Journal articles: 'Geology, Structural Victoria, Southeastern'

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Bestani, Lucie, Nicolas Espurt, Juliette Lamarche, Marc Floquet, Jean Philip, Olivier Bellier, and Fabrice Hollender. "Structural style and evolution of the Pyrenean-Provence thrust belt, SE France." Bulletin de la Société Géologique de France 186, no. 4-5 (July 1, 2015): 223–41. http://dx.doi.org/10.2113/gssgfbull.186.4-5.223.

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AbstractThe Pyrenean-Provence fold-thrust belt is characterized by a geological complexity arising from superimposed tectonic history and the propagation of the deformation through a heterogeneous mechanical substratum inherited from Paleozoic and Mesozoic times. The construction of a regional balanced cross section together with field data show that the thrust system of the southeastern Provence region is characterized by a mixed thick- and thin-skinned tectonic style related to the inversion of deep-seated late Paleozoic-Triassic extensional structures and the décollement of the Mesozoic-Cenozoic sedimentary cover above Triassic series. Earliest Cenomanian restoration state highlights the northward pinched-out of the Lower Cretaceous sedimentary series above the main long-wavelength Durance High uplift. Latest Santonian restoration state indicates a southward tilting of ~2° of the basin attributed to the initial growth of the Pyrenean-Provence prism controlling the external flexure of the foreland. Thrusts propagation in the northern part of the Pyrenean-Provence fold-thrust belt was recorded to be synchronous during latest Cretaceous to Eocene time and produced a ~7° southward basin tilting. This major tilting is attributed to the tectonic inversion and basement thrust stacking of the Cap Sicié-Sainte Baume units. Cross section balancing shows a total horizontal basement shortening of 40 km (~35 %) across the Pyrenean-Provence foreland. The main part of this shortening (~37 km) was accommodated by thick-skinned thrusts involving basement south of the Arc syncline. ~5 km of shortening were accommodated northward by the Arc syncline and eastern Sainte-Victoire thin-skin structures, resulting from slip transferred from the deep thick-skinned intercutaneous thrust wedge. Finally we interpret salt tectonic structures of the southeastern Provence as passive diapirism growth during Jurassic to late Cretaceous time, and then reactivated during Pyrenean-Provence compression. Late normal faulting related to hypothetical reactive diapirism during the Oligocene extension episode was predominantly localized above inherited salt structures and probably controlled by inherited basement faults.

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Clemens, J. D., and G. Stevens. "S- to I- to A-type magmatic cycles in granitic terranes are not globally recurring progressions. The cases of the Cape Granite Suite of Southern Africa and central Victoria in southeastern Australia." South African Journal of Geology 124, no. 3 (September 1, 2021): 565–74. http://dx.doi.org/10.25131/sajg.124.0007.

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Abstract Recurring progression from S- to I- to A-type granites has been proposed for a subset of granitic rocks in eastern Australia. The wider applicability and the validity of this idea is explored using the Cape Granite Suite (CGS) of South Africa and the granitic and silicic volcanic rocks of central Victoria, in southeastern Australia. Within the CGS there is presently little justification for the notion that there is a clear temporal progression from early S-type, through I-type to late A-type magmatism. The I- and S-type rocks are certainly spatially separated. However, apart from a single slightly older pluton (the Hoedjiespunt Granite) there is no indication that the S- and I-type granites are temporally distinct. One dated A-type granitic sample and a syenite have poorly constrained dates that overlap with those of the youngest S-type granites. In central Victoria, the granitic magma types display neither a spatial separation nor a temporal progression from one type to another. All magma varieties are present together and were emplaced within a far narrower time window than in the CGS. Thus, a progression may or may not exist in a particular region, and the occurrence of such a progression does not hold true even in a part of southeastern Australia, which afforded the type example. Thus, the idea that, globally, there should be a progression from S- to I- to A-type magmatism is unjustified. The critical factor in determining the temporal relationship between granitic magmas of different types is probably the compositional structure of the deep crust in a particular region, a reflection of how the individual orogen was assembled. In turn, this must reflect significant differences in the tectonic settings.

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Turko, Molly, and Shankar Mitra. "Macroscopic structural styles in the southeastern Anadarko Basin, southern Oklahoma." Marine and Petroleum Geology 125 (March 2021): 104863. http://dx.doi.org/10.1016/j.marpetgeo.2020.104863.

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Webb, J. A., D. Fabel, B. L. Finlayson, M. Ellaway, Li Shu, and H. P. Spiertz. "Denudation chronology from cave and river terrace levels: the case of the Buchan Karst, southeastern Australia." Geological Magazine 129, no. 3 (May 1992): 307–17. http://dx.doi.org/10.1017/s0016756800019245.

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AbstractDetailed mapping of surface and underground karst features at Buchan, in eastern Victoria, has shown that the three river terraces along the Buchan River can be correlated with three levels of epiphreatic development in the nearby caves. Each level represents a stillstand in the denudational history of the area. Uranium series dating of speleothems and palaeomagnetic studies of cave sediments indicate that all three stilistands are more than 730 ka old. The periods of incision separating the stillstands were probably the result of active tectonic uplift. This contrasts with some northern parts of the Southeastern Highlands, which have been stable since the Eocene. The overall amount of incision and uplift at Buchan is small, indicating that the majority of scarp retreat in this section of the highlands must have occurred earlier. The denudation history of the Buchan area over the last 730 ka has seen only 2–3 m of incision, despite the major climatic and sea-level changes that have occurred in that time. Whereas most karst landscapes in the Northern Hemisphere have been extensively modified during the late Pleistocene, the Buchan karst was little affected, and its geomorphology has an older origin.

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Kondor, Henrietta, and Tivadar M Tóth. "Contrasting metamorphic and post-metamorphic evolutions within the Algyő basement high (Tisza Mega-unit, SE Hungary). Consequences for structural history." Central European Geology 64, no. 2 (May 29, 2021): 91–112. http://dx.doi.org/10.1556/24.2021.00004.

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AbstractThe Algyő High (AH) is an elevated crystalline block in southeastern Hungary covered by thick Neogene sediments. Although productive hydrocarbon reservoirs are found in these Neogene sequences, numerous fractured reservoirs also occur in the pre-Neogene basement of the Pannonian Basin. Based on these analogies, the rock body of the AH might also play a key role in fluid storage and migration; however, its structure and therefore the reservoir potential is little known. Based on a comprehensive petrologic study in conjunction with analysis of the spatial position of the major lithologies, the AH is considered to have been assembled from blocks with different petrographic features and metamorphic history. The most common lithologies of garnet-kyanite gneiss and mica schist associated with garnetiferous amphibolite are dominant in the northwestern and southeastern parts of the AH. The first regional amphibolite facies metamorphism of the gneiss and mica schist was overprinted by a contact metamorphic (metasomatic) event during decompression in the stability field of kyanite. Garnet-bearing amphibolite experienced amphibolite facies peak conditions comparable with the host gneiss. Regarding the similarities in petrologic features, the northwestern and southeastern parts of the area represent disaggregated blocks of the same rock body. The central part of the AH area is characterized by an epidote gneiss-dominated block metamorphosed along with a greenschist-facies retrograde pathway as well as a chlorite schist-dominated block formed by greenschist-facies progressive metamorphism. The independent evolution of these two blocks is further confirmed by the presence of a propylitic overprint in the chlorite schists. The different metamorphic blocks of the northwestern, southeastern and central parts of the AH probably became juxtaposed along post-metamorphic normal faults developed due to extensional processes. The supposed brittle structural boundaries between the blocks could have provided hydrocarbon migration pathways from the adjacent over-pressured sub-basins, or could even represent suitable reservoirs.

