Segment Linkage Research Articles

Resistance to a DNA and a RNA virus in transgenic plants by using a single chimeric transgene construct

Tomato leaf curl Taiwan virus (ToLCTWV) and Tomato spotted wilt virus (TSWV) are two major tomato viruses that cause serious economic losses. In this study, a partial C2 gene from ToLCTWV and the middle half of the N gene of TSWV were fused as a chimeric transgene to develop multiple virus resistance in transgenic plants. This construct was introduced into Nicotiana benthamiana and tomato by Agrobacterium-mediated transformation. Several transgenic lines showed no symptom post agro-inoculation with ToLCTWV and displayed high resistance to TSWV. The detection of siRNAs indicated that the resistance was via RNA silencing. This study demonstrated that linkage of gene segments from two viruses with distinct genomic organization, one DNA and the other RNA, can confer multiple virus resistance in transgenic plants via gene silencing.

Active fault, fault growth and segment linkage along the Janauri anticline (frontal foreland fold), NW Himalaya, India

The 100 km long frontal foreland fold — the Janauri anticline in NW Himalayan foothills represents a single segment formed due to inter-linking of the southern (JS1) and the northern (JS2) Janauri segments. This anticline is a product of the fault related fold growth that facilitated lateral propagation by acquiring more length and linkage of smaller segments giving rise to a single large segment. The linked portion marked by flat-uplifted surface in the central portion represents the paleo-water gap of the Sutlej River. This area is comparatively more active in terms of tectonic activity, well justified by the occurrence of fault scarps along the forelimb and backlimb of the anticline. Occurrence of active fault scarps on either side of the anticline suggests that the slip accommodated in the frontal part is partitioned between the main frontal thrust i.e. the Himalayan Frontal Thrust (HFT) and associated back-thrust. The uplift in the piedmont zone along southern portion of Janauri anticline marked by dissected younger hill range suggests fore-landward propagation of tectonic activity along newly developed Frontal Piedmont Thrust (FPT), an imbricated emergent thrust branching out from the HFT system. We suggests that this happened because the southern segment JS1 does not linked-up with the northwestern end of Chandigarh anticline segment (CS). In the northwestern end of the Janauri anticline, due to no structural asperity the tectonic activity on HFT was taken-up by two (HF1 — in the frontal part and HF2 — towards the hinterland side) newly developed parallel active faults ( Hajipur Fault) branched from the main JS2 segment. The lateral propagation and movements along HF1 and HF2 resulted in uplift of the floodplain as well as responsible for the northward shift of the Beas River. GPR and trench investigations suggest that earthquakes during the recent past were accompanied with surface rupture. OSL (optical stimulated luminescence) dates from the trench suggests occurrence of at least two events during the recent historic past, with the latest — Event II during 1500 AD (?).

Genetic stability and linkage analysis of the 2009 influenza A(H1N1) virus based on sequence homology

The 2009 swine-origin Influenza A virus subtype H1N1 (S-OIV) is generally believed to be a mixture of human, bird and swine viruses, resulting from multiple reassortments. The evolutionary origin of the S-OIV is of high interest but still remains obscure. In order to understand the evolution of the new virus, we performed sequence homology, segment stability and segment linkage analysis, as well as analysis of the host and geographic distribution of the evolutionarily related viruses. Stability analysis demonstrated that segment 6 (NA) was the most unstable one, followed by segment 4 (HA), while the other 6 segments were relatively stable. Host and geographic distribution analysis indicated that all 8 segments of the new virus were closely related to those of swine influenza viruses circulating either in North America or in Eurasia. Segment linkage analysis showed that segments 1 (PB2), 2 (PB1), 3 (PA), 4 (HA), 5 (NP), and 8 (NS) are in linkage disequilibrium exclusively with North American swine influenza viruses, and segments 6 (NA) and 7 (M) are evolutionarily linked solely with Eurasian swine influenza viruses. Two North American swine strains and 2 Eurasian swine strains were identified as possible ancestors of S-OIV 2009. Based on the most recent linkage analysis with the updated influenza sequences, South Dakota avian strains were found to be the closest known relatives of S-OIV 2009.

