Tectonic setting and syndepositional deformation of molasse and other nonmarine-paralic sedimentary basins

1978 ◽  
Vol 15 (10) ◽  
pp. 1613-1632 ◽  
Author(s):  
Andrew D. Miall
Keyword(s):  
Tectonic Setting ◽  
Foreland Basin ◽  
Source Area ◽  
Sedimentary Basins ◽  
Sedimentary Facies ◽  
Normal Faults ◽  
Fold Belt ◽  
Active Deformation ◽  
Shallow Marine ◽  
Differential Movement

Molasse is a distinctive sedimentary facies consisting of alluvial and shallow marine deposits derived from source areas undergoing rapid uplift and erosion. The characteristic setting of molasse is within or adjacent to fold belts, and most molasse basins can be classified as foreland basin (external) or intermontane (internal) in type. Thick alluvial and shallow marine sequences in cratonic settings (e.g., taphrogenic troughs) have been classified as molasse by some workers, but this is not generally accepted.Most molasse is synorogenic, and the interdependence of sedimentation and tectonism results in structural and stratigraphic complexity. Intermontane basins generally are tensional in origin and are bounded by high angle (commonly normal) faults. Facies distributions adjacent to each fault depend on relative rates of differential movement, erosion, and sedimentation; accelerated source area uplift causes segmentation and progradation of alluvial fans and generates coarsening-upward sedimentary cycles. Complications are introduced if tectonism occurs in discrete pulses and if basins enlarge themselves along systems of stepped faults.Basins of compressional origin, such as those in a foreland setting, show a greater variety of internal complexity. Facies belts and trends of maximum thickness move progressively out from the core of the fold belt in response to a migration of the zone of active deformation. Conversely, broad structural warps may develop in response to a locally increased sedimentary load, such as a major delta. Folds or thrust faults growing within the basin cause local thinning or unconformable relationships, and may breach the surface so as to isolate parts of the alluvial plain as a synorogenic intermontane basin. Uplift of the fold belt may be discontinuous, causing the generation of stacked sedimentary megacycles. Basin margins commonly are characterized by intraformational angular unconformities and syndepositional folds.Rates of alluvial sedimentation and tectonic movement measured in modern environments are one to two orders of magnitude higher than rates deduced from ancient nonmarine sequences. This lends support to the idea that much sedimentation may be very episodic in nature, but it could also imply that alluvial sequences are deposited much more rapidly than current interpretations of the ancient record would imply, based as they are on relatively crude dating techniques. Only in some wrench-fault basins do calculated sedimentation rates compare with those measured in modern environments.

scholarly journals Multi-Scale Depositional Successions in Tectonic Settings

2020 ◽  
Author(s):  
Liviu Matenco ◽  
Bilal Haq
Keyword(s):  
Spatial Scales ◽  
Source Area ◽  
Sedimentary Basins ◽  
Sedimentary Facies ◽  
Sediment Supply ◽  
Spatial And Temporal Scales ◽  
Multi Scale ◽  
Base Level ◽  
History Of ◽  
Tectonic Settings

<p><span>Observations in sedimentary basins affected by deformation show that the fault-induced depositional accommodation, at various spatial and temporal scales, is closely linked to basin kinematics. The tectonically-driven sediment infill displays the history of deepening and shoaling facies that are controlled by the activation of faults and changes in their offset rates. Simply stated, this results in shifting sedimentary facies towards the source area or towards the basin centre in response to increasing or decreasing depositional space. We propose a first-principle conceptual model for tectonic successions, controlled by the balance between the rates of creation of depositional space and sediment supply. These sediment bodies are bounded by succession boundaries and comprise sourceward or basinward</span> <span>shifting facies tracts</span><span> that are separated at a point of reversal. Due to the relatively steep slopes associated with the evolution of faults, changes in sediment supply rates and mass-wasting are common in these systems and may complicate the normal rhythm of the shifting facies tracts. Once tectonic quiescence is achieved, and if the basin is connected to the open ocean, eurybatic or eustatic base level changes may take over and play a greater role in sedimentary rhythm and cyclicity. We illustrate the efficacy of the new concept with a review of examples from extensional, contractional and strike-slip basins. We show that the basic tectonic succession model is applicable at all temporal and spatial scales and whether the tectonics cause subsidence or uplift, and in all types of tectonic settings that determine the evolution of sedimentary basins.</span></p>

Stratigraphic and Structural setting of Cenozoic deep-sea units from the Agri valley (southern Apennines, Italy), recording the tectonic evolution of the Southern Apennines.