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Matchan, Erin L., David Phillips, Fred Jourdan, and Korien Oostingh. "Early human occupation of southeastern Australia: New insights from 40Ar/39Ar dating of young volcanoes." Geology 48, no. 4 (February 6, 2020): 390–94. http://dx.doi.org/10.1130/g47166.1.

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Abstract In Australia, the onset of human occupation (≥65 ka?) and dispersion across the continent are the subjects of intense debate and are critical to understanding global human migration routes. New-generation multi-collector mass spectrometers capable of high-precision 40Ar/39Ar dating of young (<500 ka) samples provide unprecedented opportunities to improve temporal constraints of archaeological events. In southeastern Australia, a novel approach to improving understanding of occupation involves dating key volcanic eruptions in the region, referenced to stone artifacts and Aboriginal oral traditions. The current study focuses on two monogenetic volcanoes in the Newer Volcanic Province of southeastern Australia: Budj Bim (previously Mount Eccles) and Tower Hill. Budj Bim and its surrounding lava landforms are of great cultural significance and feature prominently in the oral traditions of the Gunditjmara people. Tower Hill is of archaeological significance due to the occurrence of a stone tool beneath tephra. 40Ar/39Ar eruption ages of 36.9 ± 3.1 ka (95% confidence interval) and 36.8 ± 3.8 ka (2σ) were determined for the Budj Bim and Tower Hill volcanic complexes, respectively. The Tower Hill eruption age is a minimum age constraint for human presence in Victoria, consistent with published optically stimulated luminescence and 14C age constraints for the earliest known occupation sites in Tasmania, New South Wales, and South Australia. If aspects of oral traditions pertaining to Budj Bim or its surrounding lava landforms reflect volcanic activity, this could be interpreted as evidence for these being some of the oldest oral traditions in existence.

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Geissler, Paul E. "Seismic reflection profiling for groundwater studies in Victoria, Australia." GEOPHYSICS 54, no. 1 (January 1989): 31–37. http://dx.doi.org/10.1190/1.1442574.

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Experimental seismic reflection profiling was employed for groundwater studies in southeastern Australia. Equipment consisted of a simple engineering seismograph and tape recorder, and data reduction was carried out on a minicomputer using a graphics‐based processing system specifically written for the project. The investigation area is the site of a proposed induced groundwater recharge scheme in which surface water would be diverted to infiltrate aquifers outcropping several kilometers from a bore field which supplies up to half of the drinking water for the city of Geelong. The unconsolidated Tertiary aquifers of the region are known to be interrupted in places by steep normal and reverse faults. Since similar faulting had been inferred along the proposed recharge avenue, the objective of the seismic study was to verify, if possible, the assumption of aquifer continuity along the survey line. The reflection results reveal monoclinal folding in the upper unconsolidated sediments produced by recent movement on bedrock faults. The seismic study confirms that the aquifers are continuous between the proposed recharge and extraction areas despite structural complexity along the recharge avenue.

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Hamdoon, Alaa N. "Structural Analysis and Morphotectonic Interpretation of Ain Sifni Anticline, Northern Iraq." Iraqi Geological Journal 54, no. 2A (July 31, 2021): 49–59. http://dx.doi.org/10.46717/igj.54.2a.4ms-2021-07-25.

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Ain Sifni anticline is located in northern Iraq within High Folded Zone. It contains some tectonic deformations that need to study to determine the source and mechanism of these deformations concerning the geological setting of the study area. This study includes structural and morphotectonic interpretations for the Ain Sifni anticline, such as the visual & digital interpretation of satellite images and the Digital Elevation Model interpretation. These parameters are used to identify the morphogenic criteria and subsequently, to conclude a morphotectonic aspect of the deformations in the Ain Sifni anticline. Because of the regional tectonic evolution in this area, the structural and morphotectonic analysis of this anticline shows much evidence of morphological changes at the southeastern plunge area of the anticline within the Injana and Mukdadiya formations in comparison to the northwestern plunge area of the anticline. In addition, two recent water gaps have been recognized at the southeastern plunge area, one is confirmed and the other is proposed, and then a wind gap has been recognized in the middle of the anticline. A relation has been established between these morphotectonic features with the lateral propagation of the anticline towards the southeast, due to the regional tectonic deformation. A significant main fault has also been detected as a dextral strike-slip fault perpendicular to the fold axis of the anticline. This fault caused a difference in the vergency of the anticline and deformed the outcrops of formations in the study region.

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Abdelsalam, Mohamed G., Mamdouh M. Abdeen, Hamid M. Dowaidar, Robert J. Stern, and Amr A. Abdelghaffar. "Structural evolution of the Neoproterozoic Western Allaqi–Heiani suture, southeastern Egypt." Precambrian Research 124, no. 1 (June 2003): 87–104. http://dx.doi.org/10.1016/s0301-9268(03)00080-9.

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Gehrels, George E., Jason B. Saleeby, and Henry C. Berg. "Geology of Annette, Gravina, and Duke islands, southeastern Alaska." Canadian Journal of Earth Sciences 24, no. 5 (May 1, 1987): 866–81. http://dx.doi.org/10.1139/e87-086.

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Geologic mapping, U–Pb (zircon) geochronometry, and conodont studies indicate that the major pre-Jurassic assemblages on Annette, Gravina, Duke, and adjacent smaller islands include pre-Middle Ordovician metavolcanic and metasedimentary rocks (Wales metamorphic suite); Cambrian metaplutonic rocks; Ordovician – Early Silurian volcanic (Descon Formation), dioritic, and gabbroic rocks; Silurian trondhjemitic plutons; Early Devonian sedimentary (Karheen Formation) and volcanic rocks; Late Triassic sedimentary and volcanic rocks (Hyd Group); and a large body of Late Triassic pyroxene gabbro.Stratigraphic, structural, and intrusive relations record episodes of regional deformation, metamorphism, and uplift during Middle Cambrian – Early Ordovician time (Wales orogeny) and during middle Silurian – earliest Devonian time (Klakas orogeny). Upper Triassic strata were apparently deposited during a latest Paleozoic(?) – Triassic rifting event.Comparison with the geology of Prince of Wales Island indicates that the Annette and Craig subterranes of the Alexander terrane belong to the same tectonic fragment and that the Clarence Strait fault has ~15 km of right-lateral displacement at this latitude. Our geochronologic data indicate that the pyroxene gabbro on Duke Island is Triassic in age and therefore probably unrelated to nearby Cretaceous(?) zoned ultramafic bodies.

