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43-669: The Pieniny Klippen Belt emerges from beneath the Neogene sediments of the Vienna basin near Podbranč in western Slovakia and continues eastward to Poland , where it bends and returns to Slovakia in the area of Pieniny . The klippen belt then continues to Ukraine and ends in Romania . In some places it is covered with younger deposits, for example in the Podhale basin in Poland, or in

86-559: A series of continental glaciations in the Quaternary Period that followed. In ICS terminology, from upper (later, more recent) to lower (earlier): The Pliocene Epoch is subdivided into two ages: The Miocene Epoch is subdivided into six ages: In different geophysical regions of the world, other regional names are also used for the same or overlapping ages and other timeline subdivisions. The terms Neogene System (formal) and Upper Tertiary System (informal) describe

129-601: Is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period 23.03 million years ago ( Mya ) to the beginning of the present Quaternary Period 2.58 million years ago. It is the second period of the Cenozoic and the eleventh period of the Phanerozoic . The Neogene is sub-divided into two epochs , the earlier Miocene and the later Pliocene . Some geologists assert that

172-481: Is due to the comparatively fine divisibility of time units as time approaches the present, and due to geological preservation that causes the youngest sedimentary geological record to be preserved over a much larger area and to reflect many more environments than the older geological record. By dividing the Cenozoic Era into three (arguably two) periods ( Paleogene , Neogene, Quaternary ) instead of seven epochs,

215-479: Is it particularly evident that a true systematic decline was ever in place, especially with the discovery of smaller pterosaur species. Several old mammal groups began to disappear, with the last eutriconodonts occurring in the Campanian of North America . In the northern hemisphere, cimolodont , multituberculates , metatherians and eutherians were the dominant mammals, with the former two groups being

258-671: Is named after creta , the Latin word for the white limestone known as chalk . The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Due to plate tectonics ,

301-702: Is often seen as an analogous climate to the projected climate of the near future as a result of anthropogenic global warming . Towards the end of the Pliocene, decreased heat transport towards the Antarctic resulting from a weakening of the Indonesian Throughflow (ITF) cooled the Earth, a process that exacerbated itself in a positive feedback as sea levels dropped and the ITF diminished and further limited

344-823: The Alpine orogeny . The oldest phase is called the Laramide phase or Jarmuta phase and occurred in the Cretaceous and Paleogene periods. It caused thrusting of the nappes . The second phase is called the Savian or Helvetian phase. It was induced by subduction of the Northern Penninic ocean and caused the formation of the Carpathian Flysch Belt . The Pieniny Klippen Belt is divided into numerous tectonic units, but only few of them occur throughout

387-890: The Middle Jurassic to Lowermost Cretaceous an elevated continental ribbon called the Czorsztyn Ridge evolved due to the thermal uplift and continental break-up at the southern side of the Czorsztyn Ridge. Rifting resulted in the opening of basinal area called the Kysuca basin or Vahic Ocean (South Penninic or Piemont ocean equivalent) to the south of the Oravic area. In the Upper Jurassic entire Oravic domain began to thermally subside. Since Lowermost Cretaceous time probably an asymmetrical rifting affected

430-793: The Paleogene . The Early Miocene was relatively cool; Early Miocene mid-latitude seawater and continental thermal gradients were already very similar to those of the present. During the Middle Miocene , Earth entered a warm phase known as the Middle Miocene Climatic Optimum (MMCO), which was driven by the emplacement of the Columbia River Basalt Group . Around 11 Ma, the Middle Miocene Warm Interval gave way to

473-842: The Upper Cretaceous to Paleocene the Vahic Ocean began to close. The Oravic units were detached from its subducting basement and formed a fold and thrust belt . After first phase of folding and thrusting sedimentation of turbiditic sequences was restored. Whole area was again deformed in second phase of orogeny in the Upper Paleogene to Lower Miocene when sinistral transpression and amalgamation with hinterland part of closed Magura Ocean caused formation of typical "klippen" tectonic style due to counterclockwise rotation of ALCAPA microplate. During this times several subduction related calc-alcaline volcanoes locally evolved in