2021 ◽  
Author(s):  
Giacomo Prosser ◽  
Giuseppe Palladino
Keyword(s):  
Deep Sea ◽  
Field Survey ◽  
Tectonic Setting ◽  
Mediterranean Area ◽  
Normal Faults ◽  
Accretionary Wedge ◽  
Fold Belt ◽  
Southern Apennines ◽  
Structural Setting ◽  
Tethys Ocean

<p>Cenozoic units from thrust-top and foredeep basins provide crucial information for constraining the progressive evolution of the Southern Apennine thrust and fold belt and, more in general, the geodynamic evolution of the Mediterranean area. For this reason, we have analysed the stratigraphic and tectonic setting of deep-sea Cenozoic units exposed in the southeastern sector of the Agri Valley (Basilicata, Southern Italy), in an area located immediately north of the Montemurro village, between the Costa Molina and Monte dell’Agresto localities. These units have not been studied in detail so far and different interpretations are reported in the literature. The study was based on an accurate field survey which led to a new geological map and to the reconstruction of the stratigraphic and structural setting of the area. Results of the field survey were constrained by well, seismic and new biostratigraphic data kindly provided by Eni. In our study, we focussed on the Albidona Formation, which was deposited in a thrust-top basin on the Liguride accretionary wedge, formed above the NW-dipping subduction of the Ligurian Tethys Ocean during the Late Cretaceous? - Early Miocene. Facies characteristics and age determinations allowed the differentiation of the Albidona Formation in two members, with the older one, identified as Member B-C (Lutetian) consisting of alternating marls, sandstones and clays and the younger one, identified as Member D (Barthonian/Priabonian), consisting in alternating sandstones and conglomerates. In particular, the presence of marker horizons such as a pebbly mudstone containing ophiolite debris strongly helped in the structural reconstructions. By this means, we recognized the presence of two folding phases affecting the Albidona Formation. Moreover, the geometrical relationships between the two members and the overlying Miocene Gorgoglione Formation allowed recognising two major NE-trending normal faults, which crosscut the aforementioned structures. These data provide new indications on the tectonic setting and the evolution of the Southern Apennines thrust and fold belt.</p>

On the reactivation of extensional fault systems

1986 ◽  
Vol 317 (1539) ◽  
pp. 179-194 ◽  
Keyword(s):  
Large Fraction ◽  
Tectonic Setting ◽  
Sedimentary Basins ◽  
Shear Zones ◽  
Normal Faults ◽  
Basin Inversion ◽  
Fault Systems ◽  
Detachment Faults ◽  
Southeastern Australia ◽  
Transfer Faults

In terranes that have undergone substantial extension, three sets of faults dominate: ( a ) shallow- to steep-dipping, commonly rotational normal faults; ( b ) a really extensive, shallow-dipping, normal detachment faults; and ( c ) steep-dipping transfer faults that strike at high angles to the normal faults. These fault systems may extend through a large fraction of the crust. Reactivation of these fault systems will depend primarily on the relative strengths of the faults (shear zones) and their host rock, and their orientation in the prevailing stress field. It is concluded that reactivation is generally mechanically favoured, but that it will probably only take place when the fault-shear zones are in near-ideal orientations. Consideration of the tectonic setting of extended terranes and of the limited number of well described examples suggests that reverse (thrust) reactivation of the normal and detachment faults and wrench reactivation of transfer faults are the most likely styles. Examples of these styles are described from the Bass Strait Basins of southeastern Australia. Because extended terranes commonly underlie sedimentary basins (for example, on passive continental margins), reactivation of extensional faults may be a key control on the tectonic evolution of such basins (i.e. basin inversion).