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Jones, Sarah. "Contrasting structural styles during polyphase granitoid intrusion, South Victoria Land, Antarctica." New Zealand Journal of Geology and Geophysics 40, no. 2 (June 1997): 237–51. http://dx.doi.org/10.1080/00288306.1997.9514755.

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Ryan, Karen. "A Late Dorset semi-subterranean structure from the Bell Site (NiNg-2), Ekalluk River, Victoria Island." Études/Inuit/Studies 27, no. 1-2 (July 15, 2005): 91–110. http://dx.doi.org/10.7202/010797ar.

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Abstract This paper presents a detailed description of the architectural elements associated with a Late Dorset semi-subterranean structure at the Bell site (NiNg-2), located on the Ekalluk River, southeastern Victoria Island, Nunavut. The 2002 excavation of the house centred on the recovery of detailed information relating to the architectural tradition of the Late Dorset in this area. The structural remains associated with House 6 suggest it was intended for only a short period of occupation that corresponded with the late fall caribou migration through the area. Probably abandoned during the early winter, House 6 is best interpreted as a "between seasons" structure, comparable to the Thule and historic Inuit qarmat.

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Chun, Fan, Wang Gang, Wang Shifeng, and erchie Wang. "Structural Interpretation of extensional Deformation along the Dali Fault System, Southeastern Margin of the Tibetan Plateau." International Geology Review 48, no. 4 (April 2006): 287–310. http://dx.doi.org/10.2747/0020-6814.48.4.287.

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Kolodyazhny, S. Yu, D. S. Zykov, and M. G. Leonov. "Structural-kinematic parageneses of the basement and cover at the southeastern margin of the Baltic Shield." Geotectonics 41, no. 6 (November 2007): 423–39. http://dx.doi.org/10.1134/s0016852107060015.

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Carrillo, Emilio, Hemin A. Koyi, and Faramarz Nilfouroushan. "Structural significance of an evaporite formation with lateral stratigraphic heterogeneities (Southeastern Pyrenean Basin, NE Spain)." Marine and Petroleum Geology 86 (September 2017): 1310–26. http://dx.doi.org/10.1016/j.marpetgeo.2017.07.024.

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Alarifi, Saad S. "Structural implications of potential field data on Southeastern North America." Journal of Geophysics and Engineering 19, no. 2 (April 1, 2022): 142–56. http://dx.doi.org/10.1093/jge/gxac005.

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Abstract The fault system of Eastern Piedmont could be extensive in the East of the USA. Debates remain regarding the sutures zone, contacts and faults between terranes, especially underneath the coastal sediment. However, in this study, a new interpretation of the structures and contacts of the southeastern margin was based on regional land gravity anomaly and magnetic anomaly maps. To delineate and investigate the subsurface geological structures in the southern Appalachian belt and underneath the coastal sediment that covers the southeastern half of the study area, the gravity and magnetic maps were subjected to several filter techniques. The anomalies maps were enhanced by applying the reduction to pole (RTP), analytical signal (AS), tilt derivative (TDR), horizontal gradient (HG), direction filter and power spectrum techniques. The power spectrum filter was applied to separate the regional-residual anomaly. The results of regional anomaly maps display elongate high amplitude anomalies lie in the south that are related to deep-seated igneous mafic intrusive and basaltic lavas emplacement. The directional filter was used to eliminate the sutural trend of the Jurassic dikes that intruded the study area. The result displays the structural contacts clearly after removing the anomalies of the Jurassic. Finally, the edge detection filters (TDR, HG, AS) from the gravity and magnetic maps helped in mapping the anomaly contact of the subsurface bodies. The apparent structural signature of the interpreted contacts confirmed the presence of these structural features in all edge detection methods.

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Özsayin, Erman, and Kadir Dirik. "The role of oroclinal bending in the structural evolution of the Central Anatolian Plateau: evidence of a regional changeover from shortening to extension." Geologica Carpathica 62, no. 4 (August 1, 2011): 345–59. http://dx.doi.org/10.2478/v10096-011-0026-7.

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The role of oroclinal bending in the structural evolution of the Central Anatolian Plateau: evidence of a regional changeover from shortening to extensionThe NW-SE striking extensional Inönü-Eskişehir Fault System is one of the most important active shear zones in Central Anatolia. This shear zone is comprised of semi-independent fault segments that constitute an integral array of crustal-scale faults that transverse the interior of the Anatolian plateau region. The WNW striking Eskişehir Fault Zone constitutes the western to central part of the system. Toward the southeast, this system splays into three fault zones. The NW striking Ilıca Fault Zone defines the northern branch of this splay. The middle and southern branches are the Yeniceoba and Cihanbeyli Fault Zones, which also constitute the western boundary of the tectonically active extensional Tuzgölü Basin. The Sultanhanı Fault Zone is the southeastern part of the system and also controls the southewestern margin of the Tuzgölü Basin. Structural observations and kinematic analysis of mesoscale faults in the Yeniceoba and Cihanbeyli Fault Zones clearly indicate a two-stage deformation history and kinematic changeover from contraction to extension. N-S compression was responsible for the development of the dextral Yeniceoba Fault Zone. Activity along this structure was superseded by normal faulting driven by NNE-SSW oriented tension that was accompanied by the reactivation of the Yeniceoba Fault Zone and the formation of the Cihanbeyli Fault Zone. The branching of the Inönü-Eskişehir Fault System into three fault zones (aligned with the apex of the Isparta Angle) and the formation of graben and halfgraben in the southeastern part of this system suggest ongoing asymmetric extension in the Anatolian Plateau. This extension is compatible with a clockwise rotation of the area, which may be associated with the eastern sector of the Isparta Angle, an oroclinal structure in the western central part of the plateau. As the initiation of extension in the central to southeastern part of the Inönü-Eskişehir Fault System has similarities with structures associated with the Isparta Angle, there may be a possible relationship between the active deformation and bending of the orocline and adjacent areas.

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Anani, C. Y., S. Bonsu, D. Kwayisi, and D. K. Asiedu. "Geochemistry and provenance of Neoproterozoic metasedimentary rocks from the Togo structural unit, Southeastern Ghana." Journal of African Earth Sciences 153 (May 2019): 208–18. http://dx.doi.org/10.1016/j.jafrearsci.2019.03.002.

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Reicherter, K. R., and S. Reiss. "The Carboneras Fault Zone (southeastern Spain) revisited with Ground Penetrating Radar – Quaternary structural styles from high-resolution images." Netherlands Journal of Geosciences 80, no. 3-4 (December 2001): 129–38. http://dx.doi.org/10.1017/s0016774600023799.

