{"title":"Assessment of Diagnostic Accuracy and Clinical Utility of DNA Methylation (5-mC) in Detecting Severity of Occupational Lead Exposure.","authors":"Ravibabu Kalahasthi, Vinay Kumar Adepu, Raju Nagaraju","doi":"10.1007/s12291-023-01138-z","DOIUrl":"10.1007/s12291-023-01138-z","url":null,"abstract":"<p><p>This study investigated the diagnostic accuracy (DA) and clinical utility (CU) of DNA methylation (5 methylcytosine) in occupational Pb-exposure from Pb based industry. Blood Lead levels (BLLs) were measured using the ICP-OES method. The total DNA methylation (5-mC) was quantified using ELISA method. Based on their BLLs, the Pb-exposed workers were categorised into three groups: low (< 10 µg/dL), moderate (10-30 µg/dL), and high exposure (> 30 µg/dL). DNA methylation (5-mC) was significantly lower in moderate and high Pb-exposure groups when compared to the low Pb-exposure group. Workers exposed to high levels of Pb-exposure, the DA variables of 5-mC showed that the sensitivity was 74.7% [95% CI 65.4-84.0], specificity was 69.6% [95% CI 50.8-88.4], positive predictive value (PPV) was 89.9% [95% CI 82.7-97.0], Postive likelihood ratio (LR+) was 2.454 [95% CI 1.3-4.6], and diagnostic odds ratio (DOR) is 6.3 [95% CI 6.5-7.7]. In moderate Pb-exposure, the DA variables of 5-mC revealed that the sensitivity is 64.9% [95% CI 55.2-74.5], the specificity is 69.6% [95% CI 50.8-88.4], the PPV is 89.7% [95% CI 82.5-97.0], the LR+ is 2.132 [95% CI 1.13-4.03], and the DOR is 4.2 [95% CI 3.6-5.7]. The high Pb-exposure group had higher DA metrics when compared to moderate Pb exposure. The clinical utility (CU+) of 5-mC was found to have good utility of 0.671 [95% CI 0.566-0.776] in the high Pb exposure group and fair utility of 0.582 [95% CI 0.470-0.694] in moderate Pb exposure group. In conclusion, DNA methylation (5mC) could be used as a predictive biomarker for high Pb-exposure.</p>","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":"12 1","pages":"572-578"},"PeriodicalIF":1.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11436711/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79273717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-09-01DOI: 10.1029/2022TC007721
D. Šilerová, B. Dyck, J. A. Cutts, K. Larson
{"title":"Long‐Lived (180 Myr) Ductile Flow Within the Great Slave Lake Shear Zone","authors":"D. Šilerová, B. Dyck, J. A. Cutts, K. Larson","doi":"10.1029/2022TC007721","DOIUrl":"https://doi.org/10.1029/2022TC007721","url":null,"abstract":"The Great Slave Lake shear zone (GSLsz) is a type example for deeply eroded continental transform boundaries located in the Northwest Territories, Canada. Formed during the oblique convergence of the Archean Rae and Slave cratons, the GSLsz has accommodated up to 700 km of dextral shear. Here we present the results of in situ U‐Pb apatite and titanite geochronology from 11 samples that were collected across the strike of the shear zone. Both geochronometers record a near‐continuous history of ductile shear during crustal cooling and exhumation that spans ca. 1920–1740 Ma. By integrating the geochronological data with structural and metamorphic observations across the structure, we propose a tectonic model for the shear zone that consists of three stages. The first stage (ca. 1920–1880 Ma) is characterized by strain accommodation along two coeval fault strands. During the second stage (ca. 1880–1800 Ma), ductile shear ceases along the northernmost fault strand and the locus of strain migrates southwards toward the hinterland of the Rae cratonic margin. In the third stage (ca. 1800–1740 Ma), ductile strain localizes back along the southern of the two original fault strands, after which the present‐day surface level of the shear zone transitions to brittle shear. Our results highlight both the significance of the lateral migration of the zone of active deformation in major crustal shear zones as well as the localization of strain along existing crustal structures.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49008882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-09-01DOI: 10.1029/2023TC007798
A. Testa, P. Boncio, S. Baize, F. Mirabella, S. Pucci, B. Pace, M. Riesner, C. Pauselli, M. Ercoli, L. Benedetti, A. Di Chiara, R. Civico
