Recent Crustal Movements Research Articles

Stability problems in road and pipeline constructions and their mitigation — Examples from Sakhalin and Azerbaijan

The paper gives two examples of larger construction projects with typical stability problems. The first example is from Sakhalin Island in the Russian Far East. It is connected with a construction of oil and gas pipelines through the mountainous terrain in Makarov region. The region has an active geotectonic history and is highly affected by uncontrolled erosion and extensive landslips. Basic principles of landslide hazard mitigation are presented. The second example is from a motorway construction in Azerbaijan. This motorway leads from Baku to Russia through a seismo-tectonically active area at the toe of Caucasian mountains and in some places is situated in deep cuts at the toe of high slopes. This unsuitable routing, together with seismic activity, led to a slope stability failure of a slope affected by recent tectonic movements near the village of Devechi. Stability conditions and designed remedy measures are presented.

Quartz tube extensometer for observation of Earth tides and local tectonic deformations at the Sopronbánfalva Geodynamic Observatory, Hungary

In May 1990, a quartz tube extensometer was installed in the Sopronbánfalva Geodynamic Observatory of the Geodetic and Geophysical Research Institute (GGRI) of the Hungarian Academy of Sciences for recording Earth tides and recent tectonic movements. The paper describes the construction of the extensometer and a portable calibrator used for the in situ calibration of the instrument. The extensometer is very sensitive. Its scale factor is 2.093+/-0.032 nm/mV according to the highly precise calibration method developed at the GGRI. Since the stability of extensometers is strongly influenced by the geological structure and properties of the rocks in the vicinity of the recording site, the observatory instrument system was tested by coherence analysis between theoretical (as the input signal) and measured tidal data series (as the output signal). In the semidiurnal tidal frequency band the coherence is better than 0.95, while in the diurnal band it is about 0.8. Probably this is due to the fact that the noise is higher in the diurnal band (0.4-0.5 nstr) than in the semidiurnal band (0.19-0.22 nstr). Coherence analysis between theoretical and measured data corrected for barometric changes yielded a small improvement of coherence in both frequency bands, while using temperature data correction, no observable improvement was obtained. Results of the tidal analysis also show that the observatory instrument system is suitable for recording very small tectonic movements. The 18 years of continuous data series measured by the extensometer prove the high quality of the extensometer. On the basis of investigations, it was pointed out that further efforts should be done to improve the barometric correction method and that correction for ocean load, as well as considering topographic and cavity effects are necessary to increase the accuracy of determining tidal parameters.

Recent vertical crustal movements and resulting surface deformation within the North German Basin (Schleswig-Holstein) derived by GIS-based analysis of repeated precise leveling data

Recent vertical crustal movements and resulting surface deformation within the North German Basin (Schleswig-Holstein) derived by GIS-based analysis of repeated precise leveling data

Stratigraphic units of the Apulian Tavoliere plain (Southern Italy): Chronology, correlation with marine isotope stages and implications regarding vertical movements