Detrital zircon U-Pb ages of Paleogene deposits in the southwestern Sichuan foreland basin, China: Constraints on basin-mountain evolution along the southeastern margin of the Tibetan Plateau

2019 ◽  
Vol 132 (3-4) ◽  
pp. 668-686 ◽  
Author(s):  
Hanyu Huang ◽  
Dengfa He ◽  
Di Li ◽  
Yingqiang Li
Keyword(s):  
Detrital Zircon ◽  
Sichuan Basin ◽  
Tectonic Setting ◽  
Foreland Basin ◽  
Source Area ◽  
Orogenic Belt ◽  
Sediment Supply ◽  
Scaling Analysis ◽  
The Tibetan Plateau ◽  
The Sichuan Basin

Abstract The tectonic setting of the southwestern Sichuan foreland basin, China, changed rapidly during the Paleogene period, and records from this period may provide crucial information about the formation and tectonic processes that affected the Sichuan Basin. To constrain the provenance and to reconstruct the paleogeography of the Paleogene successions, we conducted a detailed analysis of the petrology, geochronology, and sedimentary facies of rocks from the southwestern Sichuan foreland basin. The detrital components of the three analyzed sandstone samples indicate moderately to highly mature sediment that was primarily derived from a recycled orogen provenance. Five major age populations were identified in the U-Pb age spectra: Neoarchean to Siderian (2524–2469 Ma and 2019–1703 Ma), Neoproterozoic (Tonian to Cryogenian, 946–653 Ma), Ordovician to Carboniferous (Katian to lower Pennsylvanian, 448–321 Ma), and Carboniferous to Triassic (306–201 Ma). Each of these age populations corresponds to one or several potential sources around the southwestern Sichuan foreland basin. A multidimensional scaling analysis indicated that the Paleogene zircons were mainly derived from recycled sediments of the Songpan-Ganzi terrane and the Sichuan Basin, with minor input from the Yidun terrane, Kangdian terrane, Qinling orogenic belt, and Jiangnan-Xuefeng orogenic belt. More specifically, the sediment supply from the Songpan-Ganzi terrane to the foreland basin decreased significantly from the Mingshan stage to the Lushan stage, and the Sichuan Basin simultaneously became the most important source area. In addition, there is a high correlation between the detrital zircon U-Pb age spectrum of the southwestern Sichuan Basin and that of the Xichang Basin, which may suggest that a wider and unified Paleo-Yangtze Basin existed during the Late Cretaceous-early Paleogene.

scholarly journals Neoproterozoic (Torridonian) alluvial fan succession, northwest Scotland, and its tectonic setting and provenance

2001 ◽  
Vol 138 (2) ◽  
pp. 161-184 ◽  
Author(s):  
GEORGE E. WILLIAMS
Keyword(s):  
Tectonic Setting ◽  
Normal Fault ◽  
Source Area ◽  
Alluvial Fan ◽  
Normal Faults ◽  
Main Body ◽  
The West ◽  
The North ◽  
Divergent Flow ◽  
Laurentian Margin

The presence of alluvial fan deposits in the lower Neoproterozoic Torridon Group in northwest Scotland illuminates Torridonian basin development at the eastern Laurentian margin. The 450 m thick Cape Wrath Member of the Applecross Formation consists of alluvial fan conglomerate and arkose succeeded by more distal, braidplain feldspathic sandstone. Palaeocurrent data comprising >2650 measurements on trough cross-bedding are of low variability and show overall eastward flow. The projection upcurrent of regionally divergent flow directions for the lower part of the member indicates a fan of c. 50 km radius with its apex 30 km to the west near a basement (pre-Caledonian) normal fault with downthrow to the east beneath the north Minch Basin. Extensional tectonics controlled deposition of the Applecross Formation. Regional uplift, causing erosion of a youthful topography on the Lewisian Gneiss, was followed by the development of the Applecross extensional basin in two main stages. Uplift of a western source area by movement on basin-bounding normal faults occurred first in the north and caused pediplanation and alluvial fan deposition in the Cape Wrath area, with subsequent uplift of the source area for the main body of the Applecross Formation occurring further to the west and south along the line of the Minch Fault. The bulk of the Applecross Formation was derived from a weathered terrain of felsic crystalline and related supracrustal rocks reaching from the Outer Hebrides region westward for up to c. 250 km onto what are now the continental margins of the North Atlantic. The tectonic events may mark an early phase in the crustal extension that led ultimately to the opening of the Iapetus ocean.