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AbstractThe Carboneras Fault Zone (CFZ) represents an active set of sinistral strike-slip faults in the Betic Cordilleras of southeastern Spain. It constitutes a major segment of the ‘Trans-Alboran shear zone’ during the Cenozoic, striking NE-SW. The CFZ separates the Cabo de Gata Block (Neogene volcanics) against Neogene basinal sediments and the metamorphic basement of the Alpujarride Complex.Three sites along the CFZ were examined with Ground Penetrating Radar techniques. Radar surveying was complemented by structural studies. Shallow-depth high-resolution imaging of Tyrrhenian beach terraces exhibited both vertical and minor horizontal offsets in the Rambla Morales site in the south. A sinistral strike-slip fault associated with minor thrust faults in a positive flower structure was detected in the middle segment along the La Serrata ridge, sealed by a caliche of late Pleistocene age (> 10 ka). The Playa de Bolmayor section yielded sub-surface evidence for several faults probably related to recent activity of individual fault strands. Our results suggest a distributed tectonic activity of the CFZ during the Late Quaternary.

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Forde, A., and T. H. Bell. "Late structural control of mesothermal vein-hosted gold deposits in central Victoria, Australia: Mineralization mechanisms and exploration potential." Ore Geology Reviews 9, no. 1 (February 1994): 33–59. http://dx.doi.org/10.1016/0169-1368(94)90018-3.

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Carosi, R., C. Frassi, C. Montomoli, and P. C. Pertusati. "Structural evolution of the Tuscan Nappe in the southeastern sector of the Apuan Alps metamorphic dome (Northern Apennines, Italy)." Geological Journal 40, no. 1 (January 2005): 103–19. http://dx.doi.org/10.1002/gj.995.

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Cook, Y. A., and D. Craw. "Neoproterozoic structural slices in the Ross Orogen, Skelton Glacier area, South Victoria Land, Antarctica." New Zealand Journal of Geology and Geophysics 45, no. 1 (March 2002): 133–43. http://dx.doi.org/10.1080/00288306.2002.9514965.

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Favorito, Daniel A., and Eric Seedorff. "Cenozoic structural evolution of the Catalina metamorphic core complex and reassembly of Laramide reverse faults, southeastern Arizona, USA." Geosphere 17, no. 6 (October 12, 2021): 1928–71. http://dx.doi.org/10.1130/ges02313.1.

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Abstract This study investigates the Late Cretaceous through mid-Cenozoic structural evolution of the Catalina core complex and adjacent areas by integrating new geologic mapping, structural analysis, and geochronologic data. Multiple generations of normal faults associated with mid-Cenozoic extensional deformation cut across older reverse faults that formed during the Laramide orogeny. A proposed stepwise, cross-sectional structural reconstruction of mid-Cenozoic extension satisfies surface geologic and reflection seismologic constraints, balances, and indicates that detachment faults played no role in the formation of the core complex and Laramide reverse faults represent major thick-skinned structures. The orientations of the oldest synextensional strata, pre-shortening normal faults, and pre-Cenozoic strata unaffected by Laramide compression indicate that rocks across most of the study area were steeply tilted east since the mid-Cenozoic. Crosscutting relations between faults and synextensional strata reveal that sequential generations of primarily down-to-the-west, mid-Cenozoic normal faults produced the net eastward tilting of ∼60°. Restorations of the balanced cross section demonstrate that Cenozoic normal faults were originally steeply dipping and resulted in an estimated 59 km or 120% extension across the study area. Representative segments of those gently dipping faults are exposed at shallow, intermediate (∼5–10 km), and deep structural levels (∼10–20 km), as distinguished by the nature of deformation in the exhumed footwall, and these segments all restore to high angles, which indicates that they were not listric. Offset on major normal faults does not exceed 11 km, as opposed to tens of kilometers of offset commonly ascribed to “detachment” faults in most interpretations of this and other Cordilleran metamorphic core complexes. Once mid-Cenozoic extension is restored, reverse faults with moderate to steep original dips bound basement-cored uplifts that exhibit significant involvement of basement rocks. Net vertical uplift from all reverse faults is estimated to be 9.4 km, and estimated total shortening was 12 km or 20%. This magnitude of uplift is consistent with the vast exposure of metamorphosed and foliated cover strata in the northeastern and eastern Santa Catalina and Rincon Mountains and with the distribution of subsequently dismembered mid-Cenozoic erosion surfaces along the San Pedro Valley. New and existing geochronologic data constrain the timing of offset on local reverse faults to ca. 75–54 Ma. The thick-skinned style of Laramide shortening in the area is consistent with the structure of surrounding locales. Because detachment faults do not appear to have resulted in the formation of the Catalina core complex, other extensional systems that have been interpreted within the context of detachments may require further structural analyses including identification of crosscutting relations between generations of normal faults and palinspastic reconstructions.

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Hodges, K. V., J. D. Walker, and B. P. Wernicke. "Footwall structural evolution of the Tucki Mountain detachment system, Death Valley region, southeastern California." Geological Society, London, Special Publications 28, no. 1 (1987): 393–408. http://dx.doi.org/10.1144/gsl.sp.1987.028.01.24.

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Inglis, I., and J. Gerard. "The Alwyn North Field, Blocks 3/9a, 3/4a, UK North Sea." Geological Society, London, Memoirs 14, no. 1 (1991): 21–32. http://dx.doi.org/10.1144/gsl.mem.1991.014.01.03.

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AbstractAbstract: Situated in the southeastern part of the East Shetland Basin, the Alwyn North Field produces oil and gas from Brent Group reservoirs and gas and condensate from the Statfjord Formation. The structural style is of tilted and eroded fault blocks dipping to the west and aligned north-south conforming to the principal normal fault trend. NE-SW cross elements further separate the hydrocarbon accumulations. The hydrocarbon columns are restricted to the Tarbert and upper part of the Ness Formation of the Brent Group, in sediments associated with the retreat of the Brent delta. The Statfjord Formation was deposited in an alluvial, fan-delta setting with increasing marine influence towards the top of the formation.

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Shan, Yehua, Guanjun Nie, Yongjing Ni, and Chung-Pai Chang. "Structural analysis of a newly emerged accretionary prism along the Jinlun-Taimali coast, southeastern Taiwan: From subduction to arc-continent collision." Journal of Structural Geology 66 (September 2014): 248–60. http://dx.doi.org/10.1016/j.jsg.2014.06.002.

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McClelland, W. C., G. E. Gehrels, S. D. Samson, and P. J. Patchett. "Structural and geochronologic relations along the western flank of the coast mountains batholith: Stikine river to Cape Fanshaw, central southeastern Alaska." Journal of Structural Geology 14, no. 4 (April 1992): 475–89. http://dx.doi.org/10.1016/0191-8141(92)90107-8.

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Menzel, Christopher M., and Lindsay Smith. "Relationship Between the Levels of Non-structural Carbohydrates, Digging Date, Nursery-growing Environment, and Chilling in Strawberry Transplants in a Subtropical Environment." HortScience 47, no. 4 (April 2012): 459–64. http://dx.doi.org/10.21273/hortsci.47.4.459.

