Paja Formation

{{short description|Early Cretaceous geologic formation of central Colombia}}

{{Infobox rockunit

| name = Paja Formation

| image = Desmatochelys padillai Colombia.jpg

| caption = Desmatochelys padillai from the Paja Formation

| age = Late Hauterivian-Late Aptian
~{{fossil range|130|113}}

| period = Aptian

| type = Geological formation

| subunits = Lutitas Negras Inferiores, Arcillolitas Abigarradas & Arcillolitas con Nódulos Huecos Members

| underlies = San Gil Group, Simití & Tablazo Formations

| overlies = Ritoque & Rosablanca Formations

| prilithology = Black shale, claystone, sandstone and limestone concretions

| otherlithology = Gypsum, chalcopyrite, galena, malachite, pyrite, sphalerite

| thickness = up to {{convert|940|m|ft|abbr=on}}

| namedfor = Quebrada La Paja

| namedby = Wheeler

| year_ts = 1929?

| region = Bolívar, Boyacá, Cundinamarca & Santander

| country = Colombia

| extent = Altiplano Cundiboyacense
Eastern Ranges, Andes
Middle Magdalena Valley

| area = {{convert|450|km|mi|abbr=on}}

| coordinates = {{coord|5.5|N|73.5|W|region:CO|display=inline,title}}

| paleocoordinates = {{coord|3.7|N|42.2|W|display=inline}}

| coordinates_ts = {{coord|7|01|33.4|N|73|19|27.8|W|display=inline}}

| paleocoordinates_ts =

| region_ts = Betulia, Santander

| thickness_ts = {{convert|625|m|ft|abbr=on}}

| map = Geologic map - outcrops of the Paja Formation and Ritoque Formation, Villa de Leyva, Colombia.jpg

| map_caption = Outcrops of the Paja Formation near Villa de Leyva

}}

The Paja Formation ({{langx|es|Formación Paja}}, K1p, Kip, Kimp, b3b6p) is an Early Cretaceous geologic formation of central Colombia. The formation extends across the northern part of the Altiplano Cundiboyacense, the Western Colombian emerald belt and surrounding areas of the Eastern Ranges of the Colombian Andes. In the subsurface, the formation is found in the Middle Magdalena Valley to the west. The Paja Formation stretches across four departments, from north to south the southernmost Bolívar Department, in Santander, Boyacá and the northern part of Cundinamarca. Well known fossiliferous outcrops of the formation occur near Villa de Leyva, also written as Villa de Leiva, and neighboring Sáchica.

The formation was named after Quebrada La Paja in Betulia, Santander, and stretches across {{convert|450|km|mi}} from northeast to southwest. The Paja Formation overlies the Ritoque and Rosablanca Formations and is overlain by the San Gil Group and the Simití and Tablazo Formations and dates from the late Hauterivian to late Aptian. The Paja Formation comprises mudstones, shales and nodules of sandstones and limestones, deposited in an anoxic environment, in the warm and shallow sea that covered large parts of the present Colombian territory during the Cretaceous.

Initially considered to host Colombian emeralds, the emerald-bearing part was redefined as a separate formation; the Muzo Formation. The Paja Formation Lagerstätte is famous for its vertebrate fossils and is the richest Mesozoic fossiliferous formation of Colombia. Several marine reptile fossils of plesiosaurs, pliosaurs, ichthyosaurs and turtles have been described from the formation and it hosts the only dinosaur fossils described in the country to date; Padillasaurus. The formation also has provided many ammonites, fossil flora, decapods and the fossil shark Protolamna ricaurtei.

Description

The Paja Formation was first described by O.C. Wheeler, according to Morales (1958),Morales, 1958 and named after Quebrada La Paja, a tributary of the Sogamoso River. The type section is exposed on the northern banks of the quebrada at the confluence of the Sogamoso River in Betulia, Santander.Reyes et al., 2006, p.33Plancha 120, 2010

The formation is divided into the Lutitas Negras Inferiores, Arcillolitas Abigarradas and Arcillolitas con Nódulos Huecos Members, and stretches across {{convert|450|km|mi}} from northeast to southwest. The Paja Formation overlies the Ritoque and Rosablanca Formations and is overlain by the Simití and Tablazo Formations and dates from the Hauterivian to Late Aptian.