scholarly journals Geochemical evaluation of Campanian-Maastritchian clay-shale sediments of Patti formation, Southern Bida and Mamu Formation, northern Anambra basins

2020 ◽  
Vol 18 ◽  
pp. 97-118
Author(s):  
Nathaniel Odoma Atabo ◽  
Ojochogwu Idakwo Sunday
Keyword(s):  
Source Rock ◽  
Tectonic Setting ◽  
Source Area ◽  
Sedimentary Basins ◽  
Passive Margin ◽  
Clay Shale ◽  
Clay Shales ◽  
Geochemical Evaluation ◽  
Clay Deposits ◽  
Chemical Index

Two basins (Southern Bida and Northern Anambra Basins) were investigated to deduce weathering, paleooxygenation, provenance, depositional environment and tectonic setting, as well as to establish a relationship between the two basins. The obtained high values of calculated weathering indices such as Chemical index of alteration (CIA > 90), Chemical Index of Weathering (CIW > 90), Plagioclase Index of Alteration (PIA > 90) and the Al2O3-(CaO + Na2O)-K2O ternary relationship for the clay – shale sediments from both basins indicate intense weathering in the source area. Important geochemical ratios such as V/Cr, Cu/Zn, Ni/Co, (Cu+Mo)/Zn, revealed predominantly oxic conditions for the clay – shale sediments from both basins, although, a more reducing or an anoxic condition cannot be ruled out for the clay – shale sediments from the Southern Bida basin due to high ratios of U/Th (1.93-5.67) and Cu/Zn (0.19-5.00). In addition, the Sr/Ba ratios (0.16–3.50) for the clay-shales from the Southern Bida basin indicated an alternated marine and continental paleo-depositional settings and only continental setting (Sr/Ba ratios = 0.22 – 0.50) for the Northern Anambra basin. The Th/Sc, La/Sc, Th/Co and the LREE/HREE ratios showed a derivation of the shale and clay deposits from similar felsic-rich source rock while the log of (K2O/Na2O) vs SiO2, revealed a Passive Margin tectonic setting for the two Basins. There is insignificant differences between the geochemical classifications, weathering, source rock/provenance and tectonic settings of clay-shale sediments of both sedimentary basins, however, there exist slight disparity in their salinity conditions and redox settings. Keywords: Geochemistry, Clay-shale, Provenance, Tectonic Setting, Northern Anambra and Southern Bida Basins

Seismic stratigraphy of the East-Siberian and Chukchi seas as a key to the Amerasia Basin stratigraphy end evolution

2020 ◽  
Author(s):  
Kseniia Startseva ◽  
Anatoly Nikishin
Keyword(s):  
Foreland Basin ◽  
Sedimentary Basins ◽  
Geological Structure ◽  
Seismic Survey ◽  
Normal Faults ◽  
Seismic Profiles ◽  
The North ◽  
Sea Bottom ◽  
Reported Study ◽  
Bottom Sampling

