Edge Slopes Research Articles

Planar Drawings with Few Slopes of Halin Graphs and Nested Pseudotrees

The planar slope numberpsn(G)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{\\,\ extrm{psn}\\,}}(G)$$\\end{document} of a planar graph G is the minimum number of edge slopes in a planar straight-line drawing of G. It is known that psn(G)∈O(cΔ)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{\\,\ extrm{psn}\\,}}(G) \\in O(c^{\\Delta })$$\\end{document} for every planar graph G of maximum degree Δ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Delta $$\\end{document}. This upper bound has been improved to O(Δ5)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$O(\\Delta ^5)$$\\end{document} if G has treewidth three, and to O(Δ)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$O(\\Delta )$$\\end{document} if G has treewidth two. In this paper we prove psn(G)≤max{4,Δ}\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{\\,\ extrm{psn}\\,}}(G) \\le \\max \\{4,\\Delta \\}$$\\end{document} when G is a Halin graph, and thus has treewidth three. Furthermore, we present the first polynomial upper bound on the planar slope number for a family of graphs having treewidth four. Namely we show that O(Δ2)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$O(\\Delta ^2)$$\\end{document} slopes suffice for nested pseudotrees.

Characterization and assessment of projection probability density function and enhanced sampling in self-collimation SPECT.

We have recently reported a self-collimation SPECT (SC-SPECT) design concept that constructs sensitive detectors in a multi-ring interspaced mosaic architecture to simultaneously improve system spatial resolution and sensitivity. In this work, through numerical and Monte-Carlo simulation studies, we investigate this new design concept by analyzing its projection probability density functions (PPDF) and the effects of enhanced sampling, i.e. having rotational and translational object movements during imaging. We first quantitatively characterize PPDFs by their widths and edge slopes. Then we compare the PPDFs of an SC-SPECT and a series of multiple-pinhole SPECT (MPH-SPECT) systems and assess the impact of PPDFs - combined with enhanced sampling - on image contrast recovery coefficient and variance through phantom studies. We show the PPDFs of SC-SPECT have steeper edges and a wider range of width, and these attributes enable SC-SPECT to achieve better performance.

Remnant wetlands under palm swamps in the Araripe Plateau, Brazilian semiarid

Palm swamps are typical of the plateaus in the Brazilian savanna, but they are present in remnant in the Brazilian semiarid region, exceptionally in selective concave sectors of the edge and steep slopes at the Araripe Plateau. This study aimed to investigate the genesis and evolution of remnant wet soils under buriti palms/palm swamps in the Brazilian semiarid. Three pedons were selected, described, and classified according to the World Reference Base for soil resources. Soil samples were collected from the surface down to the lithic contact at each pedon. Morphology, chemical, and physical attributes were analyzed. Optically stimulated luminescence (OSL) dating was applied to buried horizons at soil profile soil profile number 1. Our results show that remnant wetlands are associated with dynamics of the hydrogeological conditions and the regional relief, strongly influenced by the morphostructure and the current morphogenesis of the Araripe Plateau. In clear contrast with typical semiarid soils, the hydrolysis and ferrolysis have produced acid, hyperdystrophic, and C-rich horizons. Evidence of colluvium and alluvium show that the soils are polycyclic. The ages between <200 to 850 yr reveal evidence of a parent material of colluvium/alluvial origin from a current sedimentation phase, attributed to erosion scarp, mass movements, and fluvial flow with low capacity.

Optical Properties and Moisture Stability of HfO2 Thin Films Prepared by Ion Assisted Deposition for UV Applications

In this study the progress in the realization of environmentally stable, high phase thickness, long-pass edge filters for UV applications is reported. These filters are characterized by extremely sharp transitions from full transmittance to deep blocking. Such filters are manufactured via physical vapor deposition of Hafnia (HfO2). Filters with highest phase thickness exhibit the steepest edge slopes. In this work we produce two types of filters, the first one manufactured using Ion Assisted Deposition (IAD), and the second one prepared by Physical Vapor Deposition (PVD) technique. When comparing the results for moisture stability of edge filters produced by IAD and PVD, it is found that the filters produced with ion assist exhibit wet-dry shifts in edge wavelength location less than 0.05%.

Fully automated image quality evaluation on patient CT: Multi-vendor and multi-reconstruction study.