= Outcrops =

{{Location map | Colombia Santander Department

| relief = 1

| width = 250

| lat_deg = 7.025953

| lon_deg = -73.324385

| float = right

| mark = Green pog.svg

| marksize = 12

| caption = Type locality of the Paja Formation in Santander

}}

The type section of the Paja Formation is found at the banks of Quebrada La Paja in Betulia, Santander, where the formation has a thickness of {{convert|625|m|ft}}.Patarroyo & Moreno, 1997, p.30 Outcrops of the formation extend from Simití in the north, close to the border of Santander and Bolívar, where the formation is offset by the Simití Fault,Plancha 85, 2006 to the Pauna Anticlinal in San Pablo de Borbur, where the formation is thrusted over the Ritoque Formation in the south.Plancha 190, 1998 In the southern extension of the exposures, the formation crops out in the north of Tununguá, near the Ibacapí Fault.Reyes et al., 2006, p.32

;Santander

In the Middle Magdalena Valley, south of Barrancabermeja, the Paja Formation in the subsurface is offset by the Casabe, Infantas and Arruga Faults.Plancha 119, 2008 In the northeastern extent, in Río Negro, near the border with Norte de Santander, the formation is found in the subsurface, offset by the Lebríja Fault.Plancha 97, 2009 The town center of Zapatoca rests on the formation in the synclinal named after the village. The Paja Formation also crops out in the northwestern part of the Middle Magdalena Valley, east of San Pablo, Bolívar, where in the formation underlies the Simití Formation and is offset in the subsurface by the Pozo Azul and Caña Braval Faults.Plancha 96, 2006 South of there, the Paja Formation is offset by the La Corcovada and El Guineal Faults,Plancha 149, 2008 and the regional La Salina Fault.Plancha 134, 2008 Near the eponymous town, the formation is offset by the Landazurí Fault.Plancha 150, 2008

West of Barichara, the formation underlies the corregimiento {{ill|Guane, Barichara|es|Guane (Santander)}} and is found in the hills bordering both sides of the Suárez River. In this area, the Paja Formation is offset by the Suárez Fault.Royero & Clavijo, 2001, p.53 Surrounding Jordán, Santander, the formation crops out on both sides of the Chicamocha River in the Chicamocha Canyon. The touristic town San Gil rests on the formation and the Fonce River cuts into it. East of the town center, the formation is offset by the Curití and Ocamonte Faults.Plancha 135, 2009 The urban centers of Oiba, San Benito, Encino, Ocamonte and Charalá are built on top of the Paja Formation. In this area, the formation is offset by the Confines and Encino Faults.Plancha 151, 2009 Further to the south, the towns of Vélez, Guavatá and Jesús María rest on the formation. West of the latter, the Paja Formation is put in a reverse faulted contact with the Cumbre Formation.Plancha 170, 2009 The El Carmen Fault puts the Paja Formation in contact with the Jurassic Girón Formation.

;Boyacá

{{Location map+ | Altiplano Cundiboyacense

| AlternativeMap = Altiplano Cundiboyacense (subdivisions).png

| width = 250

| float = left

| caption = Fossiliferous outcrops near Villa de Leyva on the Altiplano Cundiboyacense

| places =

{{Location map~ | Altiplano Cundiboyacense

| lat_deg = 5.641502

| lon_deg = -73.563959

| mark = Green pog.svg

| marksize = 12

}}

In northeastern Boyacá, the formation underlies the urban center of Moniquirá (not to be confused with Monquirá, a vereda of nearby Villa de Leyva) and is crossed by the Moniquirá River. West of Arcabuco in the Villa de Leyva Synclinal, the formation is cut by the Arcabuco River.Plancha 171, 2009 In the vicinity of Pauna and San Pablo de Borbur, the formation crops out in an extensive area. Here, the Paja Formation is offset by the Río Minero and Pedro Gómez Faults and occurs in the footwall of the La Venta Fault.Reyes et al., 2006, p.83 North of Lake Fúquene, the town centers of Tinjacá and Sutamarchán are built on top of the Paja Formation. In this area, the formation extends into the northern part of Cundinamarca, where the urban centers of Yacopí and La Palma rest on the formation.Plancha 189, 2005

= Villa de Leyva =

Surrounding the touristic town of Villa de Leyva, the formation crops out in the hills in a microclimatic location, known as the La Candelaria Desert ({{langx|es|Desierto de La Candelaria}}), stretching across Villa de Leyva, Santa Sofía and Sáchica.Plancha 191, 1998 Along the highway Tunja-Villa de Leyva, the formation is heavily folded and faulted along a stretch of {{convert|500|m|ft}}.Moreno & Hincapié, 2010, p.44 In the vicinity of Villa de Leyva, the formation has provided many fossils of marine reptiles, as well as the dinosaur Padillasaurus.

