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45-576: On the surface, the Pekin Formation is exposed only as a long, narrow strip along the western edge of the Sanford Sub-basin. It is both the oldest and stratigraphically lowest formation in the sub-basin. As such, it unconformably overlies the much older eroded and metamorphosed Proterozoic to Cambrian aged metasediments and metavolcanic rocks of the Piedmont . The upper boundary grades into

90-557: A crayfish -like decapod . Vertebrate remains are more common in the Pomona pit, which has preserved the fragmentary remains of archosaurs, phytosaurs, and synapsids, as well as fish bones and scales. Fossil footprints and trackways of tetrapods have also been recorded from the Pomona pit (with a single print from the Boren pit), including bipedal three-toed footprints that may have been made by early dinosaurs . Only vertebrate fossils are known from

135-399: A hiatus because deposition was on hold for a period of time. A physical gap may represent both a period of non-deposition and a period of erosion. A geologic fault may cause the appearance of a hiatus. Magnetostratigraphy is a chronostratigraphic technique used to date sedimentary and volcanic sequences. The method works by collecting oriented samples at measured intervals throughout

180-637: A broadly similar three-part stratigraphy, geologists have not been able to accurately correlate those of the Sanford Sub-basin with the other sub-basins due to variations in stratigraphy, lithology and biostratigraphy . Furthermore, the Pekin has a very similar lithology to the Sandford Formation, and are only distinguishable by the presence of the Cumnock Formation between them. As such, the Pekin, Cumnock and Sanford formations have been restricted to just

225-578: A decade until the NCMNS reached out in 2016, prompting negotiations to purchase the fossil. Legal issues concerning mineral rights significantly slowed these negotiations until they were resolved in 2020. Funds for the purchase were raised by the nonprofit Friends of the North Carolina Museum of Natural Sciences. Following the construction of a dedicated display wing in the Nature Research Center,

270-568: A dinosaur replica along with other items were stolen from NCMNS by two accomplices. The offenders turned themselves in on July 17. The replica, along with the other items were recovered. In 2020, the museum announced its acquisition of the Dueling Dinosaurs , a well-preserved and scientifically important specimen from Montana of a Triceratops and Tyrannosaurus possibly locked in combat. First found in 2006, there were unsuccessful attempts to sell it to museums or private collectors for over

315-450: A geological region, and then to every region, and by extension to provide an entire geologic record of the Earth. A gap or missing strata in the geological record of an area is called a stratigraphic hiatus. This may be the result of a halt in the deposition of sediment. Alternatively, the gap may be due to removal by erosion, in which case it may be called a stratigraphic vacuity. It is called

360-402: A lithostratigraphy or lithologic stratigraphy of the rock unit. Key concepts in stratigraphy involve understanding how certain geometric relationships between rock layers arise and what these geometries imply about their original depositional environment. The basic concept in stratigraphy, called the law of superposition , states: in an undeformed stratigraphic sequence, the oldest strata occur at

405-553: A relative scale until the development of radiometric dating , which was based on an absolute time framework, leading to the development of chronostratigraphy. One important development is the Vail curve , which attempts to define a global historical sea-level curve according to inferences from worldwide stratigraphic patterns. Stratigraphy is also commonly used to delineate the nature and extent of hydrocarbon -bearing reservoir rocks, seals, and traps of petroleum geology . Chronostratigraphy

450-436: A section. The samples are analyzed to determine their detrital remanent magnetism (DRM), that is, the polarity of Earth's magnetic field at the time a stratum was deposited. For sedimentary rocks this is possible because, as they fall through the water column, very fine-grained magnetic minerals (< 17  μm ) behave like tiny compasses , orienting themselves with Earth's magnetic field . Upon burial, that orientation

495-408: A skeleton". A typothoracisine aetosaur . Gorgetosuchus G. pekinensis NCPALEO 1902 10 articulated rows of osteoderms from the front half of the animal. A desmatosuchine aetosaur. Unique among aetosaurs for having spines on both its dorsal and lateral osteoderms around the neck. Longosuchus Stratigraphically Stratigraphy is a branch of geology concerned with

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540-408: A source in the highlands to the southeast, with rivers and streams in the upper Pekin flowing towards the north and northwest. The overall climate is interpreted as being warm and humid with highly seasonal rainfall. Clays from the Pekin Formation have been used extensively for the production of pottery , bricks and tiles , namely the Boren and Pomona pits. These two quarries have historically been