The geologic study of the Apulian Tavoliere plain (Apulia region, southern Italy) is extremely difficult due to the scarcity of outcrops and fauna that could be used for dating. The survey in progress of the 1:50,000 scale geological sheet no. 409 “Zapponeta” (including the coastal zone of the Apulian Tavoliere) has prompted us to tackle this problem by using a large set of borehole data and the AAR dating method applied to ostracod shells, which are capable of colonizing all types of environment as long as there is water. This alternative approach has allowed us to recognise nine stratigraphic units or synthems and, for the first time in this area, to date them, and to find a correlation between them and the cycles of sea level variation. The recognised stratigraphic units are: the Coppa Nevigata sands (NEA; middle Pleistocene: MIS 17–16), a rgille subappennine unit (ASP; middle Pleistocene: MIS 15–13), the Coppa Nevigata synthem (NVI; middle Pleistocene: MIS 11), the Amendola subsynthem (MLM 1; middle Pleistocene: MIS 11), an undifferentiated continental unit (UCI; middle Pleistocene: MIS 8–7), the Foggia synthem (TGF; middle–late Pleistocene: MIS 6), the Carapelle and Cervaro streams synthem (RPL; late Pleistocene: MIS 5–3), and the Inacquata farm synthem (NAQ; Holocene). Within the RPL unit, a buried Cladocora caespitosa bioherm referable to MIS 5.5, lacking in warm fauna, and in which the coral is embedded in clay has been found in some boreholes. This is the first finding of Tyrrhenian deposits with C. caespitosa along the Italian Adriatic coast; the presence of this coral in clayey sediments, a very uncommon occurrence, strengthens the hypothesis that the major fossil reefs grew in coastal waters that were characterised by alluvial inputs of fine sediments, higher turbidity, and higher temperature than today. In addition, on the basis of the current evidence, some consideration about the fauna of the MIS 5.5 layer allows us to hypothesise that the Adriatic Sea underwent a more moderate warming compared to that of the Ionian and Tyrrhenian seas. Instead, the finding in the NVI unit of a tropical lagoonal deposit with stromatolites referred to MIS 11 proves that the warming in this stage was undoubtedly greater than that of MIS 5.5. The MM4 borehole, which goes through the MIS 5 layers of the RPL unit, made it possible to recognise two marine phases during MIS 5: the first is referable to the MIS 5.5–5.3 interval, and the second to MIS 5.1. MIS 5.2 is marked by land emersion, whereas no evidence of land emersion between MIS 5.5 and 5.3 has been found. Also for the first time in this area, uplifting and subsiding areas have been recognised and the vertical movements assessed. In general, the data suggest that the Garganic Apulian foreland and the Amendola highland experienced an uplift, while the central-southern part of the study area, belonging to the Apulian Tavoliere plain, suffered a subsidence with rates increasing from north–northwest to south–southeast. In particular, the finding of the MIS 5.5 buried layer with C. caespitosa has allowed us to fill a gap in the data regarding the recent tectonic movements along the Adriatic coast ( Ferranti et al., 2006). This feature proves that there has been a recent subsidence event since MIS 5.5 in the coastal area of the Apulian Tavoliere plain.

Tectonophysical research at Institute of the Earth's crust SB RAS: major achievements and actual problems

The article presents major results which have been obtained during 30 years of researches conducted by the Laboratory of Tectonophysics at the Institute of the Earth’s Crust. General regularities in organization of fault-block structures in the brittle lithosphere are established. Relations between main parameters of faults are investigated, and their connection with the lithospheric structure and recent crustal movements is shown. A rheological model of vertical zoning of faults is proposed. Internal structures of faults are studied; stages in faulting are generally defined in terms of time; regularities of patterns of joints inside faults are described; and original methods of mapping such joints are proposed to reveal tectonic conditions of faulting. Based on seismic monitoring, new methods of quantitative assessment of relative activity rates of faults in real time are developed. Such methods are applied to delineate zones of recent destruction of the lithosphere in the Central Asian region. The state of stresses of the lithosphere is mapped, and the new map allows us to reveal regularities in the spatial mosaic of regions differing by types of stress fields. Our physical experiments conducted in compliance with similarity conditions are aimed at studying faulting mechanisms with regard to variable loads. A special set of experiments is devoted to the Baikal rift system. Cases of application of tectonophysical methods to study fault tectonics, the state of stresses and seismicity of the lithosphere are described. Prospects of tectonophysical researches conducted in the Laboratory and potentials of integration with studies of other research teams are considered.