While the recent advancements of computed tomography (CT) technology have contributed in reducing radiation dose and image noise, an objective evaluation of image quality in patient scans has not yet been established. In this study, we present a patient-specific CT image quality evaluation method that includes fully automated measurements of noise level, structure sharpness, and alteration of structure. This study used the CT images of 120 patients from four different CT scanners reconstructed with three types of algorithm: filtered back projection (FBP), vendor-specific iterative reconstruction (IR), and a vendor-agnostic deep learning model (DLM, ClariCT.AI, ClariPi Inc.). The structure coherence feature (SCF) was used to divide an image into the homogeneous (RH) and structure edge (RS) regions, which in turn were used to localize the regions of interests (ROIs) for subsequent analysis of image quality indices. The noise level was calculated by averaging the standard deviations from five randomly selected ROIs on RH, and the mean SCFs on RS was used to estimate the structure sharpness. The structure alteration was defined by the standard deviation ratio between RS and RH on the subtraction image between FBP and IR or DLM, in which lower structure alterations indicate successful noise reduction without degradation of structure details. The estimated structure sharpness showed a high correlation of 0.793 with manually measured edge slopes. Compared to FBP, IR and DLM showed 34.38% and 51.30% noise reduction, 2.87% and 0.59% lower structure sharpness, and 2.20% and -12.03% structure alteration, respectively, on an average. DLM showed statistically superior performance to IR in all three image quality metrics. This study is expected to contribute to enhance the CT protocol optimization process by allowing a high throughput and quantitative image quality evaluation during the introduction or adjustment of lower-dose CT protocol into routine practice.

The Performance on Slope Number of Hypercube, Normal Representation of Butterfly and Benes Networks

Many quality measures have been defined for graph drawings. In order to optimize these measures, slope number is considered to minimize the distinct edge slopes. The edges of the graphs are designed here as straight line segments. A number of distinct slopes required to draw the graph is called slope number. In this paper the slopenumber is discussed for known parallel architectures like hypercube, butterfly and benes networks. In addition to that the characterization of these networks is investigated and the results are observed for the defined problem.

An automatic stopping criterion for nonlinear anisotropic diffusion

Nonlinear anisotropic diffusion (NAD) filtering is a procedure based on nonlinear evolution PDEs which seeks to improve images qualitatively by removing noise while preserving details and even enhancing edges. However, well-known implementations are sensitive to parameters which are necessarily tuned to sharpen a narrow range of edge slopes; otherwise, edges are either blurred or staircased [Kee2002]. One important parameter is the iterations number, for that reason, in this paper a stopping criterion to halt the diffusion process is proposed. To meet this goal, two stopping criteria were compared. The first is the stopping criterion proposed by Joao et. al. [Joa2016], which is based on the Mean Squared Error (MSE). The second is our proposed method based on the CIRR contrast measure. To this end, a comparative analysis of five diffusion methods is performed. Four of them are nonlinear anisotropic diffusion methods and the fifth is the Perona-Malik method. According to the tests performed, the number of iterations required by the smoothing algorithms using the proposed stopping criterion is lower.

Biodiversity and distribution of meiofauna in the Gioia, Petrace and Dohrn Canyons (Tyrrhenian Sea)

Habitat heterogeneity is a major structuring agent of benthic assemblages promoting high turnover in species composition and ultimately contributing to overall higher diversity. Submarine canyons, a pervasive feature of the continental margins worldwide, increase habitat heterogeneity at multiple spatial scales. In the present study, we test the hypothesis that different topographic structures or/and food sources controlling the abundance, biomass and biodiversity (using meiofauna and nematodes as a model study) in canyon systems. To do so, we compared different topographic structures: canyon edge, thalweg and axis, and the upper shelf and open slope in the Gulf of Gioia (Gioia and Petrace Canyons) and in the Gulf of Naples (Dohrn Canyon) (Tyrrhenian Sea) at different depths. Our results suggest that meiofaunal abundance and biomass are generally higher in the canyon thalwegs than in the canyon edge or adjacent open slopes at regional scale. This pattern is not always confirmed for biodiversity and when thalwegs are compared to different topographic structures within the Gioia Canyon system. In our study, the role of food quantity and quality is preeminent to explain the spatial distribution of meiofaunal variables among different topographic structures at 200-m while habitat heterogeneity become relevant at 500-m and within the Dohrn Canyon. In Gioia and Petrace Canyons we observed a high food availability is associated to specific topographic structures (thalwegs) that influenced the meiofaunal abundance and diversity distribution and nematode diversity and species composition. Each topographic structure shows a high number of exclusive species that contributes to a high species turnover and high overall biodiversity in all canyon systems. Changes in nematode composition determine also differences in the functional diversity (trophic guilds composition) and life strategy of the nematode assemblages. Our findings reveal that the presence of different topographic structures influences the spatial distribution of food quality and quantity that determine the presence of exclusive taxa and species enhancing both local and regional diversity.

