“Captorhinikos” chozaensis is a multiple-tooth-rowed captorhinid reptile from the Lower Permian Clear Fork Group, undivided formation. Upon re-examination of the materials associated with the species from both the Chicago Field Museum of Natural History, and the Smithsonian United States National Museum, I reaffirm their affinity and collective identity as a valid taxon. “Captorhinikos” chozaensis does not, however, belong with either of the two members of its genus, C. valensis or “C.” parvus, instead occupying its own branch on the phylogenetic tree of the Captorhinidae. This conclusion is based in strong results from a combined phylogenetic parsimony analysis combined with an analytical apomorphy analysis. I then conclude the current designation “Captorhinikos” chozaensis to be a nomen ambiguum.

Sclerochronology was conducted on the pedicle valves of four Sakmarian-age brachiopods (Squamaria moorei) to constrain climate model predictions of temperature seasonality along western equatorial Pangaea (WEP). The brachiopods are from a Lower Permian section within the Robledo Mountains, NM, and they reveal seasonal trends of δ18O and temperature for that interval that suggest global warming and moderation of seasonality. Elemental and SEM analyses verified the specimens were well preserved. δ18O profiles show a relatively rapid and consistent two-year growth rate corresponding to the organism's juvenile stage, followed by a slower, seasonal growth rate corresponding to the organism's sexually mature stage typical of most organismal growth. Their initial two-year cycles show consistent, high-amplitude profiles that captured virtually complete records of annual δ18O values, and these profiles were used for seasonality interpretations. The specimen from the stratigraphically lowest layer shows δ18O values varying from -4.26 to -2.17 minimum winter temperatures (MWT) and maximum summer temperatures (MST) of 25.2C and 35.7C, respectively; and a seasonal temperature variation ΔTs of 10.0C. The overlying horizon yielded two specimens showing δ18O values ranging from a minimum of -4.54 to a maximum of -2.79; MWT ranging from 28.2 to 29.6C; MST ranging from 34.9 to 37.2C; and ΔTs ranging from 6.7 to 7.6C. The uppermost layer yielded a specimen that shows δ18O values ranging from -4.49 to -3.03; MWT of 31.3C; MST of 37.0C; and ΔTs of 5.7C. The specimens show overall high seasonality for an equatorial regime, but the general trend shows increasing winter temperatures and a moderation of seasonality. The data supports climate-model predictions for the Permian of more equable temperatures, higher winter temperatures, and decreased seasonality. Three numerical climate models of Permian temperatures were evaluated against the brachiopod data, and their model predictions for ΔTs along WEP range from as high as 10C to as low as C. The models were supported somewhat by the independently derived temperature proxy data measured in this study.

No description available.

The aim of this study is to designate paleontologic, biostratigraphic and sequence stratigraphic characteristics of the Permian-Triassic Boundary beds of the Bolkar Dagi Unit in the Hadim region (Central Taurides). For this purpose a 48,06m thick stratigraphic section, composed of limestone, siltstone and sandstone, was measured and 116 samples were analyzed through the Permian Ta

Outcrops of the Abo Formation (Wolfcampian to early Leonardian age) in the Sacramento Mountains of south-central New Mexico record the evolution of a dry alluvial fan system as it was deposited off of the Pedernal Uplift into the Orogrande Basin. A mud-rich, upward-fining basin-fill sequence characterized by stratigraphic thickness variations of as much as 450 m (1480 ft) and contacts that range from conformable to unconformable relationships is observed in the outcrop area. Five distinctive lithologic intervals are delineated in the Sacramento Mountains, three of which are studied in detail. These three units are informally designated the lower, middle, and upper Abo intervals and are all fluvial in origin. The remaining two intervals, the Lee Ranch Tongue of the Abo Formation and the Pendejo Tongue of the Hueco Limestone, are marginal marine in origin and are restricted to the southern portion of the range. Two types of lithofacies are present in the lower, middle, and upper Abo intervals. Matrix facies represent fine-grained overbank sediments, whereas framework facies represent coarser streamflow and sheetflow deposits. Lower Abo framework facies consist of middle-fan to fan-fringe stream-channel, braided stream, and sheetflood deposits which are arranged in one or more stacked, assymetrical, upward-fining megasequences 10-50 m (33-165 ft) in thickness. Middle and upper Abo framework facies were deposited basinward of the fans and represent deposits of incised, low to moderate sinuosity ephemeral streams and associated overbank splays. Middle Abo streams exhibited an anastomosed channel pattern whereas upper Abo channels were characterized by a distributive pattern. Pedogenic and sedimentologic evidence suggests that Abo deposition was strongly influenced by a long term, semi-arid to arid climate. Lateral and vertical facies relationships indicate that the five Abo intervals were part of a northeast to southwest transverse facies tract consisting of 1) proximal alluvial fans, 2) medial anastomosed streams, and 3) distal low-gradient mud-dominated floodbasins characterized by either distributary streams or tidal flats with associated marine carbonates. The overall Abo basin-fill sequence reflects the migration of the facies tract in response to the final stages of tectonic activity and the eventual quiescence and long-term erosion, retreat (pedimentation), and onlap of the Pedernal Uplift. / text