Recent and Late Holocene vertical crustal movements in the Southeast Baltic—The transition zone between the Fennoscandian shield and the Russian plate

The paper analyzed recent vertical crustal movements and compared them with Late Holocene ones (over several thousands of years) with the case study of the transition zone between the Fennoscandia shield and the Russian plate. The study of recent and young movements is based on long-term sea level and repeated geodetic measurements and on geologic geomorphic data, respectively. The data set makes it possible to establish that a weak uplift of the territory gives way with regularity to a weak subsidence after going across the zone of zero movements that agrees with the modern geodynamic constructions and can serve as the basis of long-term prognostic estimations. The results are compared with the newest GPS measurements and with the theoretical model of viscoelastic deformations in the periphery of the past glaciation area during its postglacial isostatic adjustment

GPS monitoring of recent crustal movements in Kamchatka and the Commander Islands during 1997–2007

This is a review of the geodetic monitoring of the horizontal component of recent crustal movements (RCMs) in Kamchatka and the Commander Islands for the period 1979–2007. Examples are provided of the RCMs recorded in Kamchatka and the Commander Islands for the period 1997–2007 by the Kamchatka regional GPS network (KAMNET) set up by workers at the Kamchatka Branch of the RAS Geophysical Service (KB GS RAS) in collaboration with the Institute of Volcanology and Seismology of the Far East Division of the Russian Academy of Sciences to study the geodynamic processes that are occurring in the Kamchatka subduction zone. An interpretation of examples of recorded RCMs is given.

Geomorphic imprints of neotectonic activity along the frontal part of eastern Himalaya, Pasighat, east Siang district, Arunachal Pradesh

Geomorphology in relation with tectonics has been studied along the Himalayan frontal part around Pasighat, Eastern Himalaya Arunachal Pradesh Squeezed between Main Boundary Thrust and Himalayan Frontal Thrust (HFT), the morphology of the area indicates significant influence by tectonic processes. The streams including the Siang River show anomalous drainage patterns whenever they cross the lineaments. Mountain front sinuosity index, and development of deeply incised narrow valleys along the front zone indicate recent tectonic movement along the HFT. Four levels of terraces are observed In the Pasighat area. Terraces show crude stratification of their constituents. Three levels of unpaired terraces are observed in Roing-Balek area. Paleochannel reconstruction suggests a gradual eastward migration of the Siang River, which shows a swing in its flow direction from N-S to present NW-SE. Drainage basin asymmetry vectors, calculated from transverse topographic profiles of two segments, suggest preferred stream migration towards northeast and southeast direction in response to northeastward and southwestward ground tilting.

Field of tectonic stresses from focal mechanisms of earthquakes and recent crustal movements from GPS measurements in China

Orientations of the principal axes of the tectonic stress field reconstructed from seismological data on focal mechanisms of earthquakes and strain fields determined from GPS measurements in China are compared. The data of GPS measurements used in the paper were obtained by the Crustal Movement Observation Network of China (about 1000 stations) in the period of 1998–2004. On the basis of information on the recent horizontal crustal motions, the strain field is calculated for the study territory by the finite element method. Calculations of the strain tensor using GPS data were carried out with a step of 1° in latitude and longitude. A catalog of earthquake focal mechanisms was used for the reconstruction of tectonic stress field components. Focal mechanisms of earthquakes were calculated with the use of seismological data on signs of first arrivals from the bulletin of the International Seismological Center. To estimate characteristics of the regional stress field, an approach based on the kinematic method proposed by O.I. Gushchenko was applied. The tectonic stress field was reconstructed in depth intervals of 0 < H < 35 km and 35 km < H < 70 km from data on focal mechanisms of earthquakes over the periods of 1998–2004 and 1985–2004. Comparison of directions of the principal strain axes at the surface (according to GPS measurements) and directions of the principal stress axes (reconstructed from focal mechanisms of earthquakes) showed their good convergence. Seismotectonic strains and GPS measurements coincide within a larger part of the territory. The coincidence is best in a depth interval of 0 < H < 35 km. Maximum misfit values are confined to areas of high 3-D gradients of strain axis directions and are possibly related to the structural heterogeneity of the region, zones with strains of the same type along both horizontal axes (compression or extension along all directions), or areas of small absolute values of recent horizontal movements. Areas with invariable directions of the stress axes are recognizable regardless of the depth of initial data. Good reproducibility of results obtained by two different methods made it possible to check the method of stress field reconstruction using data on focal mechanisms of earthquakes.