Depositional environments beneath the shelf-edge slopes of the Great Barrier Reef, inferred from foraminiferal assemblages: IODP Expedition 325

To understand sea-level changes since the Last Glacial Maximum (LGM) and their effects on coral reef systems, the shelf-edge slopes of the Great Barrier Reef (GBR) were cored during the Integrated Ocean Drilling Program (IODP) Expedition 325. Recovered unconsolidated sediments beneath the submerged shelf edge reefs contain abundant foraminiferal tests, which record changes in depositional environments and paleo-water depths. A total of 177 sediment samples were collected from 17 holes along three transects located within two geographical areas (Noggins Pass and Hydrographers Passage), and were analyzed to determine stratigraphic changes in foraminiferal assemblages (2–0.5 mm size fraction). Results show that four foraminiferal assemblages (A, B, C and D) are delineated by multivariate analyses (Q-mode cluster analysis and non-metric multidimensional scaling: NMDS), and these assemblages correspond to a back-reef to reef margin zone (0–10 m deep; Assemblage A), an upper photic zone (10–30 m deep) associated with hard substrates (Assemblage B), an intermediate to lower photic zone (30–90 m deep) characterized by soft substrates (Assemblage C), and a lower photic zone (90–130 m deep) only found in modern shelf slopes (Assemblage D). Gradual shifts in these four foraminiferal assemblages superimposed on a two-dimensional NMDS ordination mainly reflect water-depth gradients and the relative dominance of two substrate types (hard and soft substrates). Pre-LGM (older than Marine Isotope Stage 3: ≥MIS3) sediments along transects at Hydrographers Passage were deposited at intermediate to lower photic zones. In contrast, relatively shallow-water sequences found in ≥MIS3 deposits at Noggins Pass likely owe their origin to either turbidite and/or land slide processes. The lack of Assemblage D in ≥MIS3 deposits from all transects could be related to lowering temperature and/or increasing terrestrial influences (i.e. more light attenuation). Shallowing upward sequences found in LGM (MIS 2) deposits at Hydrographers Passage are likely related to stepwise sea-level falls to the full extent of the LGM. These foraminifer-based paleoenvironmental interpretations suggest that the GBR shelf edge slopes have changed their depositional environments continuously in response to sea-level fluctuations during the last glacial cycle.

Polygons with prescribed edge slopes: configuration space and extremal points of perimeter

We describe the configuration space $$\mathbf {S}$$ of polygons with prescribed edge slopes, and study the perimeter $${\mathcal {P}}$$ as a Morse function on $$\mathbf {S}$$ . We characterize critical points of $${\mathcal {P}}$$ (these are tangential polygons) and compute their Morse indices. This setup is motivated by a number of results about critical points and Morse indices of the oriented area function defined on the configuration space of polygons with prescribed edge lengths (flexible polygons). As a by-product, we present an independent computation of the Morse index of the area function (obtained earlier by Panina and Zhukova).

Crystal quality improvement of sputtered AlN film on sapphire substrate by high-temperature annealing

Thermal annealing process of sputtered AlN films with different thicknesses on sapphire substrates was studied in N2 ambient. Crystal quality of these AlN films was significantly improved after 1400–1700 °C annealing. For the 200-nm AlN film, the full width at half maximum (FWHM) of the (0002)-plane X-ray rocking curve (XRC) was improved from 157.3 to 103.6 arcsec after 1650 °C annealing, while the FWHM of the (10 $$\bar {1}$$ 2)-plane XRC was significantly improved from 3890 to 353.1 arcsec. Transmission electron microscopy further confirmed that the crystal quality improvement was related to solid-phase reaction at high temperature, allowing columnar structure AlN to recrystallize and thus reducing threading dislocations in the films. Surface morphology with high-density AlN islands transformed to step-and-terrace morphology. X-ray photoelectron spectroscopy measurement also indicated that C and O impurities were decreased by the thermal annealing process. Film strain changed from tensile to compressive stress after annealing. The optical transmissivities of these AlN films did not decrease after annealing, and the optical transmissivity band edge slopes increased, providing further evidence of improved crystal quality.

