Puget Group | |
---|---|
Stratigraphic range: Paleogene | |
Type | Group |
Sub-units | Tiger Mountain, Tukwila, Renton |
Lithology | |
Primary | Deltaic |
Other | Marine, Riverine, Volcanic |
Location | |
Region | King County, Washington |
Country | United States |
The Puget Group is a geologic group in Washington (state). It preserves fossils dating back to the Paleogene period.
In the northern area of group around Renton, Washington, the Group has been divided into three formations (from oldest to youngest), the Tiger Mountain Formation, the Tukwila Formation, and Renton Formation. [1] [2] Robin Burnham (1994) specifies that these formations have not been defined and extended to Puget Group outcrops to the south within the Green River gorge and all of the Tukwila formation rocks are missing. The Puget Group has been mapped across a total of six western Washington geographic quadrangles. [1]
The total deposition time has been estimated to be as short as approximately 7.7 million years, from around 45 to 36 million years ago based on isotopic data reported in 1993 or as long as 51 to 34 million years ago based on the paleofloristic data of Wolfe (1968, 1977) [1]
The Western North American floras of the Eocene were divided into four floral "stages" by Jack Wolfe (1968) based on work with the Puget Group plant fossils. The four stages, Franklinian, Fultonian, Ravenian, and Kummerian covered the Early Eocene through early Oligocene, and three of the four were given informal early/late substages. Wolfe tentatively deemed the Franklinian as Early Eocene, the Fultonian as Middle Eocene, the Ravenian as Late, and the Kummerian as Early Oligocene. [3] The beginning of the Kummerian was refined by Gregory Retallack et al (2004) as 40 mya, with a refined end at the Eocene-Oligocene boundary where the younger Angoonian floral stage starts. [4]
The Chuckanut Formation in northwestern Washington, its extension in southwestern British Columbia, and various related formations in central Washington are fluvial sedimentary formations of Eocene age, deposited from about 54 million years ago to around 34 million years ago. The nature of the deposits and included plant fossils indicate a low-lying coastal plain with a subtropical climate; the nature of the sediments indicates metamorphic sources in northeastern Washington.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1977.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1968.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1926.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1936.
Florissantia is an extinct genus of flowering plants in the Malvaceae subfamily Sterculioideae known from western North America and far eastern Asia. Flower, fruit, and pollen compression fossils have been found in formations ranging between the Early Eocene through to the Early Oligocene periods. The type species is Florissantia speirii and three additional species are known, Florissantia ashwillii, Florissantia quilchenensis, and Florissantia sikhote-alinensis.
Sassafras hesperia is an extinct species of flowering plant in the family Lauraceae.
The Klondike Mountain Formation is an Early Eocene (Ypresian) geological formation located in the northeast central area of Washington state. The formation is comprised of volcanic rocks in the upper unit and volcanic plus lacustrine (lakebed) sedimentation in the lower unit. the formation is named for the type location designated in 1962, Klondike Mountain northeast of Republic, Washington. The formation is a lagerstätte with exceptionally well-preserved plant and insect fossils has been found, along with fossil epithermal hot springs.
The Belgrade Formation is a limestone geologic formation in North Carolina characterized by limestone coquina mixed with sand, and thinly laminated clays. It preserves fossils dating back to the Paleogene period.
The White River Formation is a geologic formation of the Paleogene Period, in the northern Great Plains and central Rocky Mountains, within the United States.
The Yegua Formation is a geologic formation in Texas. It preserves fossils dating back to the Paleogene period.
The Virgin Formation is a geologic formation in Utah. It preserves fossils dating back to the Triassic period.
The Renton Formation is a geologic formation in Washington (state) within the Puget Group. It preserves fossils dating back to the Paleogene period.
The Santa Susana Formation is a Paleogene period geologic formation in the Simi Hills and western Santa Susana Mountains of southern California.
The Tukwila Formation is a geological formation in King County, Washington within the Puget Group. It is named after Tukwila area, which is close to the formation. The formation consists of various fossils of marine origin.
Pinus latahensis is an extinct species of conifer in the pine family Pinaceae. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States, and southern British Columbia, Canada.
Pseudolarix wehrii is an extinct species of golden larch in the pine family (Pinaceae). The species is known from early Eocene fossils of northern Washington state, United States, and southern British Columbia, Canada, along with late Eocene mummified fossils found in the Qikiqtaaluk Region, Nunavut, Canada.
Dipteronia brownii is an extinct species in the soapberry family (Sapindaceae) described in 2001. Fossils of D. brownii are known from stratigraphic formations in North America and Asia ranging in age between Paleocene to Early Oligocene.
Alnus parvifolia is an extinct species of flowering plant in the family Betulaceae related to the modern birches. The species is known from fossil leaves and possible fruits found in early Eocene sites of northern Washington state, United States, and central British Columbia, Canada.