Theropods, mesoeucrocodiles and pterosaurs (along with titanosaurian sauropods) are found in two overbank flood deposited mottled muds/shale units (alternated by meandering river deposited sandstone unit) of the lates...Theropods, mesoeucrocodiles and pterosaurs (along with titanosaurian sauropods) are found in two overbank flood deposited mottled muds/shale units (alternated by meandering river deposited sandstone unit) of the latest Maastrichtian (67 - 66 Ma) Vitakri Formation, Barkhan District, Balochistan, Pakistan. These vertebrates coexisted under the Cretaceous-Paleogene boundary line of control and became extinct as mass extinction. Previously these taxa lack the detail description but here theropods, mesoeucrocodiles and pterosaur from Pakistan are being described well with large photographs which provide better understanding of fauna from Pakistan and comparison with coeval taxa from Indo-Pakistan subcontinent. These fauna with associated cranial and postcranial skeletons are significant for Gondwanan paleobiogeography and phylogenetic studies.展开更多
Shallow carbonate deposits(Tarbur Formation)were formed in the Zagros foreland basin with dynamic tectonics during the Maastrichtian age.From the viewpoint of reconstruction of depositional conditions in these deposit...Shallow carbonate deposits(Tarbur Formation)were formed in the Zagros foreland basin with dynamic tectonics during the Maastrichtian age.From the viewpoint of reconstruction of depositional conditions in these deposits,studies of biostratigraphy,microfacies,microtaphofacies,and sequence stratigraphy were performed in a single area at Tang-e Shabi Khoon,northwest of Zagros.Based on the identification of two assemblage zones consisting of benthic foraminifera in these strata,the formation was deposited during the middle to late Maastrichtian.The number of cycles in test size and type of coiling in Loftusia decreased from the study area toward the northwest of the Neotethys basin.The input of clastic sediments affected the distribution of Loftusia and rudists in the study area.Nine microfacies,six microtaphofacies,and one terrigenous facies(shale)were identified based on the sedimentary features.These deposits of the middle-late Maastrichtian were deposited on a homoclinal carbonate ramp.The platform can be divided into restricted and semi-restricted lagoon,shoal,and open marine environments.In the study area,the deposits of the Tarbur Formation were deposited during four third-order depositional sequences.Local fault activities affected the formation of depositional sequences in the study area.展开更多
Pterosaur bones are for the first time reported from the Tremp Syncline (Spain) and the southern Pyrenees. They come from the Torrebilles-2 site (Isona, Lleida Province) in the upper Maastrichtian part of the Trem...Pterosaur bones are for the first time reported from the Tremp Syncline (Spain) and the southern Pyrenees. They come from the Torrebilles-2 site (Isona, Lleida Province) in the upper Maastrichtian part of the Tremp Formation, which falls within the C29r magnetochron. Fragmentary long bones are referred to the Pterosauria based on their cortical thinness, micro-architecture, and histological features. They belong to very large to possibly giant individuals. The most complete specimen is possibly a partial right femur. The review of the Maastrichtian pterosaur record shows that only a few specimens can be referred to the C29r (which contains the K/Pg boundary). The identification of fragmentary remains could improve our knowledge about the abundance and distribution of these flying sauropsids just before the end-Cretaceous mass extinction.展开更多
The deep and confined Maastrichtian aquifer contains considerable groundwater resources. It stretches over nearly 200,000 km2, from the northern part of Mauritania to the South of Guinea Bissau where it becomes shallo...The deep and confined Maastrichtian aquifer contains considerable groundwater resources. It stretches over nearly 200,000 km2, from the northern part of Mauritania to the South of Guinea Bissau where it becomes shallow. The reservoir is composed mainly of coarse sands and sandstone interbedded with some clay units. The aquifer provides 40% of the total drinking water extracted from the different aquifers and nearly 800 wells equally distributed operate only in the top 50 m of the aquifer. Despite the importance of these resources for providing water in the rural and urban areas, the aquifer characteristics are not well defined. The present paper aims to define first the physical and chemical characteristics of the Maastrichtian aquifer. The reserve of the aquifer initially estimated at 350 billion m3, is reassessed using new data providing from cross sections realized as part of our research, through the Water Sectorial Project of the Ministry of Hydraulics. Data from oil wells and geophysical logging are used to investigate the geometry of the aquifer and the position of the fresh/salty water interface. The highest thickness of the aquifer is between 200 to 400 m and salty water is present below the fresh groundwater in the west side of the aquifer. In the Eastern side, potable water lies directly above the basement. The thickness of the aquifer increases from the west to the center, and then decreases towards the shallow basement rock in the South East. The average thickness is 250 m. Chemical data coming from pumping wells indicate high chloride (250 - 1600 mg/l) and fluoride content (1 - 5.5 mg/l). Therefore, the reassessment has to take into account the chemical aspect of the water.展开更多