<p>Based on new seismic survey, offshore drilling and geological structure of the adjacent onshore a new model of geological evolution of sedimentary basins of the East-Siberian and Chukchi seas since the Mesozoic has been constructed. The main stages of their tectonic history are highlighted: 1) forming of the foreland basin in Jurassic – Early Creatceous time; 2) synrift extension in Aptian-Albian time; 3) start of postrift subsidence in Later Cretaceous; 4) uplift and deformations at the turn of Cretaceous and Paleogene, start of forming of the thick (up to 4-6 km) clinoform complex; 5) episode of synrift extension in Middle-Later Eocene, forming of the system of multiple low-amplitude normal faults; 6) inversion deformations in Oligocene-Miocene; 7) relatively calm tectonic conditions in Neogene-Quaternary time. Boundaries of the interpreted seismic complexes corresponding to these stages has been extended to the entire Amerasia basin with regards to the ages of magnetic anomalies in the Gakkel Ridge and sea-bottom sampling on the Mendeleev Rise. Volcanic areas of the De Long Islands and the North Wrangel High has been traced on the seismic profiles toward Mendeleev Rise and Podvodnikov Basin and dated as ±125 Ma. According to the seismic interpretation, the age of the Podvodnikov and Toll basins is not older than Aptian. The reported study was funded by RFBR and NSFB, project number 18-05-70011, 18-05-00495 and 18-35-00133.</p>

scholarly journals Late Palaeozoic tectonics in Central Mediterranean: a reappraisal

2020 ◽  
Vol 113 (1) ◽  
Author(s):  
Giancarlo Molli ◽  
Andrea Brogi ◽  
Alfredo Caggianelli ◽  
Enrico Capezzuoli ◽  
Domenico Liotta ◽  
...  
Keyword(s):  
Shear Zone ◽  
Tectonic Setting ◽  
Regional Scale ◽  
Sedimentary Basins ◽  
Sedimentary Facies ◽  
Low Grade ◽  
Central Mediterranean ◽  
Deep Well ◽  
Late Palaeozoic ◽  
Splay Faults

AbstractA revision of late Palaeozoic tectonics recorded in Tuscany, Calabria and Corsica is here presented. We propose that, in Tuscany, upper Carboniferous-Permian shallow-marine to continental sedimentary basins, characterized by unconformities and abrupt changes in sedimentary facies, coal-measures, red fanglomerate deposits and felsic magmatism, may be related with a transtensional setting where upper-crustal splay faults are linked with a mid-crustal shear zone. The remnants of the latter can be found in the deep-well logs of Pontremoli and Larderello-Travale in northern and southern Tuscany respectively. In Calabria (Sila, Serre and Aspromonte), a continuous pre-Mesozoic crustal section is exposed, where the lower-crustal portion mainly includes granulites and migmatitic paragneisses, together with subordinate marbles and metabasites. The mid-crustal section, up to 13 km-thick, includes granitoids, tonalitic to granitic in composition, emplaced between 306 and 295 Ma. They were progressively deformed during retrograde extensional shearing, with a final magmatic activity, between 295 ± 1 and 277 ± 1 Ma, when shallower dykes were emplaced in a transtensional regime. The section is completed by an upper crustal portion, mainly formed by a Palaeozoic sedimentary succession deformed as a low-grade fold and thrust belt, and locally overlaying medium-grade paragneiss units. As a whole, these features are reminiscent of the nappe zone domains of the Sardinia Variscan Orogen. In Corsica, besides the well-known effusive and intrusive Permian magmatism of the “Autochthonous” domain, the Alpine Santa Lucia Nappe exposes a kilometer-scale portion of the Permian lower to mid-crust, exhibiting many similarities to the Ivrea Zone. The distinct Mafic and Granitic complexes characterizing this crustal domain are juxtaposed through an oblique-slip shear zone named Santa Lucia Shear Zone. Structural and petrological data witness the interaction between magmatism, metamorphism and retrograde shearing during Permian, in a temperature range of c. 800–400 °C. We frame the outlined paleotectonic domains within a regional-scale, strain–partitioned, tectonic setting controlled by a first-order transcurrent/transtensional fault network that includes a westernmost fault (Santa Lucia Fault) and an easternmost one (East Tuscan Fault), with intervening crustal domains affected by extensional to transtensional deformation. As a whole, our revision allows new suggestions for a better understanding of the tectonic framework and evolution of the Central Mediterranean during the late Palaeozoic.

scholarly journals Exhumation history of the Variscan suture: Constrains on the detrital zircon geochronology from Carboniferous–Permian sandstones (Northern Gemericum; Western Carpathians)