Structural evolution of the Gediz Graben, SW Turkey: temporal and spatial variation of the graben basin

ABSTRACTThe structural evolution of the Miocene to Recent Gediz Graben is intimately related to the evolution of its southern margin. This margin is shaped by a time‐transgressive, composite structure that possesses flat‐ramp geometry with three separate dip domains: a low‐angle shallow segment; a steeper middle segment; and a low‐angle deeper segment. This geometry was probably produced by one of two mechanisms, which operated perpendicular to the general trend of the graben, resulting in gradual back‐rotation followed by abandonment of the shallow segment as it was dissected by the high‐angle normal fault(s). The geometry of the southern margin structure is not simple along‐strike. It includes broad undulations and discrete fault segments, developed by large‐scale fault growth processes through segment linkage. The along‐strike growth of the southern margin‐bounding structure is responsible for the composite character of the Gediz Graben and controls the observed stratigraphic variability. Two sub‐basins aligned with the major segments of the southern graben margin structure have been investigated. The Salihli and Alaşehir sub‐basins comprising 3000 m sedimentary thickness are separated by an intervening basement high, that is covered by a thin veneer of post‐Miocene sediments. The two sub‐basins, which evolved as isolated basins during most of the graben history, amalgamated during post‐Miocene time to form the composite configuration of the graben. There is a general east to west trend of growth for the Gediz Graben.

Evolution of basin architecture in an incipient continental rift: the Cenozoic Most Basin, Eger Graben (Central Europe)

ABSTRACTThe Oligo‐Miocene Most Basin is the largest preserved sedimentary basin within the Eger Graben, the easternmost part of the European Cenozoic Rift System (ECRIS). The basin is interpreted as a part of an incipient rift system that underwent two distinct phases of extension. The first phase, characterised by NNE–SSW‐ to N–S‐oriented horizontal extension between the end of Eocene and early Miocene, was oblique to the rift axis and caused evolution of a fault system characterised by en‐échelon‐arranged E–W (ENE–WSW) faults. These faults defined a number of small, shallow initial depocentres of very small subsidence rates that gradually merged during the growth and linkage of the normal fault segments. The youngest part of the basin fill indicates accelerated subsidence caused probably by the concentration of displacement at several major bounding faults. Major post‐depositional faulting and forced folding were related to a change in the extension vector to an orthogonal position with respect to the rift axis and overprinting of the E–W faults by an NE–SW normal fault system. The origin of the palaeostress field of the earlier, oblique, extensional phase remains controversial and can be attributed either to the effects of the Alpine lithospheric root or (perhaps more likely because of the dominant volcanism at the onset of Eger Graben formation) to doming due to thermal perturbation of the lithosphere. The later, orthogonal, extensional phase is explained by stretching along the crest of a growing regional‐scale anticlinal feature, which supports the recent hypothesis of lithospheric folding in the Alpine–Carpathian foreland.

South Virgin–White Hills detachment fault system of SE Nevada and NW Arizona: Applying apatite fission track thermochronology to constrain the tectonic evolution of a major continental detachment fault

The South Virgin–White Hills detachment (SVWHD) in the central Basin and Range province with an along‐strike extent of ∼60 km is a major continental detachment fault system. Displacement on the SVWHD decreases north to south from ∼17 to <6 km. This is accompanied by a change in fault and footwall rock type from mylonite overprinted by cataclasite to chlorite cataclasite and then fault breccia reflecting decreasing fault displacement and footwall exhumation. Apatite fission track (AFT) thermochronology was applied both along‐strike and across‐strike to assess this displacement gradient. The overall thermal history reflects Laramide cooling (∼75 Ma) and then rapid cooling beginning in the late early Miocene. Age patterns reflect some complexity but extension along the SVWHD appears synchronous with rapid cooling initiated at ∼17 Ma due to tectonic exhumation. Slip rate is more rapid (∼8.6 km/Ma) in the north compared to ∼1 km/Ma in the south. The displacement gradient results from penecontemporaneous along‐strike motion and formation of the SVWHD by linkage of originally separate fault segments that have differential displacements and hence differential slip rates. East–west transverse structures likely play a role in linkage of different fault segments. The preextension paleogeothermal gradient is well constrained in the Gold Butte block as 18–20°C/km. We present a new thermochronologic approach to constrain fault dip during slip, treating the vertical exhumation rate and the slip as vectors, with the angle between them used to constrain fault dip during slip through the closure temperature of a particular thermochronometer. AFT data from the western rim of the Colorado Plateau constrain the initiation of timing of cooling associated with the Laramide Orogeny at ∼75 Ma, and a reheating event in the late Eocene/early Oligocene associated with burial by sediments (“rim gravels”) most likely shed from the Kingman High to the west of the plateau.