Investigation of the relationship between subsurface structures and mass movements of the high loess bank along the River Danube in Hungary

Abstract Relationships between regional tectonics, subsurface structures and mass movements are investigated on the high loess bank of the River Danube at Dunafoldvar based on remote sensing data, gravity and tilt measurements. The geology and morpho-tectonics of the area were derived from remote sensing images. The basement structure under the high loess bank and in its surroundings was revealed by gravimetric measurements. On the basis of these data a model for the surface mass movements was developed and compared to the results of the surface tilt measurements. Two explanations for the measured tilt have been considered, a tectonic one and a geomorphologic one. The data in the former are treated as being the consequence of recent tectonic movements. According to this approach the SSW tilt on the top of the high bank originates from the very slow movements of Felső-Oreg-hegy towards the southwest as a result of an ENE–WSW compression. In the geomorphologic explanation the movements are the consequence of erosion and undercutting of the riverbank caused by the Danube, which has led to the slow loss of the base support of the high bank, resulting in slow sliding eastwards accompanied by counterclockwise rotation of the Felső-Oreg-hegy block. In accordance with these explanations, most probably the measured tilt rate is the consequence of both tectonic and geomorphologic processes. In order to prove active tectonism on the territory long-term tilt and geodetic deformation measurements are necessary on a wider area than the recent test site.

Recent vertical crustal movements of a part of the Balkan Peninsula derived from levelling data

The historical levelling data of the epoch of 1950-1960 were used along with the levelling data of the epoch of 1970-1973 for the derivation of the vertical velocity field on the territory of the Republic of Serbia. The methodology was based on the construction of a kinematic network and least squares adjustment and aimed at obtaining the vertical velocities of representative benchmarks. Being the first attempt of this kind for the area under investigation, no further interpretation of the result is given, apart from a couple of remarks concerning the correlation between the gradient surface and the general geophysical features.

Tidal notches in Vinodol Channel and Bakar Bay, NE Adriatic Sea: Indicators of recent tectonics

Detailed mapping of coastline in Vinodol Channel and adjacent bays in the Kvarner area (Northern Adriatic Sea) revealed the existence of well expressed submerged notches ranging in their elevation from 45 to 115 cm below mean sea level. Noticeable difference in the height of these presumably coeval tidal notches is attributed to neotectonic movements since the Roman times. The difference of ∼ 0.1 m on opposite parts of Vinodol Channel is in accordance with the presumed thrusting tectonics in the adjacent Vinodol Valley. The deeper position of coeval tidal notches in Bakar Bay (the drowned part of Vinodol Valley) indicates it is the tectonically most active zone. Investigation of tidal notches in this case complements information from the solid rock geology and measurements of recent tectonic movements revealed by GPS positioning. Moreover, it indicates the potential of detailed mapping of tidal notches for neotectonic research in some coastal areas.

Geological Environment and Disasters along railway line in the Qinghai-Tibet Plateau

Taking ETM as the main remote sensing information and adopting the Digital Landslide Technique, geological environments and large scale disasters along the Qinghai-Tibet highway and railway line regions have been investigated. The region can be divided into six basic tectonic units, and each of them has a different Quaternary deposition and other rocks, and different tectonic characteristics, but all of them extend with EW and NWW tectonic and dense faults, and also with high intensity of recent tectonic movement mainly taking the uplifting style. Based on the different undulated characteristics, the regional landform can be divided into three sections, the north-up steep slope, middle-gentle plateau plane, and south-down slope. Large scale periglacial geographical phenomena, such as rock glacial, landslide, debris flow, block field, rock-flow, and moving sand dune, which have been correlated with high elevation and frozen soil environment, are the main geological disasters that may impact the Qinghai-Tibet highway and railway lines.

