Academic literature on the topic 'Onion Creek'

The fish of Thane Creek and Ulhas River Estuary are contaminated with mercury. The traditional fishing folks residing along these water sources consume large amounts of these fish for their sustenance, therefore, being vulnerable to mercury poisoning. A survey on the clinical signs and symptoms of mercury poisoning was carried out in Wehele, Alimgarh and Diwe-Kewni along Ulhas River Estuary and Vittawa and Airoli along Thane creek. Fortunately, no alarming signals of mercury poisoning could be detected in these populations. Genetic make-up and/or use of onion and garlic in the fish preparations could be the probable detoxifying factors in these populations. However, these populations being vulnerable to mercury poisoning, continuous monitoring is recommended in these areas. This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

The Onion Creek diapir is one of the best exposures of a dissected salt diapir in the world, offering a unique opportunity to better understand the internal character of heterolithic diapirs that are common in sedimentary basins worldwide. Large amounts of interbedded shale, carbonate, and evaporites are incorporated into the diapir as stringers or boudins, and excellent three-dimensional exposure allows us to document the nature, size, deformation, and distribution of these stringers. Blocks range in size from single, disaggregated layers of dolomite to several meters of coherent stringers that contain multiple cycles of dolomite- shale-evaporite and are upwards of 20 m thick and more than 100 m in observed length. The largest blocks are most commonly located along the margins of the exposed diapir, though stringers are common throughout the exposed caprock. In areas devoid of large stringers, there is more extensive deformation of the gypsum caprock, suggesting that the presence of stringers leads to a more heterolithic distribution of stress within the salt as it diapirically rises. These observations can help to better characterize similar diapirs elsewhere that are not well exposed at the surface. Black shale is present in all observed large stringers of the Onion Creek diapir. These shale beds are interpreted to have been deposited in a shallow, restricted marginal marine environment along with the interbedded carbonate and evaporite strata. Pyrolysis analysis of 13 samples from within the stringers shows a range of 2.56 to 60.22% total organic carbon (TOC), with an average value of 16.93%. These strata contain Type I/Type II hydrocarbon source facies, consistent with a restricted shallow marine environment. Tmax data suggest that these source rock facies have been exposed to sufficient thermal energy to generate hydrocarbons (average = 437o C), as evidenced by common hydrocarbon staining of intra-stringer carbonate strata and evaporite beds surrounding the stringers. Twelve additional samples were collected from these stained strata and pyrolysis analysis shows that all are enriched in free oil, as shown by elevated S1 peaks, high production index ratios, and TOC values of 0.64 to 1.66%. This hydrocarbon staining is found around stringers near the center of the exposed caprock, as well as stringers along the margins. Near the margins in particular, extensive alteration can be seen across tens of meters of evaporitic strata, showing that hydrocarbons are effectively generating within and migrating away from stringers fully encased in the anhydrite caprock of the Onion Creek diapir. This has important implications for potential seal integrity of diapiric caprocks, as well as providing a potential mechanism for caprock carbonate formation suggested by other researchers.

The Onion Creek diapir is one of the best exposures of a dissected salt diapir in the world, offering a unique opportunity to better understand the internal character of heterolithic diapirs that are common in sedimentary basins worldwide. Large amounts of interbedded shale, carbonate, and evaporites are incorporated into the diapir as stringers or boudins, and excellent three-dimensional exposure allows us to document the nature, size, deformation, and distribution of these stringers. Blocks range in size from single, disaggregated layers of dolomite to several meters of coherent stringers that contain multiple cycles of dolomite- shale-evaporite and are upwards of 20 m thick and more than 100 m in observed length. The largest blocks are most commonly located along the margins of the exposed diapir, though stringers are common throughout the exposed caprock. In areas devoid of large stringers, there is more extensive deformation of the gypsum caprock, suggesting that the presence of stringers leads to a more heterolithic distribution of stress within the salt as it diapirically rises. These observations can help to better characterize similar diapirs elsewhere that are not well exposed at the surface. Black shale is present in all observed large stringers of the Onion Creek diapir. These shale beds are interpreted to have been deposited in a shallow, restricted marginal marine environment along with the interbedded carbonate and evaporite strata. Pyrolysis analysis of 13 samples from within the stringers shows a range of 2.56 to 60.22% total organic carbon (TOC), with an average value of 16.93%. These strata contain Type I/Type II hydrocarbon source facies, consistent with a restricted shallow marine environment. Tmax data suggest that these source rock facies have been exposed to sufficient thermal energy to generate hydrocarbons (average = 437o C), as evidenced by common hydrocarbon staining of intra-stringer carbonate strata and evaporite beds surrounding the stringers. Twelve additional samples were collected from these stained strata and pyrolysis analysis shows that all are enriched in free oil, as shown by elevated S1 peaks, high production index ratios, and TOC values of 0.64 to 1.66%. This hydrocarbon staining is found around stringers near the center of the exposed caprock, as well as stringers along the margins. Near the margins in particular, extensive alteration can be seen across tens of meters of evaporitic strata, showing that hydrocarbons are effectively generating within and migrating away from stringers fully encased in the anhydrite caprock of the Onion Creek diapir. This has important implications for potential seal integrity of diapiric caprocks, as well as providing a potential mechanism for caprock carbonate formation suggested by other researchers.

