Tracing Echoes between Tides: Drawing, listening, sounding

Runoff generation and erosion processes at the rock–soil interface of outcrops with a concave surface in a rocky desertification area

This paper was prepared for the 48th Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Las Vegas, Nev., Sept. 30-Oct. 3, 1973. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgement of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines. Abstract This study deals with rotary high pressure jet parameters and the effect of nozzle geometry on the shape and performance of the jet. Pressures up to 15000 psi (1.55 kg/cm2) have been Pressures up to 15000 psi (1.55 kg/cm2) have been used with rock samples rotating from 150 to 300 r.p.m. and with the bottom-hole depth simulated up to 5000 ft. The effect of multi-jet reaction on rock surfaces is presented together with a general relationship for the depth of cut produced by a high pressure jet on the rock surface. Introduction High pressure jet drilling recently received considerable attention, as an effective method for oil well drilling, and the field tests of high pressure drilling gave successful results. High pressure drilling gave successful results. High pressure jet drilling outperforms rotary drilling pressure jet drilling outperforms rotary drilling because it transfers 80 to 90% of the available surface horsepower to the bottom of the hole for rock penetration, while rotary drilling transfers a maximum of 5 percent of the rig power to the drill bit. In rotary drilling the rest of the rig power either lays idle for tripping the drilling string or is consumed in friction and in circulating the drill cuttings from the bottom of the hole to the shaleshaker. Summers, Maurer, and others have investigated the relation between the crater formed by a high pressure water jet and the nozzle parameters, but most of the previous work has been done with a static nozzle for a prolonged time (0.5 - 30 seconds) under atmospheric prolonged time (0.5 - 30 seconds) under atmospheric conditions. In oil well drilling the jet action on the rock is in the order of milliseconds. The operation parameters of the static jet are completely different from the rotating jet due to the type of reflection surface and the amount of jet interference. The works of Cunningham and Eenin, Maurer and Eckel indicate the effect of down hole pressures on rock drillibility with conventional cutting edges. The failure of rock at depth under a rotary high pressure jet has not been investigated before. pressure jet has not been investigated before. Albertson, Eckel, and Farmer investigated fluid flow through different nozzle geometries. The investigations were mainly theoretical and the experimental part of their work was not within the operating pressures of high pressure jet drilling.

Water is an essential resource for the existence of life on earth. The storage capacity of the water depends on the physiography, soil, slope and geomorphic characteristics of the region. The analysis of geomorphic indices can signify the relationship between topographic characteristic and water retaining capacity which helps in identifying the water shortage problem and its solution. Most of the coastal watersheds in Deccan trap region in India face water scarcity problem during non-monsoonal season as they are covered mostly by basaltic hard rock terrain which is less porous in nature. The main focus of the present research is the analysis of geomorphic indices to address the water retaining problem and to suggest water resource management plan through integrated Remote Sensing and GIS techniques. To achieve this goal, the spatial data has been collected from different sources which is incorporated with field observation data. The thematic databases such as geology and geomorphology have been prepared to understand the topographical characteristic of the study area. The various geomorphic indices have been quantified with the help of satellite image and ASTER GDEM in GIS platform. The comparative geomorphic indices curves have been prepared to understand the topographic and geomorphic factors for addressing the water recharge problems. The analysis of geomorphic indices shows that the water retaining capacity is very low in the Upper gad and Janvali sub-watershed due to the influence of hard (Basaltic) rock, steep slope and has greater structural control. Further, hard rock terrain, rugged topography and surface roughness have been observed during field study which has great influence on water retaining capacity. The suitable artificial recharge techniques have also been suggested for sustainable development of water resource in the study area.