= Stratigraphy =

File:Paja Formation - stratigraphic column and Sachicasaurus site.jpg

The Paja Formation overlies the Ritoque and Rosablanca Formations and is concordantly overlain by the San Gil Group and Tablazo Formations in the eastern extent,Royero & Clavijo, 2001, p.31 and the Simití Formation in the northwestern Middle Magdalena Valley. In the Western emerald belt, the contact with the Rosablanca Formation is concordant and abrupt.Reyes et al., 2006, p.26 The total thickness of the formation varies across its extent, but can reach up to {{convert|940|m|ft}}.Moreno & Hincapié, 2010, p.26

;Members

The Paja Formation is subdivided into three members, from oldest to youngest:

Lutitas Negras Inferiores (Lower Black Shales) – a sequence of {{convert|340|m|ft}} of black shales and sandy shales with a segment containing calcareous nodules. The age of this member is estimated at late Hauterivian, based on ammonites analyzed by Fernando Etayo.Moreno & Hincapié, 2010, p.25
Arcillolitas Abigarradas (Mottled Claystones) – a series of multicolored claystones with abundant calcareous fossiliferous nodules, reaching a thickness of {{convert|480|m|ft}}. In the upper {{convert|235|m|ft}} of this member, intercalations of gypsum occur. The age of the middle member of the Paja Formation is estimated at early Barremian to late Aptian on the basis of ammonites described by Fernando Etayo.
Arcillolitas con Nódulos Huecos (Claystones with Hollow Nodules) – the upper member of the formation of approximately {{convert|174|m|ft}} thick consists of yellowish and grey claystones containing hollow nodules. Ammonite analysis has led to an estimated late Aptian age for the member.

In the northern part of the Middle Magdalena Valley, the Paja Formation comprises dark grey to blueish shales, intercalated with grey to yellowish fine-grained sandstones and fossiliferous limestones, locally with a sandy component.Sarmiento et al., 2015, p.65 Bürgl in 1954 reported beds of tuff in the Paja Formation near Villa de Leyva.Sarmiento Rojas, 2002, p.56 Thin section analysis of samples of the Paja Formation has provided insight in the micritic components of the sediments, where three microfacies were recognized; biomicritic wackestones, foraminiferous packstones and sandy biomicritic floatstones containing fragments of echinoderms, bivalves, crinoids and gastropods cemented by hematite.Espinel & Hurtado, 2010, p.70

The Paja Formation correlates with the Tibasosa Formation to the east on the northern Altiplano Cundiboyacense in Boyacá and with the El Peñón Formation pertaining to the Villeta Group to the south in the Eastern Ranges. The formation is laterally equivalent with the black shales of the Fómeque Formation in the eastern part of the Eastern Ranges and the sandstones of Las Juntas Formation in the Sierra Nevada del Cocuy.Villamil, 2012, p.168 In the Middle Magdalena Valley to the west, the formation partly overlies and partly is laterally equivalent to the limestones of the Rosablanca Formation. The Paja Formation is diachronous with the Ritoque and Rosablanca Formations. To the northeast of the extent of the formation, it correlates with the upper part of the Río Negro Formation,Royero & Clavijo, 2001, p.29 and the lowermost Tibú-Mercedes Formation of the Catatumbo Basin.Royero & Clavijo, 2001, p.32

Paleogeography

File:Paleogeography of northern South America - Barremian-Aptian - 120Ma.jpg

{{see also|Altiplano Cundiboyacense#Geology|Eastern Hills, Bogotá#Geology}}

During deposition of the Paja Formation, the paleo coastline was oriented west–east.Rivera et al., 2018, p.30

From the late Aptian to early Albian, the area was covered by an extensive carbonate platform, in the extent of the Paja Formation represented by the San Gil Group, Tablazo Formation and Villeta Group.Villamil, 2012, p.164

= Depositional environment =

The thin section analysis led to the interpretation of a shoreface to lower shoreface environment,Gaona Narváez et al., 2013 in the internal parts of a carbonate platform,Espinel & Hurtado, 2010, p.73Espinel & Hurtado, 2010, p.89 where transgressions and regressions caused the variations in grain sizes and lithologies.Galvis & Valencia, 2009, p.79 The Barremian to Aptian sequence shows evidence of an overall relative sea level fall with open marine sedimentation in the lowest member and tidal deposits in the upper part of the formation.Galvis & Valencia, 2009, p.81

