Deformation of the Earth’s crust in the Northern Tien Shan according to the earthquake focal data and satellite geodesy

Kostyuk, A. D.; Сычева, Н. А.; Yunga, S.; Богомолов, Л. М.; Yagi, Y.

doi:10.1134/s1069351310030055

Cited by 12 publications

(5 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For detailed analysis and interpretation of the average linear velocities of horizontal movements in the Penola Strait -Lemaire Channel fault area, the dilatation parameters (area change) are used which characterize the relative expansion (increase in area) or compression (area decrease) of the territory, as well as the total shear characterizing the horizontal heterogeneity of the deformed territory. Based on the analysis of previous studies conducted on the Antarctic Peninsula (Tretyak and Golubinka, 2006), the northern Tian Shan (Kostiuk et al, 2010), the south-eastern Europe (Marchenko et al, 2012), Europe (Tretyak and Vovk, 2014), the northern part of Egypt (Mohamed et al, 2016) it was found that dilatation and total shear parameters are optimal for a detailed analysis and interpretation of recent local geodynamic processes of the studied area.…”

Section: Geodynamic Interpretation Of the Resultsmentioning

confidence: 98%

Recent local geodynamic processes in the Penola Strait_Lemaire Channel fault area (West Antarctica)

Savchyn¹

2021

Acta Geodynamica Et Geomaterialia

View full text Add to dashboard Cite

We present the crustal deformation field in the Penola Strait – Lemaire Channel fault area (West Antarctica), based on the analysis of the 5 seasonal cycles of static GNSS survey. This 5 GNSS campaigns were conducted with approximately a 16-year interval from 2003 to 2019. The analyses indicate that average linear velocities of horizontal movements are multidirectional but no larger than 1 – 2 mm/yr. Average linear velocities of vertical movements are no larger than ±3 mm/yr. In the present work scheme of vertical and horizontal movements has been drawn out. The obtained results correlate well with the movements of the surrounding GNSS stations. Based on the analysis of spatial distribution of the Earth’s surface dilatation velocity the zones of extreme compression and expansion values were revealed. The analyses of spatial distribution of the Earth’s surface total shear velocity indicate that the studied region is horizontally heterogeneous. Based on the analysis of obtained results, a new kinematic model of fault area was developed. The possibility of using static GNSS survey to study recent local geodynamic processes in Antarctica has been demonstrated.

show abstract

Section: Geodynamic Interpretation Of the Resultsmentioning

confidence: 98%

Recent local geodynamic processes in the Penola Strait_Lemaire Channel fault area (West Antarctica)

Savchyn¹

2021

Acta Geodynamica Et Geomaterialia

View full text Add to dashboard Cite

show abstract

“…Ранее это уже было отме-чено в работе [Kostyuk et al, 2010]. Исключением служит Суусамырская впадина со всесторонним укорочением, наибольшим по северо-северо-вос-точному направлению осей по данным GPS, и ре-жимом, близким к горизонтальному сдвигу с севе-ро-западным направлением оси сжатия по данным СТД.…”

Section: сравнение результатов оценки деформационного режима на основunclassified

“…В основе метода лежит расчет параметров тензора приращений СТД и построение на их основе карт СТД, распределения коэффициента Лоде -Надаи, угловых параметров напряженно-де-формированного состояния и др. Результаты при-менения этого метода ранее были опубликованы в работах [Sycheva, 2005;Sycheva et al, 2005Sycheva et al, , 2008Kostyuk et al, 2010]. В работе в качестве исходных данных рассматривались фо-кальные механизмы очагов 870 землетрясений слабой и умеренной силы, произошедших в период с 1994 по 2004 г. Решения по механизмам очагов были получены по знакам вступления P-волн.…”

Section: Introductionunclassified

“…В работе в качестве исходных данных рассматривались фо-кальные механизмы очагов 870 землетрясений слабой и умеренной силы, произошедших в период с 1994 по 2004 г. Решения по механизмам очагов были получены по знакам вступления P-волн. В ра-боте [Kostyuk et al, 2010] СТД рассчитывались по механизмам очагов 76 землетрясений с K>9.75, произошедших за 1996-2006 гг. и определенных по методу инверсии.…”

Section: Introductionunclassified

See 1 more Smart Citation

Comparison of Crustal Deformation Rates Estimated From Seismic and GPS Data on the Bishkek Geodynamic Polygon

Сычева¹,

Мансуров²

2017

Geodin. tektonofiz.