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516-545: The Vihorlat Mountains in Slovakia. Klippes , which are the most characteristic features of the belt, are Jurassic to lower Cretaceous lenses - rigid blocks of limestone , tectonically separated from their unknown substratum. These blocks are also cropping out in tectonic windows in the overlying middle Cretaceous to Paleogene sediments. Strong tectonic deformation is a result of two main phases during

559-590: The Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia . India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Antarctica seem to have remained connected and began to drift away from Africa and South America. Europe

602-743: The Cretaceous Period derived from the German name Kreidezeit , and T is the abbreviation for the Tertiary Period (a historical term for the period of time now covered by the Paleogene and Neogene periods). The event marks the end of the Mesozoic Era and the beginning of the Cenozoic Era. "Tertiary" being no longer recognized as a formal time or rock unit by the International Commission on Stratigraphy ,

645-704: The Gelasian Age, which was formerly considered part of the Neogene Period and Pliocene Epoch. Thus the Neogene Period ends bounding the succeeding Quaternary Period at 2.58 Mya. Upper Cretaceous The Late Cretaceous (100.5–66 Ma ) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale . Rock strata from this epoch form the Upper Cretaceous Series . The Cretaceous

688-850: The K-T event is now called the Cretaceous—Paleogene (or K-Pg) extinction event by many researchers. Non- avian dinosaur fossils are found only below the Cretaceous–Paleogene boundary and became extinct immediately before or during the event. A very small number of dinosaur fossils have been found above the Cretaceous–Paleogene boundary, but they have been explained as reworked fossils , that is, fossils that have been eroded from their original locations then preserved in later sedimentary layers. Mosasaurs , plesiosaurs , pterosaurs and many species of plants and invertebrates also became extinct. Mammalian and bird clades passed through

731-558: The Miocene-Pliocene boundary. The first hominins , the ancestors of humans, may have appeared in southern Europe and migrated into Africa. The first humans (belonging to the species Homo habilis ) appeared in Africa near the end of the period. About 20 million years ago gymnosperms in the form of some conifer and cycad groups started to diversify and produce more species due to the changing conditions. In response to

774-777: The Neogene and the Pliocene end at 2.58 Ma, that the Gelasian be transferred to the Pleistocene, and the Quaternary be recognized as the third period in the Cenozoic, citing key changes in Earth's climate, oceans, and biota that occurred 2.58 Ma and its correspondence to the Gauss-Matuyama magnetostratigraphic boundary . In 2006 ICS and INQUA reached a compromise that made Quaternary a sub-era, subdividing Cenozoic into

817-744: The Neogene cannot be clearly delineated from the modern geological period, the Quaternary . The term "Neogene" was coined in 1853 by the Austrian palaeontologist Moritz Hörnes (1815–1868). The earlier term Tertiary Period was used to define the span of time now covered by Paleogene and Neogene and, despite no longer being recognized as a formal stratigraphic term , "Tertiary" still sometimes remains in informal use. During this period, mammals and birds continued to evolve into modern forms, while other groups of life remained relatively unchanged. The first humans ( Homo habilis ) appeared in Africa near

860-618: The North American varieties. Pachycephalosaurs were also present in both North America and Asia. Dromaeosaurids shared the same geographical distribution, and are well documented in both Mongolia and Western North America. Additionally therizinosaurs (known previously as segnosaurs) appear to have been in North America and Asia. Gondwana held a very different dinosaurian fauna, with most predators being abelisaurids and carcharodontosaurids ; and titanosaurs being among

903-562: The Pliocene Warm Interval (PWI), interrupting the longer-term cooling trend. The Pliocene Thermal Maximum (PTM) occurred between 3.3 and 3.0 Ma. During the Pliocene, Green Sahara phases of wet conditions in North Africa were frequent and occurred about every 21 kyr, being especially intense when Earth's orbit's eccentricity was high. The PWI had similar levels of atmospheric carbon dioxide to contemporary times and

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946-680: The area to the North of the Czorsztyn Ridge where a Magura basin (North Penninic or Valais Ocean equivalent) started to evolve. During the Middle Cretaceous thermal subsidence of the Czorsztyn Ridge caused its development into a pelagic high. In Turonian times frontal elements of the Fatric Nappe System of the Inner Western Carpathians were emplaced onto the southern parts of the Vahic Ocean. In

