| 词条 | White Bluff Formation |
| 释义 |
| name = White Bluff Formation | image = | caption = | type = Formation | age = Paleogene | prilithology = marl, sand, clay | otherlithology = | namedfor = White Bluff, along the Arkansas River | namedby = | region = {{Flag|Arkansas}} | country = {{Flag|United States}} | coordinates = | unitof = Jackson Group | subunits = Pastoria Sand Member, Caney Point Marl Member, Rison Clay Member | underlies = | overlies = | thickness = | extent = | area = | map = | map_caption = }} The White Bluff Formation is a marl, sand, and clay geologic formation in Arkansas that is part of the Jackson Group. It preserves fossils dating back to the Paleogene period, specifically the Eocene. DescriptionThe White Bluff Formation is composed of three members: the Pastoria Sand Member, the Caney Point Marl Member, and the Rison Clay Member.[1]. The Pastoria Sand is a clayey sand containing glauconite and mollusca fossils. The Caney Point Marl is a chalky clay with glauconite and various invertebrate fossils. The Rison Clay is a clay with interbedded silts containing foraminifera fossils and scattered mollusca molds. [1] The entire formation was deposited as a marine sequence. [1][2] See also{{Portal|Earth sciences|Arkansas|Paleontology|Paleogene|Cenozoic}}
References1. ^1 2 {{cite journal |last1=Wilbert, Jr. |first1=Louis J. |title=The Jacksonian Stage in southeastern Arkansas |journal=Arkansas Division of Geology Bulletin |date=1953 |volume=19 |pages=37-56 |url=http://www.geology.ar.gov/pdf/Bull-19_Jacksonian_Stage_SE_AR.pdf |accessdate=29 June 2018}} 2. ^{{cite journal |last1=McFarland |first1=John D. |title=Stratigraphic summary of Arkansas |journal=Arkansas Geological Commission Information Circular |date=rev. 2004 |volume=36 |url=http://www.geology.arkansas.gov/pdf/IC-36_v.pdf |accessdate=29 June 2018}}
1 : Paleogene Arkansas |
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