The role of inherited extensional fault segmentation and linkage in contractional orogenesis: a reconstruction of Lower Cretaceous inverted rift basins in the Eastern Cordillera of Colombia

ABSTRACTLower Cretaceous early syn‐rift facies along the eastern flank of the Eastern Cordillera of Colombia, their provenance, and structural context, reveal the complex interactions between Cretaceous extension, spatio‐temporal trends in associated sedimentation, and subsequent inversion of the Cretaceous Guatiquía paleo‐rift. South of 4°30′N lat, early syn‐rift alluvial sequences in former extensional footwall areas were contemporaneous with fan‐delta deposits in shallow marine environments in adjacent hanging‐wall areas. In general, footwall erosion was more pronounced in the southern part of the paleorift. In contrast, early syn‐rift sequences in former footwall areas in the northern rift sectors mainly comprise shallow marine supratidal sabkha to intertidal strata, whereas hanging‐wall units display rapid transitions to open‐sea shales. In comparison with the southern paleo‐rift sector, fan‐delta deposits in the north are scarce, and provenance suggests negligible footwall erosion. The southern graben segment had longer, and less numerous normal faults, whereas the northern graben segment was characterized by shorter, rectilinear faults. To the east, the graben system was bounded by major basin‐margin faults with protracted activity and greater throw as compared with intrabasinal faults to the west. Intrabasinal structures grew through segment linkage and probably interacted kinematically with basin‐margin faults. Basin‐margin faults constitute a coherent fault system that was conditioned by pre‐existing basement fabrics. Structural mapping, analysis of present‐day topography, and balanced cross sections indicate that positive inversion of extensional structures was focused along basin‐bounding faults, whereas intrabasinal faults remained unaffected and were passively transported by motion along the basin‐bounding faults. Thus, zones of maximum subsidence in extension accommodated maximum elevation in contraction, and former topographic highs remained as elevated areas. This documents the role of basin‐bounding faults as multiphased, long‐lived features conditioned by basement discontinuities. Inversion of basin‐bounding faults was more efficient in the southern than in the northern graben segment, possibly documenting the inheritance and pivotal role of fault‐displacement gradients. Our observations highlight similarities between inversion features in orogenic belts and intra‐plate basins, emphasizing the importance of the observed phenomena as predictive tools in the spatiotemporal analysis of inversion histories in orogens, as well as in hydrocarbon and mineral deposits exploration.

Structural geology and 4D evolution of a half-graben: New digital outcrop modelling techniques applied to the Nukhul half-graben, Suez rift, Egypt

LIDAR-based digital outcrop mapping, in conjunction with a new surface modelling approach specifically designed to deal with outcrop datasets, is used to examine the evolution of a half-graben scale normal fault array in the Suez rift. Syn-rift deposition in the Nukhul half-graben was controlled by the graben-bounding Nukhul fault. The fault can be divided into four segments based on the strike of the fault, the morphology of hangingwall strata, and the variation in throw along strike. The segments of the fault became geometrically linked within the first 2.5 m.y. of rifting, as evidenced by the presence of early syn-rift Abu Zenima Formation strata at the segment linkage points. Fault-perpendicular folds in the hangingwall related to along-strike variations in throw associated with precursor fault segments persist for a further 1.8 m.y. after linkage of the segments, suggesting that the fault remains kinematically segmented. We suggest this occurs because of sudden changes in fault strike at the segment linkage points that inhibit earthquake rupture propagation, or because displacement is geometrically inhibited at fault linkage points where the orientation of the intersection line of the segments is significantly different from the orientation of the slip vector on the fault system. Length/throw plots and throw contour patterns for minor faults show that some faults initiated in pre-rift strata, whereas late east-striking faults initiated in the syn-rift basin fill. The late initiating faults are spatially associated with the east-striking Baba–Markha fault, which was active throughout the rift history, but developed as a transfer fault between major block-bounding fault systems around 6–7 Ma after rift initiation.