In this work we try to clarify, and correlate between two Maastrichtian aged units, namely Digma and Safra Units from selected sections in western desert of Iraq. Taking in consideration the stratigraphic code of NASC...In this work we try to clarify, and correlate between two Maastrichtian aged units, namely Digma and Safra Units from selected sections in western desert of Iraq. Taking in consideration the stratigraphic code of NASCENT (2005), and the results of previous studies, nine criteria have been used for the correlation, as follow: 1- From lithostratigraphic point of view, Digma Formation (Fm.) mostly composed of dark grey to blackish gray, uniform Carbonates-dominated facies, while Safra unit is characterized by light yellowish brown mixed phosphatic- siliceous-siliciclastics and carbonates facies. 2- Digma Fm. is characterized by Benthonic foraminifera assemblages (Bulimmina sp., Siphogerinoides sp. & Bolivinoides sp. ), while Safra phosphatic unit is flourished by macrofossils assemblages and vertebrates (Oyster, fish teeth’s and bones). 3- The upper and lower boundaries of the Digma Fm. are conformable, and vice versa for Safra Unit. 4- Illite/Semctite mixed layers-Illite clays assemblage and Glauconitic are predominates in Digma Fm., while Sepiolite-palygorskite-Montmorillonite, are common in Safra Unit, without any Glauconitic mineralization. 5- Digma Fm. slightly influenced by neomorphism and micritization. On other hand, Safra facies extremely influenced by phosphatization, silicification, dolomitization, and neomorphism and carbonate-silica replacement of the original evaporate minerals. 6- The predominated foraminiferal wackestone and mudstone microfacies, within Digma facies associations, mostly indicate deep trough marine condition (Anah Graben). The mixed phosphatic-carbonates (Oyster coquina band) and siliciclastics facies, (occasionally cross laminated), mostly deposited in shallower water depth, on the Arabian platform and distal steepened ramp towards Rutba flanks. 7- Sequence boundary of type one and three is bounded the Safra Unit respectively from upper and lower parts. 8- Continuously deposited Sequence was detected from the parasequences of the Safra facies, and across Maastrichtian/Danian boundary (Trafawi Unit). 9- The paleo-configuration of the basin almost influenced by the reactivity of the Anah basement faults started in the Late Campanian, and combined by shallowing upwards sequences. The conclusion is that, Digma facies can be considered as local facial changes of the Shiranish Formation, while Safra unit can be considered as a lower Member of (L. Maastrichtian-Danian) Jeed Formation, which is coincides with the whole stratigraphic frame work of the Mediterranean segments of the Tethyan phosphatic realm.展开更多
The upper Cretaceous interval of the Khoman Formation in the Tamera well, Siwa area, Western Desert of Egypt was studied for the first time on the basis of calcareous nannofossils. Twenty-one nannofossil species were ...The upper Cretaceous interval of the Khoman Formation in the Tamera well, Siwa area, Western Desert of Egypt was studied for the first time on the basis of calcareous nannofossils. Twenty-one nannofossil species were identified from this interval. The study interval includes the Micula murus Zone, which is precisely dated as Late Maastrichtian age. The Micula murus Zone includes besides the marker species: Micula decussata, Watznaueria barnesae, Arkhangelsktella cymbiformis and relatively rare occurrences of Eiffellithus turrisieffellii, Cribrosphaerella ehrenbergii, Thoracosphaera operculata and Braarudosphaera bigelowii. The latest Maastrichtian Micula prinsi Zone is missing, and an unconformity surface is detected in this well. The high abundance of Micula decussata is indicative of very low surface productivity and high-stress environmental conditions. Several nannofossil species are recognized as cool water indicators such as Micula decussata, and Arkhangelsktella cymbiformis.展开更多
A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 bo...A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 boreholes distributed over the whole country. The aim was to 1) identify the water types and likely factors influencing the hydrochemistry, and 2) determine the suitability of groundwater for drinking and irrigation. Results showed that sodium, chloride, and fluoride are highly correlated with electrical conductivity (EC) reflecting the significant contribution of these elements to groundwater mineralization. The principal component analysis evidenced: 1) salinization processes (loaded by Na<sup>+</sup>, K<sup>+</sup>, EC, Cl<sup>-</sup>, F<sup>-</sup> and HCO<sub>3</sub>-</sup>) controlled by water/rock interaction, seawater intrusion and cation exchange reactions;2) dolomite dissolution loaded by the couple Ca<sup>2+</sup> and Mg<sup>2+</sup> and 3) localized mixing with upper aquifers and gypsum dissolution respectively loaded by NO<sub>3</sub>-</sup> and SO<sub>4</sub>2-</sup>. The hierarchical clustering analysis distinguished four clusters: 1) freshwater (EC = 594 μs/cm) with mixed-HCO<sub>3</sub> water type and ionic contents below WHO standard;2) brackish (Na-mixed) water type with moderate mineralization content (1310 μs/cm), 3) brackish (Na-Cl) water type depicted by high EC values (3292 μs/cm) and ionic contents above WHO and 4) saline water with Na-Cl water type and very high mineralization contents (5953 μs/cm). The mapping of the groundwater quality index indicated suitable zones for drinking accounting for 54% of the entire area. The occurrence of a central brackish band and its vicinity, which were characterized by high mineralization, yielded unsuitable groundwater for drinking and agricultural uses. The approach used in this study was valuable for assessing groundwater quality for drinking and irrigation, and it can be used for regional studies in other locations, particularly in shallow and vulnerable aquifers.展开更多
Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and othe...Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and other many minerals in different regions which need further exploitation and development. The construction of new water dams in different regions are vital (for availability of cheap electricity), because of available barren and fertile lands and wastage of water as flood. Further the installation of more cement industries in different regions of Indus Basin especially in middle Indus (Sulaiman Range where gypsum, clays and limestones can be available via belt) can increase export to receive more foreign exchange and make local cement cheap for the sustainable development of Pakistan. 31 stratigraphic sequential sections at different sections of Indus basins are presented to know the variation and local stratigraphy. Further here three new titanosaur taxa are being described. Saraikimasoom is based on snout;Gspsaurus, (Maojandino), Nicksaurus and Khanazeem are based on cranial, vertebral and appendicular elements;Balochisaurus, Marisaurus, Pakisaurus, and 3 new genera and species Imrankhanhero zilefatmi, Qaikshaheen masoomniazi and Ikqaumishan smqureshi based on vertebral and appendicular elements;and Sulaimanisaurus and Khetranisaurus based on only caudal vertebrae. Although Pakistani Titanosaurians seem to be proliferated found from one horizon of Vitakri Formation just below the K-Pg boundary they have a wide range of diagnostic features and key elements among titanosaurs which can be used for comparison and phylogenetic analyses with broad updated character data set of titanosaurs.展开更多
A sedimentological investigation was carried out to reconstruct the paleogeography of the Zagros Foreland Basin.Based on the study of more than 1000 rock samples,nine carbonate microfacies and three terrigenous facies...A sedimentological investigation was carried out to reconstruct the paleogeography of the Zagros Foreland Basin.Based on the study of more than 1000 rock samples,nine carbonate microfacies and three terrigenous facies were identified.The study reveals that the Maastrichtian succession was deposited in a widespread homoclinal ramp in the High Zagros Basin.Three(Gandom Kar area),two(Ardal area),seven(Gardbishe area),five(Shirmard area),two(Kuh-e-Kamaneh area),three(Kuh-e-Balghar area),and six(Murak area)of depositional sequences(3rd order)were identified.The thickness of the lowstand systems tract(LST)due to activities of local faults and subsidence in the southeast is more than in the central and northwest of the High Zagros Basin during the Early and Early Middle Maastrichtian.During the Middle Maastrichtian,the shallow and deep marine deposits were formed during the transgressive systems tract(TST)and highstand systems tract(HST)in this basin and the rate of subsidence in the center of this basin(Gardbishe area)is higher than in other areas and the platform was drowned in this area.The falling relative sea-level due to activities of local faults led to that marine deposits were absent in all parts of the High Zagros Basin(except the south part)during the Late Maastrichtian.Paleogeographical studies on the Zagros Basin during the Late Campanian-Maastrichtian showed the following results:shallow marine environments were developed in the southeast of this basin,and the turbidite,delta,and fluvial environments in the northwest were developed more than in other areas.展开更多
The worldwide record of Cretaceous Neornithes and Neornithine-like birds is both controversial and poorly understood.However,in recent years,the Antarctic continent has yielded a substantial number of Maastrichtian av...The worldwide record of Cretaceous Neornithes and Neornithine-like birds is both controversial and poorly understood.However,in recent years,the Antarctic continent has yielded a substantial number of Maastrichtian avian specimens,contributing significantly to our understanding of the early evolution of this group.Simultaneously,the keen interest and collaborative efforts of various paleornithologists have resulted in a wealth of knowledge,which we have thoroughly reviewed,updated,and discussed in the context of recent discoveries.展开更多
Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostr...Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostratigraphy provides an age for the formation of the Early Campanian (nannofossil zone UC15aTp) to Early Selandian (nannofossil zone NPS), and highlights the presence of the Campanian/Maastrichtian, Cretaceous/Tertiary (K/T), and Danian/Selandian boundaries in this intermediate palaeolatitude location. Micula murus was identified below the K/T boundary, but Micula prinsii and Nephrolithus frequens were not, which implies that the K/T boundary interval is not complete in the study area. These dates are in agreement with previous micropaleontological studies.展开更多
Eruptions of lava flows of Deccan large igneous province straddled the Cretaceous-Palaeogene boundary (K-Pg). Sediments associated at different stratigraphic levels within the lava piles of Deccan volcanic sequences (...Eruptions of lava flows of Deccan large igneous province straddled the Cretaceous-Palaeogene boundary (K-Pg). Sediments associated at different stratigraphic levels within the lava piles of Deccan volcanic sequences (DVS) are mainly terrestrial. We studied the sediments of Eastern and Central Deccan Volcanic Province, and the Malwa Plateau for tracking changes in reptilian tetrapods across the volcanism. The reptiles are mainly represented by abelisaurid-titanosaurid dinosaurs, Alethinophidia madtsoiia snakes, Notosuchian crocodylomorph Simosuchus, bothremydid Kurmademydinae turtles and Anguimorph and Scincomorphs lizards. The evidences suggest that the non-avian dinosaurs were adversely affected by the arrival of the first volcanic flows locally in the province either within C30N or C29R Maastrichtian. The abelisaurid theropods became extinct whereas a single or two species of titanosauriforme dinosaurs survived but eventually became extinct at least 350 ky before the K-Pg boundary with increasing volcanism. The madtsooid snakes and crocodylimorphs were also adversely affected with decline in their diversity and abundance, whereas the Bothremydid turtles survived the initial onslaught of Deccan volcanism and continued across the K-Pg boundary.展开更多
