Slope Floor Research Articles

Evaluating habitat, prey, and mesopredator associations in a community of marine birds

Abstract Offshore wind energy development on the US Atlantic Continental Shelf has brought attention to the need for marine spatial planning efforts to reduce potential conflict between wind turbines and marine animals, including seabirds. We evaluated the effects of marine mammals, fishes, and habitat characteristics on the distribution and relative abundance of marine birds off the coast of Delaware, Maryland, and Virginia. From May 2012 to 2014, we collected line transect data from 14 shipboard surveys, and novel high-resolution digital videography data from 14 aerial surveys. We compiled five habitat covariates: three static (distance to shore, sea floor slope, and sediment grain size), and two dynamic (sea surface temperature, salinity). We additionally analysed two seabird community covariates: the density of observed marine mammals and detected fish. Using zero-altered models, we tested our hypothesis that plunge-diving seabird species would show positive associations with marine mammals. Our results provide statistical evidence that, alongside competition, facilitative interactions occur among pelagic communities, where subsurface predators improve the detectability and accessibility of prey to surface-feeding seabirds. This study highlights the importance of quantifying community and ecological influences on avian abundance, particularly in predicting the potential exposure of marine birds and mammals to offshore development.

EVALUASI KESESUAIAN ERGONOMI ANTARA FASILITAS KAMAR MANDI DENGAN FISIOLOGI DAN ANTROPOMETRI LANSIA

Bathroom was major personal hygiene facilities for elderly in Hargo Dedali Nursing HomeSurabaya. Elderly bathroom design need to consider with ergonomic factor for elderly to minimize of falling. The purpose of this study was describing suitability of bathroom facilities ergonomic according physiological and elderly anthropometric factors in the Nursing Home. This study was conducted with cross-sectional design with descriptive analysis approach. Observations and measurements were taken at the place and variables were personal hygiene facilities, physiological, and elderly anthropometric. Data that used were primary data based on observations and interviews and secondary data drawn from the place. The result showed that elderly bathroom ergonomic design were height of closet 42,5 ±2,609 cm; height of bathing tub 68,65±6,492 cm; height of water cock 90,09±6,067 cm; volume of water dipper1000 ml; height of hand rail 80,09±6,067 cm; diameter of handful 4,6±0,2 cm at persentile5th; slope of floor ≥ 40 with rough floor texture; lenght of doorleaf with handle 16 cm; lighting during the day and the night for more than 100 lux. The conclusion was that not all bathroom facilities at nursing home eligible for elderly. Advice that can be given were the bathroom need adjustment size with ergonomic values obtained and necessary uniformity in design was not only space but also uniformity in size according to the physiological and elderly anthropometric who can access to bathroom independently. Keywords: ergonomics, bathroom, elderly

An Assessment of Regional Variations in Martian Modified Impact Crater Morphology

AbstractImpact craters on Mars have been extensively modified by ancient geologic processes that may have included rainfall and surface runoff, snow and ice, denudation by lava flows, burial by eolian material, or others. Many of these processes can leave distinct signatures on the morphometry of the modified impact crater as well as the surrounding landscape. To look for signs of potential regional differences in crater modification processes, we conducted an analysis of different morphometric parameters related to modified impact craters located in the Margaritifer Sinus, Sinus Sabaeus, Iapygia, Mare Tyrrhenum, Aeolis, and Eridania quadrangles, including depth, crater wall slope, crater floor slope, the curvature between the interior wall and the crater floor slope, and the curvature between the interior wall and surrounding landscape. A Welch's t test analysis comparing these parameters shows that fresh impact craters (Type 4) have consistent morphologies regardless of their geographic location examined in this study, which is not unexpected. Modified impact craters both in the initial (Type 3) and terminal stages (Type 1) of modification also have statistically consistent morphologies. This would suggest that the processes that operated in the late Noachian were globally ubiquitous, and that modified craters eventually reached a stable crater morphology. However, craters preserved in advanced (but not terminal) stages of modification (Type 2) have morphologies that vary across the quadrangles. It is possible that these variations reflect spatial differences in the types and intensity of geologic processes that operated during the Noachian, implying that the ancient climate also varied across regions.