Fault growth and propagation during incipient continental rifting: Insights from a combined aeromagnetic and Shuttle Radar Topography Mission digital elevation model investigation of the Okavango Rift Zone, northwest Botswana

Digital Elevation Models (DEM) extracted from the Shuttle Radar Topography Mission (SRTM) data and high‐resolution aeromagnetic data are used to characterize the growth and propagation of faults associated with the early stages of continental extension in the Okavango Rift Zone (ORZ), northwest Botswana. Significant differences in the height of fault scarps and the throws across the faults in the basement indicate extended fault histories accompanied by sediment accumulation within the rift graben. Faults in the center of the rift either lack topographic expressions or are interpreted to have become inactive, or have large throws and small scarp heights indicating waning activity. Faults on the outer margins of the rift exhibit either (1) large throws or significant scarp heights and are considered older and active or (2) throws and scarp heights that are in closer agreement and are considered young and active. Fault linkages between major fault systems through a process of “fault piracy” have combined to establish an immature border fault for the ORZ. Thus, in addition to growing in length (by along‐axis linkage of segments), the rift is also growing in width (by transferring motion to younger faults along the outer margins while abandoning older faults in the middle). Finally, utilization of preexisting zones of weakness allowed the development of very long faults (>100 km) at a very early stage of continental rifting, explaining the apparent paradox between the fault length versus throw for this young rift. This study clearly demonstrates that the integration of the SRTM DEM and aeromagnetic data provides a 3‐D view of the faults and fault systems, providing new insight into fault growth and propagation during the nascent stages of continental rifting.

Spatial release from energetic and informational masking in a selective speech identification task

A masker can reduce target intelligibility both by interfering with the target's peripheral representation ("energetic masking") and/or by causing more central interference ("informational masking"). Intelligibility generally improves with increasing spatial separation between two sources, an effect known as spatial release from masking (SRM). Here, SRM was measured using two concurrent sine-vocoded talkers. Target and masker were each composed of eight different narrowbands of speech (with little spectral overlap). The broadband target-to-masker energy ratio (TMR) was varied, and response errors were used to assess the relative importance of energetic and informational masking. Performance improved with increasing TMR. SRM occurred at all TMRs; however, the pattern of errors suggests that spatial separation affected performance differently, depending on the dominant type of masking. Detailed error analysis suggests that informational masking occurred due to failures in either across-time linkage of target segments (streaming) or top-down selection of the target. Specifically, differences in the spatial cues in target and masker improved streaming and target selection. In contrast, level differences helped listeners select the target, but had little influence on streaming. These results demonstrate that at least two mechanisms (differentially affected by spatial and level cues) influence informational masking.

Evolution of the geometry of normal faults in the Oligocene volcanic field of the Mesa Central, Mexico

We document that the direction of fault traces and the long axis of volcanic domes show a similar distribution, which indicates that the normal faults controlled in some way the location of volcanic rocks. In this study we analyze the evolution of the faults from a geometric point of view, without considerations about the volcanic processes. Bed tilt was controlled by fault block rotation with continuous fault activity. Multi-peak profi les of bed tilt along the fault strike and evident corrugation of the fault traces in the study area should be partly due to segment linkage during fault evolution. Some normal faults are associated with mode I fracture mechanism, whereas some other faults are due to mode II fracture mechanism according to the calculated initial dips. The plot of maximum fault displacement (D) versus trace length (L) is very scattered. Faults with D/L ratios larger than 0.1 and smaller than 0.1 can be distinguished; these two fault groups are produced by the effects of fault evolution and sampling. The principal factor infl uencing D/L ratios is the interaction and linkage among the faults. In addition, fault block rotation, fault initial mechanism, lithology of volcanic rocks, and denudation are other factors.