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Experiments were conducted to study the effect of time of digging and nursery-growing environment on the levels of non-structural carbohydrates in ‘Festival’ strawberry transplants (Fragaria ×ananassa) over 2 years in southeastern Queensland, Australia. We were interested in determining whether there was a strong relationship between the potential productivity of this material and reserves in the plants. First, bare-rooted plants were obtained from Stanthorpe in southern Queensland from early March to mid-April/late April. Second, bare-rooted plants were sourced from Stanthorpe (a warm-growing area) or from Toolangi in Victoria (a cool-growing area). In Year 1 of the experiments, the nursery material from the different treatments was grown at Nambour in southeastern Queensland and fruit yield determined. The total weight of non-structural carbohydrates/plant increased as digging was delayed and was higher in the plants from Stanthorpe than the plants from Toolangi. Plants dug on 17 Mar. in Year 1 had higher weights of non-structural carbohydrates [292 mg/plant dry weight (DW)] than plants dug on 3 Mar. (224 mg/plant) and higher early yield to the end of June or to the end of July and higher total yield to mid-October adjusted by the length of the growing season for the different treatments. Plants dug on 1 Apr. (408 mg/plant) or on 13 Apr. (445 mg/plant) had higher reserves than the plants dug on 17 Mar. but lower yields. Only the differences in yields between the plants dug on 3 Mar. and 17 Mar. reflected the differences in carbohydrates. The stock from Stanthorpe had greater reserves (408 mg/plant) than the stock from Toolangi (306 mg/plant) but similar yields in Year 1 possibly because of poorer flowering in the nursery plants. It was concluded that carbohydrate reserves in transplants only partially reflect their productivity in this environment.

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Smith, Moira T., and George E. Gehrels. "Structural geology of the Lardeau Group near Trout Lake, British Columbia: implications for the structural evolution of the Kootenay Arc." Canadian Journal of Earth Sciences 29, no. 6 (June 1, 1992): 1305–19. http://dx.doi.org/10.1139/e92-104.

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The Lardeau Group is a heterogeneous assemblage of lower Paleozoic eugeoclinal strata present in the Kootenay Arc in southeastern British Columbia. It is in fault contact with lower Paleozoic miogeoclinal strata for all or some of its length along a structure termed the Lardeau shear zone. The Lardeau Group was deformed prior to mid-Mississippian time, as manifested by layer-parallel faults, folds, and evidence for early greenschist-facies metamorphism. Regional constraints indicate probable Devono-Mississippian timing of orogeny, and possible juxtaposition of the Lardeau Group over miogeoclinal strata along the Lardeau shear zone at this time. Further ductile deformation during the Middle Jurassic Columbian orogeny produced large folds with subhorizontal axes, northwest-striking foliation and faults, and orogen-parallel stretching lineations. This deformation was apparently not everywhere synchronous, and may have continued through Late Jurassic time northeast of Trout Lake. This was followed by Cretaceous(?) dextral strike-slip and normal movement on the Lardeau shear zone and other parallel faults. While apparently the locus of several episodes of faulting, the Lardeau shear zone does not record the accretion of far-travelled tectonic fragments, as sedimentological evidence ties the Lardeau Group and other outboard units to the craton.

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30

Wilson, Christopher J. L., David H. Moore, Stefan A. Vollgger, and Harry E. Madeley. "Structural evolution of the orogenic gold deposits in central Victoria, Australia: The role of regional stress change and the tectonic regime." Ore Geology Reviews 120 (May 2020): 103390. http://dx.doi.org/10.1016/j.oregeorev.2020.103390.

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31

Fagan, M. E., D. C. Morton, B. D. Cook, J. Masek, F. Zhao, R. F. Nelson, and C. Huang. "Mapping pine plantations in the southeastern U.S. using structural, spectral, and temporal remote sensing data." Remote Sensing of Environment 216 (October 2018): 415–26. http://dx.doi.org/10.1016/j.rse.2018.07.007.

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32

Box, Stephen E., Susan M. Karl, James V. Jones, Dwight C. Bradley, Peter J. Haeussler, and Paul B. O’Sullivan. "Detrital zircon geochronology along a structural transect across the Kahiltna assemblage in the western Alaska Range: Implications for emplacement of the Alexander-Wrangellia-Peninsular terrane against North America." Geosphere 15, no. 6 (October 16, 2019): 1774–808. http://dx.doi.org/10.1130/ges02060.1.

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Abstract The Kahiltna assemblage in the western Alaska Range consists of deformed Upper Jurassic and Cretaceous clastic strata that lie between the Alexander-Wrangellia-Peninsular terrane to the south and the Farewell and other pericratonic terranes to the north. Differences in detrital zircon populations and sandstone petrography allow geographic separation of the strata into two different successions, each consisting of multiple units, or petrofacies, with distinct provenance and lithologic characteristics. The northwestern succession was largely derived from older, inboard pericratonic terranes and correlates along strike to the southwest with the Kuskokwim Group. The southeastern succession is characterized by volcanic and plutonic rock detritus derived from Late Jurassic igneous rocks of the Alexander-Wrangellia-Peninsular terrane and mid- to Late Cretaceous arc-related igneous rocks and is part of a longer belt to the southwest and northeast, here named the Koksetna-Clearwater belt. The two successions remained separate depositional systems until the Late Cretaceous, when the northwestern succession overlapped the southeastern succession at ca. 81 Ma. They were deformed together ca. 80 Ma by southeast-verging fold-and-thrust–style deformation interpreted to represent final accretion of the Alexander-Wrangellia-Peninsular terrane along the southern Alaska margin. We interpret the tectonic evolution of the Kahiltna successions as a progression from forearc sedimentation and accretion in a south-facing continental magmatic arc to arrival and partial underthrusting of the back-arc flank of an active, south-facing island-arc system (Alexander-Wrangellia-Peninsular terrane). A modern analogue is the ongoing collision and partial underthrusting of the Izu-Bonin-Marianas island arc beneath the Japan Trench–Nankai Trough on the east side of central Japan.

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33

Sapyanik, V. V., E. Yu Lapteva, E. V. Lyubutina, A. I. Nedospasov, P. I. Novikov, N. V. Petrova, A. V. Fateev, and A. P. Khilko. "GEODYNAMICS OF THE SEDIMENTARY COVER AND OIL-AND-GAS PROSPECTS OF THE TOMSK REGION EASTERN TERRITORY." Geology and mineral resources of Siberia, no. 3 (2021): 21–30. http://dx.doi.org/10.20403/2078-0575-2021-3-21-30.