585-802: Is a satellite facility of the North Carolina Museum of Natural Sciences located in Greenville, North Carolina. It and the Grifton Nature and Science Center were acquired through a partnership between NCMNS and ATFS. The center was renovated with new exhibits being added and reopened in September 2021. The Museum at Greenville is largely based on the Raleigh facility, but with more exhibits focusing on subjects relevant to northeastern North Carolina such as pirates and pollinators , and includes resources from East Carolina University . NCMNS hosts many special events through

630-440: Is a satellite facility of the North Carolina Museum of Natural Sciences. Its mission is to celebrate the natural history and cultural heritage of North Carolina's forests through interpretive exhibits, educational programming, and the preservation of natural and man-made materials that demonstrate the ongoing relationship of forests and people. Displays and interactive exhibits include an outdoor Tree Trail and Fossil Dig Pit, and

675-432: Is part of the museum's mission of enhancing public understanding and appreciation of the natural environment by providing an outdoor learning space while acting as a model for renewable and sustainable energy . The facility opened a Nature PlaySpace on Saturday, September 28, 2013. The North Carolina Museum of Natural Sciences at Whiteville, North Carolina formerly known as the North Carolina Museum of Forestry,

720-411: Is preserved. For volcanic rocks, magnetic minerals, which form in the melt, orient themselves with the ambient magnetic field, and are fixed in place upon crystallization of the lava. Oriented paleomagnetic core samples are collected in the field; mudstones , siltstones , and very fine-grained sandstones are the preferred lithologies because the magnetic grains are finer and more likely to orient with

765-413: Is the branch of stratigraphy that places an absolute age, rather than a relative age on rock strata . The branch is concerned with deriving geochronological data for rock units, both directly and inferentially, so that a sequence of time-relative events that created the rocks formation can be derived. The ultimate aim of chronostratigraphy is to place dates on the sequence of deposition of all rocks within

810-668: The Dueling Dinosaurs exhibit was officially opened to the public in 2024 in the newly-built SECU DinoLab. The Center is located on Jones Street in downtown Raleigh. The Nature Research Center (NRC) is an 80,000 sq ft (7,400 m ), four-story wing across the street from the Nature Exploration Center. The NRC and NEC are connected by a breezeway. The initial opening (April 20, 2012) lasted for 24 hours and drew 70,000 visitors. The NRC provides hands-on activities and visitor-viewing of scientists working in

855-579: The North Carolina Museum of Natural Sciences list tooth fragments of " Archosaurus " sp. and Uatchitodon kroehleri , as well as a humerus fragment of " Rhynchosaurus " sp. Archosaurus and Rhynchosaurus are likely only provisional labels. Apatopus A. lineatus Pomona pit Trackways and isolated prints. Phytosaur footprints. Phytosauria indet. Indeterminate NCPALEO1902 Currently undescribed. ? Rutiodon ? R. carolinensis Rostrum fragment Originally misidentified as

900-421: The law of superposition , the principle of original horizontality and the principle of lateral continuity in a 1669 work on the fossilization of organic remains in layers of sediment. The first practical large-scale application of stratigraphy was by William Smith in the 1790s and early 19th century. Known as the "Father of English geology", Smith recognized the significance of strata or rock layering and

945-547: The natural remanent magnetization (NRM) to reveal the DRM. Following statistical analysis, the results are used to generate a local magnetostratigraphic column that can then be compared against the Global Magnetic Polarity Time Scale. This technique is used to date sequences that generally lack fossils or interbedded igneous rocks. The continuous nature of the sampling means that it is also a powerful technique for

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990-797: The sacrum of a large fossil bird and named " Palaeonornis struthionoides ". cf. Brachychirotherium cf. Brachychirotherium isp. Pomona pit Numerous isolated tracks. Tracks similar to Brachychirotherium , but differ in having a functionally tridactyl foot with reduced first digit and fifth digit positioned further back. Lack unequivocal hand impressions. Crocodylomorpha indet. Indeterminate NCPALEO 1902 A nearly complete articulated skeleton. A small-bodied basal crocodylomorph, currently undescribed. Carnufex C. carolinensis NCPALEO 1902 A partial skull and fragmentary postcranial skeleton. A large, possibly bipedal predatory crocodylomorph . Coahomasuchus C. chathamensis NCPALEO 1902 "Largely articulated, anterior portion of