Abstract As an arts-based, creative storytelling program for persons living with Alzheimer’s Disease and related dementias (ADRD), TimeSlips involves a facilitator showing a picture to participants, who then exercise their imagination to create a story. The program has shown to benefit participants’ well-being, possibly because of the opportunity to express themselves. Although they may reflect participants’ values and identities, the content of such stories had not been the focus of investigation. The aim of this study is, therefore, to identify major themes of such stories through a qualitative content analysis. We implemented a creative storytelling program at Silverado Onion Creek Memory Care Community (currently, The Auberge) in Austin, and offered 6 weekly sessions with 4 small groups of residents. A total of 26 residents participated in the study, creating 24 collective stories in total. Three researchers first open-coded these stories and then met to reach consensus concerning the themes that emerged. Ten themes were identified: family values, generativity, religious reference, reference to love, reference to home, cultural norms, uncertainty and worries, positivity, negativity, and dissonance and disagreements. The first 6 themes represent the values, beliefs, and norms of the participants, with the remaining 4 reflecting their personal identities, personalities, and experiences. The findings suggest that they continue to value families and religion, care about others, and make judgements about people, things, and circumstances that they face. Researchers, practitioners, and care partners can benefit from “listening to” creative storytellers more closely to learn about their opinions, expectations, and preferences.

Abstract Considering healthcare costs related to Alzheimer’s Disease and related dementias, shifting attention to the relatively malleable abilities of persons living with dementia holds promise for improving their well-being while reducing care burden. Defined as the ability to successfully interact with others, social intelligence is found to benefit well-being. Nevertheless, no known prior study has examined social intelligence among persons living with dementia. The purpose of this study is, therefore, to fill this gap by identifying the themes of social intelligence in this group. We used video-recorded data from an arts-based, creative group storytelling program (TimeSlips) that we implemented at Silverado Onion Creek Memory Care Community (currently, The Auberge) in Austin. The program is designed for persons living with dementia and involves a facilitator encouraging participants to use their imagination to collectively create a story from a staged picture. We offered 6 weekly sessions with 4 small groups of their residents (N = 26) in fall 2018 and spring 2019, and videotaped the sessions. Three researchers open-coded how participants interacted during storytelling sessions, and then met to reach consensus concerning verbal and non-verbal indicators of social intelligence. Major themes that emerged from our analysis are social awareness, initiating social interactions, and social diplomacy. Our findings suggest that those with lower cognitive function scores do not necessarily lack sociability. These findings add to social intelligence and dementia literatures, with potential implications for future research that can investigate the relationship between sociability and well-being among persons living with dementia.

Abstract De-esterification of homogalacturonan (HG) is thought to stiffen pectin gels and primary cell walls by increasing calcium cross-linking between HG chains. Contrary to this idea, recent studies found that HG de-esterification correlated with reduced stiffness of living tissues, measured by surface indentation. The physical basis of such apparent wall softening is unclear, but possibly involves complex biological responses to HG modification. To assess the direct physical consequences of HG de-esterification on wall mechanics without such complications, we treated isolated onion (Allium cepa) epidermal walls with pectin methylesterase (PME) and assessed wall biomechanics with indentation and tensile tests. In nanoindentation assays, PME action softened the wall (reduced the indentation modulus). In tensile force/extension assays, PME increased plasticity, but not elasticity. These softening effects are attributed, at least in part, to increased electrostatic repulsion and swelling of the wall after PME treatment. Despite softening and swelling upon HG de-esterification, PME treatment alone failed to induce cell wall creep. Instead, acid-induced creep, mediated by endogenous α-expansin, was reduced. We conclude that HG de-esterification physically softens the onion wall, yet reduces expansin-mediated wall extensibility.