A section in the Zhepure Mountains near Old Tingri in SE-Tibet,ranging from the Upper Albian to Paleogene,was described in detail by Willems et al.(1996).These authors worked on the litho-and microfacies and set up th...A section in the Zhepure Mountains near Old Tingri in SE-Tibet,ranging from the Upper Albian to Paleogene,was described in detail by Willems et al.(1996).These authors worked on the litho-and microfacies and set up the biostratigraphical framework by planktonic foraminifera.Willems et al.(1996)established their section as a standard for southern Tibet and compared it to the Gamba area.During the 2004 Tibet-expedition of Chengdu University of Technology in China,in co-operation with Bremen and Kiel universities in Germany,the locality was revisited for the purpose of collecting invertebrate fossils.This field-work included only the Upper Cretaceous part of the Tingri section and its invertebrate faunal content.Until today almost no ammonite and inoceramid data existed for this section.This is true for most Cretaceous sections in Tibet,although the Upper Cretaceous succession was interpreted as shelf environment.which in other parts of the world contains rich faunas of these macrofossil groups.The newly discovered continuous record of rare ammonites and inoceramids is probably limited since the preservation in the wacke-and packstones is poor.In addition,sampling conditions were unfavorable and the environmental conditions disadvantageous for most groups of invertebrates,as possibly indicated by larger amounts of small bivalve debris(filaments)in the upper part of the Gamba Group.Although the collected fauna is sparse and poorly preserved,the following biostratigraphical data can be added to the hitherto described microfauna:Calycoceras?from the Upper Gamba Group is Late Cenomanian in age and is accompanied by indeterminable juvenile desmoceratids.Superjacent follows a record of the ammonite Forresteria sp.,indicating that this level in the upper part of the Gamba Group belongs to the Lower Coniacian.This supports the finding of Inoceramus(Cremnoceramus)waltersdorfensis?hannovrensis?from the same interval.Anagaudryceras?is an individual ammonite finding from the Zhepure Shanbei or Zhepure Shanpo Formation,corresponding to the Santonian-Maastrichtian part of the succession.展开更多
Recently, four coexisted titanosaurs from latest Maastrichtian Vitakri Lameta Formation of Indo-Pakistan are recognized as Isisaurus and Pakisaurus of large-sized slender pakisaurids, Saraikimasoom and Gspsaurus of th...Recently, four coexisted titanosaurs from latest Maastrichtian Vitakri Lameta Formation of Indo-Pakistan are recognized as Isisaurus and Pakisaurus of large-sized slender pakisaurids, Saraikimasoom and Gspsaurus of the smallest and medium sized transversely stocky gspsaurids. Gspsaurus pakistani based on associated skull (with conical teeth tapering gradually from base to tip), vertebral and appendicular elements found from Alam 19 locality of Vitakri area, Barkhan district, Balochistan, Pakistan, South Asia. Gspsaurus bears sufficient skeletal elements and can be used for evolutionary studies.展开更多
Almost complete skulls of most derived titanosaurs which provide complete teeth row are rare. Saraikimasoom vitakri is the smallest sized, the most derived titanosaurian sauropod based on very small sized 15 - 18 cm l...Almost complete skulls of most derived titanosaurs which provide complete teeth row are rare. Saraikimasoom vitakri is the smallest sized, the most derived titanosaurian sauropod based on very small sized 15 - 18 cm long and 7 - 9 cm high partial skull. Dorsal profile of skull inclined 40°anteriorly. It provides full teeth row with dental formula 4, 13/9-13. Saraikimasoom is the smallest titanosaur so far found from Indo-Pakistan subcontinent. Its height is about 2 meter, length 8 - 10 meter and weight about 5 tons. Saraikimasoom vitakri shows Gondwanan paleobiogeographic link with some endemic elements.展开更多
Induszalim bala is the first diagnostic mesoeucrocodile from Indo-Pakistan subcontinent having rostrum articulated with dentary symphysis and associated vertebrae and limb bones and provides facility for comparison wi...Induszalim bala is the first diagnostic mesoeucrocodile from Indo-Pakistan subcontinent having rostrum articulated with dentary symphysis and associated vertebrae and limb bones and provides facility for comparison with other mesoeucrocodiles. Induszalim is a medium to large sized mesoeucrocodile found in the latest Maastrichtian Vitakri Lameta Formation of Fort Munro Group just below Cretaceous-Paleogene boundary line. Induszalim has sufficient skeletal elements and can be used for phylogenetic studies. Induszalim shows Gondwanan paleobiogeographic affinity with some endemic elements.展开更多
Angiosperm evolved and diversified during Cretaceous. During this course of evolution and radiation, various pollen of uncertain origin had evolved. Aquilapollenites represents the early stock of angiosperms attaining...Angiosperm evolved and diversified during Cretaceous. During this course of evolution and radiation, various pollen of uncertain origin had evolved. Aquilapollenites represents the early stock of angiosperms attaining its acme with respect to diversity and dominance during Campanian and Maastrichtian age. It was globally present (except Antarctica) however more dominant in northern hemisphere (Canada, North America, Sakhlain Oblast and China). In India, the Aquilapollenites sp. is present in Maastrichtian aged deposits. The pollen affinity has been associated with Loranthaceae and Santalaceae plant families. Here, a comparative description of all the Aquilapollenites sp. comprising a wide range of morphological diversity has been discussed. The wider morphological diversity and ecological adaptability of Aquilapollenites sp. infer that it is globally significant and warrants a more detailed study.展开更多
