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Trace Fossils from Silurian and Devonian Turbidites of the Chauvay Area, Southern Tien Shan, Kyrgyzstan
Annales Societatis Geologorum Poloniae (2009), vol. 79: 1-11. TRACE FOSSILS FROM SILURIAN AND DEVONIAN TURBIDITES OF THE CHAUVAY AREA, SOUTHERN TIEN SHAN, KYRGYZSTAN Michał WARCHO£1 & Stanisław LESZCZYŃSKI2 1 Institute o f Geological Sciences, Polish Academy of Sciences, ul. Senacka 1, 31-002 Kraków, Poland, e-mail: [email protected] Institute o f Geological Sciences, Jagiellonian University, ul. Oleandry 2a, 30-063 Kraków, Poland, e-mail: [email protected] Warchoł, M. & Leszczyński, S., 2009. Trace fossils from Silurian and Devonian turbidites of the Chauvay area, southern Tien Shan, Kyrgyzstan. Annales Societatis Geologorum Poloniae, 79: 1-11. Abstract: The siliciclastic turbidite successions (Pul’gon and Dzhidala Formations) that crop out in the eastern part of the Chauvay River valley, are marked on geological maps as a belt of terrigenous deposits of Silurian- Devonian age. They resemble deposits of overbank areas and deposilional lobes of deep sea fans, and display common trace fos sils particularly on lower surfaces of sandstone beds. Sixleen ichnolaxa representing four morphological groups have been dislinguished. The trace fos sil as semblages suggest their affiliation to the Nereites ichnolacies. Various branched, prelurbidlte forms predominate in both examlned units, although the assemblages of individual units differ slightly in composition. In the Pulg’on Formation, small, densely distributed burrows commonly occur on lower surfaces of sandstone beds. Shallow burrowing depth together with relatively low diversity trace fossil assemblages indicate lowered oxygenation of the sea floor. Key words: Tien Shan; Kyrgyzstan; Silurian-Devonian; turbidites; trace fossils. Manuscript received 12 August 2008, accepted 26 February 2009 INTRODUCTION described from these deposits. -
PROPERTY of Alabita STATE Geoloclcal Survlfl LBWY
PROPERTY OF ALABItA STATE GEOLOClCAL SURVLFl LBWY U.S. DEPARTMENT OF THE INTERIOR TO ACCOMPANY MAP 1-1942 U.S. GEOLOGICAL SURVEY GEOLOGIC MAP AND FOLD- AND THRUST-BELT INTERPRETATION OF THE SOUTHEASTERN PART OF THE CHARLEY RlVER QUADRANGLE, EAST-CENTRAL ALASKA By James H. Dover INTRODUCTION The report contains a geologic map and interpretive cross sections (scale 1:100,000, sheets 1 and 2, respectively), This report presents the geologic map evidence for and a small-scale tectonic map showing regional structural the interpretation of the Charley River region as a fold and continuity and trends (scale 1:500,000, fig. sheet 2). thrust belt. Stratigraphic problems bearing on the rigor of 4, The geologic map contains considerable detail this interpretation are briefly reviewed, and some regional compiled from more than 1,000 field stations (fig. 1, tectonic implications of the fold and thrust belt sheet 1). Nearly 85 percent of these stations and their model-including the interaction of the fold and thrust belt included data are recompiled directly from the original field with the Tintina strike-slip fault zone, are also discussed. notes and field sheets (1960-63, 1967-68, 1973) of PREVIOUS WORK Brabb and Churkin. The new data were collected during parts of four field seasons, from 1982 to 1985, and Geologic observations were first made in the Charley involve a total of 25 days of helicopter-supported field River region by pioneering Alaskan geologists such work, concentrated largely in localities where pre-existing as Prindle (1905, 1906, 1913), Kindle (1908), Brooks data were scarce, or in localities judged from previous and Kindle (1908), and Cairnes (1914), but the recon- work to be critical to structural interpretation. -
Trace Fossils from Lower Palaeozoic Ocean-Floor Sediments of the Southern Uplands of Scotland M
