily by local site effects. Observations indicative of liquefaction are treated separately from other indications of shaking severity lest they inflate inferred residual shaking estimates. Despite this precaution we find that intensites are 1–3 units higher near the major rivers, as well as at the edges of the Ganges basin. We find evidence for a post-critical Moho reflection from the 1897 and 1905 earthquakes that raises intensities 1–2 units at distances of the order of 150 km from the rupture zone, and we find that the 1905 earthquake triggered a substantial subsequent earthquake at Dehra Dun, at a distance of approximately 150 km. Four or more M = 8 earthquakes are apparently overdue in the region based on seismic moment summation in the past 500 years. Results from the current study permit anticipated intensities in these future earthquakes to be refined to incorporate site effects derived from dense macroseismic data.     

Recent activity and seismotectonics of the Eastern Pyrenees

Results from a recent earthquake in the Eastern Pyrenees are presented and the seismotectonics of the region is analyzed from the presently available data. On 26 September 1984 an earthquake (M_L = 4.4) took place in the area of the historical destructive earthquake of 1428. Several portable stations installed in the epicentral area to record aftershocks permitted of defining a precise location at 42°19.2′N, 2°10.2′E and 5 km depth. A maximum felt intensity of V (MSK) is obtained from macroseismic data. The epicentral location lies within a block bounded by E-W-trending structures and the focal solution shows right-lateral shearing with a NW-SE pressure axis.The seismicity in the Eastern Pyrenees shows a complex pattern which can be associated with both E-W fractures and NE-SW fault systems. Focal solutions of another two recent earthquakes of M_L ~ 4, with differences in horizontal pressure axis, are also discussed.     

Magnitude-Intensity Relationships in the Ibero-Magrebhian Region

In this paper we present magnitude (Ms) – magnitude(mb) and magnitude-intensity relationships which areconsidered the most adequate in the Ibero-Maghrebianregion. This work is based on selected samples ofrecently revised events with magnitude mb assigned bythe Instituto Geográfico Nacional (I.G.N.) and Msassigned by I.S.C and N.E.I.C., and isoseismal mapsfrom 142 events. Using these data, we have obtainedone magnitude (Ms) – magnitude (mb) relationship, twomagnitude (mb and Ms) assignment relationships viaepicentral intensity (I₀), and ten magnitude (mb andMs) assignments relationships via macroseismicinformation: four using Ambraseys' methodology (1985)and six using the isoseismal area of degree III, IV and VI.According to the obtained results it could be concluded that historical magnitude assignment with lesser uncertainties are those obtained via macroseismic information using magnitude-intensity relationships with Ambraseys' methodology (1985). The magnitude-isoseismal area assignment relationships have, in most cases, great differences depending on the degree of the isoseismal area used. Magnitude assignments via epicentral intensity have the highest uncertainties. Geographic regionalization of the relationshipshas been studied but the highest correlations and statistical significance are obtained when we fit all the Ibero-Maghrebian region data.Finally we have used the results obtained in this workto assign magnitude to some important historicalearthquakes in the Ibero-Maghrebian region: the 1755Lisbon earthquake, the 1680 Málaga earthquake, the1829 Torrevieja earthquake and the 1884 Arenas del Reyearthquake. According to our relationships andmethodology we have assigned an Ms value of 9.3 ±0.6 to the 1755 Lisbon earthquake (its mb magnitudecannot be estimated due to the saturation of the mbscale), an mb value of 6.3 ±0.4 and an Ms valueof 6.9 ± 0.6 to the 1829 Torrevieja earthquake, anmb value of 6.2 ± 0.4 and an Ms value of 6.4 ±0.6 to the 1680 Málaga earthquake and an mb valueof 6.1 ± 0.4 and an Ms value of 6.5 ± 0.6 tothe 1884 Arenas del Rey earthquake.     

Atténuation de l'intensité macrosismique pour la France métropolitaine : importance de l'intensité épicentrale

The main result of this work is to show that macroseismic intensity decay with distance strongly depends on the epicentral intensity. An attenuation law that takes this parameter into account is proposed for Metropolitan France, from the analysis of SISFRANCE macroseismic database. Such a model significantly reduces the difference between observed and theoretical intensities. A map of the attenuation variations is also set up for Metropolitan France. No major site effects are observed, but at a broad scale, young Alpine regions display a stronger attenuation than old Hercynian regions. To cite this article: P. Arroucau et al., C. R. Geoscience 338 (2006).     

