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Articles 871 - 900 of 2252
Full-Text Articles in Geomorphology
Evolution And Equilibration Of Artificial Morphologic Perturbations In The Form Of Nearshore Berm Nourishments Along The Florida Gulf Coast, Katherine Emily Brutsché
Evolution And Equilibration Of Artificial Morphologic Perturbations In The Form Of Nearshore Berm Nourishments Along The Florida Gulf Coast, Katherine Emily Brutsché
USF Tampa Graduate Theses and Dissertations
Inlets and channels are dredged often to maintain navigation safety. It is beneficial to reintroduce the dredged material back into the littoral system, in the form of beach or nearshore nourishments. Nourishment in the nearshore is becoming an increasingly utilized method, particularly for dredged material that contains more fine sediment than the native beach. This research examines the morphologic evolution of two different nearshore nourishments. A nearshore berm was constructed at Fort Myers Beach, Florida using mixed-sized sediment dredged from a nearby channel. The nearshore berm was placed in water depths between 1.2 and 2.4 m with the berm crest …
Volcanism-Induced Karst Landforms And Speleogenesis, In The Ankarana Plateau (Madagascar). Hypothesis And Preliminary Research, Eric Gilli
International Journal of Speleology
The Ankarana is a limestone plateau in the northern part of Madagascar, where a cave system, more than 120 km long, has been explored. The plateau is bordered by volcanoes and is cut across by several canyons. An analysis of surface landforms and caves suggests that the karst genesis was probably initiated by volcanism beneath an impervious cover. Volcanic bulging and magma intrusions may have favored a basalt-limestone assimilation process and metamorphism. The ascent of deep volcanic fluids (CO2 and SO2) from magma degassing and from limestone metamorphism, may explain the speleogenesis. Once denuded, the karst evolved …
Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst
Natural Resources Management and Environmental Sciences
Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of …
The University Of Nebraska State Museum, Robert F. Diffendal Jr.
The University Of Nebraska State Museum, Robert F. Diffendal Jr.
Robert F. Diffendal, Jr., Publications
I first walked through the doors of Morrill Hall on the main or City Campus of the University of Nebraska on a day late in August of 1962 and thought that I had entered paleontology heaven. Morrill Hall then housed the University of Nebraska State Museum (UNSM). most of the Geology Department, and some other parts of university units. I was a new graduate student hoping to pursue research in invertebrate paleontology in the Department of Geology and was on my way to see the department chairman for the first time. When I entered the building I walked through a …
Stratigraphic Framework And Landsystem Correlation For Deposits Of The Saginaw Lobe, Michigan, Usa, Ivan R. Guzman
Stratigraphic Framework And Landsystem Correlation For Deposits Of The Saginaw Lobe, Michigan, Usa, Ivan R. Guzman
Masters Theses
Since the time of the Last Glacial Maximum (LGM) the south-central portion of the Lower Michigan Peninsula has been subject to several glacial advances and retreats by the Saginaw lobe. As part of the U.S Geological Survey Great Lakes Geological Mapping Coalition projects, several rotosonic borings were drilled between 2006 and 2013 in Barry, Kalamazoo and Calhoun Counties. Gamma ray logs and textural analyses were completed for each core. Five of these borings were selected according to their diamicton (till) content and correlated using water well logs and surficial geology maps. Glacial deposits such as diamicton serve as evidence of …
Investigating Telogenetic Karst Aquifer Processes And Evolution In South-Central Kentucky, U.S., Using High-Resolution Storm Hydrology And Geochemistry Monitoring, Nicholas Lawhon
Masters Theses & Specialist Projects