Transactions of the Royal Society of Edinburgh: Earth Sciences, 73, 67-87, 1982 Trace fossils from Lower Palaeozoic ocean-floor sediments of the Southern Uplands of Scotland M. J. Benton ABSTRACT: The Ordovician and Silurian rocks of the Southern Uplands of Scotland have been interpreted as sediments deposited on the northern margin of the Iapetus Ocean. Trace fossils are abundant at many localities in ocean-floor turbidites and mudstones that usually lack all other evidence of life. Twelve ichnogenera are present, and they are mainly meandering locomotion and feeding trails and burrow networks: Dictyodora, Caridolites, Helminthoida, Neonereites, Nereites, Protovirgularia, Gordia, Megagrapton, Paleodictyon, Chondrites, Plano- lites and Skolithos. The trace fossils occur in at least five distinct assemblages and the composition of these was probably controlled by the frequency and nature of the turbidity currents, and possibly by the oxygen content of the mudstones. Where turbidity currents were weak, abundant Dictyodora, together with Caridolites, Neonereites, Nereites, Protovirgularia and Gordia occur in various combinations. Where currents were stronger, traces such as Gordia, Paleodictyon and Megagrapton may be exhumed and cast on turbidite soles, and the sand may contain Skolithos. The 'deep-sea' Nereites trace fossil facies is divisible into several assemblages, presumably environmentally controlled. KEY WORDS: Iapetus Ocean, ichnology, mudstone, Nereites Facies, Ordovician, shale, Silurian, turbidite. Deep-sea trace fossil assemblages of the Ordovician and 1. Geological setting Silurian are poorly known. The Lower Palaeozoic turbidites and associated mudstones of the Southern Uplands of Scot- 1.1. Structure and history of deposition land preserve at least 12 ichnogenera and there are several The Ordovician and Silurian rocks of the Southern Uplands distinct assemblages that are associated with particular (basalts, cherts, graptolitic shales, greywackes and red or sedimentary conditions. -
Redalyc.Depositional Environment of Stelloglyphus Llicoensis Isp. Nov
Andean Geology ISSN: 0718-7092 [email protected] Servicio Nacional de Geología y Minería Chile Le Roux, Jacobus P.; Nielsen, Sven N.; Henríquez, Álvaro Depositional environment of Stelloglyphus llicoensis isp. nov.: a new radial trace fossil from the Neogene Ranquil Formation, south-central Chile Andean Geology, vol. 35, núm. 2, julio, 2008, pp. 307-319 Servicio Nacional de Geología y Minería Santiago, Chile Disponible en: http://www.redalyc.org/articulo.oa?id=173918441006 Cómo citar el artículo Número completo Sistema de Información Científica Más información del artículo Red de Revistas Científicas de América Latina, el Caribe, España y Portugal Página de la revista en redalyc.org Proyecto académico sin fines de lucro, desarrollado bajo la iniciativa de acceso abierto Revista Geológica de Chile 35 (2): 307-319. July, 2008 Revista Geológica de Chile www.scielo.cl/rgch.htm Depositional environment of Stelloglyphus llicoensis isp. nov.: a new radial trace fossil from the Neogene Ranquil Formation, south-central Chile jacobus P. Le Roux1, Sven N. Nielsen2, álvaro Henríquez1 1 Departamento de Geología, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Casilla 13518, Correo 21, Santiago, Chile. [email protected]; [email protected] 2 Institut für Geowissenschaften, Christian-Albrechts-Universität, Ludewig-Meyn-Str.10, 24118 Kiel, Germany. [email protected] ABSTRACT. Stelloglyphus llicoensis isp. nov. is a large radial, discoidal to ellipsoidal trace fossil with a central shaft and single to bifurcating branches radiating from different levels. A 30 m thick measured section of the Ranquil For- mation at Punta Litre contains an associated trace fossil assemblage including Zoophycos, Chondrites, Phycosiphon, Nereites missouriensis, Lockeia siliquaria, Psammichnites(?), Parataenidium, Ophiomorpha, and Rhizocorallium, some of which reworked the Stelloglyphus traces. -
Innovations in Animal-Substrate Interactions Through Geologic Time