{"title":"Paleoseismological Constraints on the Anghiari Normal Fault (Northern Apennines, Italy) and Potential Implications for the Activity of the Altotiberina Low‐Angle Normal Fault","authors":"A. Testa, P. Boncio, S. Baize, F. Mirabella, S. Pucci, B. Pace, M. Riesner, C. Pauselli, M. Ercoli, L. Benedetti, A. Di Chiara, R. Civico","doi":"10.1029/2023TC007798","DOIUrl":"https://doi.org/10.1029/2023TC007798","url":null,"abstract":"The NE‐dipping Anghiari normal fault, bounding to the west the Sansepolcro basin in the Upper Tiber Valley (northern Apennines), is thought to be a synthetic splay of the Altotiberina low‐angle normal fault (LANF), an active ENE‐dipping extensional detachment whose seismogenic behavior is debated. In order to assess the Anghiari fault capability to break the surface during strong earthquakes and be the source of historical earthquakes, we acquired high resolution topographic data, performed field survey and geophysical investigations (Seismic reflection, Ground Penetrating Radar, Electrical Resistivity Tomography) and dug three paleoseismological trenches across different fault sections of the Anghiari fault. The acquired data reveal for the first time the Late Pleistocene to historical activity of the Anghiari fault, constraining the age of seven paleo‐earthquakes over the last 25 ka, the youngest of which is comparable with one of the poorly constrained historical earthquakes of the Sansepolcro basin. The yielded slip rate is >0.2 mm/yr averaged over the last 25 ka and the recurrence interval is about 2,500–3,200 years. An analysis of the anisotropy of the magnetic susceptibility performed in one of the paleoseismological trenches revealed an extensional stress field, continuously acting during the sedimentation of the entire trenched stratigraphy. Our results confirm the ability of the Anghiari fault to generate surface faulting earthquakes. In addition, if the Anghiari fault does sole at depth into the Altotiberina low‐angle normal fault, this LANF could also be seismogenic and generate M > 6.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45201252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Crustal‐Scale Seismic Reflection Profiling Constrains How the Paleo‐Asian Ocean Was Closed","authors":"Xiaomiao Tan, Jianbo Zhou, Xiao‐Fan Deng, Haiyan Wang, He‐Sheng Hou, Hui‐Lin Li, Rui Qi, Fan Xie, Rui Gao","doi":"10.1029/2023TC007921","DOIUrl":"https://doi.org/10.1029/2023TC007921","url":null,"abstract":"The Central Asian Orogenic Belt (CAOB) is the most significant accretionary orogenic belt since the Phanerozoic and the most ideal site for studying continental growth evolution processes. A 460‐km‐long high‐resolution crustal‐scale seismic reflection study was conducted across the eastern CAOB in North‐Central China to constrain the closure mode and location of the Paleo‐Asian Ocean, that is, the previous ocean of the CAOB. The resultant seismic reflection profile revealed opposite‐dipping reflectors in the northern and southern parts of the profile, which converge at the profile center to form an inverted U‐shaped reflector pattern near the crust–mantle transition zone beneath the Solonker Suture. The dipping reflectors represent bidirectional fossil subduction zones sloping to the north and south, and the convergence reflector pattern represents the ocean closure location. Integration of these results with available geological data facilitated model construction whereby Paleo‐Asian Ocean closure was accomplished by divergent subduction of the Paleo‐Asian oceanic plate, with northward subduction beneath the southern margin of the Mongolian Block and southward subduction beneath the northern margin of the North China Craton. The oceanic lithosphere contracted and deformed, yielding the observed inverted U‐shaped reflector pattern, representing Paleo‐Asian Ocean closure. This subsurface location lies beneath the Solonker Suture surface exposure, suggesting that this suture marks the ocean closure location, rather than the previously proposed Hegenshan–Heihe Suture to the north or Xar Moron Suture to the south. Our study suggests that divergently dipping subduction and associated accretion and magmatism may constitute the primary continental growth mode for accretionary‐type orogens.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43389887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-08-31DOI: 10.1029/2022tc007659
Sophie Pan, J. Naliboff, Rebecca Bell, Chris Jackson
