Download or read book Palynology of the Monmouth Group Maastrichtian from Monmouth Co New Jersey U S A written by Gerald Lee Waanders and published by . This book was released on 1974 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution of the Cretaceous Ocean climate System written by Enriqueta Barrera and published by Geological Society of America. This book was released on 1999-01-01 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Palynology and Age of South Hospah Coal bearing Deposits McKinley County New Mexico written by Abolfazl Jameossanaie and published by . This book was released on 1987 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bulletin written by Abolfazl Jameossanaie and published by . This book was released on 1987 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1973 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies in Eastern Energy and the Environment written by American Association of Petroleum Geologists. Eastern Section. Meeting and published by . This book was released on 1994 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Palaeontographica written by and published by . This book was released on 1980 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petroleum Abstracts written by and published by . This book was released on 1975 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography and Index to Palaeobotany and Palynology written by Hans Tralau and published by . This book was released on 1983 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geology and Paleontology of Five Cores from Screven and Burke Counties Eastern Georgia written by Lucy E. Edwards and published by . This book was released on 2001 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Dissertation Index written by and published by . This book was released on 1973 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Palynology written by and published by . This book was released on 1977 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bulletin written by and published by . This book was released on 1987 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Geological Survey Professional Paper written by and published by . This book was released on 1984 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography and Index of Geology written by and published by . This book was released on 1976 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cephalopods from the Cretaceous Tertiary Boundary Interval on the Atlantic Coastal Plain with a Description of the Highest Ammonite Zones in North America written by Neil H. Landman and published by . This book was released on 2007 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geological investigations in the upper Manasquan River Basin, central Monmouth County, New Jersey, reveal a Cretaceous/Tertiary (= Cretaceous/Paleogene) succession consisting of approximately 2 m of the Tinton Formation overlain by 2 m of the Hornerstown Formation. The top of the Tinton Formation consists of a very fossiliferous unit, approximately 20 cm thick, which we refer to as the Pinna Layer. It is laterally extensive and consists mostly of glauconitic minerals and some angular quartz grains. The Pinna Layer is truncated at the top and is overlain by the Hornerstown Formation, which consists of nearly equal amounts of glauconitic minerals and siderite. The base of the Hornerstown Formation is marked by a concentration of siderite nodules containing reworked fossils. This layer also contains a few fossils of organisms that were living in the environment during the time of reworking. At some downdip sites, there is an additional layer (the Burrowed Unit), which is sandwiched between the top of the Pinna Layer and the concentrated bed of nodules. This unit is very thin and is characterized by large burrows piping down material from above. The Pinna Layer is abundantly fossiliferous and represents a diverse, nearshore marine community. It contains approximately 110 species of bivalves, gastropods, cephalopods, echinoids, sponges, annelids, bryozoans, crustaceans, and dinoflagellates. The cephalopods include Eutrephoceras dekayi (Morton, 1834), Pachydiscus (Neodesmoceras) mokotibensis Collignon, 1952, Sphenodiscus lobatus (Tuomey, 1856), Eubaculites carinatus (Morton, 1834), Eubaculites latecarinatus (Brunnschweiler, 1966), Discoscaphites iris (Conrad, 1858), Discoscaphites sphaeroidalis Kennedy and Cobban, 2000, Discoscaphites minardi Landman et al., 2004b, Discoscaphites gulosus (Morton, 1834), and Discoscaphites jerseyensis, n.sp. The dinoflagellates include Palynodinium grallator Gocht, 1970, Thalassiphora pelagica (Eisenack, 1954) Eisenack & Gocht, 1960, Deflandrea galeata (Lejeune-Carpentier, 1942) Lentin & Williams, 1973, and Disphaerogena carposphaeropsis Wetzel, 1933. These ammonites and dinoflagellates are indicative of the uppermost Maastrichtian, corresponding to the upper part of calcareous nannofossil Subzone CC26b. The mode of occurrence of the fossils in the Pinna Layer suggests an autochthonous accumulation with little or no postmortem transport. Many of the benthic organisms are preserved in life position. For example, specimens of Pinna laqueata Conrad, 1858, are oriented in a vertical position, similar to that of modern members of this genus. The echinoids also occur in aggregations of hundreds of individuals, suggesting gregarious feeding behavior. In addition, there are monospecific clusters of baculites and scaphites. These clusters are biological in origin and could not have been produced by hydraulic means. Scaphite jaws are also present, representing the first reports of these structures in the Upper Cretaceous of the Atlantic Coastal Plain. They occur both as isolated specimens and inside the body chamber, and indicate little or no postmortem transport. The Pinna Layer represents a geologically short interval of time. The fact that most of the animals are mature suggests that the community persisted for at least 5-10 years. If multiple generations of animals are present, perhaps reflecting multiple episodes of colonization and burial, then this unit probably represents more time, amounting to several tens of years. The fact that the Pinna Layer is truncated at the top implies a still longer period of time, amounting to hundreds of years. These age estimates are consistent with observed rates of sedimentation in nearshore environments. Iridium analyses of 37 samples of sediment from three sites in the Manasquan River Basin reveal an elevated concentration of iridium of 520 pg/g, on average, at the base of the Pinna Layer. The iridium profile is aymmetric with an abrupt drop off above the base of this unit and a gradual decline below the base. The elevated concentration of iridium is not as high as that recorded from some other Cretaceous/Tertiary boundary sections. However, it is sufficiently above background level to suggest that it is related to the global Ir anomaly documented at many other localities, and attributed to a bolide impact. The position of the iridium anomaly at the base of the Pinna Layer is inconsistent with the biostratigraphic data, because this anomaly occurs below the unit containing fossils indicative of the uppermost Maastrichtian. We present two alternative hypotheses: (1) If the enriched concentration of iridium is in place, it marks the Cretaceous/Tertiary boundary by reference to the global stratotype section and point at El Kef, Tunisia. The position of the iridium anomaly further implies that the Pinna community was living at the moment of impact and may even have flourished in its immediate wake. Subsequently, the community may have been buried by pulses of mud-rich sediment, possibly associated with enhanced riverine discharge following the impact. The Burrowed Unit may represent a subsequent pulse of riverine discharge that scoured the top of the Pinna Layer. (2) The iridium anomaly was originally located at the top of the Pinna Layer and was displaced downward due to bioturbation and/or chemical diffusion. This hypothesis implies that the Pinna Layer was deposited prior to the deposition of the iridium. The Pinna community may have died before or at the moment of impact. Erosion of the top of the Pinna Layer and deposition of the Burrowed Unit may have been associated with events immediately following the impact. In both hypotheses, the sea floor experienced an extended period of erosion and reworking in the early Danian, which may have lasted for several hundred thousand years, producing a concentrated lag of siderite nodules containing reworked fossils in the basal part of the Hornerstown Formation. This lag deposit is equivalent to the Main Fossiliferous Layer at the base of the Hornerstown Formation elsewhere in New Jersey. This period of erosion and reworking was probably associated with a transgression in the early Danian. The post-impact community was greatly reduced in diversity, with most of the species representing Cretaceous survivors.
Download or read book Deltaic and Shelf Deposits in the Cretaceous Blackhawk Formation and Mancos Shale Grand County Utah written by Marjorie A. Chan and published by Utah Geological Survey. This book was released on 1991 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