One of the longest anoxic intervals of geologic history occurred during the Cretaceous, from about 125 to 80 Ma (early Aptian to early Campanian). During this Oceanic Anoxic Event, there were two spikes, the Selli event, dating to the early Aptian (approximately 120 Ma) was active during deposition of the black shales of the Paja Formation.Moreno & Hincapié, 2010, p.48 The formation contains three spikes of δ¹³C, with values above 1.5‰, in the lower, middle to upper and upper Paja Formation.Moreno & Hincapié, 2010, p.63 These spikes indicate a global change in the carbon cycle and the preservation of organic matter due to poor oxygenation of sea waters. The cause of these elevated δ¹³C levels may have been a global increase in volcanic activity.Moreno & Hincapié, 2010, p.64

Mining and petroleum geology

The Paja Formation is one of the stratigraphic units cropping out in the Western emerald belt.Reyes et al., 2006, p.82 Mineralization in the formation has been dated on the basis of ⁴⁰Ar/³⁹Ar analysis of muscovite minerals. In western San Pablo de Borbur, Boyacá, the mineralization dates to the Late Eocene at 36.4 ± 0.1 and 37.3 ± 0.1 Ma.Gómez Tapias et al., 2015, p.214 In the northwestern part of Muzo, Boyacá, mineralization happened during the Early Oligocene, at 31.4 ± 0.3 Ma.Gómez Tapias et al., 2015, p.208 Previous geologic researchers considered the Paja Formation hosted emeralds, and later definition of the stratigraphy of Colombia separated one of the main emerald formations of Colombia as the contemporaneous Barremian Muzo Formation, providing emeralds in the La Pita mine and important Coscuéz mine.Reyes et al., 2006, p.106

The Paja Formation is known for its gypsum deposits, which are mined and restricted to Santander.Royero & Clavijo, 2001, p.60 Near Guavatá, the formation hosts sphalerite and malachite and near Otanche, pyrite and galena are found in the formation.Sarmiento Rojas, 2002, p.65 In Gámbita, the Paja Formation contains pyrite, galena and chalcopyrite.Sarmiento Rojas, 2002, p.66 Other minerals occurring in the Paja Formation, are lead and zinc, around Paime and Yacopí, Cundinamarca.Acosta & Ulloa, 2002, p.75

The Paja Formation is considered a minor source rock in the Eastern Cordillera Basin and the Middle Magdalena Valley, with seal capacity for the underlying Rosablanca Formation reservoir in the latter basin.Mojica et al., 2009, p.22Mojica et al., 2009, p.39 Vitrinite reflectance analysis on samples of the Paja Formation indicate an average value of 0.52 Ro, making the formation a marginal source rock.Moreno & Hincapié, 2010, p.74

Paleontological significance

File:Gondava Park - Villa de Leyva, Colombia.jpg

{{see also|List of fossiliferous stratigraphic units in Colombia}}

The Paja Formation is the richest Mesozoic fossiliferous formation of Colombia. Fauna of dinosaurs, Padillasaurus, and various marine reptiles, among which plesiosaurs, ichthyosaurs, pliosaurs and turtles make up the vertebrate assemblage. Furthermore, many ammonites, the foraminifer Epistomina,Patarroyo Camargo et al., 2009 decapods, flora and fossil fish have been recovered from the formation. Paja ammonites have been used in the walls and floor of the {{ill|Convento del Santo Ecce Homo|es|Convento del Santo Ecce Homo (Colombia)}} near Villa de Leyva.

In 2019, turtle expert Edwin Cadena described a fossil of Desmatochelys padillai who was found with her eggs still inside her.[https://www.urosario.edu.co/Home-V3/Investigacion/Divulgacion-cientifica-Ed-03-2019/Ciencia-y-Tecnologia/En-Colombia-encuentran-el-primer-fosil-de-una-tort/ En Colombia encuentran el primer fósil de una tortuga marina, ¡embarazada!] – Universidad del Rosario

Within the Arcillolitas Abigarradas Member of the Paja Formation, some horizons preserve abundant wood, which is frequently bored by pseudoplanktonic pholadoid bivalves, commonly referred to as "shipworms" or "piddocks". The presence of wood boring bivalves in Paja Formation seas indicates the continued presence of xylic substrates, and long residence time of floating wood.Noé et al., 2018

The paleontological richness of the formation led to the establishment of a center of investigation; {{ill|Centro de Investigaciones Paleontológicas|es}} (CIP),{{in lang|es}} [http://www.villadeleyvaweb.com/sitiosinteres/centro-investigaciones-paleontologicas Centro de Investigaciones Paleontológicas] two museums; {{ill|Paleontological Museum of Villa de Leyva|es|Museo Paleontológico de Villa de Leyva}},{{in lang|es}} [http://ciencias.bogota.unal.edu.co/paleontologico Museo Paleontológico de Villa de Leyva] and Museo El Fósil,{{in lang|es}} [http://envilladeleyva.com/ck15-hacer-y-comer/ck24-museos-y-atracciones/museo-el-fosil-monquira/ Museo El Fósil] and a dinosaur park; Gondava,{{in lang|es}} [http://www.granvalle.com/ Parque Gondava] near Villa de Leyva.