The atmosphere of Venus is predominately composed of CO2, with minor amounts of N2, H2O and SO2 (e.g. Fegley 2014). This combination of gases, in conjunction with a high surface temperature (~460 °C), means that the weathering processes on Venus are very distinct from Earth. Information about the surface composition of Venus have been obtained thanks to the Venera and Vega missions (e.g. Surkov et al. 1986) which indicate that Venus is comprised of basaltic rocks very similar to terrestrial compositions (e.g. Treiman 2007). As such, numerous weathering experiments and modelling attempts of basalts under Venusian or near-Venusian atmospheric conditions have been conducted (see Filiberto and McCanta 2024) with multiple studies showing that calcite (CaCO3) and anhydrite (CaSO4) can form on the surface of basalts as a result of gas-rock interactions (e.g. Semprich et al. 2020, Reid et al. 2024; Renggli et al. 2020). The abundance of these minerals is dependent on time, thereby providing constraints on the timing of volcanic activity on Venus. Accurately identifying how recently Venus was volcanically active is important to understanding not only how Venus has evolved, but to put our own planet, the Earth, and Earth-like exoplanets in a global planetary context (e.g. Widemann et al. 2023). Analysing these weathering features and compositional differences on Venus will be achievable with the EnVision (ESA) and VERITAS (NASA) orbiters, which are set to launch in the 2030’s (Ghail et al. 2012; Smrekar et al. 2022). Both of these orbiters will be equipped with a suite of spectroscopic instruments (including VenSpec-M and the Venus Emissivity Mapper, respectively) that will be capable of analysing the surface within the near-infrared (NIR) spectral range between 0.86 and 1.18 μm (e.g. Smrekar et al. 2022). As such, the aim of this work is to understand how the proportions of calcite and anhydrite will affect the emissivity spectra of basalt under near-Venus surface conditions. This will be achieved through a series of mixtures that simulate the varying degrees of weathering observable on Venus by changing the total surface area coverage of each component. The Planetary Spectroscopy Laboratory (PSL, DLR in Berlin) is uniquely equipped with an emissivity chamber that can analyse emissivity spectra under Venus temperatures (~460 °C) and near-vacuum conditions (~0.7 mbar), thus allowing analogue samples to be studied under similar conditions that will be encountered by the EnVision and VERITAS orbiters. Figure (1): sample mixtures before (left samples) and after (right sample) mixing. Natural samples of tholeiitic basalt, anhydrite and calcite were crushed, manually or through the use of a Fritsch Disk Mill Pulverisette 13, and separated with a Retsch Vibratory Sieve Shaker AS 200 digit to a grain size of 300 – 350 μm at the Universität Münster; the bulk composition and purity of the natural samples was analysed with a scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). Three pure end member mixtures were prepared for each natural sample along with two 1:1 mixtures of basalt with either calcite or anhydrite, and one mixture of 2:1:1 basalt, calcite and anhydrite (Figure 1); all mixtures were prepared to weigh ~10 g and dried for ~24 hours at 110 °C to remove excess H2O. Emissivity measurements were completed at PSL under near-vacuum conditions and at temperatures ranging ~400 – 480°C; samples were heated in custom-made ceramic sample holders using an induction system and the temperature was measured at the sample surface. Hemispherical reflectance measurements in the NIR were also collected at PSL under vacuum in a modified gold-coated hemispherical unit. These reflectance measurements were completed on the mixtures prior to and following heating as they are used in the calibration of the emissivity spectra.Preliminary analysis of the measured spectra shows that the pure basalt emissivity measurements are distinguishable from mixtures of basalt with calcite, as the latter spectrum displays a downward slope; this suggests that identifying calcite on Venus using emissivity data is possible and could be used to imply if the source area has new or old lava flows. The emissivity spectra of mixtures of basalt with anhydrite, however, were less distinguishable from the pure basalt spectrum, suggesting it will be more difficult to identify the presence of anhydrite if it is not of significant quantity (i.e. more than 50% surface coverage). Mineral spectral differences can be observed using emissivity measurements under Venus conditions. Future plans involve the acquisition of measurements on a larger range of suspected gas-rock reaction minerals, proportions of reaction minerals to surface rock, and with different surface rock compositions, in order to aide analysis for when the EnVision and VERITAS orbiters arrive at Venus.