{"title":"How do rift‐related fault network distributions evolve? Quantitative comparisons between natural fault observations and 3D numerical models of continental extension","authors":"Sophie Pan, J. Naliboff, Rebecca Bell, Chris Jackson","doi":"10.1029/2022tc007659","DOIUrl":"https://doi.org/10.1029/2022tc007659","url":null,"abstract":"Continental extension is primarily accommodated by the evolution of normal fault networks. Rifts are shaped by complex tectonic processes and it has historically been difficult to determine the key rift controls using only observations from natural rifts. Here, we use 3D thermo‐mechanical, high‐resolution (<650 m) forward models of continental extension to investigate how fault network patterns vary as a function of key rift parameters, including extension rate, the magnitude of strain weakening, and the distribution and magnitude of initial crustal damage. We quantitatively compare modelled fault networks with observations of fault patterns in natural rifts, finding key similarities in their along‐strike variability and scaling distributions. We show that fault‐accommodated strain summed across the entire 180 x 180 km study area increases linearly with time. We find that large faults do not abide by power‐law scaling as they are limited by an upper finite characteristic, ω0. Fault weakening, and the spatial distribution of initial plastic strain blocks, exert a key control on fault characteristics. We show that off‐fault (i.e. non‐fault extracted) deformation accounts for 30‐70% of the total extensional strain, depending on the rift parameters. As fault population statistics produce distinct characteristics for our investigated rift parameters, further numerical and observational data may enable the future reconstruction of key rifting parameters through observational data alone.This article is protected by copyright. All rights reserved.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":"1 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45260841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-08-23DOI: 10.1029/2022TC007698
A. Wölfler, R. Wolff, A. Hampel, R. Hetzel, I. Dunkl
{"title":"Phases of Enhanced Exhumation During the Cretaceous and Cenozoic Orogenies in the Eastern European Alps: New Insights From Thermochronological Data and Thermokinematic Modeling","authors":"A. Wölfler, R. Wolff, A. Hampel, R. Hetzel, I. Dunkl","doi":"10.1029/2022TC007698","DOIUrl":"https://doi.org/10.1029/2022TC007698","url":null,"abstract":"Austroalpine nappes in the Eastern European Alps have preserved the record of orogenies in the Cretaceous and Cenozoic but their cooling and exhumation history remains poorly constrained. Here we use low‐temperature thermochronology and thermokinematic modeling to unravel the exhumation history of the Austroalpine nappes in the Gurktal Alps. Our data reveal marked differences between the exhumation of units located at different positions within the nappe stack and relative to the Adriatic indenter. Units located at a high structural level and farther away from the indenter cooled through the zircon fission track closure temperature in the Late Cretaceous and have resided at depths of ≤5–6 km since the Oligocene, as indicated by apatite fission track ages of 35–30 Ma. Thermokinematic modeling constrained that these units experienced enhanced exhumation (∼0.60 km/Ma) between ∼99 and ∼83 Ma due to syn‐ to late‐orogenic Late Cretaceous extension. After a phase of slow exhumation (∼0.02 km/Ma), the exhumation rate increased to ∼0.16 km/Ma at ∼34 Ma due to the onset of the Europe‐Adria collision. In contrast, zircon fission track ages from units at a lower structural level and near the indenter indicate cooling during the Eocene; apatite fission track ages cluster at ∼15 Ma. These units were rapidly exhumed (∼0.76 km/Ma) from ∼44 to ∼39 Ma during an Eocene phase of shortening prior to the Europe‐Adria collision. After slow exhumation (∼0.13 km/Ma) between ∼39 and ∼18 Ma, the exhumation rate increased to ∼0.27 km/Ma in the wake of Miocene escape tectonics in the Eastern Alps.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41601260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-08-22DOI: 10.1029/2022TC007338
A. Filippova, V. Melnikova