1035-528: The NRC's four research laboratories. The museum also makes use of distance learning to broadcast lessons and virtual field trips to classrooms around the state. The Nature Research Center's three investigate labs are open-to-the-public hands-on educational spaces. The Nature Research Center's five research labs are part of the museum's Research and Collections department. These spaces (normally used for behind-the-scenes work) have transparent glass walls through which

1080-581: The North Carolina Museum of Natural Sciences at Greenville, was announced in 2020 and opened to the public on September 18, 2021. NCMNS is a division of the state Department of Natural and Cultural Resources . The North Carolina State Museum was created in 1879 by combining two existing state-owned collections of geologic and agricultural specimens. The museum was originally housed in the Briggs Building on Fayetteville Street . The museum's collections, outreach and education programs, and status grew over

1125-570: The Pekin Formation is equivalent to and is synonymous with the Stockton Formation. The Pekin Formation could then be considered an informal name for the Stockton Formation exposed in the Sanford Sub-basin. The base of the formation is composed of a roughly 10 metres (33 ft) thick layer of grey conglomerate , historically referred to as " millstone grit". This unit has been interpreted as alluvial fan deposits made up of material derived from

1170-514: The Pekin Formation spanned the entirety of the lower Deep River Basin, encompassing the lowest sedimentary units of the neighbouring Durham and the Wadesboro sub-basins. In fact, the Pekin Formation was named after the village of Pekin located in the Wadesboro Sub-basin, as this was where Campbell and Kimball (1923) considered it to be best exposed. However, although the three sub-basins share

1215-454: The Piedmont to the west flowing down in a southeasterly direction. The remainder of the Pekin Formation is made up of red to brown and purple sandstones , siltstones and mudstones , along with deposits of conglomerate and shale that altogether support a fluvial and floodplain deposition environment. Unlike the lowest layers, sedimentation for the rest of the Pekin Formation had switched to

1260-642: The Sanford Sub-basin where they can be recognised. In 2016, Robert E. Weems, Lawrence H. Tanner, and Spencer G. Lucas proposed that the Pekin Formation should be subsumed into the Stockton Formation . Rather than dividing the Newark Supergroup into numerous distinct formations localised in single basins, they proposed a system where the disparate formations of local basins were merged into fewer regional-scale formations, based upon overall similar lithologies, biostratigraphy and chronology. Under this scheme,

1305-588: The ambient field during deposition. If the ancient magnetic field were oriented similar to today's field ( North Magnetic Pole near the North Rotational Pole ), the strata would retain a normal polarity. If the data indicate that the North Magnetic Pole were near the South Rotational Pole , the strata would exhibit reversed polarity. Results of the individual samples are analyzed by removing

1350-407: The base of the sequence. Chemostratigraphy studies the changes in the relative proportions of trace elements and isotopes within and between lithologic units. Carbon and oxygen isotope ratios vary with time, and researchers can use those to map subtle changes that occurred in the paleoenvironment. This has led to the specialized field of isotopic stratigraphy. Cyclostratigraphy documents

1395-546: The estimation of sediment-accumulation rates. North Carolina Museum of Natural Sciences The North Carolina Museum of Natural Sciences ( NCMNS ) is a natural history museum in Raleigh, North Carolina . The museum is the oldest in the state, and the largest natural history museum in the Southeastern United States . The museum is made up of six facilities, divided between five campuses. The newest facility,

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1440-591: The importance of fossil markers for correlating strata; he created the first geologic map of England. Other influential applications of stratigraphy in the early 19th century were by Georges Cuvier and Alexandre Brongniart , who studied the geology of the region around Paris. Variation in rock units, most obviously displayed as visible layering, is due to physical contrasts in rock type ( lithology ). This variation can occur vertically as layering (bedding), or laterally, and reflects changes in environments of deposition (known as facies change). These variations provide

1485-473: The most notable finds include an intact specimen of the early palm -like cycad Leptocycas gracilis , as well as a new species of the bennettitale Williamsonia , W. carolinensis , that preserves rare reproductive organs and suggests that it and the leaf Eoginkgoites belong to the same plant. Invertebrate fossils from the Boren pits include conchostracans (clam shrimps) and clams , as well as numerous Scoyenia burrow trace fossils likely made by

1530-581: The museum offers educational program experiences and special events. The North Carolina Museum of Natural Sciences at Contentnea Creek , formerly known as the Grifton Nature & Science Center, is a satellite facility and outdoor classroom located in Grifton, North Carolina . It features hiking and paddling trails centered around Contentnea Creek, along with an observatory and outdoor classroom. The North Carolina Museum of Natural Sciences at Greenville, North Carolina formerly known as A Time For Science (ATFS),