Two‐dimensional distinct element modeling of the structure and growth of normal faults in multilayer sequences: 1. Model calibration, boundary conditions, and selected results

The distinct element method is used for modeling the growth of normal faults in layered sequences. The models consist of circular particles that can be bonded together with breakable cement. Size effects of the model mechanical properties were studied for a constant average particle size and various sample widths. The study revealed that the bulk strength of the model material decreases with increasing sample size. Consequently, numerical lab tests and the associated construction of failure envelopes were performed for the specific layer width to particle diameter ratios used in the multilayer models. The normal faulting models are composed of strong layers (bonded particles) and weak layers (nonbonded particles) that are deformed in response to movement on a predefined fault at the base of the sequence. The modeling reproduces many of the geometries observed in natural faults, including (1) changes in fault dip due to different modes of failure in the strong and weak layers, (2) fault bifurcation (splaying), (3) the flexure of strong layers and the rotation of associated blocks to form normal drag, and (4) the progressive linkage of fault segments. The model fault zone geometries and their growth are compared to natural faults from Kilve foreshore (Somerset, United Kingdom). Both the model and natural faults provide support for the well‐known general trend that fault zone width increases with increasing displacement.

Characterization of strike-slip fault–splay relationships in sandstone

We document the length and angular relationships between strike-slip faults and their splays. The data indicate that the maximum splay length is correlated to the fault length by a power law but shows little correlation with the fault slip magnitude. The kink angle between faults and their splays is small for isolated faults (average ∼20°) and systematically larger for mechanically interacting faults (average ∼50°). Analytical models predict that splay length decreases with increasing confinement under biaxial compression. 2D numerical models of isolated faults show that small kink angles correspond to small values of the angle between the fault and the maximum compression ( β) whereas large kink angles require greater β values. Similar models of interacting faults confirm the critical role of β on the kink angles and suggest that fault overlap and fault separation can also induce important variations in the kink angles. Our results provide a basis for a better understanding of fault segment linkage via splaying process and for a better assessment of the maximum thickness of fault damage zones. The results may also help to predict the length and orientation of secondary faults formed by splaying associated with first order faults with resolvable slip magnitude in the subsurface.

Quantitative study of the deformation at Southern Explorer Ridge using high-resolution bathymetric data

We present preliminary results of a morphological study of the summit of the Southern Explorer Ridge (SER). The SER is an inflated intermediate-rate spreading center located in the northeast Pacific off the West coast of Canada, that hosts a large hydrothermal vent complex known as “Magic Mountain”. A quantitative assessment of faulting on the axial summit graben floor close to the ridge summit is accomplished through the analysis of high-resolution, near-bottom, bathymetric data. These data were acquired using a multibeam system mounted on an autonomous underwater vehicle operated a few tens meters above the seafloor. Structural mapping reveals numerous subvertical fissures and normal faults that nucleated from tension fissures. The ratio between the length and the maximum scarp height of normal faults is not constant contrary to what is generally observed on subaerial faults, highlighting the probable importance of fault segment linkage and fault growth processes within the relatively thin brittle layer. Populations of small faults exhibit an exponential size-frequency distribution that reflects the importance of linkage in the fault growth history and the relatively large amount of tectonic strain (3.7 to 18.4%) accommodated by the normal faults. We propose that the 500 to 600-m wide and ∼ 60-m deep asymmetric axial summit graben of the SER formed due to magma chamber deflation as well as normal faulting that initiated on the present eastern border of the graben. We find a well-defined geographic distribution in the types of lava flows, which indicates a general decrease of the eruption rate through time. We also find that the “Magic Mountain” hydrothermal field is located in the vicinity of the large eastern axial summit graben bounding fault whose dimensions suggest it may reach to the brittle ductile-transition depth. This fault likely has provided an efficient physical pathway for fluids from the subsurface to the seafloor for a significant period of time thus allowing the hydrothermal system to grow and mature.