System model for physical conditions of road components in Magetan district

Road an important component for a region, as well as for Magetan Regency, its position is located at the end of East Java, making the road infrastructure very useful. For this reason, it is necessary to assess the condition of the pavement and the outer side of the pavement and get results. The assessment model of the national road component condition in Magetan district was developed by adopting a condition index system according to the weight and hierarchy of each road component. The weighting of road components using the Analytical Hierarchy Process (AHP) method through questionnaires resulted in the weight of pavement components 0,80 and for the components outside the pavement of 0.20 with the road shoulder sub component having a weight of 0.37; drainage channel / edge 0.33; edge slopes 0.15; sidewalks of 0.09 and 0.06 and pavement values using the PCI method, where the results of road performance when observed from pavement or out of pavement spawn periodic maintenance.

Effect of Gallium Doping on the Characteristic Properties of Polycrystalline Cadmium Telluride Thin Film

Ga-doped CdTe polycrystalline thin films were successfully electrodeposited on glass/fluorine doped tin oxide substrates from aqueous electrolytes containing cadmium nitrate (Cd(NO3)2·4H2O) and tellurium oxide (TeO2). The effects of different Ga-doping concentrations on the CdTe:Ga coupled with different post-growth treatments were studied by analysing the structural, optical, morphological and electronic properties of the deposited layers using x-ray diffraction (XRD), ultraviolet–visible spectrophotometry, scanning electron microscopy, photoelectrochemical cell measurement and direct-current conductivity test respectively. XRD results show diminishing (111)C CdTe peak above 20 ppm Ga-doping and the appearance of (301)M GaTe diffraction above 50 ppm Ga-doping indicating the formation of two phases; CdTe and GaTe. Although, reductions in the absorption edge slopes were observed above 20 ppm Ga-doping for the as-deposited CdTe:Ga layer, no obvious influence on the energy gap of CdTe films with Ga-doping were detected. Morphologically, reductions in grain size were observed at 50 ppm Ga-doping and above with high pinhole density within the layer. For the as-deposited CdTe:Ga layers, conduction type change from n- to p- were observed at 50 ppm, while the n-type conductivity were retained after post-growth treatment. Highest conductivity was observed at 20 ppm Ga-doping of CdTe. These results are systematically reported in this paper.

Shear wave velocity imaging of landslide debris deposited on an erodible bed and possible movement mechanism for a loess landslide in Jingyang, Xi’an, China

The South Jingyang Plateau, with a total area of 70 km2, is located in Shaanxi Province, China. Since 1976, more than 50 landslides of different types have occurred repeatedly on the edge slopes of the plateau due to the start of diversion irrigation on the plateau, resulting in great loss of lives and property. To better understand the initiation and movement mechanisms of these loess landslides, we surveyed them and carried out a detailed investigation of a large landslide in the Xihetan area. Our field survey results revealed that although most of these landslides had a long runout with high mobility, most of the landslide materials originating from the edge slopes may have been in an unsaturated state when the landslide occurred. This suggests that the materials at the toe of the edge slope as well as on the travel path along the river terrace might have played a key role in landslide movement. To examine how the materials on the travel path were involved in the landsliding, we used a multichannel surface wave technique and surveyed shear wave velocity (V s ) profiles of the landslide deposits. We also examined the internal geometry of the deposits that outcropped on the right-side slope of the landslide foot. The longitudinal profile of V s along the direction of movement showed that terrace deposits near the toe of the edge slope may have been sheared upward, indicating that at the toe, the surface of rupture might be located inside the terrace deposits. The V s contours showed an A-shaped fold within the landslide deposits in the middle part of the travel path and became greater in the most distal toe part. The V s profile across the deposits showed a U-shaped belt, in which the soil layers have smaller V s . This belt may be the boundary between the sliding landslide debris and terrace deposits. The observed internal geometry of the landslide deposits indicates that a sliding surface developed within the sandy layer underlying the gravel layer. Therefore, we inferred that after failure, the displaced landslide materials overrode and sheared the terrace deposits along its main sliding direction, resulting in the formation of thrust folds within the terrace deposits, and greater V s on the distal toe part of the landslide.