1575-456: The next 60 years under the stewardship of Herbert Brimley . In 1887 the museum was placed under the management of the Department of Agriculture , and was moved to the department's office building: a former hotel on Edenton Street across from the capitol building. An annex was added in 1899 as the collection grew, and the entire facility was moved to a purpose-built building in 1924. The facility

1620-478: The often cyclic changes in the relative proportions of minerals (particularly carbonates ), grain size, thickness of sediment layers ( varves ) and fossil diversity with time, related to seasonal or longer term changes in palaeoclimates . Biostratigraphy or paleontologic stratigraphy is based on fossil evidence in the rock layers. Strata from widespread locations containing the same fossil fauna and flora are said to be correlatable in time. Biologic stratigraphy

1665-527: The overlying Cumnock Formation , distinguished by its fine-grained grey lacustrine sediments. The Pekin Formation was deposited in a half-graben that formed as part of a series of rift basins that make up the Newark Supergroup during the breakup of the supercontinent Pangaea and subsequent opening of the Atlantic Ocean . As originally defined by Marius R. Campbell and Kent W. Kimball in 1923,

1710-489: The public can observe research scientists. The atrium is home to the LCD sculpture Patterned by Nature . Prairie Ridge Ecostation (45 acres (180,000 m )) is a satellite facility and outdoor classroom located 6 miles (9.7 km) from the museum's downtown Raleigh locations. It includes Piedmont prairie , forest, ponds, a stream, and sustainable building features integrated with a wildlife-friendly landscape. Prairie Ridge

1755-628: The relatively complete remains of new Triassic archosaurs . The age of the Pekin Formation has been estimated based on biostratigraphy and magnetostratigraphy to the Late Carnian (or Tuvalian), supported by correlations with faunas in western North America. A variety of plant and vertebrate fossils have been recovered from the Pekin Formation, the including partial skeletons of large vertebrates. The Boren pits preserves abundant plant megafossils , most commonly cycads and bennettitales , as well as horsetails , various ferns and conifers . Some of

1800-451: The site of fossil discoveries, preserving both plants and animals, as well as trace fossils , although these quarries are now disused and some have filled with water. However, excavations by palaeontologists have been continued in a new brick quarry (Merry Oaks Quarry) by the North Carolina Museum of Natural Sciences (NCMNS) at a site labelled NCPALEO 1902. These excavations have uncovered various new vertebrate fossil discoveries, including

1845-434: The study of rock layers ( strata ) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks . Stratigraphy has three related subfields: lithostratigraphy (lithologic stratigraphy), biostratigraphy (biologic stratigraphy), and chronostratigraphy (stratigraphy by age). Catholic priest Nicholas Steno established the theoretical basis for stratigraphy when he introduced

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1890-521: The upper Pekin NCPALEO 1902 locality, and include a variety of archosaurs and synapsids typical of Late Triassic North America. The vertebrate fauna of the Pekin Formation has been used to correlate it with strata in western North America, such as the Chinle Formation , with some genera (e.g. Placerias , Coahomasuchus ) being shared between eastern and western North America. The online collections of

1935-419: Was based on William Smith's principle of faunal succession , which predated, and was one of the first and most powerful lines of evidence for, biological evolution . It provides strong evidence for the formation ( speciation ) and extinction of species . The geologic time scale was developed during the 19th century, based on the evidence of biologic stratigraphy and faunal succession. This timescale remained

1980-693: Was later overhauled and reopened in 2015 as the NC Museum of Natural Sciences in Whiteville. Another location was added in 2004, with the opening of the Prairie Ridge Ecostation for Wildlife and Learning. The museum expanded its downtown campus in 2012 with the adjacent Nature Research Center. The collection contains over 1.7 million specimens, including amphibians , reptiles , birds, fish, mammals, invertebrates , invertebrate and vertebrate fossils, plants, geology , and meteorites . On July 14, 2014,

2025-590: Was later renamed the North Carolina State Museum of Natural History. In the 1950s and again in the 1990s, shifts in education further expanded the museum's holdings as universities donated their collections to the state. In 1986, the museum was renamed to The North Carolina State Museum of Natural Sciences. In 2000, the museum expanded with the opening of the Museum of Forestry in Whiteville . This facility

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