Indo-Pakistan subcontinent is lucky to host the smallest, medium and large sized titanosaurian sauropod dinosaurs. Saraikimasoom is the smallest sized, and Gspsaurus is the medium sized transversely stocky, Pakisaurus...Indo-Pakistan subcontinent is lucky to host the smallest, medium and large sized titanosaurian sauropod dinosaurs. Saraikimasoom is the smallest sized, and Gspsaurus is the medium sized transversely stocky, Pakisaurus and Isisaurus are the large sized titanosaurs of South Asia. Pakisaurus balochistani is a slender type of pakisaurid titanosaurian based on associated vertebral and appendicular skeletons. Pakisaurus balochistani includes key elements like transversely thin or narrow tibia and ventrally not reduced tall caudal vertebrae, along with other elements which are significant for cladistic analysis.展开更多
文摘Theropods, mesoeucrocodiles and pterosaurs (along with titanosaurian sauropods) are found in two overbank flood deposited mottled muds/shale units (alternated by meandering river deposited sandstone unit) of the latest Maastrichtian (67 - 66 Ma) Vitakri Formation, Barkhan District, Balochistan, Pakistan. These vertebrates coexisted under the Cretaceous-Paleogene boundary line of control and became extinct as mass extinction. Previously these taxa lack the detail description but here theropods, mesoeucrocodiles and pterosaur from Pakistan are being described well with large photographs which provide better understanding of fauna from Pakistan and comparison with coeval taxa from Indo-Pakistan subcontinent. These fauna with associated cranial and postcranial skeletons are significant for Gondwanan paleobiogeography and phylogenetic studies.
基金the University of Isfahan for the financial support。
文摘Shallow carbonate deposits(Tarbur Formation)were formed in the Zagros foreland basin with dynamic tectonics during the Maastrichtian age.From the viewpoint of reconstruction of depositional conditions in these deposits,studies of biostratigraphy,microfacies,microtaphofacies,and sequence stratigraphy were performed in a single area at Tang-e Shabi Khoon,northwest of Zagros.Based on the identification of two assemblage zones consisting of benthic foraminifera in these strata,the formation was deposited during the middle to late Maastrichtian.The number of cycles in test size and type of coiling in Loftusia decreased from the study area toward the northwest of the Neotethys basin.The input of clastic sediments affected the distribution of Loftusia and rudists in the study area.Nine microfacies,six microtaphofacies,and one terrigenous facies(shale)were identified based on the sedimentary features.These deposits of the middle-late Maastrichtian were deposited on a homoclinal carbonate ramp.The platform can be divided into restricted and semi-restricted lagoon,shoal,and open marine environments.In the study area,the deposits of the Tarbur Formation were deposited during four third-order depositional sequences.Local fault activities affected the formation of depositional sequences in the study area.
基金supported by Ministerio de Ciencia e Innovación of the Spanish government (CGL2008-06533C03-01/02)the Departament de Cultura de la Generalitat de Catalunya
文摘Pterosaur bones are for the first time reported from the Tremp Syncline (Spain) and the southern Pyrenees. They come from the Torrebilles-2 site (Isona, Lleida Province) in the upper Maastrichtian part of the Tremp Formation, which falls within the C29r magnetochron. Fragmentary long bones are referred to the Pterosauria based on their cortical thinness, micro-architecture, and histological features. They belong to very large to possibly giant individuals. The most complete specimen is possibly a partial right femur. The review of the Maastrichtian pterosaur record shows that only a few specimens can be referred to the C29r (which contains the K/Pg boundary). The identification of fragmentary remains could improve our knowledge about the abundance and distribution of these flying sauropsids just before the end-Cretaceous mass extinction.
文摘The deep and confined Maastrichtian aquifer contains considerable groundwater resources. It stretches over nearly 200,000 km2, from the northern part of Mauritania to the South of Guinea Bissau where it becomes shallow. The reservoir is composed mainly of coarse sands and sandstone interbedded with some clay units. The aquifer provides 40% of the total drinking water extracted from the different aquifers and nearly 800 wells equally distributed operate only in the top 50 m of the aquifer. Despite the importance of these resources for providing water in the rural and urban areas, the aquifer characteristics are not well defined. The present paper aims to define first the physical and chemical characteristics of the Maastrichtian aquifer. The reserve of the aquifer initially estimated at 350 billion m3, is reassessed using new data providing from cross sections realized as part of our research, through the Water Sectorial Project of the Ministry of Hydraulics. Data from oil wells and geophysical logging are used to investigate the geometry of the aquifer and the position of the fresh/salty water interface. The highest thickness of the aquifer is between 200 to 400 m and salty water is present below the fresh groundwater in the west side of the aquifer. In the Eastern side, potable water lies directly above the basement. The thickness of the aquifer increases from the west to the center, and then decreases towards the shallow basement rock in the South East. The average thickness is 250 m. Chemical data coming from pumping wells indicate high chloride (250 - 1600 mg/l) and fluoride content (1 - 5.5 mg/l). Therefore, the reassessment has to take into account the chemical aspect of the water.