Observation of recent tectonic movements by extensometers in the Pannonian Basin

In Hungary four extensometric observatories were established in the last two decades. The extensometers were installed primarily for observations of Earth tides. A 15-year continuous data series (1991–2005) was recorded at the Sopronbánfalva station and a 7-year record (1993–1999) was obtained at the Pécs station. The length of the measured continuous data series at the two other stations (Bakonya and Budapest) is only a few years. The long-term data records were also applied to the investigation of long-periodic deformations caused by recent tectonic movements. To get an insight into the present day tectonic processes on the margin of the Pannonian Basin, the measurement results of two additional stations (Vyhne in Slovakia and Beregovo in Ukraine) were also included into the investigations. The seasonal variations in the long data series due to temperature and air pressure effects were eliminated. The residual curve – after the correction of the seasonal effects and filtering the “high frequency” components (e.g. earthquakes, Earth tides, etc.) – contains the instrumental drift. It is impossible to determine this curve mathematically. It can be diminished by special instrumental solutions and by regular calibration of the instruments. This paper shows methods and possible solutions how the instrumental drift was investigated and eliminated in order to get the most reliable data for studying recent tectonic movements. The reliability of the extensometric measurements was tested by the tidal evaluation of the data series. The results of the observations show that the Pannonian Basin is under compressive stress. The strain rates measured by extensometers on the margin of the basin are about three orders of magnitude higher than the intra-plate strains obtained by GPS measurements. The reason for this large difference arises from the interaction between the plate boundary and intra-plate forces and from the different measurement techniques. Investigations showed that the rate of the tectonic movements varies, and depends on the local geographical and topographical conditions.

A modified least-squares collocation method for the determination of crustal deformation: first results in the Swiss Alps

SUMMARY The calculation of recent crustal movements and the associated crustal deformation rely on a suitable interpolation of geodetic measurements with repetition cycles of years or decades and modern GPS permanent networks. A common interpolation methods is the least-square collocation (LSC). LSC requires some a priori assumptions about the characteristics of the velocity field, that is, stocasticity in Moritz's definition of LSC. We present a novel approach, called adaptative LSC (ALSC) to the interpolation of non-stochastic fields, which encompass the traditional LSC and the block model as special cases. This modified collocation method is based on the empirical estimation of a anisotropic and inhomogeneous covariance function of the interpolated field. The method has been tested on synthetic data that simulate geodetic measurements over a triple plate junction and with real data from precise levelling measurements over the Swiss Alps. In both cases, ALSC gave better and more stable results, compared to LSC and other interpolation methods, such as smoothed splines.

Crustal Movement Observed by GPS and Earthquake Activity in the Chinese Mainland and its Neighborhood

The general characteristics of the recent horizontal crustal movement in the Chinese Mainland and the horizontal crustal movements before the Kunlun Mountain earthquake of M8.1 on Nov. 14, 2001 and two earthquakes of M 8.0 and M 7.9 occurred in Sept. 2003 around the Chinese Mainland are analyzed with GPS data obtained in the Crustal Movement Observation Network of China (CMONOC). Relative vertical displacements observed in the last five years at fiducial stations show that there was a significant correlation between the length of day and the vertical displacements at most stations in western China.

Compilation of a Map of Recent Vertical Crustal Movements in Eastern Canada Using Geographic Information System

In this paper, we use geographic information system as a useful tool in compiling vertical crustal movement (VCM) over Eastern Canada. For modeling linear VCM, we employ tide gauge records and precise releveled segments, which reflect the glacial isostatic submergence of the coasts, as well as other global, regional, and local effects. The area of study is divided into two zones: Maritimes and South St. Lawrence zones. Piecewise polynomial surfaces of different orders are calculated by the method of least squares for each region to obtain representations of the recent vertical movements. This work provides the framework for multidisciplinary studies of geodynamics in the region, allowing different selection of zones for vertical crustal movements and simplifying the incorporation of more data in future investigations. We use ArcGIS to visualize the theoretical approaches, and to integrate and analyze different spatially distributed data. This powerful tool helps us to produce a more physically meaningful VCM map for the region. The map reflects the most significant geophysical phenomenon in the region, postglacial rebound, and it is in good agreement with the 2004 glacial isostatic adjustment model of Peltier [ICE-5G(VM2)].