Recent studies have investigated the hydrological and geochemical characteristics of karst aquifers in different settings; however, telogenetic karst aquifer processes remain poorly understood. In south-central Kentucky, the iconic Lost River Cave and Valley represents a large, complex telogenetic karst drainage basin with a series of discharge points along a collapsed section of the cave. Two Campbell Scientific® CR1000 automated dataloggers were installed at Blue Hole Four, a primary discharge point of the Lost River Karst Aquifer (LRKA). These dataloggers recorded spring discharge, water temperature, specific conductance (SpC), and pH at ten-minute intervals from January to November, 2013. During the year, …
Analysis Of Environmental Influences On Dressed Stone Decay: A Case Study Of Tafoni Development On A Hewn Djinn Block In Petra, Jordan, Kaelin M. Groom
Analysis Of Environmental Influences On Dressed Stone Decay: A Case Study Of Tafoni Development On A Hewn Djinn Block In Petra, Jordan, Kaelin M. Groom
Graduate Theses and Dissertations
Petra, Jordan captivates tourists and researchers with its dramatic sandstone cliffs, Nabatean, Roman, Byzantine and Roman architecture, and rich cultural heritage. However, increasing tourism in the valley is exacerbating stone degradation and complicating heritage management. This research analyzed environmental influences on dressed stone decay via tafoni development and evaluating cell evolution on an isolated hewn feature, known as Djinn Block X. Resembling other sandstone blocks found in the area, this irregular sandstone monument exhibits faces ranging in size from 2.5m by 3.5m to 3.9m to 4.2m (29m perimeter). Protruding features, incisions along the top, and a large platform attached to …
Geologic Constraints And Speleogenesis Of Cova Des Pas De Vallgornera, A Complex Coastal Cave From Mallorca Island (Western Mediterranean), Joaquín Ginés, Joan J. Fornós, Angel Ginés, Antoni Merino, Francesc Gràcia
Geologic Constraints And Speleogenesis Of Cova Des Pas De Vallgornera, A Complex Coastal Cave From Mallorca Island (Western Mediterranean), Joaquín Ginés, Joan J. Fornós, Angel Ginés, Antoni Merino, Francesc Gràcia
International Journal of Speleology
The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km) and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and …
Cave Deposits And Sedimentary Processes In Cova Des Pas De Vallgornera (Mallorca, Western Mediterranean), Joan J. Fornós, Joaquin Ginés, Francesc Gràcia, Antoni Merino Juncadella, Lluís Gómez-Pujol, Pere Bover
Cave Deposits And Sedimentary Processes In Cova Des Pas De Vallgornera (Mallorca, Western Mediterranean), Joan J. Fornós, Joaquin Ginés, Francesc Gràcia, Antoni Merino Juncadella, Lluís Gómez-Pujol, Pere Bover
International Journal of Speleology
The Cova des Pas de Vallgornera is an important and protected coastal cave, located in the southern part of the island of Mallorca, that outstands due to its length and the complex processes involved in its speleogenesis. Although sediments are not the main topic of interest, their presence as well as their paleontological contents are valuable evidence for paleoclimatic and chronological reconstructions of the cave morphogenesis. The sedimentary infilling is characterized by a scarce presence of clastic sedimentation, mainly composed of silts and clays, which can only be found at some minor passages in the innermost parts of the cave. …
Cosmogenic Beryllium Cycling In A Natural Forest Setting, Grace Conyers
Cosmogenic Beryllium Cycling In A Natural Forest Setting, Grace Conyers
Open Access Theses
10 Bemet , or cosmogenic beryllium, has a long half-life of 1.4 million years and quick adsorption on soil particles, which may make it ideal for dating soil erosion in historical context. However, there are questions on about the fundamental assumptions of the retentivity of 10 Bemet . This manuscript explores these assumptions and the context of nutrient cycling in a natural forest setting.
To see if 10 Bemet was being cycled through the trees, and at what rate, we looked at the[10 Bemet ] in the soil, 4 species of trees, and their leaves. The isotopic ratio 10 Be/9 …
Geology – Future Continent, Joy Wulke
Geology – Future Continent, Joy Wulke
The Transdisciplinary STEAM+ Journal
Terra Mirabila, a multi-media presentation illustrating the geological story of Stony Creek Granite back through complex sequence of geological events that spanned some 600 million years of early history.