Impact of Channel Slope on Cutthroat Flume Performance

Abstract. Cutthroat flumes are widely used in field projects to estimate discharge via a stage-discharge relationship. Flumes are commonly tested and calibrated in a laboratory to develop the stage-discharge relationship, but field installations often occur under non-idealized conditions, specifically with respect to bed slope. We calibrated a cutthroat flume with dimensions of 0.91 m length and 0.35 m throat width for bed slopes ranging from 0% to 2% to represent a range of field conditions. The experiment was conducted in the Water Resources Lab of the College of Engineering at the University of Wyoming, which provided highly accurate discharge measurements. Results showed negligible impact of slope on the resulting stage-discharge relationship under free flow conditions. We were able to generate a composite rating curve for bed slopes ranging from 0% to 2% for flumes of this size. Our study indicates that, under free flow conditions, longitudinal floor slopes ranging from 0% to 2% do not significantly affect the cutthroat flume rating curve. Keywords: Cutthroat flume, Flume calibration, Free flow, Rating curve, Stream discharge.

Submarine slope–fan sedimentation in an ancient forearc related to contemporaneous magmatism: The Upper Cretaceous Izumi Group, southwestern Japan

AbstractThe Izumi Group in southwestern Japan is considered to represent deposits in a forearc basin along an active volcanic arc during the late Late Cretaceous. The group consists mainly of felsic volcanic and plutonic detritus, and overlies a Lower to Upper Cretaceous plutono‐metamorphic complex (the Ryoke complex). In order to reconstruct the depositional environments and constrain the age of deposition, sedimentary facies and U–Pb dating of zircon grains in tuff were studied for a drilled core obtained from the basal part of the Izumi Group. On the basis of the lithofacies associations, the core was subdivided into six units from base to top, as follows: mudstone‐dominated unit nonconformably deposited on the Ryoke granodiorite; tuffaceous mudstone‐dominated unit; tuff unit; tuffaceous sandstone–mudstone unit; sandstone–mudstone unit; and sandstone‐dominated unit. This succession suggests that the depositional system changed from non‐volcanic muddy slope or basin floor, to volcaniclastic sandy submarine fan. Based on a review of published radiometric age data of the surrounding region of the Ryoke complex and the Sanyo Belt which was an active volcanic front during deposition of the Izumi Group, the U–Pb age (82.7 ±0.5 Ma) of zircon grains in the tuff unit corresponds to those of felsic volcanic and pyroclastic rocks in the Sanyo Belt.

Forest Site Classification in the Southern Andean Region of Ecuador: A Case Study of Pine Plantations to Collect a Base of Soil Attributes

Forest site classification adapted to the respective site conditions is one prerequisite for sustainable silviculture. This work aims to initiate the forest site classification for pine plantations in the southern Andean region of Ecuador. Forest productivity, estimated by the dominant height of 20-year-old trees (DH20), was related to data from climate, topography, and soil using 23 plots installed in pine plantations in the province of Loja. Forest site productivity was classified as: low (class C: 13.4 m), middle (class B: 16.6 m), and high (Class A: 22.3 m). Strong determinants to differentiate the forest site classes were: the short to medium term available Ca and K stocks (organic layer + mineral soil standardized to a depth of 60 cm), soil acidity, the C:N ratio, clay and sand content, forest floor thickness, altitude, and slope. The lowest forest productivity (Class C) is mainly associated with the lowest short to medium term available K and Ca stocks. Whereas, in site classes with the highest forest productivity, pines could benefit from a more active microbial community releasing N and P, since the soil pH was about 1 unit less acidic. This is supported by the lowest forest floor thickness and the narrowest C:N ratio.