=IUGS geological heritage site=

In respect of the 'world's most complete record of Lower Cretaceous marine reptiles and associated fauna', the International Union of Geological Sciences (IUGS) included the 'Marine Reptile Lagerstätte from the Lower Cretaceous of the Ricaurte Alto' in its assemblage of 100 'geological heritage sites' around the world in a listing published in October 2022. The organisation defines an IUGS Geological Heritage Site as 'a key place with geological elements and/or processes of international scientific relevance, used as a reference, and/or with a substantial contribution to the development of geological sciences through history.'{{cite web |title=The First 100 IUGS Geological Heritage Sites |url=https://iugs-geoheritage.org/videos-pdfs/iugs_first_100_book_v2.pdf |website=IUGS International Commission on Geoheritage |publisher=IUGS |access-date=13 November 2022}}

= Fossil content =

== Reptiles ==

colspan="7" align="center" \| Reptiles of the Paja Formation
class="wikitable"
Genus	Species	Location	Member	Description	Notes	Image
Acostasaurus	A. pavachoquensis		Arcillolitas abigarradas	A pliosaurid with short snout, likely not a brachauchenine	{{center\|Gómez Pérez & Noè, 2017}}	File:Acostasaurus_pavachoquensis_by_duskyvel-dbys3fi.png
Callawayasaurus	C. colombiensis	Loma La Catalina	Arcillolitas abigarradas	An elasmosaurid plesiosaur, originally classified in Alzadasaurus	{{center\|Welles, 1962Carpenter, 1999}}	File:Callawayasaurus colombiensis.JPG
Desmatochelys	D. padillai	Loma de Monsalve Loma La Catalina	Arcillolitas abigarradas	A species of the genus Desmatochelys, sea turtles that belongs to the extinct family Protostegidae. Is the oldest known sea turtle, and a specimen was found with eggs still inside her.	{{center\|}}	File:Desmatochelys padillai.jpg
Monquirasaurus	M. boyacensis	Vereda Monquirá	Arcillolitas abigarradas	A large pliosaurid, initially named "Kronosaurus boyacensis"	{{center\|Acosta et al., 1979Hampe, 1992}}	File:Kronosaurus bojacens1DB.jpg
Leyvachelys	L. cipadi	Loma La Catalina	Arcillolitas abigarradas	A durophagous turtle member of the Sandownidae; is the first record for this group in South America. This species occurs too in the Glen Rose Formation in USA	{{center\|Cadena & Parham, 2015aCadena, 2015b}}	File:Leyvachelys cipadi - Paja Formation, Colombia.jpg
Leivanectes	L. bernadoi		Arcillolitas abigarradas	An elasmosaurid plesiosaur	{{center\|Páramo Fonseca et al., 2019}}
Muiscasaurus	M. catheti	Vereda Llanitos	Arcillolitas abigarradas	An ophthalmosaurid ichthyosaur, that it seems have occupied a different ecological niche respect to P. sachicarum	{{center\|Maxwell et al., 2015}}
Padillasaurus	P. leivaensis	La Tordolla	Arcillolitas abigarradas	A brachiosaurid dinosaur, that makes the first record of a terrestrial animal in the area, and the first Cretaceous brachiosaurid known outside from North America	{{center\|Carballido et al., 2015}}	File:FICHA 4 VERTEBRAS.gif
Platypterygius	P. elsuntuoso	Loma La Cabrera	Arcillotitas abigarradas	A platypterygiine ichthyosaur	{{center\|{{Cite journal \|last=Fonseca \|first=María Eurídice Páramo \|last2=Cabra \|first2=Cristian David Benavides \|last3=Camacho \|first3=Renzo Garavito \|date=2024-09-19 \|title=A new species of Platypterygius (Ophthalmosauridae) from the lower Barremian of Colombia and assessment of the species composition of the genus \|url=https://revistas.unal.edu.co/index.php/esrj/article/view/112332 \|journal=Earth Sciences Research Journal \|language=en \|volume=28 \|issue=2 \|pages=103–126 \|doi=10.15446/esrj.v28n2.112332 \|issn=2339-3459\|doi-access=free }}}}
Kyhytysuka	K. sachicarum	Sáchica	Arcillolitas abigarradas	A platypterygiine ichthyosaur, relative of P. americanum	{{center\|Páramo, 1997}}	File:Platypterygius sachicarum.jpg
Sachicasaurus	S. vitae	Sáchica	Arcillolitas abigarradas	A {{convert\|10\|m\|ft}} subadult pliosaur	{{center\|Páramo Fonseca et al., 2018, p.226}}	File:Sachicasaurus vitae - holotype - Paja Formation, Colombia.jpg
Stenorhynchosaurus	S. munozi	Loma La Cabrera	Arcillolitas abigarradas	A small pliosaurid, over 3 meters in length. Formerly considered as a close relative of Brachauchenius lucasi from North America	{{center\|Hampe, 2005Páramo et al., 2016}}
Teleosauroidea gen. indet.	species indet.		Arcillolitas abigarradas Mb.	Fossils of a member of Teleosauroidea with an estimated body length of 9.6 m, representing the most recent definitive record of Teleosauroidea reported	{{center\|Cortés et al., 2019}}