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The article deals with geodynamic processes of the plicative tectonics of the Mesozoic-Cenozoic development stage in the southeastern territory of the West Siberian hemisyneclise, which allowed scientists to significantly clarify the configuration of multi-ordinal structures, to identify the second-order negative structure in the territory of the Baraba-Pikhtovka monocline, and to offer a new view of the structural-tectonic zoning of the Tomsk region eastern territory sedimentary cover. To substantiate the prospects of Jurassic petroleum plays, their resource potential is estimated using the basin modeling method. Based on an integrated analysis of structural imagings, history of the territory tectonic development, calculated maps of effective capacities, test results and WL conclusions, 42 traps of structural, structural-lithological, structural-stratigraphic types were mapped and their assessment by the volume-statistic method by Dl category [inferred resources] was given. The results obtained significantly expand the prospects for peripheral territories of the West Siberian Plate, where it is necessary to complete regional geological exploration.

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Chen, Xiaoyu, Junlai Liu, Jean-Pierre Burg, Yuan Tang, Wenbin Wu, and Jiaxin Yan. "Structural evolution and exhumation of the Yulong dome: Constraints on middle crustal flow in southeastern Tibetan Plateau in response to the India-Eurasia collision." Journal of Structural Geology 137 (August 2020): 104070. http://dx.doi.org/10.1016/j.jsg.2020.104070.

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35

Xin, D., T. N. Yang, M. J. Liang, C. D. Xue, X. Han, C. Liao, and J. Tang. "Syn-subduction crustal shortening produced a magmatic flare-up in middle Sanjiang orogenic belt, southeastern Tibet Plateau: Evidence from geochronology, geochemistry, and structural geology." Gondwana Research 62 (October 2018): 93–111. http://dx.doi.org/10.1016/j.gr.2018.03.009.

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36

Han, Runsheng, Tao Ren, Wenchang Li, Jianguo Huang, Lei Wang, Rensheng Huang, and Yong Yuan. "Discovery of the large-scale Huangtian scheelite deposit and implications for the structural control of tungsten mineralization in southeastern Yunnan, south China." Ore Geology Reviews 121 (June 2020): 103480. http://dx.doi.org/10.1016/j.oregeorev.2020.103480.

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37

Innocent, Arinze J., Emedo O. Chidubem, and Ngwaka A. Chibuzor. "Analysis of aeromagnetic anomalies and structural lineaments for mineral and hydrocarbon exploration in Ikom and its environs southeastern Nigeria." Journal of African Earth Sciences 151 (March 2019): 274–85. http://dx.doi.org/10.1016/j.jafrearsci.2018.12.011.

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Medhat, N. I., M. Atya, E. A. Ragab, A. A. El-Kenawy, M. Abdel Zaher, and J. K. Pringle. "Geophysical site assessment of an active urban development site, southeastern suburb of Cairo, Egypt." Quarterly Journal of Engineering Geology and Hydrogeology 54, no. 1 (May 29, 2020): qjegh2018–151. http://dx.doi.org/10.1144/qjegh2018-151.

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There has been significant structural damage of newly built residential buildings in Quarter-27 District in the SE of Cairo, Egypt. A nearby active limestone quarry may also be affecting ground stability. This paper shows how a near-surface geophysical survey could characterize the site, unusually after the initial housing construction had already been undertaken. Geophysical surveys included seismic refraction (acquired between phases of quarry blasting), electrical resistivity and ground penetrating radar (GPR) 1D and 2D datasets. Geophysical results produced maps of a 3D ground model that also included water table depth, known major faults and a saturated layer that may have caused the building damage. Of the geophysical techniques trialled electrical resistivity tomography and GPR data were deemed optimal. This study shows that it is possible to undertake geophysical surveys to characterize a restricted urban site development.

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39

Utama, Hari Wiki. "STRUKTUR GEOLOGI DAN VULKANOSTRATIGRAFI; PENDEKATAN MODEL ELEVASI DIGITAL DAN CITRA LANDSAT 8." Jurnal Geofisika Eksplorasi 6, no. 2 (July 16, 2020): 156–68. http://dx.doi.org/10.23960/jge.v6i2.80.

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Morphological change and deformation have been happen on natural landscape on volcanic complex. Their would been seen topography formation the give contour line expression, drainage pattern as especially character for understanding geological guideline such as structural geology and lithology. In the geological and geophysics on volcanic complex can use early methode with Digital Elevation Model (DEM) of research scale map and Landsat Image 8 for understanding structural geology and volcanostratigraphy. Research study on Arjuno Welirang Volcanic Complex, East Java, a part of active volcano in Indonesia. This study used scale map 1:25.000 wich analyzed of topography contour and drainage pattern for determination of geological feature as structural geology and volcanostratigraphy unit. Coherence of dense contour line is an igneous rock lava indicated, whereas distantly space contour line is an indicated of pyroclastic. DEM is a product extraction processes of contour topography. MED dan Citra Landsat 8 could help deliniaton of structural geology and volcanostratigraphy unit, which analyzed of morphology, drainage pattern, source of eruption, morphogenesis, and lithology remark. Based on both of image model on KGAW have dextral fault with oriented of northwestern-southeastern, sinistral fault with oriented of southwestern-northeastern, and then structural volcanic as caldera, crater, and debris avalanche. In the KGAW have five source of main eruption and the the other eruption surrounding of KGAW and their become is composed of volcanostratigraphy unit. Approach to using of DEM and Lendsat Image 8 are a part of early stage on for understanding structural geology and volcanostratigraphy on volcanic complex.

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40

Andersen, AN. "Diversity, Seasonality and Community Organization of Ants at Adjacent Heath and Woodland Sites in Southeastern Australia." Australian Journal of Zoology 34, no. 1 (1986): 53. http://dx.doi.org/10.1071/zo9860053.

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Adjacent heath and woodland sites at Wilsons Promontory in Victoria support at least 50 species of ants, with the most abundant being Rhytidoponera victoriae, Iridomyrmex spp. (nitidiceps group), Notoncus hickmani, Aphaenogaster longiceps, Camponotus ?intrepidus and Plagiolepis sp. Total numbers of individuals and species in the woodland were twice that in the heath; this was probably caused by the greater structural complexity of vegetation there, which increased the availability of nesting and foraging sites, the level of insolation of the ground, and possibly also food supply. Total ant activity followed seasonal cycles which correlated with changes in temperature and probably also food supply, and, within these constraints, was regulated by prevailing weather conditions. Individual species displayed distinctive foraging schedules which possibly play an important role in species coexistence. Community organization is analysed according to a scheme derived from studies of ants in arid Australia, where taxa are classified according to their physical requirements and their relationships with dominant species. Although the major species in the present study were separated by differences in body size, food type, and time of foraging, interspecific competition appears to be less important than it is in arid regions. At both sites, opportunistic species (Rhytidoponera) predominated, cryptic species (those associated with soil and litter, such as Plagiolepis sp. and Solenopsis sp.) were abundant, and Iridomyrmex appeared to have a relatively weak influence on the abundance of other ants. This contrasts with the situation in arid regions, where species of Iridomyrmex are extremely important, and opportunistic and cryptic species are often rare or absent.