One-Trip Multizone Sand-Control-Completion System in the Gulf of Mexico Lower Tertiary

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 27183, “Current State of the One-Trip Multizone Sand-Control-Completion System and the Conundrum Faced in the Gulf of Mexico Lower Tertiary,” by Bruce Techentien, Tommy Grigsby, and Thomas Frosell, Halliburton, prepared for the 2016 Offshore Technology Conference, Houston, 2–5 May. The paper has not been peer reviewed. Copyright 2016 Offshore Technology Conference. Reproduced by permission. This paper provides perspective on the current state of multizone completion technology and issues encountered in the industry with developing a system that offers increased capabilities to meet the increasing challenges presented by the Lower Tertiary in the Gulf of Mexico (GOM). The multizone technology has proved to be an enabler for cost-efficient completions in the shallow-well environment and in the high-cost ultradeepwater environment requiring high-rate fracture-stimulation treatments. Lower Tertiary GOM The Lower Tertiary play is south and west of the Miocene area in the GOM and is, consequently, in deeper water. The Lower Tertiary is located approximately 175 miles offshore and is estimated at 80 miles wide and up to 300 miles long. Water depths are from 5,000 to 10,000 ft. Production targets are at depths of 10,000 to 30,000 ft subsea. The Tertiary trend is from 66 million to 38 million years old. Within the Lower Tertiary, the Lower Wilcox portion presents sheet to amalgamated-sheet sands considered to be part of a regional basin floor fan system. The Late Paleocene to Early Eocene (Wilcox equivalent) reservoirs are considered to be laterally extensive sheet sands that were deposited in deep water. These reservoirs are distributed across an area largely covered by the allochthonous Sigsbee salt canopy. It is this canopy that causes additional problems beyond merely the water depth and the well depth required to reach the reservoirs. These exploration plays depend on understanding the updip fluvial/deltaic stratigraphic architecture and the potential for partitioning of reservoir-quality sandstones across the depositional shelf into the slope and basin floor environments. The Lower Tertiary is estimated to contain up to 15 billion bbl of oil. Current State of Multizone Technology The Generation IV multizone system has been deployed successfully in the Lower Tertiary by multiple operators. To the authors’ knowledge, the multistage completion system and enhanced single-trip multizone fracturing systems had been installed in 10 wells as of the summer of 2015, with additional well installations planned. These systems are rated to 10,000 psi, and the enhanced single-trip multizone tool system offering an open-hole variant was installed in one five-zone completion.

Pulse propagation in turbidity currents

AbstractSubmarine turbidity currents are a key mechanism in the transportation of clastic sediments to deep seas. Such currents may initiate with a complex longitudinal flow structure comprising flow pulses (for example, by being sourced from retrogressive sea floor slope failures) or acquire such structure during run‐out (for example, following flow combination downstream of confluences). A key question is how far along channel pathway complex flow structure is preserved within turbidity currents as they run out and thus if flow initiation mechanism and proximity to source may be inferred from the vertical structure of their deposits. To address this question, physical modelling of saline flows has been conducted to investigate the dynamics of single‐pulsed versus multi‐pulsed density driven currents. The data suggest that, under most circumstances, individual pulses within a multi‐pulsed flow must merge. Therefore, initiation signatures will only be preserved in deposits upstream of the merging point and may be distorted approaching it; downstream of the merging point, all initiation signals will be lost. This new understanding of merging phenomenon within multi‐pulsed gravity currents broadens our ability to interpret multi‐pulsed turbidites.

Sedimentary record of subsidence pulse at the Triassic/Jurassic boundary interval in the Slovenian Basin (eastern Southern Alps)