On island arcs

In world U production, the unconformity-related deposits currently yield ~24%. The main unconformity- related deposits were found in the Athabasca U-bearing province in the southwestern part of the Canadian Shield and Alligator Rivers Uranium Field of the North Australian Shield. The deposits are localized close to the surfaces of structural-stratigraphic unconformity in the bottom of sedimentary basins: Athabasca in Canada and Kombolgie in Australia. According to a series of geological–structural parameters of formation, the Canadian and Australian unconformity-related deposits significantly differ allowing their classification as subtypes. In the Canadian deposits, the ore bodies occur both above and beneath the unconformity surface of the Athabasca basin, whereas the ores of the Australian deposits are localized exclusively beneath the unconformity surface in rocks of the basement of the Kombolgie basin. This paper is devoted to the reconstruction of paleohydrodynamic formation conditions of the Australian unconformity-related deposits. The computer models of fluid migration of following three scenarios were successively considered during the analysis of fluid mass transfer processes: (i) thermal fluid convection in a fault zone with periodic upward and downward free thermal fluid convection, (ii) forced convective fluid migration at subcritical permeability and therefore the absence of free thermal convection in the fault zone, and (iii) mixed convection with upward and downward fluid movement along the fault zone. We concluded that the processes of periodic thermal convective fluid circulation in the fault zone contradict the idea of infiltration mechanism of the formation of the Australian unconformity-related deposits in fault zones in the basement of the Kombolgie basin. We, therefore, considered possible influence of facies zoning of a combined aquifer in the basement of clastic sediments of the Kombolgie Supergroup on paleohydrodynamics of the ore-bearing system, which played the role of a main migration pass for U-transporting fluids. The analysis of zonal distribution of primary sedimentation environments and later diagenetic transformations of rocks of aquifers and aquitards of this basin allowed us to substantiate an idea on leading influence of zonal decrease in permeability of rocks of the combined aquifer on a circulation structure of U-transporting fluids with the change in their lateral migration in the basement of sedimentary deposits of the Kombolgie Supergroup on the downward infiltration along a transverse zone of the ore-controlling fault. This circulation of the structure of U-transporting fluids was accepted as a hypothesis of paleohydrodynamic formation conditions of Australian unconformityrelated deposits exclusively in rocks of the basement of the Kombolgie basin. The additional computer calculations, however, showed that a trend of the directed change in the permeability of rocks along the lateral movement pass of U-transporting fluids is a trigger condition, which can be responsible both for the upward and downward fluid movement along the ore-bearing fault zone depending on the direction of the trend. In the Kombolgie basin in Australia, the direction of this trend depended on the change of facies conditions on the regional migration pass of diagenetic fluids, whereas the local topographic features of the unconformity surface could affect the Athabasca basin in Canada. At an alternative trend of variation in permeability along the lateral migration of U-transporting fluids, the proposed transport mechanism of the formation of the Australian unconformity-related deposits could probably contribute also to the formation both of infiltration and exfiltration Canadian unconformity-related deposits, which are described by a paleohydrodynamic interfault geothermal convection model.

In raising the standards for professional educators, higher educators must be prepared to provide the highest quality feedback on student performance and work products toward improved outcomes. This review of the literature examined the major findings of 70 quantitative, mixed methods, or qualitative studies found in higher education journals across a range of disciplines. Multiple recommendations and results for feedback emerged which fall into the categories described by Susan Brookhart. This review found research for each of Brookhart’s categories, with results indicating differences between the perceptions of adherence to sound feedback practices versus the reality of implementation, the potential for innovative tool use, and a disagreement about the effectiveness of peers for providing effective feedback. Indicators for quality within the research confirmed the importance of commonly accepted standards such as positivity, specificity, timeliness, and encouraging active student participation. Additionally, trends and themes indicated a need for the consistent implementation of the feedback exchange process and flexibility to account for student input/preferences. Greater consistency toward the application of these quality indicators should be undertaken when determining the quality of higher education feedback for preservice teachers prior to undertaking summative licensure assessments.

Unconventional shale oil resources have emerged as a significant source of fossil fuels in recent years. The oil contained in shales is held in natural microfractures, micropores, and inside nanopores of the organic matter. The strong capillary forces in these pores can bind the oil to the surface with strengths that are inversely proportional to the pore radius. In order to recover more oil from these pores, it is beneficial to reduce the capillary pressure by manipulating the interfacial tension and contact angle of oil/brine/shale systems using surfactant solutions. The main consideration in surfactant flooding is to optimize brine salinity and surfactant concentration while minimizing their adsorption on rock surfaces. Although the effect of some surfactants on recovery in shale oil reservoirs has been studied in the past, the mechanism is still unclear. Moreover, the limited data available in the literature is not representative of the actual reservoir conditions. The objective of this study is to elucidate the oil displacement mechanisms in shale oil by surfactant flooding. The phase behavior of several anionic surfactants was studied in the presence of crude oil at reservoir temperature (i.e. 80 °C). The results of these tests were used to screen the best surfactants. Dynamic interfacial tensions (IFT) and contact angles (CA) of selected surfactant-in-brine/oil/shale systems were measured by the rising/captive bubble technique using a state-of-the-art IFT/CA apparatus. The apparatus was thoroughly validated with various systems using the axisymmetric drop shape analysis technique. Using the same methodology, the effects of surfactant concentration (0.01 to 0.1 wt%) and brine salinity (0.1 to 5 M NaCl) on IFT and CA at ambient and reservoir conditions (i.e. 80 °C and 3000 psig) were studied. Surfactant adsorption on shale samples was also measured in brines at ambient conditions. Our data reveal that the most effective surfactant was able to reduce the oil-brine IFT from its original value (23 mN/m) down to 0.3 mN/m at reservoir condition. A reduction in the IFT value and an increase in the dynamic contact angle of oil drop on polished shale surface were observed with the addition of surfactant and salt to the system. A trend between these parameters, pressure, and temperature was also reported.