The West Tidewater Earthflow, Northern Oregon Coast Range, Barry A. Sanford
The West Tidewater Earthflow, Northern Oregon Coast Range, Barry A. Sanford
Dissertations and Theses
The West Tidewater earthflow, one of the largest in Oregon's history, occurred in December of 1994. The earthflow is located approximately 15 km north of Jewel, Oregon near the summit ofthe Northern Oregon Coast Range Mountains. The earthflow is 900 m long and 250 m wide, giving it a surface area of 9 ha, or 22 acres. Volume is 3.5 million m3. The earthflow occurred in low strength, well-bedded, tuffaceous, carbonaceous, micaceous, clay-rich mudstone, and very fine-grained, feldspathic, clay-rich siltstone of the lower Miocene age Northrup Creek Formation. The soil clay fractions contain up to 90% smectite with …
Some Reflections On Our Experiences At Sun Yat-Sen University Since 1985, Robert F. Diffendal Jr., Anne P. Diffendal
Some Reflections On Our Experiences At Sun Yat-Sen University Since 1985, Robert F. Diffendal Jr., Anne P. Diffendal
Robert F. Diffendal, Jr., Publications
Professor Zhang Ke, Chairman of the Department of Earth Sciences at Sun Yat-sen University, has asked us to write about some of our memories from our several visits to Sun Yat-sen University, as part of the 2014 celebration of the 90th anniversary of the founding of the university and the creation of the department. We are very pleased to do so and to include with our written comments copies of some photographs that we have taken during these visits. We have gone back through our notes, books, tourist maps, photo files, and other information that we have kept as souvenirs …
Slope Stability Analysis Of Mount Meager, South-Western British Columbia, Canada, Rachel M. Hetherington
Slope Stability Analysis Of Mount Meager, South-Western British Columbia, Canada, Rachel M. Hetherington
Dissertations, Master's Theses and Master's Reports - Open
The Mount Meager Volcanic Complex (MMVC) in south-western British Columbia is a potentially active, hydrothermally altered massif comprising a series of steep, glaciated peaks. Climatic conditions and glacial retreat has led to the further weathering, exposure and de-buttressing of steep slopes composed of weak, unconsolidated material. This has resulted in an increased frequency of landslide events over the past few decades, many of which have dammed the rivers bordering the Complex. The breach of these debris dams presents a risk of flooding to the downstream communities. Preliminary mapping showed there are numerous sites around the Complex where future failure could …
Interpreting The Paleozoogeography And Sea Level History Of Thermally Anomalous Marine Terrace Faunas: A Case Study From The Last Interglacial Complex Of San Clemente Island, California, Daniel R. Muhs, Lindsey T. Groves, R. Randall Schumann
Interpreting The Paleozoogeography And Sea Level History Of Thermally Anomalous Marine Terrace Faunas: A Case Study From The Last Interglacial Complex Of San Clemente Island, California, Daniel R. Muhs, Lindsey T. Groves, R. Randall Schumann
United States Geological Survey: Publications
Marine invertebrate faunas with mixtures of extralimital southern and extralimital northern faunal elements, called thermally anomalous faunas, have been recognized for more than a century in the Quaternary marine terrace record of the Pacific Coast of North America. Although many mechanisms have been proposed to explain this phenomenon, no single explanation seems to be applicable to all localities where thermally anomalous faunas have been observed. Here, we describe one such thermally anomalous fossil fauna that was studied on the second emergent marine terrace at Eel Point on San Clemente Island. The Eel Point terrace complex is a composite feature, consisting …
Identifying Sources Of Aeolian Mineral Dust: Present And Past, Daniel R. Muhs, Joseph M. Prospero, Matthew C. Baddock, Thomas E. Gill
Identifying Sources Of Aeolian Mineral Dust: Present And Past, Daniel R. Muhs, Joseph M. Prospero, Matthew C. Baddock, Thomas E. Gill
United States Geological Survey: Publications
Aeolian mineral dust is an important component of the Earth’s environmental systems, playing roles in the planetary radiation balance, as a source of fertilizer for biota in both terrestrial and marine realms and as an archive for understanding atmospheric circulation and paleoclimate in the geologic past. Crucial to understanding all of these roles of dust is the identification of dust sources. Here we review the methods used to identify dust sources active at present and in the past. Contemporary dust sources, produced by both glaciogenic and non-glaciogenic processes, can be readily identified by the use of Earth-orbiting satellites. These data …
Coastal Geology And Recent Origins For Sand Point, Lake Superior, Timothy G. Fisher, David E. Krantz, Mario R. Castaneda, Walter L. Loope, Harry M. Jol, Ronald J. Goble, Melinda C. Higley, Samantha Dewald, Paul R. Hanson
Coastal Geology And Recent Origins For Sand Point, Lake Superior, Timothy G. Fisher, David E. Krantz, Mario R. Castaneda, Walter L. Loope, Harry M. Jol, Ronald J. Goble, Melinda C. Higley, Samantha Dewald, Paul R. Hanson
Department of Earth and Atmospheric Sciences: Faculty Publications