The other biodiversity record: Innovations in animal-substrate interactions through geologic time Luis A. Buatois, Dept. of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon SK S7N 5E2, Canada, luis. [email protected]; and M. Gabriela Mángano, Dept. of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon SK S7N 5E2, Canada, [email protected] ABSTRACT 1979; Bambach, 1977; Sepkoski, 1978, 1979, and Droser, 2004; Mángano and Buatois, Tracking biodiversity changes based on 1984, 1997). However, this has been marked 2014; Buatois et al., 2016a), rather than on body fossils through geologic time became by controversies regarding the nature of the whole Phanerozoic. In this study we diversity trajectories and their potential one of the main objectives of paleontology tackle this issue based on a systematic and biases (e.g., Sepkoski et al., 1981; Alroy, in the 1980s. Trace fossils represent an alter- global compilation of trace-fossil data 2010; Crampton et al., 2003; Holland, 2010; native record to evaluate secular changes in in the stratigraphic record. We show that Bush and Bambach, 2015). In these studies, diversity. A quantitative ichnologic analysis, quantitative ichnologic analysis indicates diversity has been invariably assessed based based on a comprehensive and global data that the three main marine evolutionary on body fossils. set, has been undertaken in order to evaluate radiations inferred from body fossils, namely Trace fossils represent an alternative temporal trends in diversity of bioturbation the Cambrian Explosion, Great Ordovician record to assess secular changes in bio- and bioerosion structures. The results of this Biodiversification Event, and Mesozoic diversity. Trace-fossil data were given less study indicate that the three main marine Marine Revolution, are also expressed in the attention and were considered briefly in evolutionary radiations (Cambrian Explo- trace-fossil record. -
New Methods for Ichnofabric Analysis and Correlation with Orbital Cycles Exemplified by the Baden-Sooss Section (Middle Miocene, Vienna Basin)
GEOLOGICA CARPATHICA, OCTOBER 2008, 59, 5, 395-409 New methods for ichnofabric analysis and correlation with orbital cycles exemplified by the Baden-Sooss section (Middle Miocene, Vienna Basin) PETER PERVESLER1, ALFRED UCHMAN2 and JOHANN HOHENEGGER1 'Department of Paleontology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria; [email protected]; [email protected] 2Institute of Geological Sciences, Jagiellonian University, Oleandry 2a, 30-063 Kraków, Poland; [email protected] (Manuscript received December 13, 2007; accepted in revised form June 12, 2008) Abstract: A two step cluster analysis based on log-likelihood measures for categorial variables using ‘Schwarz’s Bayesian Criterion’ for grouping allows the automatic detection of ichnofabric categories from a large data set. Preferred succes sions of these ichnofabrics were tested by ‘Embedded Markov Chains’. This leads to the following ichnofacies interpreta tion: Alternating periods of higher/lower accumulation rates with higher/lower inputs of particulate food and higher/ lower oxygen contents in pore waters led to sequential colonization of the substrate. The trace fossils Phycosiphon and Nereites represent opportunistic colonization of oxygenated sediments rich in particulate organic matter (POM) by de posit-feeding animals, quickly after an increased sediment input. A further stage of colonization caused by the decrease of POM induced by consumption and oxidation forced the animals to search for food on sediment surfaces and from the water column. The open burrows Thalassinoides, Chondrites, Trichichnus and Zoophycos indicate stable-bottom conditions in periods of low accumulation rates. Zoophycos, Phycosiphon, Nereites and Teichichnus suggest the Zoophycos ichnofacies for the lower section of the core; a transition to the distal part of the Cruziana ichnofacies is suggested for the upper section of the core with the appearance of Thalassinoides. -