AbstractIn the Alpine Realm the Early Jurassic is characterized by the disintegration and partial drowning of vast platform areas. In the eastern part of the Southern Alps (present-day NW Slovenia), the Julian Carbonate Platform and the adjacent, E-W extending Slovenian Basin underwent partial disintegration, drowning and deepening from the Pliensbachian on, whereas only nominal environmental changes developed on the large Dinaric (Friuli, Adriatic) Carbonate Platform to the south (structurally part of the Dinarides). These events, however, were preceded by an earlier - and as yet undocumented extensional event - that took place near the Triassic/Jurassic boundary. This paper provides evidence of an accelerated subsidence from four selected areas within the Slovenian Basin, which show a trend of eastwardly-decreasing deformation. In the westernmost (Mrzli vrh) section - the Upper Triassic platform-margin - massive dolomite is overlain by the earliest Jurassic toe-of-slope carbonate resediments and further, by basin-plain micritic limestone. Further east (Perbla and Liščak sections) the Triassic-Jurassic transition interval is marked by an increase in resedimented carbonates. We relate this to the increasing inclination and segmentation of the slope and adjacent basin floor. The easternmost (Mt. Porezen) area shows a rather monotonous, latest Triassic-Early Jurassic basinal sedimentation. However, changes in the thickness of the Hettangian-Pliensbachian Krikov Formation point to a tilting of tectonic blocks within the basin area. Lateral facies changes at the base of the formation indicate that the tilting occurred at and/or shortly after the Triassic/Jurassic boundary

Reconstruction of Large Orbital Posterior Floor Wall Fracture Considering Orbital Floor Slope Using Endoscope.

Reconstruction of a large orbital fracture extending to the posterior wall of the maxillary sinus is difficult and challenging. In this study, the authors present transconjunctival or transcaruncular approach using endoscopy and layered porous polyethylene barrier sheets to manage large orbital floor wall fracture. A retrospective review of all patients who underwent reconstruction of large orbital floor wall fractures between June 2009 and July 2015 was conducted. Patient demographics, degree of enophthalmos, ocular motility and diplopia test results, and surgical complications were reviewed. This study included 53 eyes of 53 patients. The mean time from trauma to surgery was 34.1 days (range, 1-360 days). The average postoperative follow-up period was 6.1 months (range, 3-14 months). The degrees of enophthalmos preoperatively, and 1 week, 1 month, and 3 months postoperatively were -1.98 mm (range, -1.5 to -3 mm), 0.13 mm (range, -1.0 to +1.5 mm), -0.09 mm (range, -2.0 to +1.5 mm), and -0.43 mm (range, -2.0 to +1.0 mm), respectively. The mean improvement in enophthalmos at 3 months postoperation was 1.55 mm (P < 0.001). There was only 1 patient with residual 2 mm enophthalmos at 3 months postoperation. There were no definite surgical complications in any patient. Sufficient dissection to the posterior extent of the fracture and reconstruction of the orbital floor slope are the most important surgical factors to prevent residual enophthalmos. The authors believe using an endoscope and layered porous polyethylene are effective techniques in challenging patients with large orbital wall fracture.

Frequency and risk-factors analysis of Escherichia coli O157:H7 in Bali-cattle

Cattle are known as the main reservoir of zoonotic agents verocytotoxin-producing Escherichia coli. These bacteria are usually isolated from calves with diarrhea and/or mucus and blood. Tolerance of these agents to the environmental conditions will strengthen of their transmission among livestock. A total of 238 cattle fecal samples from four sub-districts in Badung, Bali were used in this study. Epidemiological data observed include cattle age, sex, cattle rearing system, the source of drinking water, weather, altitude, and type of cage floor, the cleanliness of cage floor, the slope of cage floor, and the level of cattle cleanliness. The study was initiated by culturing of samples onto eosin methylene blue agar, then Gram stained, and tested for indole, methyl-red, voges proskauer, and citrate, Potential E.coli isolates were then cultured onto sorbitol MacConkey agar, and further tested using O157 latex agglutination test and H7 antisera. Molecular identification was performed by analysis of the 16S rRNA gene, and epidemiological data was analyzed using STATA 12.0 software. The results showed, the prevalence of E. coli O157:H7 in cattle at Badung regency was 6.30% (15/238) covering four sub districts i.e. Petang, Abiansemal, Mengwi, and Kuta which their prevalence was 8.62%(5/58), 10%(6/60), 3.33%(2/60), and 3.33(2/60)%, respectively. The analysis of 16S rRNA gene confirmed of isolates as an E. coli O157:H7 strain with 99% similarities. Furthermore, the risk factors analysis showed that the slope of the cage floor has a highly significant effect (P<0.05) to the distribution of infection. Consequently, implementing this factor must be concerned in order to decrease of infection.

