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30-468: The formation is mostly marine and can be divided into three intergrading facies . The first, located primarily to the south, is mostly limestone with some interbedded shale and sandstone . The second facies, located to the north and northwest, is mostly gray shale with some thick limestone and thin sandstone beds. The third facies, found to the northeast, is mostly shale, limestone (including sandy and oolitic limestone ) and arkosic sandstone. Thickness

60-438: A facies series . Palynofacies Palynology is the study of microorganisms and microscopic fragments of mega-organisms that are composed of acid-resistant organic material and occur in sediments , sedimentary rocks , and even some metasedimentary rocks. Palynomorphs are the microscopic, acid-resistant organic remains and debris produced by a wide variety of plants , animals , and Protista that have existed since

90-601: A branch of paleontology and paleobotany , involves fossil palynomorphs from the Precambrian to the Holocene for their usefulness in the relative dating and correlation of sedimentary strata . Palynology is also used to date and understand the evolution of many kinds of plants and animals. In paleoclimatology , fossil palynomorphs are studied for their usefulness in understanding ancient Earth history in terms of reconstructing paleoenvironments and paleoclimates. Palynology

120-528: A considerable number of spores and herb pollen grains. There is a study of pollen samples taken from sediments of Swedish lakes by Trybom (1888); pine and spruce pollen was found in such profusion that he considered them to be serviceable as " index fossils ". Georg F. L. Sarauw studied fossil pollen of middle Pleistocene age ( Cromerian ) from the harbour of Copenhagen . Lagerheim (in Witte 1905) and C. A.Weber (in H. A. Weber 1918) appear to be among

150-478: A depositional environment "migrates" laterally, sediments of one depositional environment come to lie on top of another. In Russia the law is known as Golovkinsky-Walther's law, honoring also Nikolai A. Golovkinsky . A classic example of this law is the vertical stratigraphic succession that typifies marine transgressions and regressions . Ideally, a sedimentary facies is a distinctive rock unit that forms under certain conditions of sedimentation , reflecting

180-435: A group of "facies descriptors" which must be distinct, reproducible and exhaustive. A reliable facies description of an outcrop in the field would include: composition, texture, sedimentary structure(s), bedding geometry, nature of bedding contact, fossil content and colour. The sequence of minerals that develop during progressive metamorphism (that is, metamorphism at progressively higher temperatures and/or pressures) define

210-443: A number of unique sites within a given area, or samples from a single site with a record through time, such as samples obtained from peat or lake sediments. More recent studies have used the modern analog technique in which paleo-samples are compared to modern samples for which the parent vegetation is known. When the slides are observed under a microscope, the researcher counts the number of grains of each pollen taxon. This record

240-529: A particular process or environment. Sedimentary facies are either descriptive or interpretative. Sedimentary facies are bodies of sediment that are recognizably distinct from adjacent sediments that resulted from different depositional environments. Generally, geologists distinguish facies by the aspect of the rock or sediment being studied. Facies based on petrological characters (such as grain size and mineralogy ) are called lithofacies , whereas facies based on fossil content are called biofacies . A facies

270-600: Is 700–1,615 feet (213–492 meters). The formation rests conformably on the Sandia Formation and is disconformably overlain by the Alamitos Formation . The formation contains fusulinids of Desmoinesian ( Moscovian ) age. The formation was first named by Baltz and Myers in 1984, who considered it correlative with the lower part of the Madera Formation . However, in 2004, Kues and Giles recommended restricting

300-414: Is quite useful in disciplines such as archeology , in honey production, and criminal and civil law . In archaeology, palynology is widely used to reconstruct ancient paleoenvironments and environmental shifts that significantly influenced past human societies and reconstruct the diet of prehistoric and historic humans. Melissopalynology , the study of pollen and other palynomorphs in honey , identifies