{"title":"Crustal Stresses in the East Arctic Region From New Data on Earthquake Focal Mechanisms","authors":"A. Filippova, V. Melnikova","doi":"10.1029/2022TC007338","DOIUrl":"https://doi.org/10.1029/2022TC007338","url":null,"abstract":"East Arctic is a key region for understanding the current geodynamic pattern and lithospheric evolution of the whole Arctic. To close an evident gap in regional seismic data, we calculate source parameters for 103 earthquakes (Mw ≥ 4.2, 1990–2021) and compile a representative uniform data set including source depths, scalar seismic moments, moment magnitudes, and focal mechanisms. On its basis, crustal stresses are estimated within four blocks with the homogeneous stress field. Extension dominates along the Gakkel Ridge and over most of the Laptev Sea shelf. On the continent and east and west of the shelf, it is replaced by compression. The obtained results indicate that the spreading axis of the Gakkel Ridge does not continue to the Laptev Sea shelf and evidence for the Eurasian–North American plate boundary crosses the eastern Laptev Sea shelf and is likely to pass to the Chersky Range through the Yana Bay.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48864344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-08-19DOI: 10.1029/2023TC007792
Jun Ning, Yingde Jiang, K. Schulmann, Sheng Wang, Pengfei Li, Shuai Shi, H. Qiu
{"title":"Silurian‐Devonian Lithospheric Thinning and Thermally Softening Along the Northern Margin of the Tarim Craton: Geological Mapping, Petro‐Structural Analysis and Geochronological Constraints","authors":"Jun Ning, Yingde Jiang, K. Schulmann, Sheng Wang, Pengfei Li, Shuai Shi, H. Qiu","doi":"10.1029/2023TC007792","DOIUrl":"https://doi.org/10.1029/2023TC007792","url":null,"abstract":"While the western part of northern Tarim Craton has long been considered as a Paleozoic passive margin, a pronounced Silurian‐Devonian magmatism developed on eastern part of this margin may indicate different but active margin setting. In this contribution, detailed structural mapping, petro‐structural analysis, and geochronological investigations were conducted in the Korla area, eastern part of northern Tarim Craton. Three main generations of fabrics were recognized. The earliest pervasive fabric is an originally sub‐horizontal metamorphic S1 foliation that is in part associated with migmatization characterized by high temperature/low pressure metamorphic mineral assemblages, interpreted as reflecting crustal extension. S1 foliation was affected by D2 contraction forming regional‐scale F2 upright folds associated with sub‐vertical axial planar foliation S2. D3 is marked by development of NW‐SE oriented dextral fault, asymmetric mega‐folding of S2 and spaced NW‐SE‐striking S3 foliation, likely in response to dextral transpression. Geochronological data indicate that D1 extension occurred from ca. 420 to 410 Ma, D2 contraction started around 410 Ma and lasted till 400 Ma or later, and D3 transpression was ongoing around ∼370 Ma. Integrated with regional data, an updated geodynamic model is proposed by interpreting the Central Tianshan, South Tianshan and NE Tarim Craton as an early Paleozoic supra‐subduction system. We suggest that the Silurian‐Devonian event reflects thermal softening and horizontal stretching of the supra‐subduction crust, resulting in drifting of the Central Tianshan continental arc from the proto Tarim Craton in association with opening of the South Tianshan back‐arc basin in‐between.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44344853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-08-13DOI: 10.1029/2023TC007912
M. Braza, N. McQuarrie, D. Robinson, L. Webb
{"title":"Temperature, Deformation, and Mass Transfer in a Hot Orogen: Insights From Thermokinematic Forward Models for Far Western Nepal","authors":"M. Braza, N. McQuarrie, D. Robinson, L. Webb","doi":"10.1029/2023TC007912","DOIUrl":"https://doi.org/10.1029/2023TC007912","url":null,"abstract":"Exhumation and cooling pathways of mid‐crustal metamorphic rocks in the western Nepal Himalaya can be replicated by fold‐thrust belt structures with displacement localized along discrete décollements. New and published muscovite 40Ar/39Ar, zircon U‐Th/He, and apatite fission track cooling ages, peak temperature estimates, geologic mapping, and basin data are integrated with thermokinematic forward models to constrain the geometry, kinematics, and rates of shortening in far western Nepal. The best fit to peak temperatures, cooling ages, and basin accumulation data is achieved with a largely in‐sequence kinematic order, with out‐of‐sequence motion on the