Sand Point is a small cuspate foreland located along the southeastern shore of Lake Superior within Pictured Rocks National Lakeshore near Munising, Michigan. Park managers’ concerns for the integrity of historic buildings at the northern periphery of the point during the rising lake levels in the mid-1980s greatly elevated the priority of research into the geomorphic history and age of Sand Point. To pursue this priority, we recovered sediment cores from four ponds on Sand Point, assessed subsurface stratigraphy onshore and offshore using geophysical techniques, and interpreted the chronology of events using radiocarbon and luminescence dating. Sand Point formed at …
Rollover, Drowning, And Discontinuous Retreat: Distinct Modes Of Barrier Response To Sea-Level Rise Arising From A Simple Morphodynamic Model, Jorge Lorenzo Trueba, Andrew Dale Ashton
Rollover, Drowning, And Discontinuous Retreat: Distinct Modes Of Barrier Response To Sea-Level Rise Arising From A Simple Morphodynamic Model, Jorge Lorenzo Trueba, Andrew Dale Ashton
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
We construct a simple morphodynamic model to investigate the long-term dynamic evolution of a coastal barrier system experiencing sea-level rise. Using a simplified barrier geometry, the model includes a dynamic shoreface profile that can be out of equilibrium and explicitly treats barrier sediment overwash as a flux. With barrier behavior primarily controlled by the maximum potential overwash flux and the rate of shoreface response, the modeled barrier system demonstrates four primary behaviors: height drowning, width drowning, constant landward retreat, and a periodic retreat. Height drowning occurs when overwash fluxes are insufficient to maintain the landward migration rate required to keep …
Nebraska Statewide Groundwater-Level Monitoring Report 2014, A. R. Young, M. E. Burbach, L. M. Howard
Nebraska Statewide Groundwater-Level Monitoring Report 2014, A. R. Young, M. E. Burbach, L. M. Howard
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Methods For Estimating Sediment Yield And Dam Capacity In The Great Lakes Watershed, Jennifer Hui
Methods For Estimating Sediment Yield And Dam Capacity In The Great Lakes Watershed, Jennifer Hui
Wayne State University Theses
Sedimentation is the most important factor in the longevity of dams built in the United States. As most dams are reaching their capacity for sediment storage, this study investigated the historical and predicted future rates of sediment accumulation as well as the remaining storage capacity. This study examined the mechanisms influencing sediment production and storage in the watershed to provide future insight regarding potential control of this process. Twelve reservoirs throughout the Great Lakes watershed were selected and analyzed for their greater applicability to the entire watershed. Both historic and new data were collected on these dams to determine how …
Convergence Of Dune Topography Among Multiple Barrier Island Morphologies, Jackie Ann Monge
Convergence Of Dune Topography Among Multiple Barrier Island Morphologies, Jackie Ann Monge
Theses and Dissertations--Geography
Wave-dominated and mixed tidal and wave energy barrier islands are assumed to have characteristic dune topographies that link to their macroscale form. However, there has been no systematic attempt to describe the linkage between barrier island macroscale form and dune topography. The goal of this thesis was to investigate how dune topographies correspond to a number of barrier island morphologies found along the southeastern U.S. Atlantic coast. Macroscale process-form variables were used to classify 77 islands into seven morphologic clusters. Islands from each cluster were selected and sites characteristic of the range of dune topographies within islands were characterized using …
Analysis Of Vesicular Porosity In Soils Using High-Resolution X-Ray Computed Tomograpy, Judith K. Turk, Robert C. Graham
Analysis Of Vesicular Porosity In Soils Using High-Resolution X-Ray Computed Tomograpy, Judith K. Turk, Robert C. Graham
Conservation and Survey Division: Faculty and Staff Publications
Vesicular horizons are common at the surface of arid and semiarid soils and play a critical role in regulating infiltration. Most methods for examining pore morphology in the vesicular horizon involve physical sectioning of the sample and individual measurement of pores, which is time-consuming and provides an incomplete view of the pores. The objectives of this study were to (i) develop methods for the classification and characterization of pores in the vesicular horizon using high resolution X-ray computed tomography (HRXCT) and (ii) use these methods to examine the distribution of pores within vesic-ular peds. Three intact peds were scanned by …
The Groundwater Atlas Of Lancaster County, Dana Divine
The Groundwater Atlas Of Lancaster County, Dana Divine
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Determining Hillslope Diffusion Rates In A Boreal Forest: Quaternary Fluvial Terraces In The Nenana River Valley, Central Alaska Range, Laurel Anne Walker
Determining Hillslope Diffusion Rates In A Boreal Forest: Quaternary Fluvial Terraces In The Nenana River Valley, Central Alaska Range, Laurel Anne Walker
Theses and Dissertations--Earth and Environmental Sciences
The subarctic boreal forest biome is predicted to experience higher magnitudes of warming than other biomes due to climate change. The effects of this warming will be pronounced in areas underlain by discontinuous permafrost where melting permafrost and distinct changes in vegetation patterns are expected. To better understand rates of hillslope diffusion in the boreal forest I have used a geomorphic process modeling approach, using data from a sequence of Quaternary fluvial terraces located in the Nenana River valley of central Alaska. I hypothesized that diffusion rates here would be slower when compared to the mid-latitudes, and faster on north …