Self Cite

View full text Add to dashboard Cite

Abstract:The Bishkek geodynamic polygon (BGP,.5° N -73-77° E) is located within the central segment of the North Tien Shan seismic zone, in the junction zone of the Tien Shan orogene and the Turan plate ( Fig. 1). In the entire modern structure of Tien Shan lengthwise zones of shearing (with both right-and left-lateral strike-slip faults) are observed, thus Tien Shan can be considered as a transpression zone. Our study aimed at comparing deformation values estimated for the BGP territory from the seismic and GPS data. The modern stress-strain state of the study area was determined from the focal mechanisms of 1287 earthquakes that occurred in the period from 1994 to 2015. The study area was divided into cells with a radius of 0.2° (~20 km). The cell centers were in the nodes of the grid with a spacing of 0.1° (~10 km). A tensor of a seismotectonic deformation (STD) rate within a cell was calculated as a sum of seismic moment tensors normalized for time, volume and shear modulus, assuming that STD is similar at different scale levels. The STD field is shown in Figure 4 at the background given by the deformation intensity pattern. Figure 6 shows the scatter of the sums of the strain rate tensor's horizontal components estimated from the seismic data. The modern crustal movements were estimated from the geodetic measurements performed on the Central Asian GPS Network. Using the crustal movement velocities for 90 sites in the study area, the deformation processes in the crust were modeled based on the linear part of the Taylor expansion of the point's-velocity-versus-its-radius-vector function. Then the velocity gradient tensors were estimated for the grid nodes with a spacing of 8.3 km. To estimate tensor's value in every single grid node a system of linear algebraic equations was solved by the weighted least-squares method. The weight of an observation point decreased with an increasing distance to such point, so that the inhomogeneity of the deformation field could be taken into account. From the velocity gradient tensors we calculate the strain rate tensors (Fig. 5) and then the rate of changes of the area (meterage) ∆ (Fig. 7). A comparison of Figures 4 and 5 shows a general coincidence between the directions of compression/shortening axes estimated from the seismic and GPS data. On average, the STD intensity is by two to three orders lower than the deformation intensity assessed from the GPS data. It can be explained by the fact that the horizontal components of the total deformation amounts visible in the GPS data are actually the sums of aseismic and coseismic components, and the deviator part of coseismic component was considered as STD. Comparing the fields of the sums of the strain rate tensor's horizontal components from the seismic data (Fig. 6) and the GPS data (Fig. 7) reveals an inconsistency for the Suusamyr depression: the GPS data shows a considerable crustal shortening in the horizontal plane, while the seismic data is indicative of a shear deformation. In the central part of the junction zone of...

show abstract

“…Деформации Тянь-Шаня. В работах [Zubovich et al, 2004[Zubovich et al, , 2007Kostyuk, 2009;Kostyuk et al, 2010;Kuzikov et al, 2009] были представлены результаты геодезических наблюдений GPS по данным региональной сети станций Южного Казахстана и Тянь-Шаня, дополненные группой GPS-пунктов сети НС РАН в г. Бишкек. Здесь GPS-станции располагались на меньших расстояниях, так как плотность сети для СТШ составляла около 20 км.…”

Section: латеральные деформации кровли коры по геофизическим даннымunclassified

On the specific state of crustal stresses in intracontinental orogens

Rebetsky¹

2015

Geodyn. Tectonophys.

View full text Add to dashboard Cite

The article presents a systematic review of the available tectonophysical data on the state of crustal uplifts and basins in intracontinental orogens. Based on results of the tectonophysical analysis of data on earthquake focal mechanisms for the Altai-Sayan and Northern Tien Shan regions, it is established that in many cases the crust in the basins and uplifts has antipodal structures, considering various types of the state of stresses. In the crust of the uplifts, maximum compression axes are usually sub-horizontal; in the crust of the basins, only the axis of the principal stress of minimum compression (i.e. maximum deviatoric extension) is sub-horizontal. These observations correlate well with estimations of deformations on the surface of the crust on the basis of the GPS-geodesy data, as well as with stress measurements taken directly on mining sites. The antipodal structures and physical fields in the crust of the uplifts and basins are not a random phenomenon. This suggests a common mechanism of deformation at the stage of active formation of the uplifts and basins. However, results of a similar tectonophysical analysis performed for the crust of the Pamir plateau and Tibet show that minimum compression stresses are sub-horizontal in these regions, and the geodynamic type of the state of stresses is determined as horizontal extension or horizontal shearing. This pattern contrasts sharply with the type of the state of stresses of horizontal compression in the crust of the mountain ranges around the plateau (the Himalayas, Kunlun, Tsilian Shan, Hindu Kush), as well as with the state of stresses of active orogenic structures of the Tien Shan and Altai-Sayan regions. Based on the stress values estimated for a range of geodynamic types of the state of stresses, it is estimated that additional compression stresses of the order of 5.4 kbar are required for the transition from horizontal extension to horizontal compression. If the regional strain rates currently recorded by the GPS-geodesy are taken into account, such additional stresses need to be applied for about 10 million years to fulfill the transition.

show abstract

Deformation of the Earth’s crust in the Northern Tien Shan according to the earthquake focal data and satellite geodesy

Cited by 12 publications

References 9 publications

Recent local geodynamic processes in the Penola Strait_Lemaire Channel fault area (West Antarctica)

Recent local geodynamic processes in the Penola Strait_Lemaire Channel fault area (West Antarctica)

Comparison of Crustal Deformation Rates Estimated From Seismic and GPS Data on the Bishkek Geodynamic Polygon

On the specific state of crustal stresses in intracontinental orogens

Contact Info

Product

Resources

About