== Ammonites ==

File:Piso de fósiles del Convento del Santo Ecce Homo. Bopyacá.JPG

File:Centro de Investigaciones Paleontológicas - Villa de Leyva, Colombia.jpg

File:Ammonoid Fossil in Concretion - P9151650 (46048505111).jpg

File:Septarian Concretions - P9151651 (46048507001).jpg in the museum]]

Species	Images	Notes
class="wikitable" ! colspan=3 align=center \| Ammonites of the Paja Formation
Acanthoptychoceras trumpyi	File:Acanthoptychoceras trumpyi - Paja Formation, Colombia.jpg	align=center \| Patarroyo, 2009, p.19
Ancycloceras vandenheckii	rowspan=2 \| File:Ancyloceras vandenheckii velezianum (2) & Ancyloceras vandenheckii (3) - Paja Formation, Colombia.jpg	align=center \|
Ancycloceras vandenheckii velezianum	align=center \| Kabakadze & Hoedemaeker, 1997, p.67
Buergliceras buerglii	File:Buergliceras buerglii - Paja Formation, Colombia.jpg	align=center \| Etayo, 1968b, p.63
Colchidites breistrofferi	File:Colchidites breistrofferi - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.81
Crioceratites emerici	File:Crioceratites emerici - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.62
Crioceratites leivaensis	File:Crioceratites leivaensis - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.59
Crioceratites tener	File:Crioceratites tener - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.61
Hamiticeras chipatai	File:Hamiticeras chipatai - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.77
Hamiticeras pilsbryi	File:Hamiticeras pilsbryi - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.75
Hamulinites munieri	File:Hamulinites munieri - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.80
Karsteniceras beyrichi	File:Karsteniceras beyrichi - Paja Formation, Colombia.jpg	align=center \| Etayo, 1968b, p.54Kabakadze & Hoedemaeker, 1997, p.71
Karsteniceras multicostatum	File:Karsteniceras multicostatum - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.72
Monsalveiceras monsalvense	File:Monsalveiceras monsalvense - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.74
Nicklesia pulcella	File:Nicklesia pulcella - Paja Formation, Colombia.jpg	align=center \|
Pariacrioceras barremense	File:Paracrioceras barremense - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.66
Pedioceras asymmetricum	File:Pedioceras asymmetricum - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.64
Pedioceras caquesense	File:Pedioceras caquesense - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.63
Protanisoceras creutzbergi	File:Protanisoceras creutzbergi - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.82
Pseudoaustraliceras columbiae	File:Pseudoaustraliceras columbiae - Paja Formation, Colombia.jpg	align=center \|
Pseudoaustraliceras pavlowi	File:Pseudoaustraliceras pavlowi - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.69
Pseudoaustraliceras ramososeptatum	File:Pseudoaustraliceras ramososeptatum - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.70
Pseudocrioceras anthulai	File:Pseudocrioceras anthulai - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.68
Ptychoceras puzosianum	File:Ptychoceras puzosianum - Paja Formation, Colombia.jpg	align=center \|
Tonohamites koeneni	File:Tonohamites koeneni - Paja Formation, Colombia.jpg	align=center \| Kabakadze & Hoedemaeker, 1997, p.78
Criceratites sp.	File:Criceratites sp. - Paja Formation, Colombia.jpg	align=center \|
Pedioceras sp.	File:Pedioceras sp. - Paja Formation, Colombia.jpg	align=center \|
Acanthohoplites		align=center \| Gómez & Salgado, 2017, p.17
Acrioceras julivertii		align=center \| Etayo, 1968b, p.56
Colchidites apolinarii		align=center \| Etayo, 1968b, p.59
Crioceratites portarum		align=center \| Etayo, 1968b, p.57
Favrella colombiana		align=center \| Etayo, 1968b, p.62
Heinzia (Gerhardtia) veleziensis		align=center \| Patarroyo, 2000, p.154
Nicklesia didayana didayana		align=center \| Patarroyo, 1997, p.137
Nicklesia didayana multifida		align=center \|
Nicklesia dumasiana		align=center \|
Nicklesia nolani		align=center \|
Olcostephanus boussingaultii		align=center \| Etayo, 1968b, p.60
Parasaynoceras horridum		align=center \| Etayo, 1968b, p.64
Pseudohaploceras incertum		align=center \|
Psilotissotia colombiana		align=center \| Patarroyo, 2000, p.152
Pulchellia galeata		align=center \|
Dufrenoyia sp.		align=center \| Espinel & Hurtado, 2010, p.11
Valdedorsella sp.		align=center \|