Summary New methods have been developed to constrain optimal horizontal drilling distance in fractured reservoirs in which opening-mode fractures are dominant. Studies of opening-mode fractures in Austin Chalk outcrops and core reveal that open fractures are commonly clustered, with the distance between clusters ranging from approximately 1 m to more than 300 m, depending on the horizon in question. Aperture-size distributions follow power laws, and spacing-size distributions are negative logarithmic or log-normal. The aperture size at which fractures are open to fluids is variable and site-specific (0.14 to 11 mm). Scaling properties of fracture attributes were used to calculate fracture permeability and to constrain well-length fracture-permeability relationships. Fracture permeability depends on the scale of measurement; it has been determined at 9.2 darcies for 14 m of lower Austin Chalk core and 286 darcies for 300 m of upper Austin Chalk outcrop. Introduction The Upper Cretaceous Austin Chalk, which crops out in a swath across central Texas, is renowned as a horizontal play and is well documented as such.1,2 Most workers regard Austin Chalk reservoirs as being low-porosity, fractured reservoirs, although there is debate concerning the relative storage capacities of matrix vs. fractures. When drilling a horizontal well in a fractured reservoir, the usual aim is to intersect fractures that are capable of providing a conduit for fluid flow. Although many horizontal wells have been drilled in the Austin Chalk,3 there are still questions over where it is best to locate new operations and how to optimize three critical parameters: wellbore azimuth, vertical depth, and wellbore length.4 This paper focuses on the question of wellbore length, although information pertaining to azimuth and depth choices also has been obtained. The choice of wellbore length has, in the past, been guided by experience and by field rules established by the Texas Railroad Commission, whereby the length of wells is linked to the acreage allocation of proration units and the permissible producing rate.4 Although these guidelines are practical, they lack direct geological input. The aim of this contribution is to develop techniques in which well-length determination is based on direct observation of fracture systems in the Austin Chalk, in addition to the Texas Railroad Commission guidelines. The objective of the outcrop and core studies was to characterize the opening-mode fracture system. Aperture-size distribution, spacing-size distribution, and fracture fill were determined in each case, allowing characterization of the spatial architecture of large, open fractures. This approach enabled us to calculate fracture permeability for different well lengths and to constrain optimal drilling distance for horizontal wells. The relationship between opening-mode fractures and normal faults in the outcrop is documented, and the relative importance of fractures and faults to reservoir permeability is considered. The connectivity and vertical height of fractures, and their impact on permeability, are discussed. Study Areas Data are presented from two outcrop analogs: one is near Waxahachie, north central Texas (Grove Creek); the other is from McKinney Falls State Park, central Texas (McKinney Falls), and from two laterals of a horizontal core drilled by the Kinlaw Oil Corp. in Frio County, Pearsall field (Kinlaw core) (Fig. 1). This well is currently operated by BASA Resources Inc. Although this study relates to the Austin Chalk specifically, the techniques used are transferable and could be applied in other horizontal targets. Geology The Austin Chalk is variable in terms of mineralogy, texture, and stratigraphy in part because of the effect of a basement high, the San Marcos Arch,5 on the paleobathymetry of its depositional basin. The updip portions of the Chalk in the Austin and San Antonio regions are relatively shallow water deposits containing considerable quantities of benthic skeletal material. Deeper-water planktonic microfossils and nanofossils dominate the basin equivalents, although some benthic material was transported basinward in debris flows.5 Drake6 reports the updip portions of the chalk in Burleson County, Giddings field, to be less fractured than the downdip portions, with wells in the updip portions being poor producers. At McKinney Falls State Park, a pavement in the McKown formation is exposed where Onion Creek flows over the lower falls. The McKown formation is a lateral equivalent of the Austin Chalk and comprises chalk intercalated with pyroclastic deposits derived from Pilot Knob, a Cretaceous volcanic center 3 km to the southeast.7 The Grove Creek outcrop is stratigraphically at the top of the Upper Chalk, just below the overlying Ozan formation. The McKinney Falls outcrop is close to the overlying Taylor Marl. The horizontal Kinlaw core from Pearsall field is from the base of the lower Chalk in the Atco Member. Thus, stratigraphically and with respect to the basin architecture, the studied sites are disparate. It is not the intention of this paper to make definitive recommendations for drilling distance in the Austin Chalk based on so few sites, but rather to show with these examples how site-specific information may be used to this end. Data-Collection Methodology An important consideration in fracture studies is whether the fractures observed in a particular core or outcrop are representative of those fractures that occur in the subsurface and contribute to fluid flow. In the case of core studies, the main pitfalls surround the distinction of natural fractures from those induced by drilling or by the core-handling process. Kulander et al.8 provided a comprehensive guide to natural and induced fracture identification in cores, and their criteria were used here. In outcrop studies, the challenge is to distinguish those fractures that would have been formed in the subsurface, at an appropriate depth to be considered as a reservoir analog, from those fractures that developed during uplift and erosion. The fracture systems documented here are confined to those that exhibit partial or total mineral fill and that would have developed in the subsurface.