Ooid grainstone reservoir architecture remains poorly understood, particularly because of sedimentologic and stratigraphic heterogeneities that are innate to grainstone body development. Understanding of Geospatial relationships and recovery of hydrocarbons from these significant reservoir facies can be improved with access to outcrop analog information from well exposed examples. Object-based models and other modern subsurface reservoir models are considered superior methods for portraying realistic sediment distributions. These models, however, are highly dependent on input data describing sediment-body geometry for faithful template generation. Such input data are notably rare in carbonate systems. Maps generated from modern depositional patterns give a first approximation of areal distribution, but they are not as useful for understanding final preserved stratigraphic thickness and internal facies, sedimentary structure, and grain-type patterns. For this purpose, studies of exceptional outcrops are required. The 18 km long oblique-dip-oriented wall of the Shattuck Escarpment provides such a unique exposure of Permian-age grainstones. The Shattuck Escarpment in the Guadalupe Mountains provides an oblique-dip profile that exposes a near-complete middle Permian Grayburg mixed clastic-carbonate shelf succession of three high-frequency sequences which contain 30 high-frequency cycles. Particularly important for this study are the four cycles that display full updip to downdip extents of ooid grainstone tidal bar and tidal delta objects. The data from the Shattuck wall presented in this paper focusses on the transgressive portion of the upper Grayburg, or G12 high-frequency sequence (HFS), located 5 km landward of the time-equivalent shelf margin. This interval is an analog for productive fields along the northwest shelf of the Delaware Basin and on the eastern flank of the Central Basin Platform. The goal of this project is to understand the sedimentology and facies/cycle architectural variability of tidally influenced shelf crest ooid grainstones of the Grayburg Formation. Comparing this outcrop data to modern grainstone deposits allows the reader to understand the small-scale and large-scale sedimentologic and architectural patterns in analogous subsurface ooid grainstone reservoirs. Spatial analysis of these cycles was carried out using measured sections and GigaPan (high resolution photomosaic) data. Petrophysical (Porosity and Permeability) data was collected from three separate vertical core plug transects approximately 1 km apart with a vertical resolution of 30 cm. Cycle-set-scale grainstone complexes up to 6m thick extend at least 4.25 km along depositional dip and show variations in permeability between 6-400 mD and porosities between 8-20% within the lower portions of the grainstone complex. / text

The eastern side of the Guadalupe Mountains, located in New Mexico and west Texas, represents an erosional profile along the Capitan reef margin. A complete shelf-to-basin exposure of the Upper Permian Capitan shelf margin is found on the north wall of North McKittrick Canyon, which is nearly perpendicular to the Capitan reef margin. An excellent 2-D sequence stratigraphic framework for upper Permian backreef facies has been developed by previous workers for North McKittrick Canyon (Tinker, 1998) and Slaughter Canyon (Osleger, 1998), forming the basis for observations in this study. The goal of this study is to describe the sequence stratigraphic architecture of the Yates Formation, focusing on the Y4-Y6 high-frequency sequences (HFSs) found in the middle to outer shelf depositional systems, and to illustrate the use of airborne lidar data to quantitatively map at the cycle-scale. Seven measured sections were taken in North McKittrick Canyon. From airborne lidar, 3-D geometries of key sedimentary and structural features were mapped in Polyworks, in addition to the sequence boundaries delineating the Yates 4-6 HFSs. In general, major cycles exhibit asymmetry and shoal upward. Cycle boundaries are sometimes hard to delineate due to amalgamation, particularly in the shelf crest. High-frequency sequences are commonly asymmetric; they deepen and thicken upward toward the maximum flooding surface, and the boundaries between HFSs are usually marked by thick siltstones. Major HFS boundaries can be mapped across the entire dataset, and some component cycles can be observed for minimum distances of one kilometer in an updip-downdip direction. Also, some facies tract dimensions can be estimated directly from the lidar data. Measured sections indicate that the shelf crest facies tract shifts seaward with each successive HFS, while the outer shelf facies tract steps landward. Future work that could be done with the Y4-Y6 HFSs includes 8-10 more measured sections, collection of samples for thin sections, and tracing out of contacts between facies tracts. Extensive lidar data interpretation needs to be done so that digital outcrop models demonstrating facies distributions can be produced. This would enable the development of an outcrop analog model to mixed carbonate-siliciclastic reservoirs, which would be unprecedented in this area. / text

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No description available.

The Lysorophia is an order of small, but extremely elongate and tiny-limbed aquatic lepospondyl amphibians existing from the Middle Pennsylvanian through the Lower Permian, primarily in North America. The order comprises one family, Cocytinidae, with three recognized species: Brachydectes newberryi (=Cocytinus gyrinoides), B. elongatus (=Lysorophus tricarinatus, partim) and Pleuroptyx clavatus. Other named species are considered Lysorophia, incertae sedis. Lysorophoids are distinguished by their fenestrated skulls, anteriorly sloping suspensoria, short mandibles (each bearing a lateral mandibular fenestra) and by extensive, well-ossified hyobranchial skeletons. Presacral vertebrae are holospondylous and number between 69 (B. newberryi) and 97 (B. elongatus). Neural arch halves are sutured at their midlines and to their centra. Aspects of lysorophoid anatomy, including the hyobranchial skeleton, suggest that the lysorophoids are neotenic. / While closely similar to one another, lysorophoid species are highly derived relative to other Paleozoic amphibians. They are most closely related to microsaurs, principally through the morphology of the craniovertebral articulation.