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41

Capponi, Giovanni, Laura Crispini, and Marco Meccheri. "The metaconglomerates of the eastern Lanterman Range (northern Victoria Land, Antarctica): new constraints for their interpretation." Antarctic Science 11, no. 2 (June 1999): 217–27. http://dx.doi.org/10.1017/s0954102099000280.

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Highly deformed metaconglomerates, mafic to felsic in composition, characterize the eastern Lanterman Range (northern Victoria Land, Antarctica). In the literature the mafic and felsic metaconglomerates are known as Husky Conglomerate and Lanterman Conglomerate respectively. They occur in a 25 km long strip along the Lanterman Fault, which is a major tectonic boundary between the Wilson and the Bowers terranes. New field observations show that there is a gradual transition from mafic to felsic metaconglomerates: this supports a stratigraphical continuum from Husky to Lanterman Conglomerate, and indicates that they belong to the same sedimentary succession. Structural analysis indicates that Husky and Lanterman conglomerates suffered the same structural evolution. From all these evidences, there is no reason to distinguish two types of metaconglomerates, apart from the diversity in the lithological features. However the two terms “Husky Conglomerate” and “Lanterman Conglomerate” can be still used to refer to the mafic and felsic facies of the same sedimentary succession. On the basis of their lithology the Husky Conglomerate can be derived from the Glasgow volcanic arc, whereas the felsic clasts of the Lanterman Conglomerate may be derived from a continental basement below the Glasgow arc or from a continental block bounding the Bowers trough.

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42

Zaika, V. A., and A. A. Sorokin. "Age and Sources of Metasedimentary Rocks of the Galam Terrane in the Mongol–Okhotsk Fold Belt: Results of U–Pb Age and Lu–Hf Isotope Data from Detrital Zircons." Geotectonics 55, no. 6 (November 2021): 779–94. http://dx.doi.org/10.1134/s001685212106008x.

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Abstract The Mongol–Okhotsk fold belt is one of the major structural elements of East Asia. In this article, we present U–Pb age and Hf isotope data for detrital zircons from metasedimentary rocks of the Galam Terrane. Our new data confirm that these rocks contain a significant amount of Archean and Paleoproterozoic zircons: most grains, regardless of age, have negative εHf(t) values from –30.0 to –10.0 and model age tHf(C) > 2.2 Ga. The main sources of detrital material for the metasedimentary rocks of the Galam Terrane were igneous and metamorphic complexes of the southeastern margin of the Siberian Craton. Some of the Devonian and Carboniferous zircons have slightly negative and positive εHf(t) values of ‒7.4 to +6.9 and younger tHf(C) ages of 1.46–0.90 Ga. These zircons were derived from eroded island arcs in the Mongol–Okhotsk Paleocean. Our results suggest that the Galam Terrane is a Paleozoic accretionary complex of the Siberian Craton.

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Wilkins, Colin, and Mike Quayle. "Structural Control of High-Grade Gold Shoots at the Reward Mine, Hill End, New South Wales, Australia." Economic Geology 116, no. 4 (June 1, 2021): 909–35. http://dx.doi.org/10.5382/econgeo.4807.

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Abstract The Reward mine at Hill End hosts structurally controlled orogenic gold mineralization in moderately S plunging, high-grade gold shoots located at the intersection between a late, steeply W dipping reverse fault zone and E-dipping, bedding-parallel, laminated quartz veins (the Paxton’s vein system). The mineralized bedding-parallel veins are contained within the middle Silurian to Middle Devonian age, turbidite-dominated Hill End trough forming part of the Lachlan orogen in New South Wales. The Hill End trough was deformed in the Middle Devonian (Tabberabberan orogeny), forming tight, N-S–trending, macroscopic D2 folds (Hill End anticline) with S2 slaty cleavage and associated bedding-parallel veins. Structural analysis indicates that the D2 flexural-slip folding mechanism formed bedding-parallel movement zones that contained flexural-slip duplexes, bedding-parallel veins, and saddle reefs in the fold hinges. Bedding-parallel veins are concentrated in weak, narrow shale beds between competent sandstones with dip angles up to 70° indicating that the flexural slip along bedding occurred on unfavorably oriented planes until fold lockup. Gold was precipitated during folding, with fluid-flow concentrated along bedding, as fold limbs rotated, and hosted by bedding-parallel veins and associated structures. However, the gold is sporadically developed, often with subeconomic grades, and is associated with quartz, muscovite, chlorite, carbonates, pyrrhotite, and pyrite. East-west shortening of the Hill End trough resumed during the Late Devonian to early Carboniferous (Kanimblan orogeny), producing a series of steeply W dipping reverse faults that crosscut the eastern limb of the Hill End anticline. Where W-dipping reverse faults intersected major E-dipping bedding-parallel veins, gold (now associated with galena and sphalerite) was precipitated in a network of brittle fractures contained within the veins, forming moderately S plunging, high-grade gold shoots. Only where major bedding-parallel veins were intersected, displaced, and fractured by late W-dipping reverse faults is there a potential for localization of high-grade gold shoots (>10 g/t). A revised structural history for the Hill End area not only explains the location of gold shoots in the Reward mine but allows previous geochemical, dating, and isotope studies to be better understood, with the discordant W-dipping reverse faults likely acting as feeder structures introducing gold-bearing fluids sourced within deeply buried Ordovician volcanic units below the Hill End trough. A comparison is made between gold mineralization, structural style, and timing at Hill End in the eastern Lachlan orogen with the gold deposits of Victoria, in the western Lachlan orogen. Structural styles are similar where gold mineralization is formed during folding and reverse faulting during periods of regional east-west shortening. However, at Hill End, flexural-slip folding-related weakly mineralized bedding-parallel veins are reactivated to a lesser degree once folds lock up (cf. the Bendigo zone deposits in Victoria) due to the earlier effects of fold-related flattening and boudinage. The second stage of gold mineralization was formed by an array of crosscutting, steeply W dipping reverse faults fracturing preexisting bedding-parallel veins that developed high-grade gold shoots. Deformation and gold mineralization in the western Lachlan orogen started in the Late Ordovician to middle Silurian Benambran orogeny and continued with more deposits forming in the Bindian (Early Devonian) and Tabberabberan (late Early-Middle Devonian) orogenies. This differs from the Hill End trough in the eastern Lachlan orogen, where deformation and mineralization started in the Tabberabberan orogeny and culminated with the formation of high-grade gold shoots at Hill End during renewed compression in the early Carboniferous Kanimblan orogeny.

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Silva, Fernando Fernandes da, Davis Carvalho de Oliveira, Roberto Dall’Agnol, Luciano Ribeiro da Silva, and Ingrid Viana da Cunha. "Lithological and structural controls on the emplacement of a Neoarchean plutonic complex in the Carajás province, southeastern Amazonian craton (Brazil)." Journal of South American Earth Sciences 102 (October 2020): 102696. http://dx.doi.org/10.1016/j.jsames.2020.102696.