Practical Estimates of Tensile Strength and Hoek–Brown Strength Parameter m i of Brittle Rocks

By applying the Griffith stress criterion of brittle failure, one can find that the uniaxial compressive strength (σ_c) of rocks is eight times the value of the uniaxial tensile strength (σ_t). The Griffith strength ratio is smaller than what is normally measured for rocks, even with the consideration of crack closure. The reason is that Griffith’s theories address only the initiation of failure. Under tensile conditions, the crack propagation is unstable so that the tensile crack propagation stress (σ_cd)_t and the peak tensile strength σ_t are almost identical to the tensile crack initiation stress (σ_ci)_t. On the other hand, the crack growth after crack initiation is stable under a predominantly compressive condition. Additional loading is required in compression to bring the stress from the crack initiation stress σ_ci to the peak strength σ_c. It is proposed to estimate the tensile strength of strong brittle rocks from the strength ratio of R = \fracs_\textc | s_\textt | = 8\fracs_\textc s_\textci . R = {\frac{{\sigma_{\text{c}} }}{{\left| {\sigma_{\text{t}} } \right|}}} = 8{\frac{{\sigma_{\text{c}} }}{{\sigma_{\text{ci}} }}}. The term \fracs_\textc s_\textci {\frac{{\sigma_{\text{c}} }}{{\sigma_{\text{ci}} }}} accounts for the difference of crack growth or propagation in tension and compression in uniaxial compression tests. \fracs_c s_ci {\frac{{\sigma_{c} }}{{\sigma_{ci} }}} depends on rock heterogeneity and is larger for coarse grained rocks than for fine grained rocks. σ_ci can be obtained from volumetric strain measurement or acoustic emission (AE) monitoring. With the strength ratio R determined, the tensile strength can be indirectly obtained from | s_\textt | = \fracs_\textc R = \fracs_\textci 8. \left| {\sigma_{\text{t}} } \right| = {\frac{{\sigma_{\text{c}} }}{R}} = {\frac{{\sigma_{\text{ci}} }}{8}}. It is found that the predicted tensile strengths using this method are in good agreement with test data. Finally, a practical estimate of the Hoek–Brown strength parameter m _i is presented and a bi-segmental or multi-segmental representation of the Hoek–Brown strength envelope is suggested for some brittle rocks. In this fashion, the rock strength parameters like σ_t and m _i, which require specialty tests such as direct tensile (or Brazilian) and triaxial compression tests for their determination, can be reasonably estimated from uniaxial compression tests.     

The 20 March 1992 South Aegean,Greece, earthquake (Ms= 5.3): possible anomalous effects

The earthquake (M_s= 5.3) of 20 March 1992 and its aftershocks, which occurred near the volcanic island complex of Milos, South Aegean, Greece, are studied on the basis of filed observations and instrumental data. The mainshock caused some building damage, the maximum intensity of VI+ (MM) being assigned to Triovasalos, Milos. Ground cracks, liquefaction in soil, landslides and rockfalls were observed in Milos. Liquefaction took place at an apparently anomalously long epicentral distance (D= 12 km) and is associated with unusually small earthquake magnitude. Abnormal animal behaviour was reported no longer than twelve hours before the mainshock. The b-value (= 1.02) of the G–R relation for the aftershock sequence, the exponentially decreasing number of aftershocks with time, and the difference (= 0.5) in magnitude between the mainshock and its largest aftershock imply that the origin of these earthquakes is tectonic and not associated with the volcanic field of Milos.     

Minimum norm inversion of observed ground elevation changes for slips on the causative fault during the 1905 Kangra earthquake

We estimate the distribution of slip in the dip section of the causative fault for the 1905 Kangra earthquake by applying the minimum norm inversion technique to differences in pre- and post-earthquake levelling data collected along the Saharanpur-Dehradun-Mussoorie highway. For this purpose it is assumed that the causative fault of the 1905 Kangra earthquake was planar with a dip of 5° in the northeast direction and that it had a depth of 6 km at the southern limit of the Outer Himalaya in Dehradun region. The reliably estimated maximum slip on the fault is 7.5 m under the local northern limit of the Outer Himalaya. Using the inverted slip distribution we estimate that the maximum permanent horizontal and vertical displacements at the surface due to the Kangra earthquake were about 4 m and 1.5m respectively. The maximum transient displacements at the surface should have exceeded these permanent displacements. These estimates of maximum slip on the causative fault and the resultant maximum permanent and transient displacements at the surface during the Kangra earthquake may be taken tentatively as being representative of the great Himalayan earthquakes.