Ramgarh‐Munsiari thrust. Fast rates (∼20–40 mm/yr) are required during shortening on early, large displacement faults at ∼23–12 Ma and decrease to ∼10–15 mm/yr during formation of the Lesser Himalayan duplex until ∼1 Ma. Thermokinematic models highlight the relationship between peak temperature, geometry, and shortening on the large displacement Main Central and Ramgarh‐Munsiari thrusts. In the thermokinematic models, we observe a relationship between the location of frontal ramps for the faults that displace lower Lesser Himalayan units and the ∼375°C isotherm, immediately before the ramp becomes active. These correlations suggest that temperature exerts a first‐order control on thrust geometry in a hot orogen. Viable models highlight the position of active ramps, kinematic order of faults, timing of fault motion, and reduction in shortening rates that are required to reproduce the surface geology, basin accumulation, peak temperature conditions, and timing of exhumation. Cooling ages are far more sensitive to the age of fault motion than the rate of fault motion.","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45282517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TectonicsPub Date : 2023-08-11DOI: 10.1029/2022TC007654
T. Waldien, S. Roeske, R. Chatterjee, P. O’Sullivan, D. Stockli
{"title":"Suture Reactivation, Slip Partitioning, and a Protracted Strike‐Slip Rate Gradient in the Denali Fault System, Southern Alaska, USA","authors":"T. Waldien, S. Roeske, R. Chatterjee, P. O’Sullivan, D. Stockli","doi":"10.1029/2022TC007654","DOIUrl":"https://doi.org/10.1029/2022TC007654","url":null,"abstract":"Active strike‐slip fault systems commonly display along‐strike Quaternary slip rate gradients associated with fault bends and splay faults, which generate surface uplift by dip‐slip faulting or distributed “off fault” deformation. By analogy, the documentation of long‐term (107 yr) slip gradients on some continental strike‐slip fault systems implies long‐term coevolution of strike‐slip and dip‐slip fault systems. Here we leverage the observed ≥33 Myr right‐lateral slip gradient on the Denali fault, Alaska, USA to investigate the role of splay thrust systems in accommodating the slip gradient. We focus on the Broxson Gulch thrust system, which splays southwestward from the Denali fault in the eastern Alaska Range. Apatite and zircon (U‐Th)/He and fission‐track cooling ages from metasedimentary and metaplutonic rocks intersected by the thrust system record an along‐strike decrease in cooling ages commensurate with an increase in late Oligocene‐Neogene bedrock exhumation and shortening with proximity to the Denali fault. The dominant structure in the Broxson Gulch thrust system is the Valdez Creek fault, which is an upper crustal reactivation of the Valdez Creek shear zone–the main Late Cretaceous suture between western North America and outboard accreted arc terranes. After reactivation of the Valdez Creek shear zone at ca. 30 Ma, the thrust system grew by south‐vergent imbrication of the upper crust along thrust and reverse faults until at least 6 Ma. Incorporating results from the Broxson Gulch thrust system into the regional structural evolution of the Denali fault system reveals significant spatiotemporal heterogeneity in shortening adjacent to the Denali fault. Moreover, nearly all of the late Oligocene‐Neogene shortening south of the Denali fault was focused along reactivated terrane boundaries inherited from Mesozoic assembly of the North American Cordillera, and the spatial distribution of the inherited structures appears to control slip partitioning behavior of the Denali fault system across time scales ranging from 101 (historic seismicity) to 107 yr. The slip partitioning behavior of the Denali fault system highlights the mechanical importance of inherited structures leading to protracted shortening on splay thrust systems, which siphon slip from the master strike‐slip fault. We contend that the weakness of nearby reactivated terrane boundaries should be considered among other mechanisms commonly evoked to explain the partitioning behavior of continental strike‐slip fault systems (e.g., stress field rotation, obliquity angle, and strength of master strike‐slip fault).","PeriodicalId":22351,"journal":{"name":"Tectonics","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43345338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}