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45

Chen, Hong, Jianmin Hu, Gang Jin, Michael L. Wells, Xingke Yang, Honghui Wang, and Guodong Bao. "Quaternary deformation at the southeastern margin of the Ordos Block, North China: Inferred from structural analysis of basin-bounding faults." Journal of Asian Earth Sciences 197 (August 2020): 104388. http://dx.doi.org/10.1016/j.jseaes.2020.104388.

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46

HOLDSWORTH, R. E., E. TAVARNELLI, and P. CLEGG. "The nature and regional significance of structures in the Gala Group of the Southern Uplands terrane, Berwickshire coast, southeastern Scotland." Geological Magazine 139, no. 6 (November 2002): 707–17. http://dx.doi.org/10.1017/s0016756802006854.

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Structures deforming Llandovery turbidites of the Gala Group in the Southern Uplands terrane are spectacularly exposed in the Berwickshire coastal section, southeastern Scotland. The upward-facing, upright to NW-vergent folds and associated structures appear to record a single regional phase of subhorizontal NW–SE contractional deformation, with a steeply dipping direction of bulk finite extension. These structures are markedly different from those developed in rocks correlated with the Upper Llandovery Hawick Group exposed some 5 km to the south in the Eyemouth–Burnmouth coastal section. Here a highly domainal system of sinistral transpressional strain occurs, with zones of steeply plunging curvilinear folds, clockwise cleavage transection and bedding-parallel sinistral detachment faults. The markedly different bulk strain patterns in the Berwickshire coastal sections are thought to reflect the regionally diachronous nature of transpressional deformation in the Southern Uplands terrane. There are striking similarities in the structures recognized in the Berwickshire coastal sections and those developed in stratigraphically equivalent units along strike in southwestern Scotland and Northern Ireland. This confirms the lateral structural continuity and correlation of tracts and tract boundaries along the entire length of the Southern Uplands terrane. The regional structure suggests that a phase of top-to-the-NW backthrusting and backfolding associated with the southern margin of the Gala Group outcrop marks the transition from orthogonal contraction to sinistral transpression in the Southern Upland thrust wedge during late Llandovery times.

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47

Lindenmayer, David B., and Jeff T. Wood. "Long-term patterns in the decay, collapse, and abundance of trees with hollows in the mountain ash (Eucalyptus regnans) forests of Victoria, southeastern Australia." Canadian Journal of Forest Research 40, no. 1 (January 2010): 48–54. http://dx.doi.org/10.1139/x09-185.

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Large trees with hollows are an important component of stand structural complexity worldwide. Understanding their population dynamics is needed to manage cavity-dependent biota. We quantified long-term rates of collapse of 302 measured trees with hollows in 1939-aged regrowth mountain ash ( Eucalyptus regnans F. Muell.) forest in southeastern Australia. We identified time-dependent dynamics in which the collapse rates of trees slowed from ∼4% annually between 1983 and 1993 to ∼2.2% between 1993 and 2007. Transitions of trees between different decay states (forms) also slowed over time. Nevertheless, during the 24-year period of our study, over half of our marked and measured trees had fallen, but there was no recruitment of new trees with hollows. Under current projections, few trees with hollows will occur on our field sites by ∼2050, although more had been forecast in earlier investigations. Such a paucity of trees with hollows in extensive areas of regrowth mountain ash forests will lead to a shortage of nesting and sheltering sites for cavity-dependent biota. We suggest a short–medium (10- to 100-year) focus on the conservation of old growth and multi-aged stands will be needed to maintain populations of those species strongly associated with trees with hollows in mountain ash forests.

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48

Thannoun, Rayan Gh, Hadeer Gh M. Adeeb, and Azealdeen S. Al-Jawadi. "Extractions Morphotectonic Features Using Satellite Data Processing and DEM-Derived Spatial Models." Iraqi Geological Journal 55, no. 1A (January 31, 2022): 88–107. http://dx.doi.org/10.46717/igj.55.1a.7ms-2022-01-26.

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Morphotectonic features were investigated in the Shireen anticline, which is located in the Kurdistan region of northern Iraq to get more insight into the effect of the tectonic activity on this anticline. For deducing and illustrating the morphotectonic features of the anticline, some digital processing methods have been applied to the part of the image of Landsat in which this anticline appears, and using the Digital Elevation Model. The results explained the identification of such morphotectonic features such as faults, joints, and flat irons topography, and then updated the structural style of the anticline by identifying and drawing the inferred morphotectonic features. The tectonic activity was evaluated in terms of applying longitudinal profiles analysis to some selected valleys in both limbs of the anticline. Consequently, the prominence of knick points in the bottoms of the selected valleys reflects the existence of sudden slopes. Therefore, the southwestern limb of the anticline was suffered more tectonic uplifting activity, and this is clear from the appearance of the triangular shapes in the central part of this limb towards the southeastern plunge of the anticline.

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Clark, W. D., and J. E. Mason. "Base isolation of an existing 10-storey building to enhance earthquake resistance." Bulletin of the New Zealand Society for Earthquake Engineering 38, no. 1 (March 31, 2005): 33–40. http://dx.doi.org/10.5459/bnzsee.38.1.33-40.

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The Rankine Brown Building at Victoria University of Wellington, New Zealand houses the University Library and is pivotal to the operation of the University. Built in the early 1960s, the building was of innovative form and construction for its time, with long span precast concrete waffle slabs over 10 floors supported on 16 main columns. Three years ago a review of the building structure suggested that increased protection of the building would be required to meet the University's expectation for operational continuity after a moderate or major earthquake event in the Wellington area. This paper outlines: Probable areas of structural yielding in a major earthquake event. Structural analysis for base isolation using earthquake time history records. Details of base isolation bearings. Installation of the base isolation bearings. Other structural details that allow movement of the superstructure to take place due to base isolation.

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Raeside, Rob, and Amy Tizzard. "Basement-cover relations in the southeastern Cape Breton Highlands, Nova Scotia, Canada." Atlantic Geology 51, no. 1 (September 7, 2015): 298. http://dx.doi.org/10.4138/atlgeol.2015.013.

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In the southeastern Cape Breton Highlands Neoproterozoic plutonic and metamorphic rocks outcrop in upland areas whereas Carboniferous sedimentary rocks are found in the river valleys and coastal lowlands. Detailed analysis of the contacts between these two groups of rocks including mapping, geometric constructions of the contact relations, structural geological investigations, petrographic analysis and geophysical map interpretations show that the basement rocks were emplaced by a thrust fault that extends at least from the Baddeck River valley to North River, and possibly includes klippen south and east of the highlands. The thrust fault transported a slab of rock with minimum thickness of 200 m a distance of at least 8 km over Horton and Windsor group rocks. East-directed translation of the thrust block likely occurred during the Alleghanian orogeny, and appears to mirror movement previously identified in the northern and western Cape Breton Highlands, implying that much of the upland geology is allochthonous, but likely rooted in the central highlands as positive flower structure.

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Journal articles on the topic 'Geology, Structural Victoria, Southeastern'

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