Segment linkage and the state of stress in transtensional transfer zones: field examples from the Pannonian Basin

Abstract Metre- to kilometre-scale en échelon strike-slip faults were mapped at the 1:10 000 scale in the Gánt mining area of the Vértes Hills in central Hungary. Good exposures allow detailed observation of brittle structures within the transfer zones of the overstepping fault segments. The strike-slip segments are subvertical to steeply dipping, with a rake of 20–30° accommodating a noticeable dip-slip. Displacement transfer between strike-slip faults was achieved through transtensional relay ramps, which represent a specific type of transfer zone. The breaching faults are oblique-normal or pure normal types. Their strike, dip and the obliquity of their striae change systematically. This occurred in order to accommodate extension across the relay ramp. Low-angle connecting faults occur at a high angle to the main fault, and form preferentially when the striae approach the orientation of the strike of the main fault. Slip vectors on the main and secondary connecting fault planes are subparallel, so defining a coherently moving hanging wall. A stress-inversion method was applied for the main fault segments, which characterize a state of stress of regional significance. Calculations were performed for the whole data-sets, including data for the guided connecting faults of the transtensional relay ramps, even though, in theory, stress inversion is not realistic for faults with a guided slip. Indeed, calculations gave a state of stress that is differs from that of the regional stress state. The results should be a warning to geologists that fault geometry has to be clarified in overstepping fault arrays before using the data-set for fault-slip inversion.

Geometric and kinematic controls on the internal structure of a large normal fault in massive limestones: The Maghlaq Fault, Malta

The Maghlaq Fault is a large, left-stepping normal fault (displacement >210 m) cutting the Oligo-Miocene pre- to syn-rift carbonates of SW Malta. Two principal slip zones separate the deformed rocks of the fault zone from the undeformed wall rocks. Fault rocks derived from fully lithified, pre- to early syn-rift sediments comprise relatively continuous fine-grained veneers of cataclasite and localised fault-bound lenses of wall rock, occurring over a range of scales, which are commonly brecciated. The lenses result from the linkage of slip surfaces, the inclusion of asperities and the formation of Riedel shears within the fault zone. In contrast, fault rock incorporated from unlithified syn-rift sediments comprise relatively continuous veils of rock that deformed in a ductile manner. Anomalously thick parts of the fault zone with highly complex structure and content are associated with breached relay zones, branch-lines and bends; these structures represent progressive stages of fault segment linkage. The progressive evolution and bypassing of fault zone complexities to form a smoother and more continuous active fault surface, results in complex fault rock distributions within the fault zone. Segment linkage structures have high fracture densities which combined with their significant vertical extents suggest they are potentially important up-fault fluid flow conduits.

Spacing and linkage of confined normal faults: Importance of mechanical thickness

In this paper we present the results of the analysis of fault spacing from a population of faults confined to a 4.5 m thick mechanical layer. We demonstrate the control of a discrete layer on the specific geometry of a so‐called “domino‐style” or “bookshelf” fault population. The fault population shows a logarithmic‐normal frequency distribution of fault spacing, with a minimum value of spacing S* (∼0.25 layer thickness), revealing a nearly regular spacing distribution between the “long faults” (i.e., length greater than height), which are confined within the layer. We also observe an upper limit of fault linkage at relay ramp close to the minimum value of spacing S*, after which free overlapping between faults having the same dip direction is allowed. On the basis of field observations, we simulate the quasi‐static displacement‐related Coulomb shear stress perturbation of faults of various aspect ratios (length/height). The models show that on faults that increase in aspect ratio with a constant height (as expected for the confined faults), the horizontal extent of the local stress reduction tends to localize at a constant distance from the fault surface close to S*. For the studied case, the correspondence between the models and the field data suggests that the limited extent of the stress reduction around the confined faults controls fault spacing and fault ability to link at relay ramps. Both field data collection from different scales and modeling suggest that fault spacing in confined fault populations is linearly related to the mechanical layer thickness. We therefore highlight the importance of the thickness of layers confining faults in the evaluation of interaction, linkage and propagation of active fault segments over a broad range of scales.

