This open access book presents an overview on seep systems in South China Sea. It includes numerous illustrations and photographs of the seeps that never seen before. It also introduces ...multidisciplinary research results to stimulate further research interest.
The Geologic Time Scale 2012, winner of a 2012 PROSE Award Honorable Mention for Best Multi-volume Reference in Science from the Association of American Publishers, is the framework for deciphering ...the history of our planet Earth. The authors have been at the forefront of chronostratigraphic research and initiatives to create an international geologic time scale for many years, and the charts in this book present the most up-to-date, international standard, as ratified by the International Commission on Stratigraphy and the International Union of Geological Sciences. This 2012 geologic time scale is an enhanced, improved and expanded version of the GTS2004, including chapters on planetary scales, the Cryogenian-Ediacaran periods/systems, a prehistory scale of human development, a survey of sequence stratigraphy, and an extensive compilation of stable-isotope chemostratigraphy. This book is an essential reference for all geoscientists, including researchers, students, and petroleum and mining professionals. The presentation is non-technical and illustrated with numerous colour charts, maps and photographs. The book also includes a detachable wall chart of the complete time scale for use as a handy reference in the office, laboratory or field.
The most detailed international geologic time scale available that contextualizes information in one single reference for quick desktop access. Gives insights in the construction, strengths, and limitations of the geological time scale that greatly enhances its function and its utility. Aids understanding by combining with the mathematical and statistical methods to scaled composites of global succession of events. Meets the needs of a range of users at various points in the workflow (researchers extracting linear time from rock records, students recognizing the geologic stage by their content).
Beach ridges are indicators of supratidal and intertidal depositional environments built by waves. The major factors that influence on the ridge’s formation is related to antecedent topography, ...sediment supply, sedimentary balance, and substrate gradient. They consist of siliciclastic and/or bioclastic sediments whose grain size varies from very coarse sand to very fine sand. At Santa Catarina state, progradant plains are related to Pleistocene and Holocene regressive marine processes. The Holocene marine terraces, object of this study, predominate in the coastal plains of Passo de Torres, Pinheira, Jurerê, Tijucas and Navegantes, presenting heights from 3 to 6 m in elevations and 1 to 2 m in depressions. The ridge deposits are constituted by sandy sediments, medium to very fine, composed by quartz, opaque and heavy minerals and shell fragments. The runnel deposits comprehend silt-sand-clayey sediments enriched by organic matter. The evolution of Holocene Santa Catarina beach ridges is connected to the regressive events occurred after 5,1 ky BP that indicate the position of paleo coastlines and mean sea level of the Holocene.
A homokszemcsék mikromorfológiájának vizsgálatával már közel egy évszázada foglalkoznak a kutatók, már akkor felfigyeltek néhány összefüggésre a szemcsék felszínén megfigyelhető formák, valamint a ...geológiai környezet között. Az általunk bemutatott módszer jelentősége abban rejlik, hogy ideális esetben a bélyegekből és azok együtteseiből valószínűsíteni lehet a szállítási móddal kapcsolatos különböző környezeti tényezőket és időbeli változásukat, sőt akár következtethetünk a forrásterület korábbi éghajlatára is. Folyamatosan fejlődő módszerről van szó, ezért fontos megjegyeznünk, hogy az általa tehető megállapítások még nem tekinthetők olyan biztosnak, mint a nála elterjedtebb, gyakrabban alkalmazott paleokörnyezet-határozásra használt eljárások. Munkánk célja, hogy bemutassuk ezt a törmelékes szedimentológiában alkalmazható, eddig főleg hazánkban kevéssé ismert és elterjedt vizsgálati módszert, amelynek pontosan emiatt nincsen hivatalosan bevezetett és elfogadott magyar nevezéktana. Ebből kifolyólag úttörő munkának számít hazánk tudományos életében, célunk az eredeti angol nevezéktanból kiinduló, magyar nyelvű szakkifejezések bevezetése.A módszerben sok új lehetőség rejlik (pl. statisztikai megközelítés fejlesztése, morfológiai jegyek együttes jelenlétének értelmezése), a téma pedig nemzetközi szinten is egyre népszerűbb. Korunk egyik legnagyobb környezeti kihívása a klímaváltozás. Folyamatainak minél pontosabb megismeréséhez és megértéséhez ismernünk kell ezek múltbéli megfelelőit. Erre már számos módszer létezik (pl. dendrokronológia, jégfuratok izotópösszetételének vizsgálata), ugyanakkor az üledékes szemcsék vizsgálata további értékes, új információt nyújthat a témában.