== Crustaceans ==

colspan="3" align="center" \| Crustaceans of the Paja Formation
class="wikitable"
Species	Image	Notes
Bellcarcinus aptiensis	File:Bellcarcinus aptiensis - Paja Formation, Colombia.jpg	align=center \| Luque, 2014
Colombicarcinus laevis		align=center \| Karasawa et al., 2014
Notopocorystes kerri		align=center \| Luque et al., 2012, p.411
Planocarcinus olssoni		align=center \| Luque et al., 2012, p.408
Telamonocarcinus antiquus		align=center \| Luque, 2015

== Flora ==

colspan=3 align=center \| Flora of the Paja Formation
class="wikitable"
Species	Image	Notes
Frenelopsis cf. ramosissima	File:Frenelopsis cf. Ramosissima - Paja Formation, Colombia.jpg	align=center \| Moreno et al., 2007, p.18
Pseudofrenelopsis sp.	File:Pseudofrenelopsis sp. - Paja Formation, Colombia.jpg	align=center \| Moreno et al., 2007, p.15

== Fish ==

Protolamna ricaurteiCarrillo Briceño et al., 2019
Vinctifer sp.{{Cite journal |last1=Alfonso-Rojas |first1=Andrés |last2=Cadena |first2=Edwin-Alberto |date=2020-07-08 |title=Exceptionally preserved 'skin' in an Early Cretaceous fish from Colombia |journal=PeerJ |language=en |volume=8 |pages=e9479 |doi=10.7717/peerj.9479 |pmid=32714661 |pmc=7353916 |issn=2167-8359 |doi-access=free }}{{Cite journal |last=Hampe |first=Oliver |date=2005 |title=Considerations on aBrachauchenius skeleton (Pliosauroidea) from the lower Paja Formation (late Barremian) of Villa de Leyva area (Colombia) |url=http://www.foss-rec.net/8/37/2005 |journal=Mitteilungen aus dem Museum für Naturkunde in Berlin, Geowissenschaftliche Reihe |language=en |volume=8 |issue=1 |pages=37–51 |doi=10.1002/mmng.200410003 |issn=1435-1943|doi-access=free }}
Ichthyodectidae

== Ichnofossils ==

Teredolites clavatusChaparro et al., 2015

Regional correlations

{{Cretaceous stratigraphy of the central Colombian Eastern Ranges}}

= Panorama =

{{wide image|Panorama Chicamocha Canyon, Santander.jpg|1200px|align-cap=center|Panorama of the Chicamocha Canyon, from bottom to top; Jurassic Jordán and Girón Formations, and the Cretaceous Rosablanca and Paja Formations}}