2019 ◽  
Vol 70 (6) ◽  
pp. 512-530
Author(s):  
Anna Vozárová ◽  
Katarína Šarinová ◽  
Dušan Laurinc ◽  
Elena Lepekhina ◽  
Jozef Vozár ◽  
...  
Keyword(s):  
Detrital Zircon ◽  
Tectonic Setting ◽  
Age Distribution ◽  
Foreland Basin ◽  
Sedimentary Basins ◽  
Distribution Patterns ◽  
Magmatic Zircon ◽  
Detrital Zircon Geochronology ◽  
History Of ◽  
Depositional Age

Abstract The Late Paleozoic sedimentary basins in the Northern Gemericum evolved gradually in time and space within the collisional tectonic regime of the Western Carpathian Variscan orogenic belt. The detrital zircon age spectra, obtained from the Mississippian, Pennsylvanian and Permian metasediments, have distinctive age distribution patterns that reflect the tectonic setting of the host sediments. An expressive unimodal zircon distribution, with an age peak at 352 Ma, is shown by the basal Mississippian metasediments. These represent a relic of the convergent trench-slope sedimentary basin fill. In comparison, the Pennsylvanian detrital zircon populations display distinct multimodal distributions, with the main age peaks at 351, 450, 565 Ma and smaller peaks at ~2.0 and ~2.7 Ga. This is consistent with derivation of clastic detritus from the collisional suture into the foreland basin. Similarly, the Permian sedimentary formations exhibit the multimodal distribution of zircon ages, with main peaks at 300, 355 and 475 Ma. The main difference, in comparison with the Pennsylvanian detrital zircon assemblages, is the sporadic occurrence of the Kasimovian– Asselian (306–294 Ma), as well as the Artinskian–Kungurian (280–276 Ma) igneous zircons. The youngest magmatic zircon ages nearly correspond to the syn-sedimentary volcanic activity with the depositional age of the Permian host sediments and clearly indicate the extensional, rift-related setting.

scholarly journals Neoproterozoic (Torridonian) alluvial fan succession, northwest Scotland, and its tectonic setting and provenance

2001 ◽  
Vol 138 (4) ◽  
pp. 471-494 ◽  
Author(s):  
GEORGE E. WILLIAMS
Keyword(s):  
Tectonic Setting ◽  
Normal Fault ◽  
Source Area ◽  
Alluvial Fan ◽  
Normal Faults ◽  
Main Body ◽  
The West ◽  
North West ◽  
The North ◽  
Divergent Flow

The presence of alluvial fan deposits in the lower Neoproterozoic Torridon Group in north-west Scotland illuminates Torridonian basin development at the eastern Laurentian margin. The 450 m thick Cape Wrath Member of the Applecross Formation consists of alluvial fan conglomerate and arkose succeeded by more distal, braidplain feldspathic sandstone. Palaeocurrent data comprising > 2650 measurements on trough cross-bedding are of low variability and show overall eastward flow. The projection upcurrent of regionally divergent flow directions for the lower part of the member indicates a fan of c. 50 km radius with its apex 30 km to the west near a basement (pre-Caledonian) normal fault with downthrow to the east beneath the north Minch Basin. Extensional tectonics controlled deposition of the Applecross Formation. Regional uplift, causing erosion of a youthful topography on the Lewisian Gneiss, was followed by the development of the Applecross extensional basin in two main stages. Uplift of a western source area by movement on basin-bounding normal faults occurred first in the north and caused pediplanation and alluvial fan deposition in the Cape Wrath area, with subsequent uplift of the source area for the main body of the Applecross Formation occurring further to the west and south along the line of the Minch Fault. The bulk of the Applecross Formation was derived from a weathered terrain of felsic crystalline and related supracrustal rocks reaching from the Outer Hebrides region westward for up to c. 250 km onto what are now the continental margins of the North Atlantic. The tectonic events may mark an early phase in the crustal extension that led ultimately to the opening of the Iapetus ocean.

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