Download or read book Internal Stratigraphic Correlation of the Subsurface Potomac Formation New Castle County Delaware and Adjacent Areas in Maryland and New Jersey written by Richard N. Benson and published by . This book was released on 2006 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents a new time-stratigraphic framework for the subsurface Potomac Formation of New Castle County, Delaware, part of adjacent Cecil County, Maryland, and nearby tie-in boreholes in New Jersey. The framework is based on a geophysical well-log correlation datum that approximates the contact between Upper and Lower Cretaceous sediments. This datum is constrained by age determinations based on published and unpublished results of studies of fossil pollen and spores in samples of sediment cores from boreholes in the study area. Geophysical log correlation lines established above and below the datum approximate additional chronostratigraphic surfaces. The time-stratigraphic units thus defined are not correlated parallel to the basement unconformity, as in previous practice, but instead onlap it in an updip direction. In future studies, the sedimentary facies of the Potomac Formation within each time-stratigraphic layer may be mapped and analyzed as genetically related contemporaneous units. This new stratigraphic framework will allow better delineation of the degree of lateral connection between potential aquifer sands, thus enhancing understanding of aquifer architecture.
Download or read book Chesapeake Bay Impact Structure written by Henning Dypvik and published by Geological Society of America. This book was released on 2018-10-04 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Chesapeake Bay impact structure is a well-documented example of a small group of multi-layer, marine-target impacts formed in continental shelves or beneath epeiric seas. New sedimentological and stratigraphical data and results--mainly from Chesapeake Bay brim cores (Watkins School, Langley, and Bayside)--are compared to and compiled with key crater core data"--
Download or read book Large Meteorite Impacts and Planetary Evolution IV written by W. U. Reimold and published by Geological Society of America. This book was released on 2010-01-01 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Fourth International Conference on Large Meteorite Impacts and Planetary Evolution held at the Vredefort Dome, South Africa, in Aug. 2008.
Download or read book Report of Investigations written by Delaware Geological Survey and published by . This book was released on 2006 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book First State Geology written by and published by . This book was released on 1983 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Early Flowers and Angiosperm Evolution written by Else Marie Friis and published by Cambridge University Press. This book was released on 2011-08-18 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: The recent discovery of diverse fossil flowers and floral organs in Cretaceous strata has revealed astonishing details about the structural and systematic diversity of early angiosperms. Exploring the rich fossil record that has accumulated over the last three decades, this is a unique study of the evolutionary history of flowering plants from their earliest phases in obscurity to their dominance in modern vegetation. The discussion provides comprehensive biological and geological background information, before moving on to summarise the fossil record in detail. Including previously unpublished results based on research into Early and Late Cretaceous fossil floras from Europe and North America, the authors draw on direct palaeontological evidence of the pattern of angiosperm evolution through time. Synthesising palaeobotanical data with information from living plants, this unique book explores the latest research in the field, highlighting connections with phylogenetic systematics, structure and the biology of extant angiosperms.
Download or read book Reconstructing Landscapes Across the Early to Late Cretaceous Transition Evaluating Base Level Climate and Sequence Stratigraphy from Potomac Formation Sediments in New Jersey and Delaware written by Jesse Daniel Thornburg and published by . This book was released on 2016 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mid-Cretaceous (Barremian/Aptian/Albian/Cenomanian stages) marks the transition to global greenhouse climatic conditions. The mid-Cretaceous Potomac Formation, deposited on the North American coastal plain, offers the potential to study a nonmarine fluvial/deltaic deposit that experienced changes in climate and sea level. This study involves three coreholes from New Jersey (Fort Mott and Medford) and Delaware (Summit Marina) that were used to evaluate the landscape evolution through this time interval and to develop an enhanced method of correlation between these sites. Paleosols offer excellent records of terrestrial conditions during their formation. 