WORLD OCEAN - LAST RESERVE OF HUMANITY

Analysis of mineral resources base located in offshore zone and ocean space is an important aspect of development of industrial and economic potential. The issues of control over the Earth’s mineral resources as one of the most important components of geopolitical leadership are considered. It is shown that mineral resources of shelf zone, continental slope, and ocean floor are of the greatest interest from the viewpoint of possible commercial development. Data on the major oil and natural gas fields, deep-sea deposits of polymetallic sulfides, ferromanganese nodules, and cobalt-manganese crusts are analyzed. The mechanisms of state management in the field of using the resources of World Ocean and developing marine mining industry in Russia are substantiated.

Laboratory Investigation of the Effect of the Size of Orifice on the Performance of Curvature Submerge Vanes for Sediment Leaching of the Vortex Settling Basin's Floor

In this paper, considering the accumulation of the sediments on the floor of the vortex settling basin during sediment extracting, curvature submerge vanes were used on the floor of the vortex basin and the effect of the size of the orifice was studied on the performance of the curvature submerge vanes for sediment leaching of the floor of the basin. Experiments were performed on a physical model with a height of 90 cm and a diameter of 206 cm and a floor slope of 10% and also three orifices were used with diameters of 59, 46 and 36 mm. The submerge vanes were placed in different arrangements and different radial sections. The results of the experiments indicated that the performance of the vanes in sediment extracting on the floor is primarily influenced by the orifice and secondly by the arrangements and radial sections of the vanes’ placements.

Secondary Reconstruction of Residual Enophthalmos Using an Endoscope and Considering the Orbital Floor and Medial Wall Slope.

To present a transconjunctival and transcaruncular endoscopy approach involving layered porous polyethylene barrier implants to manage residual posttraumatic enophthalmos and to evaluate the effectiveness of this technique. The authors performed a retrospective review of all patients who underwent secondary reconstruction of orbital wall fractures because of residual enophthalmos between June 2008 and July 2015. Patients' demographics, degree of enophthalmos, ocular motility, diplopia test results, and surgical complications were reviewed. This study included 16 eyes (4 right eyes and 12 left eyes) of 16 patients (14 males and 2 females). The mean time interval from trauma to surgery was 7.1 months (range, 1-18 months). The average postoperative follow-up period was 6.4 months (range, 3-18 months). The degree of enophthalmos preoperatively and at 1 week, 1 month, and 3 months postoperatively was -2.47 mm (range, -2 to -3 mm), 0.5 mm (range, -0.5 to +2.5 mm), -0.06 mm (range, -0.5 to +1.5 mm), and -0.44 mm (range, -1.5 to +1.0 mm), respectively. There were no definite surgical complications in any patients. Dissection to the posterior margin of the fracture and reconstruction of the orbital floor slope are the most important surgical factors to prevent residual enophthalmos and scarring with recurrent diplopia. Demonstration of slight exophthalmos of the corrected side of about 1 to 2 mm at the end of the operation is also necessary. The authors believe that surgery using an endoscope and layered porous polyethylene is very useful for secondary reconstruction.

Coupling Between Shelf-Edge Architecture and Submarine-Fan Growth Style In A Supply-Dominated Margin