A human body model for movement analysis using optoelectronic system

Human motion analysis asks frequently for determination of kinetic and kinematic data. This work proposes method to model human body as a linkage of rigid segments and to compute so called body segment parameters (BSP). Calculated BSP combined with 3D optoelectronic (kinematic) system data allow also kinetic analysis of human motion. Proposed body model is based on Helen-Hayes protocol. Modifications are introduced which makes it more robust to analyze movements where ASIS markers are usually hidden from camera, such as running, jumping etc. Moreover, alternative way of computing anthropometric measurements, needed for computation of BSP, is suggested via additional marker set. It is believed that these extra markers are acceptable compromise which in turn saves preparation time for patient in comparison where anthropometric measurements are obtained with various tape measures and calipers. Ultimate accuracy of inverse dynamic values is highly dependent on accuracy of BSP and 3D reconstruction. The later one is in turn greatly influenced by system calibration, i.e. cameras parameters computation. Another part of this work brings up the issue of calibration. A method to calibrate 3D optoelectronic system was proposed which exploits certain geometric entities defined within it, i.e. it takes advantage of orthogonal calibration tools. Proposed method simplifies typical camera calibration procedure of 3D kinematic systems. Validation of proposed body model has been successfully undertaken by comparing results with widely accepted model which uses Helen-Hayes protocol. Additionally validation is preformed through check of segments power calculation in two different ways: direct computation and derivation of total segment energies. Validation of proposed camera calibration has been carried out through reconstruction and analysis of points in space which position, i.e. mutual distance was known with high degree of accuracy in advance. Obtained accuracy is quite comparable, if not even better, with commercially available 3D kinematic systems.

Thrust-fault growth and segment linkage in the active Ostler fault zone, New Zealand

Thrust faulting is a fundamental mode of crustal deformation, yet many of the key geometrical attributes of thrust faults and the controls on fault rupture, growth, and linkage remain poorly resolved. Numerous surface-rupturing thrust faults cut through upper Quaternary glacial outwash terraces within the Ostler Fault zone, an active thrust system in the Southern Alps, New Zealand. We use these deformed marker surfaces to define the three-dimensional deformation field associated with their surface expression and to map displacement and length on ∼40 fault segments. Displacement transfer across two fault segment arrays occurs in distinctly different styles. In one, displacement is transferred between en échelon fault segments to produce a smooth, linear displacement gradient. In the other, large-scale folding and a population of small faults transfer displacement between two non-overlapping fault segments, with a residual displacement minimum within the transfer zone. Size distribution of fault-segment length and maximum displacement follow a power-law scaling relationship. Maximum displacement ( D max) scales linearly with and represents ∼1% of segment trace length ( L). D max/ L data from the segments of the Ostler Fault zone display similar scaling to a global fault dataset. This similarity is surprising, given that the observed displacements along the Ostler Fault represent only 20 ky of slip on fault segments that are likely to be many times older.

Growth of syndepositional faults in carbonate strata: Upper Permian Capitan platform, New Mexico, USA

The Upper Permian Capitan platform, New Mexico, is cut by syndepositional faults and fractures. These are parallel to platform margin and cluster within strata that steepen and thicken abruptly into the basin. Faults are steep, dip-slip, have measurable displacements of up to 24 m, are typically associated with growth strata, and mostly tip-out blindly within the platform. Basinward-throwing faults are typically reverse, and are steeper than shelfward-throwing faults, which have normal geometry. The sense of displacement across some initially basinward-throwing faults changed as they developed. These patterns indicate that faults were rotated as they grew. Synkinematic rotation of faults is interpreted to have occurred due to syndepositional, compaction-driven, down-to-basin tilting of the Capitan platform. Faults grew through interaction with inherited fractures and by segment linkage. Vertically separated fault segments had a tendency to grow downward to link with underlying segments, thus promoting accumulation of displacement across faults without vertical propagation of fault tips. Four fault types are distinguished on the basis of structures associated with their upper terminations: (I) faults breaking free surface, (II) faults tipping out within non-folded growth strata, (III) faults tipping out below growth monoclines, and (IV) buried faults with no expression on free surface. Fault tips evolved from one type into another in response to variations in the rates of fault growth and deposition. Fault-tip structures also vary laterally over distance of 750–1400 m, inferably as a result of variable distances from fault centres.