Feltville Formation
Encyclopedia
The Feltville Formation is a mapped bedrock unit primarily in New Jersey
, with one known outlier in Pennsylvania
. It is named for the Deserted Village of Feltville in Watchung Reservation
, New Jersey, which is near where its type section was described by paleontologist Paul E. Olsen
.
.
, which is mostly playa
and alluvial fan
deposits resulting from the rifting of Pangea. The primarily red color of this formation is often evidence that the sediments were deposited in arid conditions. However, the Feltville Formation differs from the Passaic Formation in that it contains a more significant portion of non-red layers, which were laid down by deep lakes present during wetter periods.
, can be found in limestone layers within the formation. In other layers, indeterminate fossil ornithischian tracks have been noted , along with additional reptile and dinosaur prints. Fossil plant remains, as well as root structures and pollen, are also found in the formation.
.
in New Jersey.
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
, with one known outlier in Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
. It is named for the Deserted Village of Feltville in Watchung Reservation
Watchung Reservation
Watchung Reservation is the largest park in Union County, New Jersey, United States. It is bounded by the city of Summit, the borough of Mountainside, the townships of Berkeley Heights, Scotch Plains, and Springfield. The reservation consists mainly of the upper valley of Blue Brook, between the...
, New Jersey, which is near where its type section was described by paleontologist Paul E. Olsen
Paul E. Olsen
Paul E. Olsen is an American paleontologist and author and co-author of a large number of technical papers. Growing up as a teenager in Livingston, New Jersey, he was instrumental in Riker Hill Fossil Site being named a National Natural Landmark as a teenager by sending President Richard Nixon a...
.
Description
The Feltville Formation is composed of red, gray, and white sandstone of varying grain thickness, as well as red, gray, and black siltstone and calcareous mudstone. Sandstone/siltstone layers tend to be alternatingly massive and cross-bedded. Black to white carbonaceous limestone layers exist near the base of the formation. Additionally, pebbles and cobbles of quartz are embedded within layers of sandstone and siltstone that interfinger with the Feltville Formation near Oakland, New JerseyOakland, New Jersey
Oakland is a borough in Bergen County, New Jersey, United States. As of the 2010 United States Census, the borough population was 12,754.Oakland was incorporated as a borough by an Act of the New Jersey Legislature on April 8, 1902, from portions of Franklin Township.-History:The Van Allen House...
.
Depositional Environment
The Feltville Formation can be characterized as a continuation of the Passaic FormationPassaic Formation
The Passaic Formation is a mapped bedrock unit in Pennsylvania, New Jersey, and New York. It was previously known as the Brunswick Formation since it was first described in the vicinity of New Brunswick, New Jersey. It is now named for the city of Passaic, New Jersey, which is near where its type...
, which is mostly playa
Dry lake
Dry lakes are ephemeral lakebeds, or a remnant of an endorheic lake. Such flats consist of fine-grained sediments infused with alkali salts. Dry lakes are also referred to as alkali flats, sabkhas, playas or mud flats...
and alluvial fan
Alluvial fan
An alluvial fan is a fan-shaped deposit formed where a fast flowing stream flattens, slows, and spreads typically at the exit of a canyon onto a flatter plain. A convergence of neighboring alluvial fans into a single apron of deposits against a slope is called a bajada, or compound alluvial...
deposits resulting from the rifting of Pangea. The primarily red color of this formation is often evidence that the sediments were deposited in arid conditions. However, the Feltville Formation differs from the Passaic Formation in that it contains a more significant portion of non-red layers, which were laid down by deep lakes present during wetter periods.
Fossils
Fish fossils, commonly those of the ray-finned SemiontusSemionotus
Semionotus is an extinct genus of ray-finned fish found throughout Northern Pangaea during the late Triassic, becoming extinct at the start of the Jurassic.-External links:...
, can be found in limestone layers within the formation. In other layers, indeterminate fossil ornithischian tracks have been noted , along with additional reptile and dinosaur prints. Fossil plant remains, as well as root structures and pollen, are also found in the formation.
Age
The Feltville Formation rests conformably above the Orange Mountain Basalt and below the Preakness Basalt, placing its deposition somewhere between approximately 199 and 196 million years ago during the early Jurassic stage known as the HettangianHettangian
The Hettangian is the earliest age or lowest stage of the Jurassic period of the geologic timescale. It spans the time between 199.6 ± 0.6 Ma and 196.5 ± 1 Ma . The Hettangian follows the Rhaetian and is followed by the Sinemurian.In Europe stratigraphy the Hettangian is a part of the time span in...
.
Economic Uses
The Feltville Formation was once mined for freestone, as indicated by a historical work detailing quarrying operations at the base of Preakness MountainPreakness Range
The Preakness Range is a range of the trap rock Watchung Mountains on the western edge of the Newark Basin in northern New Jersey. A large portion of this range is included in High Mountain Park Preserve, offering miles of hiking trails with vistas overlooking New Jersey and New York City...
in New Jersey.
See also
- Geology of New JerseyGeology of New JerseyThe Geology of New Jersey consists of four distinct physiographic provinces. They are: the Atlantic Coastal Plain Province, the Piedmont Province, the Highlands Province, and the Ridge and Valley Province.-Coastal Plain:...
- Geology of PennsylvaniaGeology of PennsylvaniaThe Geology of Pennsylvania consists of six distinct physiographic provinces, three of which are subdivided into different sections. Each province has its own economic advantages and geologic hazards and play an important role in shaping everyday life in the state...
- List of dinosaur-bearing rock formations
- List of stratigraphic units with ornithischian tracks
- Indeterminate ornithischian tracks
- List of stratigraphic units with ornithischian tracks