330-725: Is required for sexual reproduction in flowering plants. By the late 1870s, as optical microscopes improved and the principles of stratigraphy were worked out, Robert Kidston and P. Reinsch were able to examine the presence of fossil spores in the Devonian and Carboniferous coal seams and make comparisons between the living spores and the ancient fossil spores. Early investigators include Christian Gottfried Ehrenberg ( radiolarians , diatoms and dinoflagellate cysts ), Gideon Mantell ( desmids ) and Henry Hopley White (dinoflagellate cysts). Quantitative analysis of pollen began with Lennart von Post 's published work. Although he published in

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360-449: Is the complete assemblage of organic matter and palynomorphs in a fossil deposit. The term was introduced by the French geologist André Combaz  [ wikidata ] in 1964. Palynofacies studies are often linked to investigations of the organic geochemistry of sedimentary rocks . The study of the palynofacies of a sedimentary depositional environment can be used to learn about

390-638: Is usually further subdivided. The characteristics of the rock unit come from the depositional environment and from the original composition. Sedimentary facies reflect their depositional environment, each facies being a distinct kind of sediment for that area or environment. Since its inception in 1838, the facies concept has been extended to related geological concepts. For example, characteristic associations of organic microfossils, and particulate organic material, in rocks or sediments, are called palynofacies . Discrete seismic units are similarly referred to as seismic facies. Sedimentary facies are described in

420-667: The Greek words paluno meaning 'to sprinkle' and pale meaning 'dust' (and thus similar to the Latin word pollen ). The archive-based background to the adoption of the term palynology and to alternative names (e.g. paepalology , pollenology ) has been exhaustively explored. It has been argued there that the word gained general acceptance once used by the influential Swedish palynologist Gunnar Erdtman . Pollen analysis in North America stemmed from Phyllis Draper , an MS student under Sears at

450-563: The Madera Group to shelf and marginal basin beds of Desmoinean (upper Moscovian) to early Virgilian age, which excluded the Porvenir Formation. Spencer G. Lucas and coinvestigators also exclude the Porvenir Formation from the Madera Group. Facies (geology) In geology , a facies ( / ˈ f eɪ ʃ ɪ . iː z / FAY -shih-eez , US also / ˈ f eɪ ʃ iː z / FAY -sheez ; same pronunciation and spelling in

480-838: The Swedish language, his methodology gained a wide audience through his lectures. In particular, his Kristiania lecture of 1916 was important in gaining a wider audience. Because the early investigations were published in the Nordic languages ( Scandinavian languages ), the field of pollen analysis was confined to those countries. The isolation ended with the German publication of Gunnar Erdtman 's 1921 thesis. The methodology of pollen analysis became widespread throughout Europe and North America and revolutionized Quaternary vegetation and climate change research. Earlier pollen researchers include Früh (1885), who enumerated many common tree pollen types, and

510-535: The University of Oklahoma. During her time as a student, she developed the first pollen diagram from a sample that depicted the percentage of several species at different depths at Curtis Bog. This was the introduction of pollen analysis in North America; pollen diagrams today still often remain in the same format with depth on the y-axis and abundances of species on the x-axis. Pollen analysis advanced rapidly in this period due to advances in optics and computers. Much of

540-454: The chemical preparation of materials for palynological study. Acetolysis was developed by Gunnar Erdtman and his brother to remove these fine cellulose materials by dissolving them. In acetolysis the specimen is treated with acetic anhydride and sulfuric acid , dissolving cellulistic materials and thus providing better visibility for palynomorphs. Some steps of the chemical treatments require special care for safety reasons, in particular

570-461: The depositional palaeoenvironments of sedimentary rocks in exploration geology, often in conjunction with palynological analysis and vitrinite reflectance. Palynofacies can be used in two ways: The earliest reported observations of pollen under a microscope are likely to have been in the 1640s by the English botanist Nehemiah Grew , who described pollen and the stamen, and concluded that pollen

600-520: The first to undertake 'percentage frequency' calculations. The term palynology was introduced by Hyde and Williams in 1944, following correspondence with the Swedish geologist Ernst Antevs , in the pages of the Pollen Analysis Circular (one of the first journals devoted to pollen analysis, produced by Paul Sears in North America). Hyde and Williams chose palynology on the basis of