The Onion Creek Diapir is one of many salt domes proximal to the Uncompahgre thrust front of the ancestral rockies in the Paradox Basin. It is comprised of Paradox Formation evaporites and large blocks of Honaker Trail Formation carbonates that were deformed by loading of Permian Cutler Formation progradational alluvial to fluvial fans. The history of salt movement in the Onion Creek Diapir is recorded in the near-salt strata. Large salt bodies and their adjacent mini-basins evolve conforming to a complex relationship between salt withdrawal, creating localized accommodation, and sediment deposition. Migrating mini-basin depo-centers, thinned and folded strata, and spatial facies trends reveal the relative rates of diapirism and sedimentation. The study area outcrop, north of the diapir, is divided by significant stratigraphic horizons that help define depositional periods. Six measured sections in the study area reveal higher preservation rates of fine grained floodplain deposits, typically destroyed in alluvial environments, than at locations correlating to stratigraphic levels high in the outcrop suggesting a low accommodation environment evolving into higher accommodation where stacked channel complexes are preserved. Preserved slump folding at the base of the outcrop reveals that although some salt emergence occurred in the earliest depositional period it was not significant enough to preclude sediment deposition or to divert the Cutler fluvial network and destroy floodplain facies. A 3-D digital outcrop, modeled from photogrammetric data, illustrates the development of localized accommodation, attracting fluvial channel in a near-salt, tight axial syncline during the later depositional period. These evidences suggest a greater emergence of the diapir and likely diversion of the Cutler channel complexes.

It is an uncommon gift to have a mountain to yourself. Pulling up to the trailhead for the Bell Mountain Wilderness Area, I saw no other vehicles parked there and began to hope for as much. I noticed that the dirt road into the area hadn’t been graded recently. Another good sign was my having to wipe spider webs from my face every hundred yards or so as I hit the trail. Obviously no one had been there for a while. But the real treat was reaching the top of the mountain and finding nothing. A favorite campsite lay empty, nestled in the rocks just above the treetops. From there you can look out onto thousands of acres of oak- and hickory-covered hills to the east. Not a road or a building in sight, nothing but trees. Bell Mountain is one of eight protected wilderness areas in Missouri. It is named after a family that once lived and farmed along its 1,700-foot ridge. I’d gotten a late start that day and the sun was going down by the time I set up camp. But sunlight on a late April afternoon, filtered through the yellow-green growth of new leaves, can be stunning. I sat on a rock ledge, cutting up potatoes, onions, and carrots for mulligan stew, watching shadows creep up the hills across the hollow. Putting the vegetables in a pot, I added fresh basil and rosemary, topped it off with ground beef, and washed it down with a shot of Grand Marnier as night came on. I delight in the solitude of these trips, but I’m not always sworn to a monastic austerity. Bell Mountain is a good place for the study and practice of solitude. I’ve sat there for hours with only the dog beside me, watching red-tailed hawks and turkey vultures soar on thermals rising from the forest below. Now and then you’ll see a lone eagle high overhead, though generally they nest closer to the river. Bald eagles are common in Missouri, especially in winter.