文摘In this work we try to clarify, and correlate between two Maastrichtian aged units, namely Digma and Safra Units from selected sections in western desert of Iraq. Taking in consideration the stratigraphic code of NASCENT (2005), and the results of previous studies, nine criteria have been used for the correlation, as follow: 1- From lithostratigraphic point of view, Digma Formation (Fm.) mostly composed of dark grey to blackish gray, uniform Carbonates-dominated facies, while Safra unit is characterized by light yellowish brown mixed phosphatic- siliceous-siliciclastics and carbonates facies. 2- Digma Fm. is characterized by Benthonic foraminifera assemblages (Bulimmina sp., Siphogerinoides sp. & Bolivinoides sp. ), while Safra phosphatic unit is flourished by macrofossils assemblages and vertebrates (Oyster, fish teeth’s and bones). 3- The upper and lower boundaries of the Digma Fm. are conformable, and vice versa for Safra Unit. 4- Illite/Semctite mixed layers-Illite clays assemblage and Glauconitic are predominates in Digma Fm., while Sepiolite-palygorskite-Montmorillonite, are common in Safra Unit, without any Glauconitic mineralization. 5- Digma Fm. slightly influenced by neomorphism and micritization. On other hand, Safra facies extremely influenced by phosphatization, silicification, dolomitization, and neomorphism and carbonate-silica replacement of the original evaporate minerals. 6- The predominated foraminiferal wackestone and mudstone microfacies, within Digma facies associations, mostly indicate deep trough marine condition (Anah Graben). The mixed phosphatic-carbonates (Oyster coquina band) and siliciclastics facies, (occasionally cross laminated), mostly deposited in shallower water depth, on the Arabian platform and distal steepened ramp towards Rutba flanks. 7- Sequence boundary of type one and three is bounded the Safra Unit respectively from upper and lower parts. 8- Continuously deposited Sequence was detected from the parasequences of the Safra facies, and across Maastrichtian/Danian boundary (Trafawi Unit). 9- The paleo-configuration of the basin almost influenced by the reactivity of the Anah basement faults started in the Late Campanian, and combined by shallowing upwards sequences. The conclusion is that, Digma facies can be considered as local facial changes of the Shiranish Formation, while Safra unit can be considered as a lower Member of (L. Maastrichtian-Danian) Jeed Formation, which is coincides with the whole stratigraphic frame work of the Mediterranean segments of the Tethyan phosphatic realm.
文摘The upper Cretaceous interval of the Khoman Formation in the Tamera well, Siwa area, Western Desert of Egypt was studied for the first time on the basis of calcareous nannofossils. Twenty-one nannofossil species were identified from this interval. The study interval includes the Micula murus Zone, which is precisely dated as Late Maastrichtian age. The Micula murus Zone includes besides the marker species: Micula decussata, Watznaueria barnesae, Arkhangelsktella cymbiformis and relatively rare occurrences of Eiffellithus turrisieffellii, Cribrosphaerella ehrenbergii, Thoracosphaera operculata and Braarudosphaera bigelowii. The latest Maastrichtian Micula prinsi Zone is missing, and an unconformity surface is detected in this well. The high abundance of Micula decussata is indicative of very low surface productivity and high-stress environmental conditions. Several nannofossil species are recognized as cool water indicators such as Micula decussata, and Arkhangelsktella cymbiformis.
文摘A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 boreholes distributed over the whole country. The aim was to 1) identify the water types and likely factors influencing the hydrochemistry, and 2) determine the suitability of groundwater for drinking and irrigation. Results showed that sodium, chloride, and fluoride are highly correlated with electrical conductivity (EC) reflecting the significant contribution of these elements to groundwater mineralization. The principal component analysis evidenced: 1) salinization processes (loaded by Na<sup>+</sup>, K<sup>+</sup>, EC, Cl<sup>-</sup>, F<sup>-</sup> and HCO<sub>3</sub>-</sup>) controlled by water/rock interaction, seawater intrusion and cation exchange reactions;2) dolomite dissolution loaded by the couple Ca<sup>2+</sup> and Mg<sup>2+</sup> and 3) localized mixing with upper aquifers and gypsum dissolution respectively loaded by NO<sub>3</sub>-</sup> and SO<sub>4</sub>2-</sup>. The hierarchical clustering analysis distinguished four clusters: 1) freshwater (EC = 594 μs/cm) with mixed-HCO<sub>3</sub> water type and ionic contents below WHO standard;2) brackish (Na-mixed) water type with moderate mineralization content (1310 μs/cm), 3) brackish (Na-Cl) water type depicted by high EC values (3292 μs/cm) and ionic contents above WHO and 4) saline water with Na-Cl water type and very high mineralization contents (5953 μs/cm). The mapping of the groundwater quality index indicated suitable zones for drinking accounting for 54% of the entire area. The occurrence of a central brackish band and its vicinity, which were characterized by high mineralization, yielded unsuitable groundwater for drinking and agricultural uses. The approach used in this study was valuable for assessing groundwater quality for drinking and irrigation, and it can be used for regional studies in other locations, particularly in shallow and vulnerable aquifers.