Basic geometry and aberration characteristics of conicoidal conformal domes.

This paper investigated the geometry and aberration characteristics of conicoidal conformal domes. First, on the basis of previous research, we got the expression that was suitable for describing the external surface of the conicoidal conformal dome. Based on the theory of differential geometry, this paper first proved that the Dupin index line of a quadric surface was an ellipsoid and the radius of curvature had extreme values in the meridian plane and sagittal plane. Then the uniform formulas of curvature which were suitable for ellipsoid, paraboloid, and hyperboloid were deduced in the meridian plane and sagittal plane, respectively. Meanwhile, the angle between the axis of imaging systems and the surface normal was calculated. With the help of computers, the plots of curvature differences and the angle in the case of different edge slopes, fineness ratios, and the locations of the rotational center were obtained. Finally, we analyzed the Zernike polynomial coefficients of Z4, Z5, and Z8, which represent defocus, astigmatism and coma, respectively for the model established in CODE V. The research indicates that the dynamic ranges of defocus, astigmatism, and coma increase with the growing of edge slopes and fineness ratios, but have little change with the variation of the rotational center positions. Moreover, the curves of Z5 and Z8 have turning points, and the curves of curvature differences and angle difference are only similar to the curves of Z5 and Z8 when the look angle changes after the turning point. For the look angle changing from zero to the turning point, the curves of Z5 and Z8 change rapidly. This is mainly caused by the significant variations of the symmetry of the conformal dome participating in imaging. Therefore, the aberrations with small scanning angles should be given more attention when designing the conformal systems.

Outerplanar graph drawings with few slopes

We consider straight-line outerplanar drawings of outerplanar graphs in which a small number of distinct edge slopes are used, that is, the segments representing edges are parallel to a small number of directions. We prove that Δ−1 edge slopes suffice for every outerplanar graph with maximum degree Δ⩾4. This improves on the previous bound of O(Δ5), which was shown for planar partial 3-trees, a superclass of outerplanar graphs. The bound is tight: for every Δ⩾4 there is an outerplanar graph with maximum degree Δ that requires at least Δ−1 distinct edge slopes in an outerplanar straight-line drawing.

ENGINEERING GEODYNAMICS OF LANDSLIDE SLOPES OF THE ODESSA SEA COAST AFTER ANTI-LANDSLIDE MEASURES

A general characteristics is made of the set of anti-landslide measures at the Odessa sea coast. Based on multi-year regime observations over the operational efficiency of anti-landslide constructions, it is shown that the modern geodynamics of landslide slopes is determined by the combination and relationships of various factors. The most important factors are: micro-block structure of the plateau edge and landside slopes, high sensitivity, mobility and changeability of properties of the geological environment.

Investigation of analog charge multiplexing schemes for SiPM based PET block detectors

Reducing the number of output channels in pixelated positron emission tomography (PET) detectors is an effective way to minimize cost and complexity while minimizing the impact on detector performance. This paper compares the system performance of two multiplexing schemes by using both simulation and experimental studies, with respect to spatial, time and energy resolutions. Simulations were performed using the SPICE environment to investigate differences in resulting flood histograms and rising edge slopes. Experiments were performed using lutetium-yttrium oxyorthosilicate (LYSO) crystals coupled to a SensL ArraySL-4 silicon photomultiplier (SiPM) connected to interchangeable circuit boards containing the two multiplexing schemes of interest. Three crystal configurations were tested: a single crystal element (3×3×20 mm3), 2×2 array (crystal pitch: 3×3×20 mm3) and 6×6 array (crystal pitch: 2.1×2.1×20 mm3). Good agreement was found between the simulations and experiment results. It is found that the capacitive multiplexing is able to achieve an improved time resolution of good uniformity (average of 1.11 ± 0.01 ns and 1.90 ± 0.03 ns for the arrays, respectively) and crystal separation, compared to the resistive multiplexing (average of 1.95 ± 0.03 ns and 3.33 ± 0.10 ns). On the other hand, the resistive multiplexing demonstrates slightly improved energy resolution (11 ± 0.1% and 22 ± 0.6%, compared to 12 ± 0.1% and 24 ± 0.4% for the capacitive array), which is believed to be caused by the RC circuit formed between the splitting capacitors and the input impedance of amplifiers. The relevancy of this work to the PET block detector design using SiPM arrays is also discussed, including light sharing, edge compression and gain variation among SiPM pixels.