103 total paleosols were identified and analyzed from all three sites and grouped into five pedotypes ranging in pedogenic maturity: Gray and Gray-Red Types are weakly developed, immature soils formed under poor drainage conditions; Red and Purple Types are moderately developed soils formed under alternating wet/dry conditions; Brown Type are well-developed, mature soils formed under well drained conditions. A morphology index and two geochemical proxies (Nb and Ba/Sr) provide further information on paleoprecipitation, and drainage conditions. A conceptual model was developed linking the Nb paleoprecipitation proxy and Ba/Sr drainage proxy to determine landscape changes as a result of precipitation/evaporation versus base level. Potomac Formation Unit I displays varying dry to wet conditions up section from the unit base. The morphology index and geochemical proxies provide evidence that Unit I was sub-humid with episodes of saturation and overall drier conditions relative to overlying units. Paleoprecipitation was the main control on the formation of these paleosols. Units II (lower Albian to lower Cenomanian) and III (lower Cenomanian) have similar wet and dry conditions upsection through both units. Paleoprecipitation played a role lower in Unit II although upsection base level exerts more influence on landscape conditions. The morphology index and geochemical proxies provide evidence Units II and III were deposited under wetter conditions, experiencing sub-humid to humid conditions, with episodes of drying. Palynology also provides a correlation tool, and was analyzed here to try and establish a higher resolution of correlation. This was attempted using angiosperm diversity patterns, specifically Monocots-Magnoliids, Eudicots and the ratio of Eudicots to Monocots-Magnoliids. The inconsistent sample material as well as sparse angiosperm populations did not allow for a higher resolved correlation. A sequence stratigraphic framework was developed for the Potomac Formation. The Potomac Formation units were subdivided into packages known as Fluvial Aggradation Cycles (FACs). An analysis of FAC stacking patterns reveals potential sequence boundaries and systems tracts. FACs support the identification of unit boundaries as sequence boundaries. FACs also indicate tentative higher order sequence boundaries and provide potential additional correlative surfaces among Potomac Formation sites. This study reconstructed the landscape showing the variability in climate (precipitation/evaporation) and base-level through time that had a significant influence the formation of coastal plain paleosols. This enhances the overall understanding of how coastal plain landscapes evolve in transitions towards greenhouse climates during overall transgressions. The use of FACs has provided a potentially novel method to correlate sites at a higher resolution, creating tie points within these lithologic units. It also provided further information on the landscape evolution through this time interval, offering information on base-level and accommodation.
Download or read book Hydrogeologic Framework of the New Jersey Coastal Plain written by Otto S. Zapecza and published by . This book was released on 1989 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydrologic Data for the Potomac Formation in New Castle County Delaware written by M. M. Martin and published by . This book was released on 1982 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Report of Investigations written by Delaware Geological Survey and published by . This book was released on 1957 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stratigraphy of the Post Potomac Cretaceous Tertiary Rocks of Central Delaware written by Richard N. Benson and published by . This book was released on 1996 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stratigraphic Interpretations of the Subsurface of Delaware and the Adjacent Offshore Area written by Delaware Geological Survey and published by . This book was released on 1987 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ground water Resources of Southern New Castle County Delaware written by Bernard Cohen and published by . This book was released on 1962 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Cenozoic Rocks written by Philip B. King and published by . This book was released on 1978 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stratigraphy Correlation and Depositional Environments of the Middle to Late Pleistocene Interglacial Deposits of Southern Delaware written by Kelvin W. Ramsey and published by . This book was released on 2010 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Delaware Bay Group deposits consist of bay-margin coarse sand and gravel that fine upward to silt and silty sand. Beds of organic-rich mud were deposited in tidal marshes. Near the present Atlantic Coast, the Delaware Bay Group includes organic-rich muds and shelly muds deposited in lagoonal environments. Assawoman Bay Group deposits range from very fine, silty sands to silty clays with shells deposited in back-barrier lagoons, to fine to coarse, well-sorted sands deposited in barriers and spits. Nanticoke River Group deposits consist of coarse sand and gravel that fine upward to silty clays. Oyster shells are found associated with the clays in the Turtle Branch Formation. Organic-rich clayey silts were deposited in swamps and estuaries. Well-sorted fine sands to gravelly sands were deposited on beaches and tidal flats on the flanks of the ancestral Nanticoke River and its tributaries.
Download or read book Hydrogeologic Framework of the Coastal Plain in Maryland Delaware and the District of Columbia written by Don A. Vroblesky and published by . This book was released on 1991 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: See journals under US Geological survey. Prof. paper 1404-E.
Download or read book Summary Appraisals of the Nation s Ground water Resources Mid Atlantic Region written by Allen Sinnott and published by . This book was released on 1978 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Additional title page description: A discussion of ground water in relation to the total water resources of the region.