Notes

References

= Bibliography =

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== Maps ==

{{citation |last1=Bernal Vargas |first1=Luis Enrique |last2=Mantilla Figueroa |first2=Luis Carlos |year=2006 |title=Plancha 85 – Simití – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QMzZHTS1Pa1pNb1k |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Bernal Vargas |first1=Luis Enrique |last2=Mantilla Figueroa |first2=Luis Carlos |year=2006 |title=Plancha 96 – Bocas del Rosario – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17Qd3VvbUUyV0lfTEE |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Vargas |first1=Rodrigo |last2=Arias |first2=Alfonso |year=2009 |title=Plancha 97 – Cáchira – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QV0ZuemdEREpzVE0 |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Beltrán |first1=Alejandro |last2=Quintero |first2=Claudia I. |year=2008 |title=Plancha 119 – Barrancabermeja – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QU051SnVEdmRPRmM |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Ward |first1=Dwight E. |last2=Goldsmith |first2=Richard |last3=Jimeno |first3=Andrés |last4=Cruz |first4=Jaime |last5=Restrepo |first5=Hernán |last6=Gómez |first6=Eduardo |year=2010 |title=Plancha 120 – Bucaramanga – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QdlNUbTlLbG92dk0 |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Beltrán |first1=Alejandro |last2=Lancheros |first2=José Alfredo |last3=López |first3=Carolina |last4=Chaquea |first4=Claudia |last5=Patiño |first5=Alejandro |last6=Guerra |first6=Angela |last7=Cabrera |first7=Julio C. |last8=Quintero |first8=Claudia I. |last9=Molano |first9=Simón Emilio |year=2008 |title=Plancha 134 – Puerto Parra – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QWGJzT3I3WGh6Nnc |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Angarita |first1=Leonidas |last2=Carrillo |first2=Víctor |last3=Castro |first3=Alfonso |last4=Daconte |first4=Rommel |last5=Niño |first5=Mario |last6=Pulido |first6=Orlando G. |last7=Rodríguez |first7=J. Antonio |last8=Royero |first8=José María |last9=Salinas, Carlos Ulloa and Rodrigo Vargas |first9=Rosalba |year=2009 |title=Plancha 135 – San Gil – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QWmI0U0IxSEptOWM |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Beltrán |first1=Alejandro |last2=Lancheros |first2=José Alfredo |last3=López |first3=Carolina |last4=Chaquea |first4=Claudia |last5=Patiño |first5=Alejandro |last6=Guerra |first6=Angela |last7=Cabrera |first7=Julio C. |last8=Quintero |first8=Claudia I. |last9=Molano |first9=Simón Emilio |year=2008 |title=Plancha 149 – Puerto Serviez – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QZzB1UEE3enpycms |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Beltrán |first1=Alejandro |last2=Lancheros |first2=José Alfredo |last3=López |first3=Carolina |last4=Chaquea |first4=Claudia |last5=Patiño |first5=Alejandro |last6=Guerra |first6=Angela |last7=Cabrera |first7=Julio C. |last8=Quintero |first8=Claudia I. |last9=Molano |first9=Simón Emilio |year=2008 |title=Plancha 150 – Cimitarra – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QbmV0eldmTDRvdWc |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last=Pulido González |first=Orlando |year=2009 |title=Plancha 151 – Charalá – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QVnhHc2E1d1YxSHM |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Ulloa |first1=Carlos E |last2=Rodríguez |first2=Erasmo |year=2009 |title=Plancha 170 – Vélez – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QcGU2Z19qSDBTZ28 |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Renzoni |first1=Giancarlo |last2=Rosas |first2=Humberto |year=2009 |title=Plancha 171 – Duitama – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QVU40dC0wUzhzTkk |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Fuquen M. |first1=Jaime A |last2=Osorno M |first2=José F. |year=2009 |title=Plancha 190 – Chiquinquirá – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QVEYzMnV1ekNxTDQ |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
{{citation |last1=Renzoni |first1=Giancarlo |last2=Rosas |first2=Humberto |author3-link=Fernando Etayo |last3=Etayo Serna |first3=Fernando |year=1998 |title=Plancha 191 – Tunja – 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QQzhBTXNwUWJuUDg |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}

External links

{{in lang|es}} [https://lapaleontologiaencolombia.blogspot.com/2015/12/leyvachelys-cipadi-una-nueva-especie-de.html Leyvachelys cipadi, una nueva especie de tortuga sandownidae del Cretácico inferior de Colombia]
{{in lang|es}} [https://lapaleontologiaencolombia.blogspot.com/2014/11/brachauchenius-un-superpredador-de-los.html Brachauchenius, un superpredador de los mares cretácicos]

Category:Geologic formations of Colombia

Category:Cretaceous Colombia

Category:Shale formations

Category:Shallow marine deposits

Category:Evaporite deposits

Category:Source rock formations

Category:Seal rock formations

Category:Cretaceous paleontological sites of South America

Category:Mining in Colombia

Formations

Category:First 100 IUGS Geological Heritage Sites