630-460: The late Proterozoic . It is the science that studies contemporary and fossil palynomorphs (paleopalynology), including pollen , spores , orbicules , dinocysts , acritarchs , chitinozoans and scolecodonts , together with particulate organic matter (POM) and kerogen found in sedimentary rocks and sediments . Palynology does not include diatoms , foraminiferans or other organisms with siliceous or calcareous tests . The name of

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660-1105: The non-organic fraction. Palynomorphs may be composed of organic material such as chitin , pseudochitin and sporopollenin . Palynomorphs form a geological record of importance in determining the type of prehistoric life that existed at the time the sedimentary strata was laid down. As a result, these microfossils give important clues to the prevailing climatic conditions of the time. Their paleontological utility derives from an abundance numbering in millions of palynomorphs per gram in organic marine deposits, even when such deposits are generally not fossiliferous . Palynomorphs, however, generally have been destroyed in metamorphic or recrystallized rocks. Typical palynomorphs include dinoflagellate cysts , acritarchs , spores , pollen , plant tissue, fungi , scolecodonts (scleroprotein teeth, jaws, and associated features of polychaete annelid worms), arthropod organs (such as insect mouthparts), and chitinozoans . Palynomorph microscopic structures that are abundant in most sediments are resistant to routine pollen extraction. A palynofacies

690-450: The plural) is a body of rock with distinctive characteristics. The characteristics can be any observable attribute of rocks (such as their overall appearance, composition, or condition of formation) and the changes that may occur in those attributes over a geographic area. A facies encompasses all the characteristics of a rock including its chemical, physical, and biological features that distinguish it from adjacent rock. The term "facies"

720-473: The science and organisms is derived from the Greek Ancient Greek : παλύνω , romanized :  palynō , "strew, sprinkle" and -logy ) or of "particles that are strewn". Palynology is an interdisciplinary science that stands at the intersection of earth science ( geology or geological science) and biological science ( biology ), particularly plant science ( botany ). Biostratigraphy ,

750-436: The science was revised by Johannes Iversen and Knut Fægri in their textbook on the subject. Chemical digestion follows a number of steps. Initially the only chemical treatment used by researchers was treatment with potassium hydroxide (KOH) to remove humic substances; defloculation was accomplished through surface treatment or ultra-sonic treatment, although sonification may cause the pollen exine to rupture. In 1924,

780-474: The sources of pollen in terms of geographical location(s) and genera of plants. This not only provides important information on the ecology of honey bees, it also an important tool in discovering and policing the criminal adultriation and mislabeling of honey and its products. Forensic palynology uses palynomorphs as evidence in criminal and civil law to prove or disprove a physical link between objects, people, and places. Palynomorphs are broadly defined as

810-417: The study of organic remains, including microfossils , and microscopic fragments of mega-organisms that are composed of acid-resistant organic material and range in size between 5 and 500 micrometres . They are extracted from soils, sedimentary rocks and sediment cores , and other materials by a combination of physical (ultrasonic treatment and wet sieving ) and chemical (acid digestion) procedures to remove

840-413: The use of hydrofluoric acid (HF) to digest silicate minerals was introduced by Assarson and Granlund, greatly reducing the amount of time required to scan slides for palynomorphs. Palynological studies using peats presented a particular challenge because of the presence of well-preserved organic material, including fine rootlets, moss leaflets and organic litter. This was the last major challenge in

870-469: The use of HF which diffuses very fast through the skin and, causes severe chemical burns, and can be fatal. Another treatment includes kerosene flotation for chitinous materials. Once samples have been prepared chemically, they are mounted on microscope slides using silicon oil, glycerol or glycerol-jelly and examined using light microscopy or mounted on a stub for scanning electron microscopy . Researchers will often study either modern samples from

900-470: Was introduced by the Swiss geologist Amanz Gressly in 1838 and was part of his significant contribution to the foundations of modern stratigraphy , which replaced the earlier notions of Neptunism . Walther's law of facies, or simply Walther's law, named after the geologist Johannes Walther , states that the vertical succession of facies reflects lateral changes in environment. Conversely, it states that when

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