文摘Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and other many minerals in different regions which need further exploitation and development. The construction of new water dams in different regions are vital (for availability of cheap electricity), because of available barren and fertile lands and wastage of water as flood. Further the installation of more cement industries in different regions of Indus Basin especially in middle Indus (Sulaiman Range where gypsum, clays and limestones can be available via belt) can increase export to receive more foreign exchange and make local cement cheap for the sustainable development of Pakistan. 31 stratigraphic sequential sections at different sections of Indus basins are presented to know the variation and local stratigraphy. Further here three new titanosaur taxa are being described. Saraikimasoom is based on snout;Gspsaurus, (Maojandino), Nicksaurus and Khanazeem are based on cranial, vertebral and appendicular elements;Balochisaurus, Marisaurus, Pakisaurus, and 3 new genera and species Imrankhanhero zilefatmi, Qaikshaheen masoomniazi and Ikqaumishan smqureshi based on vertebral and appendicular elements;and Sulaimanisaurus and Khetranisaurus based on only caudal vertebrae. Although Pakistani Titanosaurians seem to be proliferated found from one horizon of Vitakri Formation just below the K-Pg boundary they have a wide range of diagnostic features and key elements among titanosaurs which can be used for comparison and phylogenetic analyses with broad updated character data set of titanosaurs.
基金the University of Isfahan for the financial support。
文摘A sedimentological investigation was carried out to reconstruct the paleogeography of the Zagros Foreland Basin.Based on the study of more than 1000 rock samples,nine carbonate microfacies and three terrigenous facies were identified.The study reveals that the Maastrichtian succession was deposited in a widespread homoclinal ramp in the High Zagros Basin.Three(Gandom Kar area),two(Ardal area),seven(Gardbishe area),five(Shirmard area),two(Kuh-e-Kamaneh area),three(Kuh-e-Balghar area),and six(Murak area)of depositional sequences(3rd order)were identified.The thickness of the lowstand systems tract(LST)due to activities of local faults and subsidence in the southeast is more than in the central and northwest of the High Zagros Basin during the Early and Early Middle Maastrichtian.During the Middle Maastrichtian,the shallow and deep marine deposits were formed during the transgressive systems tract(TST)and highstand systems tract(HST)in this basin and the rate of subsidence in the center of this basin(Gardbishe area)is higher than in other areas and the platform was drowned in this area.The falling relative sea-level due to activities of local faults led to that marine deposits were absent in all parts of the High Zagros Basin(except the south part)during the Late Maastrichtian.Paleogeographical studies on the Zagros Basin during the Late Campanian-Maastrichtian showed the following results:shallow marine environments were developed in the southeast of this basin,and the turbidite,delta,and fluvial environments in the northwest were developed more than in other areas.
基金To the Universidad Nacional de La Plata PID N955,ANPCyT PICT 20170607,and CONICET PIP 0096 for partial support.
文摘The worldwide record of Cretaceous Neornithes and Neornithine-like birds is both controversial and poorly understood.However,in recent years,the Antarctic continent has yielded a substantial number of Maastrichtian avian specimens,contributing significantly to our understanding of the early evolution of this group.Simultaneously,the keen interest and collaborative efforts of various paleornithologists have resulted in a wealth of knowledge,which we have thoroughly reviewed,updated,and discussed in the context of recent discoveries.
基金The Erciyes University provided financial support for this study (Project No.FBT-06-24)
文摘Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostratigraphy provides an age for the formation of the Early Campanian (nannofossil zone UC15aTp) to Early Selandian (nannofossil zone NPS), and highlights the presence of the Campanian/Maastrichtian, Cretaceous/Tertiary (K/T), and Danian/Selandian boundaries in this intermediate palaeolatitude location. Micula murus was identified below the K/T boundary, but Micula prinsii and Nephrolithus frequens were not, which implies that the K/T boundary interval is not complete in the study area. These dates are in agreement with previous micropaleontological studies.
文摘Eruptions of lava flows of Deccan large igneous province straddled the Cretaceous-Palaeogene boundary (K-Pg). Sediments associated at different stratigraphic levels within the lava piles of Deccan volcanic sequences (DVS) are mainly terrestrial. We studied the sediments of Eastern and Central Deccan Volcanic Province, and the Malwa Plateau for tracking changes in reptilian tetrapods across the volcanism. The reptiles are mainly represented by abelisaurid-titanosaurid dinosaurs, Alethinophidia madtsoiia snakes, Notosuchian crocodylomorph Simosuchus, bothremydid Kurmademydinae turtles and Anguimorph and Scincomorphs lizards. The evidences suggest that the non-avian dinosaurs were adversely affected by the arrival of the first volcanic flows locally in the province either within C30N or C29R Maastrichtian. The abelisaurid theropods became extinct whereas a single or two species of titanosauriforme dinosaurs survived but eventually became extinct at least 350 ky before the K-Pg boundary with increasing volcanism. The madtsooid snakes and crocodylimorphs were also adversely affected with decline in their diversity and abundance, whereas the Bothremydid turtles survived the initial onslaught of Deccan volcanism and continued across the K-Pg boundary.