The linkage between relative sea-level change, shelf-edge architecture, and evolution of Maastrichtian basin-floor fans in the Washakie Basin, Wyoming, has been investigated at the scale of lobes, lobe complexes, and submarine fans using 630 wireline logs. The basin-floor fan deposits of two adjacent clinothems form lobate shapes on the toe of slope and basin floor. The earlier lobe complexes of the two clinothems are only weakly developed (from no deposition to up to 3.9 km3 respectively in Clinothems 9 and 10), indicating small volumes of sandy sediment delivered to deep water. The lobe complexes (up to 6.4 km3 of each lobe complex) of Clinothem 9 aggraded with fixed slope channels and without strong basinward or lateral migration (40–170 m aggradation, 4–8 km progradation with 4 km lateral shift) and did so in concert with a highly aggradational shelf edge (50 m/100 ky with 5.5 km progradation) during a period of interpreted relative sea-level rise. In contrast, the deep-water lobe complexes (up to 11.5 km3 of each lobe complex) of Clinothem 10 prograded continuously for 15–18 km on the basin floor (with 60–210 m aggradation) coeval with a flattish shelf-edge progradation (25 km/100 ky with 25 m aggradation) and an interpreted minimal sea-level rise or stillstand. The depocenters of lobe complexes in Clinothem 10 switched laterally (7–14 km) by compensational stacking and slope-channel avulsions. During the late development of both clinothems, the deep-water lobe complexes became smaller (up to 1.9 and 6.1 km3 respectively in Clinothems 9 and 10) or retreated concurrently with shelf flooding. Washakie Basin deep-water fans thus evolved through stages of initiation, aggradation or progradation, and retreat of lobe complexes. The submarine-fan growth stages of these deep-water depocenters were surprisingly well linked to coeval changes in shelf-edge trajectory between successive, ca. 100 ky maximum flooding events on the shelf. We suggest that the close linkage of lobe-complex stacking pattern with shelf-edge behavior was because the Washakie Basin formed under greenhouse conditions with a continuously high, Laramide sediment discharge to the deep-water fans while the feeder deltas were at the shelf edge, despite significant sediment reworking of shelf-edge deltas by waves and tides.

Endoscopic Reconstruction of Isolated Orbital Floor Wall Fracture Considering Orbital Floor Slope

To present a surgical technique for the reconstruction of the orbital floor slope in patients of isolated orbital floor fracture and to evaluate the effectiveness of this technique. The authors conducted a retrospective review of all patients who underwent reconstruction of isolated orbital floor wall fracture between June 2010 and July 2015. The authors reviewed patient demographics, degree of enophthalmos, ocular motility and diplopia test results, and surgical complications. This study included 33 eyes from 33 patients. The mean time interval from trauma to surgery was 24.9 days (range, 5-360 days). The average postoperative follow-up period was 7.4 months (range, 3-28 months). The degree of enophthalmos preoperatively and 1 week, 1 month, and 3 months postoperatively was -1.55 mm (range, -3 to -0.5 mm), 0.22 mm (range, -0.5 to +1.0 mm), -0.06 mm (range, -1.0 to +1.0 mm), and -0.13 mm (range, -0.5 to +0.5 mm), respectively. The mean improvement in enophthalmos at postoperative 3 months was 1.41 mm compared with that in the preoperative data (P value <0.001). There were no patients with residual enophthalmos greater than 1 mm after reconstruction. Endoscopic orbital floor slope reconstruction in isolated orbital floor wall fracture using a layered porous polyethylene barrier implant is a very useful surgical technique for safely identifying the posterior margin of a fracture and easily reconstructing the orbital floor slope. The demonstration of slight exophthalmos of the corrected side about 1 to 2 mm at the end of the operation was also necessary.

Fine-scale foraging cues for African penguins in a highly variable marine environment

Table S1. Top five candidate generalized linear mixed-effects models (GLMMs) predicting the occurrence probability of African penguins in relation to bathymetry (Bat), bathymetry as a quadratic term (Bat), chlorophyll a (Chla), distance to the nearest colony (Dcol), distance to the nearest neighbouring colony (DNcol), sea floor slope (Sl), sea surface temperature (SST), and sea surface temperature as a quadratic term (SST). AICc scores were used to rank models and those within 4 ΔAICc were model averaged to derive fixed effect estimates used in generating plots (see Fig. 4 in the main article).