Late Ordovician-Early Silurian Trace Fossils from the Matapedia Group, Tobique River, Western New Brunswick, Canada
LATE ORDOVICIAN-EARLY SILURIAN TRACE FOSSILS FROM THE MATAPEDIA GROUP, TOBIQUE RIVER, WESTERN NEW BRUNSWICK, CANADA R.K. Pi ekeri 11 Department of Geology, U niversity of New Brunswick Fredericton, New Brunswick, E3B 5A3 L.R. Fyffe Department of Forest, Mines and Energy, Mineral Resources D ivision Fredericton, New Brunswick, E3B 5H1 W.H. Forbes Department of Geology, U niversity of Maine at Presque Isle Maine 04769 Date Received November 1, 1986 Date Accepted February 8, 1987 Late Ordovician-Early Silurian flysch slope deposits of the Matapedia Group of the Matapedia Basin on the lobique River, western New Brunswick. Canada, contain 13 ichnogenera (15 ichnospecies), namely:- Chondrites ichnospp.. Cochi ichnus anguineus, Dictyodora scotica, Dictyodora tenuis, Dimorphichnus ichnosp., Ciockerichnus ichnosp., Cordia marina, Helminthopsis ichnosp., Muensteria ichnosp., Neonereites uniserialis, Nereites jacksoni, Paiaeophycus tubularis, Syncoprulus pharmaceus and Yakutatia emersoni. Of these, Dimorphichnus, Muensteria and Dictyodora have never previously been recorded in the Matapedia Basin and Dictyodora is recorded for the first time in North America. The total assemblage represents the most diverse ichnocoenosis yet recorded from Paleozoic slope deposits. Sin: la rlviAre Tobique, dans l'ouest du Nouveau-Brunswick, au Canada, les flyschs du Groupe de MatapAdia appartenant au Bassin de MatapAdia, dAposAs en contexte de talus et d'age tardiordovicien A Aosilurien, ont livrA 13 ichnogenres (15 ichnoespAces), savoir; Chondrites ichnospp., Cochlichnus anguineus, Dictyodora scotica, Dictyodora tenuis, Dimorphichnus ichnosp., Ciockerichnus ichnosp., Gordia marina, Helminthopsis ichnosp., Muensteria ichnosp., Neonereites uniseriai is, Nereites jacksoni, Paiaeophycus tubularis, Syncoprulus pharmaceus and Yakutatia emersoni. Parmi ceux-ci, Dimophichnus, Muensteria et Dictyodora n'ont jamais AtA signalAs dans le Bassin de MatapAdia; il sagit, de plus, de la premier decouverte de Dictyodora en AmArique du Nord. -
Attribute of Trace Fossils of Laisong Flysch Sediments, Manipur, India
Attribute of trace fossils of Laisong flysch sediments, Manipur, India Kumar S Khaidem1, Hemanta S Rajkumar2,∗ and Ibotombi Soibam3 1Department of Geology, DM College of Science, Imphal 795 001, India. 2Department of Geology, United College Lambung, Chandel 795 127, India. 3Department of Earth Sciences, Manipur University, Canchipur 795 003, India. ∗Corresponding author. e-mail: [email protected] The depositional basin in which the Late Eocene–Early Oligocene Laisong flysch sediments Barail Group, Manipur region (Indo-Myanmar ranges) have been deposited is generally considered to be of deep marine environment. However, field observation indicates the presence of many shallow environment signature characteristics of marginal to sublittoral marine settings, in addition to the general occurrence of deep marine turbidites. To address this aspect, ichnological analyses of the Laisong Formation has been attempted for elucidating palaeoenvironmental setting prevalent during the deposition of these sediments. Presence of 36 ichnospecies belonging to 33 ichnogenera has so far been identified. The ichnospecies may be grouped into different ichnofacies such as Skolithos–Cruziana mixed ichnofacies, Cruziana ichnofa- cies, Skolithos ichnofacies, Zoophycos ichnofacies, Nereites ichnofacies and Teredolites ichnofacies which decrease in abundance in this order of sequence with Skolithos–Cruziana mixed ichnofacies being the most dominant. The above-mentioned ichnofacies are found associated with sedimentary structures such as large sole marks, parallel laminations, massive and structureless beds, rip-up clasts, etc., which are characteristics of submarine fan deposits below the storm wave base and current ripples, herringbone structures, hummocky cross stratifications, pot casts, rain prints, etc., that marked shallow marginal marine setting such as tidal flats, deltas and shoreface. -