989-607: The area. Later sinistral transtension and lateral extension modified the structure of the belt during the Late Miocene and Pliocene . Extensional deformation on the eastern and western edge of the belt interacted with development of the Vienna and Transcarpathian basin . After the marine regression at the end of Miocene younger marls and turbidites were eroded faster than more competent Jurassic limestones forming distinctly looking klippes. Neogene The Neogene ( / ˈ n iː . ə dʒ iː n / NEE -ə-jeen , )

1032-544: The atmosphere, C 4 plants expanded and reached ecological dominance in grasslands during the last 10 million years. Also Asteraceae (daisies) went through a significant adaptive radiation . Eucalyptus fossil leaves occur in the Miocene of New Zealand, where the genus is not native today, but have been introduced from Australia. The Neogene traditionally ended at the end of the Pliocene Epoch, just before

1075-524: The boundary with few extinctions, and evolutionary radiation from those Maastrichtian clades occurred well past the boundary. Rates of extinction and radiation varied across different clades of organisms. Many scientists hypothesize that the Cretaceous–Paleogene extinctions were caused by catastrophic events such as the massive asteroid impact that caused the Chicxulub crater , in combination with increased volcanic activity , such as that recorded in

1118-464: The cooler, seasonal climate, tropical plant species gave way to deciduous ones and grasslands replaced many forests. Grasses therefore greatly diversified, and herbivorous mammals evolved alongside it, creating the many grazing animals of today such as horses , antelope , and bison . Ice age mammals like the mammoths and woolly rhinoceros were common in Pliocene . With lower levels of CO 2 in

1161-704: The deep marine Kysuca unit it forms a continental domain called the Oravicum , which is geometrically equivalent to the Briançonnais microcontinent in the Western and Central Alps. Reconstruction of the older phases of development is not possible because of absence of pre- triassic rocks. The development of Pieniny Klippen Belt started on passive margin of European platform in Lower Jurassic with rifting and tectonic subsidence of Oravic unit. During

1204-401: The dominant herbivores. Spinosaurids were also present during this time. Birds became increasingly common, diversifying in a variety of enantiornithe and ornithurine forms. Early Neornithes such as Vegavis co-existed with forms as bizarre as Yungavolucris and Avisaurus . Though mostly small, marine Hesperornithes became relatively large and flightless, adapted to life in

1247-645: The end of the period. Some continental movements took place, the most significant event being the connection of North and South America at the Isthmus of Panama , late in the Pliocene. This cut off the warm ocean currents from the Pacific to the Atlantic Ocean, leaving only the Gulf Stream to transfer heat to the Arctic Ocean . The global climate cooled considerably throughout the Neogene, culminating in

1290-498: The entire belt. The oldest rocks of the Klippen belt are Middle Jurassic to upper Cretaceous . They are in normal stratigraphical positions, with only minor hiatus . Large scale crustal shortening caused rocks of different tectonic units and origin to be thrusted over each other and now lying juxtaposed. These tectonic units are: The Czorsztyn unit has the shallowest marine facies. Together with smaller continental slope units and

1333-467: The heat transported southward by the Leeuwin Current . By the end of the period the first of a series of glaciations of the current Ice Age began. Marine and continental flora and fauna have a modern appearance. The reptile group Choristodera went extinct in the early part of the period, while the amphibians known as Allocaudata disappeared at the end of it. Neogene also marked the end of

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1376-636: The most common mammals in North America. In the southern hemisphere there was instead a more complex fauna of dryolestoids , gondwanatheres and other multituberculates and basal eutherians ; monotremes were presumably present, as was the last of the haramiyidans , Avashishta . Mammals, though generally small, ranged into a variety of ecological niches, from carnivores ( Deltatheroida ), to mollusc-eater ( Stagodontidae ), to herbivores (multituberculates, Schowalteria , Zhelestidae and Mesungulatidae ) to highly atypical cursorial forms ( Zalambdalestidae , Brandoniidae ). True placentals evolved only at