This is an open access book. This book presents new theory and methods on compiling lithofacies paleogeographic maps as a key tool for guiding geological survey on shale gas. The fundamental goal of ...the shale gas geological survey is to find the ‘dessert’ area. It is therefore suggested that the lithofacies paleogeographic study and the technique of mapping should be a solid scientific basis for shale gas exploration. It takes Ordovician Wufeng-Silurian Longmaxi Formation in Sichuan Basin and its adjacent area as an example to illustrate how to find the ‘dessert’ area of shale gas in geological survey phase by compiling lithofacies paleogeographic map. It’s a valuable reference for both scientific research and teaching courses in the fields of sedimentary lithofacies, paleogeography, stratigraphy, and oil and gas.
An estimated 8.3 billion tons of non-biodegradable plastic has been produced over the last 65 years. Much of this is not recycled and is disposed into the natural environment, has a long ...environmental residence time and accumulates in sedimentary systems worldwide, posing a threat to important ecosystems and potentially human health. We synthesize existing knowledge of seafloor microplastic distribution, and integrate this with process-based sedimentological models of particle transport, to provide new insights, and critically, to identify future research challenges. Compilation of published data shows that microplastics pervade the global seafloor, from abyssal plains to submarine canyons and deep-sea trenches (where they are most concentrated). However, few studies relate microplastic accumulation to sediment transport and deposition. Microplastics may enter directly into the sea as marine litter from shipping and fishing, or indirectly via fluvial and aeolian systems from terrestrial environments. The nature of the entry-point is critical to how terrestrially sourced microplastics are transferred to offshore sedimentary systems. We present models for physiographic shelf connection types related to the tectono-sedimentary regime of the margin. Beyond the shelf, the principal agents for microplastic transport are: (i) gravity-driven transport in sediment-laden flows; (ii) settling, or conveyance through biological processes, of material that was formerly floating on the surface or suspended in the water column; (iii) transport by thermohaline currents, either during settling or by reworking of deposited microplastics. We compare microplastic settling velocities to natural sediments to understand how appropriate existing sediment transport models are for explaining microplastic dispersal. Based on this analysis, and the relatively well-known behavior of deep-marine flow types, we explore the expected distribution of microplastic particles, both in individual sedimentary event deposits and within deep-marine depositional systems. Residence time within certain deposit types and depositional environments is anticipated to be variable, which has implications for the likelihood of ingestion and incorporation into the food chain, further transport, or deeper burial. We conclude that the integration of process-based sedimentological and stratigraphic knowledge with insights from modern sedimentary systems, and biological activity within them, will provide essential constraints on the transfer of microplastics to deep-marine environments, their distribution and ultimate fate, and the implications that these have for benthic ecosystems. The dispersal of anthropogenic across the sedimentary systems that cover Earth’s surface has important societal and economic implications. Sedimentologists have a key, but as-yet underplayed, role in addressing, and mitigating this globally significant issue.
ICESat-2's Advanced Topographic Laser Altimeter System (ATLAS) has emerged as a useful tool for calculating attenuation signals in natural surface waters, thus improving our understanding of ...particulates from open-ocean plankton to nearshore suspended terrigenous sediments. While several studies have employed methods based on Beer's Law to derive attenuation coefficients (including through a machine-learning approach), a rigorous test of specific tuning parameters and processing choices has not yet been performed. Here we present comprehensive sensitivity tests of noise removal, choice of bin sizes, surface-peak exclusion, and beam pairing across four contrasting marine environments as well as solar background removal at an additional site to quantify the impacts of these processing choices on the derived photon-based attenuation coefficient Kdph. Ultimately, calculated Kdph values were not statistically sensitive to choices of horizontal bin sizes, vertical bin sizes, and surface exclusion depths with ranges of 500–2000 m, 0.25–1.0 m, and 0.5–1.0 m, respectively. Use of strong-beam data is recommended because weak-beam data introduce additional noise, though in open-ocean waters where photon counts are sparse, it may be desirable to include weak-beam data. In a daytime/nighttime data comparison, daytime data were found to be usable, though removal of the solar background increased the Kdph estimates by ∼27–64%. A robust solution for removing afterpulses remains elusive, though a gaussian decomposition scheme was attempted. It did not, however, yield statistically different Kdph values relative to the uncorrected dataset. Detailed information about processing choices and a suggested workflow for ocean applications are provided. Together the results pave the way for expanded Kdph analyses of global datasets (including turbid coastal waters).
•Study evaluates the impact of processing choices on Kdph and offers a workflow.•Many processing terms have little impact on Kdph, including afterpulse removal.•Using strong-beam data is recommended and using daytime data is possible.
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