Femtosecond laser writing of optical edge filters in fused silica optical waveguides

The positional alignment of femtosecond laser written Bragg grating waveguides within standard and coreless optical fiber has been exploited to vary symmetry and open strong optical coupling to a high density of asymmetric cladding modes. This coupling was further intensified with tight focusing of the laser pulses through an oil-immersion lens to control mode size against an asymmetric refractive index profile. By extending this Bragg grating waveguide writing into bulk fused silica glass, strong coupling to a continuum of radiation-like modes facilitated a significant broadening to over hundreds of nanometers bandwidth that blended into the narrow Bragg resonance to form into a strongly isolating (43 dB) optical edge filter. This Bragg resonance defined exceptionally steep edge slopes of 136 dB/nm and 185 dB/nm for unpolarized and linearly polarized light, respectively, that were tunable through the 1450 nm to 1550 nm telecommunication band.

Late Neogene chronology and sequence stratigraphy of mixed carbonate-siliciclastic deposits of the Cibao Basin, Dominican Republic

A stratigraphic study of late Miocene–Pliocene mixed carbonate and siliciclastic sediment (upper part of the Yaque Group) was conducted in northern Hispaniola to refine the chronostratigraphy of uplifted, nearshore marine sequences in the Cibao Basin. Classic late Neogene sections in these sequences include a spectacularly preserved faunal record for the northern Caribbean. Refined ages of the Cercado Formation (6.6–6.0 Ma), the Gurabo Formation (ca. 5.8–4.0 Ma), and the Mao Formation (3.9–3.5 Ma) allow correlation to regional and global sea-level events. Each of the three formations corresponds to one depositional sequence, composed of mixtures, at different proportions, of skeletal debris, mostly coral, and mud-size (silt) siliciclastic sediment. Distinct stratal geometries and lithofacies individualize the three formations, each separated by pebble conglomerates. The Cercado Formation depositional sequence consists of prograding inner-shelf siliciclastic sands and patch reefs. The basal transgressive unit of the Gurabo Formation is made of seaward-prograding low-angle clinothems of bedded and burrowed siliciclastic sand with molluscs and free-living corals. The upper Gurabo unit consists of massive middle-shelf clinothems of silt with bedded reef debris and in situ branching coral thickets. These clinothems grade basinward into massive, deeper-water silt deposits at the shelf edge and basin slopes. The Mao Formation sequence records the transition from lowstand fluvial-deltaic facies to transgressive and highstand marine clinothems made mostly of coral debris in a silt matrix. In the Mao Formation outcrops, the coral-silt clinothems can be divided into at least 10 high-frequency cycles (40 k.y.?) based on lithofacies. Channelized and slumped coarse siliciclastic sand, gravel, and nonmarine alluvium cap the sequence, likely associated with lowered sea level starting at ca. 3.3 Ma and perhaps the onset of regional uplift. The major lithologic and sequence geometry changes in the Cibao Basin correlate with trends in the oxygen isotope ice-volume proxy and likely reflect deposition responding to major periods of marine transgression and highstand. An especially prominent feature is the major deepening and margin back step near the Miocene–Pliocene boundary, continuing in the early Pliocene, which resulted in the deposition of the Gurabo Formation. Transgression and sea-level highstand in the late–early Pliocene (3.9–3.5 Ma) produced distinctive margin progradation primarily by coral debris. This progradation event was synchronous with progradation in the nearby western Great Bahama Bank. The different stratal configurations of the three sequences can be attributed to a combination of factors, including: (1) shelf morphology and location on the shelf, (2) paleoceanographic conditions such as warm sea-surface temperatures and reduced upwelling, which controlled coral productivity and reef geometry, and (3) the influx of siliciclastic mud from the adjacent mountains.