1419-486: The much cooler Late Miocene. The ice caps on both poles began to grow and thicken, a process enhanced by positive feedbacks from increased formation of sea ice. Between 7 and 5.3 Ma, a decrease in global temperatures termed the Late Miocene Cooling (LMC) ensued, driven by decreases in carbon dioxide concentrations. During the Pliocene, from about 5.3 to 2.7 Ma, another warm interval occurred, being known as

1462-540: The numerous teleost fishes, which in turn evolved into new advanced and modern forms ( Neoteleostei ). Ichthyosaurs and pliosaurs , on the other hand, became extinct during the Cenomanian-Turonian anoxic event . Near the end of the Cretaceous Period, flowering plants diversified. In temperate regions, familiar plants like magnolias , sassafras , roses , redwoods , and willows could be found in abundance. The Cretaceous–Paleogene extinction event

1505-611: The old classical Tertiary and Quaternary, a compromise that was rejected by International Union of Geological Sciences because it split both Neogene and Pliocene in two. Following formal discussions at the 2008 International Geological Congress in Oslo, Norway, the ICS decided in May 2009 to make the Quaternary the youngest period of the Cenozoic Era with its base at 2.58 Mya and including

1548-503: The older definition of the beginning of the Quaternary Period; many time scales show this division. However, there was a movement amongst geologists (particularly marine geologists ) to also include ongoing geological time (Quaternary) in the Neogene, while others (particularly terrestrial geologists) insist the Quaternary to be a separate period of distinctly different record. The somewhat confusing terminology and disagreement amongst geologists on where to draw what hierarchical boundaries

1591-407: The open sea. Though primarily represented by azhdarchids , other forms like pteranodontids , tapejarids ( Caiuajara and Bakonydraco ), nyctosaurids and uncertain forms ( Piksi , Navajodactylus ) are also present. Historically, it has been assumed that pterosaurs were in decline due to competition with birds, but it appears that neither group overlapped significantly ecologically, nor

1634-628: The periods are more closely comparable to the duration of periods in the Mesozoic and Paleozoic Eras. The International Commission on Stratigraphy (ICS) once proposed that the Quaternary be considered a sub-era (sub-erathem) of the Neogene, with a beginning date of 2.58 Ma, namely the start of the Gelasian Stage . In the 2004 proposal of the ICS, the Neogene would have consisted of the Miocene and Pliocene Epochs. The International Union for Quaternary Research (INQUA) counterproposed that

1677-501: The reptilian genera Langstonia and Barinasuchus , terrestrial predators that were the last surviving members of Sebecosuchia , a group related to crocodiles. The oceans were dominated by large carnivores like megalodons and livyatans , and 19 million years ago about 70% of all pelagic shark species disappeared. Mammals and birds continued to be the dominant terrestrial vertebrates, and took many forms as they adapted to various habitats. An explosive radiation of ursids took place at

1720-622: The rocks deposited during the Neogene Period . The continents in the Neogene were very close to their current positions. The Isthmus of Panama formed, connecting North and South America . The Indian subcontinent continued to collide with Asia , forming the Himalayas . Sea levels fell, creating land bridges between Africa and Eurasia and between Eurasia and North America. The global climate became more seasonal and continued an overall drying and cooling trend which began during

1763-433: The very end of the epoch; the same can be said for true marsupials . Instead, nearly all known eutherian and metatherian fossils belong to other groups. In the seas, mosasaurs suddenly appeared and underwent a spectacular evolutionary radiation. Modern sharks also appeared and penguin-like polycotylid plesiosaurs (3 meters long) and huge long-necked elasmosaurs (13 meters long) also diversified. These predators fed on

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1806-537: Was a large-scale mass extinction of animal and plant species in a geologically short period of time, approximately 66  million years ago (Ma). It is widely known as the K–T extinction event and is associated with a geological signature, usually a thin band dated to that time and found in various parts of the world, known as the Cretaceous–Paleogene boundary (K–T boundary). K is the traditional abbreviation for

1849-405: Was an island chain. Populating some of these islands were endemic dwarf dinosaur species. In the Late Cretaceous, the hadrosaurs , ankylosaurs , and ceratopsians experienced success in Asiamerica (Western North America and eastern Asia). Tyrannosaurs dominated the large predator niche in North America. They were also present in Asia, although were usually smaller and more primitive than

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