Investigation of earthquakes' geo-surroundings in the Pannonian Basin by using GIS tools

The mechanism of earthquake occurrence in the Pannonian Basin is not clear in most cases (in other words, it is often not possible to find a relationship between the location of epicenters and the elements of the maps of recent tectonic movements), hence a GIS has been created in order to clarify the origin of these events. The special seismological GIS includes all relevant information (maps and joint database) concerned with earthquakes covering the whole territory of Hungary. GIS contains the following maps: special macro- and microseismic epicenters and their parameters; different active tectonic fault maps; digital terrain model of the recent relief; digital terrain models of different geological basements; appropriate geophysical anomaly maps; Quaternary sediment thickness; recent rivers, water streams and settlements. GIS enables us to carry out special operations between different layers by applying its tools in order to reveal the recent tectonic movements and to throw light upon the generation of possible earthquake occurrences. Results of the present investigation in GIS revealed that significant relation exists between the earthquake foci and recent tectonic lines. Some foci, however, can not be related to fracture lines. One part of earthquakes showed agreement with Pre-Tertiary basement areas of considerable slope, with the recent tectonic elements of Geomorphological maps and with the piedmonts of the North Hungarian Range. Some traces of recent movements have been found with the help of the multiplication map of Quaternary sediment thickness map and Recent relief (Digital Elevation Model).

GPS measurements of horizontal deformation across the Lai Chau—Dien Bien (Dien Bien Phu) fault, in Northwest of Vietnam, 2002-2004

Abstract Global Positioning System (GPS) measurements from Feb. 2002 through Mar. 2004 were used to estimate the recent crustal movement along the Lai Chau—Dien Bien (Dien Bien Phu) fault (LC-DBF) system in the Northwest of Vietnam. Four GPS campaign data were processed to estimate ITRF2000 and local horizontal velocities, as well as extensive and compressive strain rates across the LC-DBF. ITRF2000 velocities are consistent with east-southeastward movement of Sundaland i.e. Indochina. Local velocities did not reveal much left-lateral strike-slip of the fault system and the derived strain rates were insignificantly different from zero at 95% confidence.

Geodynamic processes in seismically active areas of the Tien Shan from monitoring data with the use of nuclear explosions

Recent geodynamic processes in the Tien Shan region are studied by the analysis of time series of effective velocities and traveltime delays relative to the IASPEI-91 traveltime curve of the weakly refracted wave P n from nuclear explosions at the Semipalatinsk test site over the period of 1968–1989. The time series were constructed for 10 seismic stations located at distances of 800–1200 km from the test site in the regions of the Northern, Central, and Southern Tien Shan. The twenty-year period of observations at stations in the North Tien Shan showed a significant decrease in traveltime delays by 0.20–0.76 s, which corresponds to a 0.2–0.7% increase in seismic velocities. An opposite pattern is observed at stations of the Central and Southern Tien Shan: traveltime delays increased by 0.2–0.5 s and, accordingly, seismic velocities dropped by 0.2–0.5%. These results suggest the predominance of compression processes in the crust and upper mantle during the period of observations in Northern Tien Shan and extension processes in the Central and Southern Tien Shan. The series of velocities and traveltime residuals are characterized by the presence of rhythmic oscillations of various amplitudes and periods against a linear trend. A correlation between variations in kinematic parameters and yearly numbers of earthquakes is observed at all stations. Diagrams of the spectral time analysis reveal rhythms with periods of 2–3 and 5–7 yr. The data obtained in this study are consistent with results of studying the stress-strain state of the Tien Shan crust from focal mechanisms of earthquakes and the velocities of recent crustal movements from GPS data. It is found that the amplitude of variations in kinematic parameters of the P wave at stations located in seismically active regions (the Tien Shan, Kopet Dagh, the Caucasus, Altai, and Sayany) is two to five times higher compared to aseismic regions (the Russian and Kazakh plains).