Paleoseismic And Structural Characterization Of The Hines Creek Fault: Denali National Park And Preserve, Alaska, Sara E. Federschmidt
Paleoseismic And Structural Characterization Of The Hines Creek Fault: Denali National Park And Preserve, Alaska, Sara E. Federschmidt
Theses and Dissertations--Earth and Environmental Sciences
The Hines Creek fault (HCF) is a Holocene-active fault in central Alaska. Its trace has been mapped several times, but data on the history of fault displacement is scarce. As a major crustal-scale geologic boundary with uncertain Quaternary tectonic activity, it is a priority for more to be known about the activity of this fault to better understand the hazards it presents to the Denali National Park and Preserve and Alaskan infrastructure. This study characterizes the late Quaternary activity of the HCF through surficial geologic mapping and paleoseismic investigations. Mapping revealed a very steep (~84°-88° apparent dip), north dipping fault …
Biomechanical Effects Of Trees And Soil Thickness In The Cumberland Plateau, Michael Shouse
Biomechanical Effects Of Trees And Soil Thickness In The Cumberland Plateau, Michael Shouse
Theses and Dissertations--Geography
Previous research in the Ouachita Mountains, Arkansas suggests that, on relatively thin soils overlying bedrock, individual trees locally thicken the regolith by root penetration into bedrock. However, that work was conducted mainly in areas of strongly dipping and contorted rock, where joints and bedding planes susceptible to root penetration are more common and accessible. This project extended this concept to the Cumberland Plateau, Kentucky, with flat, level-bedded sedimentary rocks. Spatial variability of soil thickness was quantified at three nested spatial scales, and statistical relationships with other potential influences of thickness were examined. In addition, soil depth beneath trees was compared …
Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu
Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu
Department of Earth, Environment and Sustainability Faculty Publications
Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …
Tidal Pacing, Skipped Slips And The Slowdown Of Whillans Ice Stream, Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley, Douglas A. Wiens, Martin J. Pratt
Tidal Pacing, Skipped Slips And The Slowdown Of Whillans Ice Stream, Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley, Douglas A. Wiens, Martin J. Pratt
All Faculty Scholarship for the College of the Sciences
We summarize new observations of the deceleration and stick–slip motion of Whillans Ice Stream (WIS), Antarctica. We refine the location of the large sticky spots that resist motion between slip events, the locations of which are controlled by the patterns of subglacial water flow. Our examination of the long-term velocity time series for the ice stream reveals that the decadal-scale deceleration is not occurring at a steady rate, but varies at the sub-decadal timescale. This unsteady deceleration modulates the temporal evolution of a broad (~50 km across) surface-elevation bulge forming at the junction between the relatively narrow upstream portion of …
Long-Term Deformation In The Southern RíO Grande Rift As Inferred From Topographic And Uplifted Terraces, Linda K. Armour
Long-Term Deformation In The Southern RíO Grande Rift As Inferred From Topographic And Uplifted Terraces, Linda K. Armour
Open Access Theses & Dissertations
This study examines Basin and Range topography relating tectonic processes to topographic features. The observation that the terraces along either side of the Franklin Mountains were deformed and uplifted is a reflection of tectonic uplift. The uplift represents long-term deformation of the range. This led to the question of what shapes the deformation and does it represent differential subsidence into the Río Grande Rift or true uplift. A more regional study of the Sacramento, San Andres, and Guadalupe Mountains follows. Two papers form this Dissertation.
The Río Grande Rift and the Franklin Mountains, in particular, are the subject of the …
Thermobarometry And Geochronology In The Dulan Region, North Qaidam Ultrahigh-Pressure Terrane: Resolving Spatial Variation Of Ages, Temperatures, And Pressures, Megan Eileen Regel
Thermobarometry And Geochronology In The Dulan Region, North Qaidam Ultrahigh-Pressure Terrane: Resolving Spatial Variation Of Ages, Temperatures, And Pressures, Megan Eileen Regel
All Master's Theses
The Dulan ultrahigh-pressure (UHP) terrane exposes 449-422 Ma eclogites in the east and 449-418 Ma high-pressure granulites to the west, but the relationship between the units is poorly understood. Zirconium-in-rutile temperatures show an east-west 3- 5°C/km gradient in four UHP eclogites: 662-716±10°C; garnet-omphacite-phengite thermobarometry of peak conditions yields 659-730±82°C, 25.3-27.1±3.2 kbars. Zircon U-Pb ages of four eclogites are the same within uncertainty, averaging 434±2.9 Ma. Tiin- zircon thermometry and rare earth element patterns indicate these ages represent eclogite facies metamorphism. One high-pressure/high-temperature (HP/HT) granulite yields a minimum rutile temperature of 773±4°C. Previous thermobarometry of highpressure granulites yields ≥800°C and 14-17 …