Hydromorphological parameters of natural channel behavior in conditions of the Hercynian System and the flysch belt of the Western Carpathians on the territory of the Czech Republic

A fundamental prerequisite for assessing the current ecological status of streams is the establishment of reference conditions for each stream type that serve as a benchmark. The hydromorphological reference conditions reflect the natural channel behavior, which is extremely variable. Significant parameters of natural channel behavior were determined using a combination of four selected statistical methods: Principal Component Analysis, Agglomerative Hierarchical Clustering, correlation, and regression. Macroscale analyses of data about altitude, stream order, channel slope, valley floor slope, sinuosity, and characteristics of the hydrological regime were conducted for 3197 reaches of major rivers in the Czech Republic with total length of 15,636km. On the basis of selected significant parameters and their threshold values, channels were classified into groups of river characteristics based on shared behaviors. The channel behavior within these groups was validated using hydromorphological characteristics of natural channels determined during field research at reference sites. Classification of channels into groups confirmed the fundamental differences between channel behavior under conditions of the Hercynian System and the flysch belt of the Western Carpathians in the Czech Republic and determined a specific group in the flattened high areas of mountains in the Bohemian Massif. Validating confirmed the distinctions between groups of river characteristics and the uniqueness of each one; it also emphasized the benefits of using qualitative data and riparian zone characteristics for describing channel behavior. Channel slope, entrenchment ratio, bed structure, and d50 were determined as quantitative characteristics of natural channel behavior.

Effects of micro-topographies on stand structure and tree species diversity in an old-growth evergreen broad-leaved forest, southwestern Japan

Stand structure and species diversity were studied in correspondence with micro-topographies in an old-growth forest in southwestern Japan. The study was conducted in a 200×200m2 permanent plot, which were divided into 400 subplots using grids of 10m×10m. Subplots were categorized to four micro-topographies as crest slope (CS), head hollow (HH), upper slope (US) and lower slope (LS), basing on slope of forest floor and plot position, and to two elevational zones as below 450 m and above 450 m. Tree censuses for all individuals with diameter at breast height (DBH) ⩾ 5 cm were conducted in 2009 and 2013. The results indicated that CS had subplot means of living stems, dead stems, DBH, basal area (G), and basal area increment (▵G) significantly higher than that in LS. While, means of recruited stems and Shannon diversity index were significantly lower. Comparing between below and above 450 m elevational zones indicated the significantly higher parameters of stand structure and species diversity in above 450 m elevational zone. The differences of edaphic conditions led to difference of density of living stems, species density, DBH, G, and ▵G among micro-topographies. Therefore, crest slope, upper slope, and higher elevational zones should be encouraged for the purposes of carbon accumulation and storage. While, the lower elevational zones should be used for the purposes of species diversity conservation.

Role of sea-level change in deep water deposition along a carbonate shelf margin, Early and Middle Permian, Delaware Basin: implications for reservoir characterization

Abstract The architecture and sedimentary characteristics of deep water deposition can reflect influences of sea-level change on depositional processes on the shelf edge, slope, and basin floor. Outcrops of the northern slope and basin floor of the Delaware Basin in west Texas are progressively exposed due to canyon incision and road cutting. The outcrops in the Delaware Basin were measured to characterize gravity flow deposits in deep water of the basin. Subsurface data from the East Ford and Red Tank fields in the central and northeastern Delaware Basin were used to study reservoir architectures and properties. Depositional models of deep water gravity flows at different stages of sea-level change were constructed on the basis of outcrop and subsurface data. In the falling-stage system tracts, sandy debris with collapses of reef carbonates are deposited on the slope, and high-density turbidites on the slope toe and basin floor. In the low-stand system tracts, deep water fans that consist of mixed sand/mud facies on the basin floor are comprised of high- to low-density turbidites. In the transgression and high-stand system tracts, channel-levee systems and elongate lobes of mud-rich calciturbidite deposits formed as a result of sea level rise and scarcity of sandy sediment supply. For the reservoir architecture, the fan-like debris and high-density turbidites show high net-to-gross ratio of 62 %, which indicates the sandiest reservoirs for hydrocarbon accumulation. Lobe-like deep water fans with net-to-gross ratio of 57 % facilitate the formation of high quality sandy reservoirs. The channel-levee systems with muddy calciturbidites have low net-to-gross ratio of 30 %.