文摘A section in the Zhepure Mountains near Old Tingri in SE-Tibet,ranging from the Upper Albian to Paleogene,was described in detail by Willems et al.(1996).These authors worked on the litho-and microfacies and set up the biostratigraphical framework by planktonic foraminifera.Willems et al.(1996)established their section as a standard for southern Tibet and compared it to the Gamba area.During the 2004 Tibet-expedition of Chengdu University of Technology in China,in co-operation with Bremen and Kiel universities in Germany,the locality was revisited for the purpose of collecting invertebrate fossils.This field-work included only the Upper Cretaceous part of the Tingri section and its invertebrate faunal content.Until today almost no ammonite and inoceramid data existed for this section.This is true for most Cretaceous sections in Tibet,although the Upper Cretaceous succession was interpreted as shelf environment.which in other parts of the world contains rich faunas of these macrofossil groups.The newly discovered continuous record of rare ammonites and inoceramids is probably limited since the preservation in the wacke-and packstones is poor.In addition,sampling conditions were unfavorable and the environmental conditions disadvantageous for most groups of invertebrates,as possibly indicated by larger amounts of small bivalve debris(filaments)in the upper part of the Gamba Group.Although the collected fauna is sparse and poorly preserved,the following biostratigraphical data can be added to the hitherto described microfauna:Calycoceras?from the Upper Gamba Group is Late Cenomanian in age and is accompanied by indeterminable juvenile desmoceratids.Superjacent follows a record of the ammonite Forresteria sp.,indicating that this level in the upper part of the Gamba Group belongs to the Lower Coniacian.This supports the finding of Inoceramus(Cremnoceramus)waltersdorfensis?hannovrensis?from the same interval.Anagaudryceras?is an individual ammonite finding from the Zhepure Shanbei or Zhepure Shanpo Formation,corresponding to the Santonian-Maastrichtian part of the succession.
文摘Recently, four coexisted titanosaurs from latest Maastrichtian Vitakri Lameta Formation of Indo-Pakistan are recognized as Isisaurus and Pakisaurus of large-sized slender pakisaurids, Saraikimasoom and Gspsaurus of the smallest and medium sized transversely stocky gspsaurids. Gspsaurus pakistani based on associated skull (with conical teeth tapering gradually from base to tip), vertebral and appendicular elements found from Alam 19 locality of Vitakri area, Barkhan district, Balochistan, Pakistan, South Asia. Gspsaurus bears sufficient skeletal elements and can be used for evolutionary studies.
文摘Almost complete skulls of most derived titanosaurs which provide complete teeth row are rare. Saraikimasoom vitakri is the smallest sized, the most derived titanosaurian sauropod based on very small sized 15 - 18 cm long and 7 - 9 cm high partial skull. Dorsal profile of skull inclined 40°anteriorly. It provides full teeth row with dental formula 4, 13/9-13. Saraikimasoom is the smallest titanosaur so far found from Indo-Pakistan subcontinent. Its height is about 2 meter, length 8 - 10 meter and weight about 5 tons. Saraikimasoom vitakri shows Gondwanan paleobiogeographic link with some endemic elements.
文摘Induszalim bala is the first diagnostic mesoeucrocodile from Indo-Pakistan subcontinent having rostrum articulated with dentary symphysis and associated vertebrae and limb bones and provides facility for comparison with other mesoeucrocodiles. Induszalim is a medium to large sized mesoeucrocodile found in the latest Maastrichtian Vitakri Lameta Formation of Fort Munro Group just below Cretaceous-Paleogene boundary line. Induszalim has sufficient skeletal elements and can be used for phylogenetic studies. Induszalim shows Gondwanan paleobiogeographic affinity with some endemic elements.
文摘Angiosperm evolved and diversified during Cretaceous. During this course of evolution and radiation, various pollen of uncertain origin had evolved. Aquilapollenites represents the early stock of angiosperms attaining its acme with respect to diversity and dominance during Campanian and Maastrichtian age. It was globally present (except Antarctica) however more dominant in northern hemisphere (Canada, North America, Sakhlain Oblast and China). In India, the Aquilapollenites sp. is present in Maastrichtian aged deposits. The pollen affinity has been associated with Loranthaceae and Santalaceae plant families. Here, a comparative description of all the Aquilapollenites sp. comprising a wide range of morphological diversity has been discussed. The wider morphological diversity and ecological adaptability of Aquilapollenites sp. infer that it is globally significant and warrants a more detailed study.
文摘Indo-Pakistan subcontinent is lucky to host the smallest, medium and large sized titanosaurian sauropod dinosaurs. Saraikimasoom is the smallest sized, and Gspsaurus is the medium sized transversely stocky, Pakisaurus and Isisaurus are the large sized titanosaurs of South Asia. Pakisaurus balochistani is a slender type of pakisaurid titanosaurian based on associated vertebral and appendicular skeletons. Pakisaurus balochistani includes key elements like transversely thin or narrow tibia and ventrally not reduced tall caudal vertebrae, along with other elements which are significant for cladistic analysis.