The Upper Ordovician Glaciation in Sw Libya – a Subsurface Perspective
J.C. Gutiérrez-Marco, I. Rábano and D. García-Bellido (eds.), Ordovician of the World. Cuadernos del Museo Geominero, 14. Instituto Geológico y Minero de España, Madrid. ISBN 978-84-7840-857-3 © Instituto Geológico y Minero de España 2011 ICE IN THE SAHARA: THE UPPER ORDOVICIAN GLACIATION IN SW LIBYA – A SUBSURFACE PERSPECTIVE N.D. McDougall1 and R. Gruenwald2 1 Repsol Exploración, Paseo de la Castellana 280, 28046 Madrid, Spain. [email protected] 2 REMSA, Dhat El-Imad Complex, Tower 3, Floor 9, Tripoli, Libya. Keywords: Ordovician, Libya, glaciation, Mamuniyat, Melaz Shugran, Hirnantian. INTRODUCTION An Upper Ordovician glacial episode is widely recognized as a significant event in the geological history of the Lower Paleozoic. This is especially so in the case of the Saharan Platform where Upper Ordovician sediments are well developed and represent a major target for hydrocarbon exploration. This paper is a brief summary of the results of fieldwork, in outcrops across SW Libya, together with the analysis of cores, hundreds of well logs (including many high quality image logs) and seismic lines focused on the uppermost Ordovician of the Murzuq Basin. STRATIGRAPHIC FRAMEWORK The uppermost Ordovician section is the youngest of three major sequences recognized widely across the entire Saharan Platform: Sequence CO1: Unconformably overlies the Precambrian or Infracambrian basement. It comprises the possible Upper Cambrian to Lowermost Ordovician Hassaouna Formation. Sequence CO2: Truncates CO1 along a low angle, Type II unconformity. It comprises the laterally extensive and distinctive Lower Ordovician (Tremadocian-Floian?) Achebayat Formation overlain, along a probable transgressive surface of erosion, by interbedded burrowed sandstones, cross-bedded channel-fill sandstones and mudstones of Middle Ordovician age (Dapingian-Sandbian), known as the Hawaz Formation, and interpreted as shallow-marine sediments deposited within a megaestuary or gulf. -
X Congreso Argentino De Paleontología Y Bioestratigrafía VII Congreso Latinoamericano De Paleontología La Plata, Argentina - Septiembre De 2010
X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología La Plata, Argentina - Septiembre de 2010 Financian Auspician 1 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología La Plata, Argentina - Septiembre de 2010 2 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología La Plata, Argentina - Septiembre de 2010 3 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología La Plata, Argentina - Septiembre de 2010 X Congreso Argentino de Paleontología y Bioestratigrafía y VII Congreso Latinoamericano de Paleontología Resúmenes/coordinado por Sara Ballent ; Analia Artabe ; Franco Tortello. 1a ed. - La Plata: Museo de la Plata; Museo de la Plata, 2010. 238 p. + CD-ROM; 28x20 cm. ISBN 978-987-95849-7-2 1. Paleontología. 2. Bioestratigrafía. I. Ballent, Sara , coord. II. Artabe, Analia, coord. III. Tortello, Franco, coord. CDD 560 Fecha de catalogación: 27/08/2010 4 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología La Plata, Argentina - Septiembre de 2010 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología Declarado de Interés Municipal, La Plata (Decreto N° 1158) 5 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología La Plata, Argentina - Septiembre de 2010 6 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología La Plata, Argentina - Septiembre de 2010 X Congreso Argentino de Paleontología y Bioestratigrafía VII Congreso Latinoamericano de Paleontología Prólogo Una vez más el Congreso Argentino de Paleontología y Bioestratigrafía y el Congreso Latino- americano de Paleontología se realizan de manera conjunta. -
Evaluating the Role of Tectonics, Eustasy, and Climate On
This manuscript is a preprint and has been submitted to Basin Research for peer review. Please note that, this manuscript has to be formally accepted for publication. Subsequent versions may have slight differences in content according to the peer review process. If accepted, the final version of this manuscript will be available via the ‘Peer-reviewed Publication DOI’ link on the right information panel of this website. We welcome feedback on the content of this manuscript. Please feel free to contact any of the authors. EVALUATING THE ROLE OF TECTONICS, EUSTASY, AND CLIMATE ON THE MAASTRICHTIAN-DANIAN TRANSGRESSION IN THE MAGALLANES- AUSTRAL BASIN (CHILEAN PATAGONIA) Huber A. Rivera1, 2, *, Jacobus P. Le Roux1, Marcelo Farías1, Néstor M. Gutiérrez1, Alejandro Sánchez3, Sylvia Palma-Heldt4, Lissett Celle1 1Departamento de Geología, FCFM, Universidad de Chile, Plaza Ercilla 803, Santiago, Chile 2Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, 38000 Grenoble, France 3Departamento de Ingeniería en Minas, Universidad de Santiago de Chile, Av. O'Higgins 3363, Estación Central, Santiago, Chile 4Departamento de Ciencias de la Tierra, Universidad de Concepción, Barrio Universitario S/N°, Concepción, Chile *Corresponding author: [email protected]; [email protected] Page 1 of 65 Basin Research 1 2 3 Evaluating the role of tectonics, eustasy, and climate on the Maastrichtian-Danian 4 5 6 transgression in the Magallanes-Austral Basin (Chilean Patagonia) 7 8 9 Huber A. Rivera1, 2, *, Jacobus P. Le Roux1, Marcelo Farías1, Néstor M. Gutiérrez1, 10 3 4 1 11 Alejandro Sánchez , Sylvia Palma-Heldt , Lissett Celle 12 13 1Departamento de Geología, FCFM, Universidad de Chile, Plaza Ercilla 803, Santiago, Chile 14 15 2Univ. -
Trace Fossils in the Cretaceous-Eocene Flysch of the Sinop-Boyabat Basin, Central Pontides, Turkey
TRACE FOSSILS IN THE CRETACEOUS-EOCENE FLYSCH OF THE SINOP-BOYABAT BASIN,* CENTRAL PONTIDES, TURKEY Alfred UCHMAN1, Nils E. JANBU2 & Wojciech NEMEC2 1 Institute of Geological Sciences, Jagiellonian University, Oleandry 2a, 30-063 Kraków, Poland; [email protected] 2 Department of Earth Science, University of Bergen, Allegaten 4, N-5007 Bergen, Norway; [email protected]; wojtek. nemec@geo. uib. no Uchman, A., Janbu, N. E. & Nemec, W., 2004. Trace fossils in the Cretaceous-Eocene flysch of the Sinop-Boyabat Basin, Central Pontides, Turkey. Annales Societatis Geologorum Poloniae, 74, 197-235. Abstract: Sixty six ichnotaxa have been recognized in Barremian-Lutetian deep-marine deposits of the Sinop- Boyabat Basin, north-central Turkey, which evolved from a backarc rift into a retroarc foreland, with two episodes of major shallowing. The blackish-grey shales of the ęaglayan Fm (Barremian-Cenomanian) contain low- diversity traces fossils of mobile sediment feeders influenced by low oxygenation. One of the oldest occurrences of Scolicia indicates early adaptation to burrowing in organic-rich mud. The “normal” flysch of the Coniacian- Campanian Yemięlięay Fm bears a low-diversity Nereites ichnofacies influenced by volcanic activity. The Maastrichtian-Late Palaeocene carbonate flysch of the Akveren Fm contains a Nereites ichnofacies of moderate diversity, which is impoverished in the uppermost part, where tempestites indicate marked shallowing. The overlying variegated muddy flysch of the Atbaęi Fm (latest Palaeocene-earliest Eocene) bears an impoverished Nereites ichnofacies, which is attributed to oligotrophy and reduced preservation potential. The sand-rich silici- clastic flysch of the Kusuri Fm (Early-Middle Eocene) bears a high-diversity Nereites ichnofacies, except for the topmost part, where tempestites and littoral bioclastic limestone reflect rapid shallowing due to the tectonic closure of the basin.