Complex feature types are defined as integrated relations between basic features for a shared meaning or concept. The shared semantic concept is difficult to define in commonly used geographic information systems (GIS) and remote sensing technologies. The role of spatial relations between complex feature parts was recognized in early GIS literature, but had limited representation in the feature or coverage data models of GIS. Spatial relations are more explicitly specified in semantic technology. In this paper, semantics for topographic feature ontology design patterns (ODP) are developed as data models for the representation of complex features. In the context of topographic processes, component assemblages are supported by resource systems and are found on local landscapes. The topographic ontology is organized across six thematic modules that can account for basic feature types, resource systems, and landscape types. Types of complex feature attributes include location, generative processes and physical description. Node/edge networks model standard spatial relations and relations specific to topographic science to represent complex features. To demonstrate these concepts, data from The National Map of the U. S. Geological Survey was converted and assembled into ODP.

Shows some basic approaches to discriminate ignimbrite type pyroclastic flow deposits in Landsat Thematic imagery of semi-arid areas. Beside certain topographical and tectonical features which already describe ignimbrites and associated pyroclastic flows in those environments, the authors' interest is focused on the influence of specific mineralogical and depositional characteristics on the spectral reflectance response. Spectral signatures in the visible and near infrared region of various fresh and weathered samples as well as desert varnish were recorded using a laboratory spectroscope to determine the factors controlling their proper response in all Thematic Mapper bands. Whole rock geochemistry data, microscopical studies and surface interpretations of the samples documented certain properties which might cause different spectral signatures also of geochemically mostly equivalent rocks.

Weathering patinas in rocks are the result of interaction processes between rock surfaces and atmosphere, biosphere and soil. Therefore, their textural and mineral composition is strongly related to environmental and bioactivity conditions. Whereas the development of weathering patinas in atmospheric conditions is well documented (e.g. typical Mediterranean patina), only very few studies focus on their formation in a burial environment. Our study of patinas developed on the tumular structure of Reguers de Seró deals with the knowledge of burial patinas from a textural and mineralogical point of view. The aims of this study include: (1) the characterisation of the rock used in this megalithic monument as well as inferences regarding the origin of the raw material; (2) the evaluation of the patinas developed on the surface of the carved steles; and (3) the discussion of the environmental conditions (atmospheric or burial) that favoured the development of the patinas. Whole rock and related patinas (powdered samples and small single pieces) were carefully sampled in five of the seven Neolithic steles discovered during a municipal excavation. Some whole rock samples from the surrounding outcrops were also collected in order to correlate them with the stone forming the megalith. Samples were analysed macroscopically, using a glass binocular, and microscopically, by means of a polarising light microscope and a scanning electron microscope (SEM-EDAX). The mineralogical composition was determined by X-ray diffraction, and a colorimetric analysis was also carried out in all the sampled patinas. The obtained results evidence a strong textural and mineralogical correlation between the whole rock of the megalith and the collected samples of the nearby outcrops; both are classified as calcarenite. A uniformly distributed beige-orange patina (35-100 microm thick) covering the surface of the steles modifies their aspect. A layer of calcite (micrite) with granular texture was detected in all the sampled patinas, being the main mineral compositions (approximately 60-90%). In contrast, a discontinuous external layer (25-50 microm thick) of botryoidally gypsum occurs on only a few patinas. SEM-EDAX analyses evidenced that Ca is related to several processes, including inorganic processes, as well as to minor bioactivity. The textural and mineralogical characteristics of the Reguers patinas differ from typical Mediterranean patina sequences, suggesting different environmental conditions for their formation. Several arguments supporting the formation of the Reguers patinas in a burial environment include: (1) patinas cover the entire surface of the steles, iconograhic motifs and fractures. The uniform colour, texture and composition of the patinas throughout the steles suggests their development after the construction of the megalithic tomb during a period in which the archaeological site was buried and sealed by the products of the Senill ravine; (2) the absence of heavy metals mainly contained in flying ashes and other depositions from atmospheric dust and pollutants in the micritic patina; (3) non-appearance of minerals directly formed by biological activity (i.e. oxalates and phosphates); (4) the absence of a well-defined textural sequence (typically of the Mediterranean area) already defined for patinas developed in an atmospheric environment; and (5) the discontinuous occurrence of an external gypsum layer (only present in a few samples) without the presence of the typical spherules related to atmospheric particulate matter. The petrographic characteristics of the Neolithic steles of Reguers de Seró show that the raw material came from a nearby outcrop. The formation of beige-orange patinas is related to a burial environment attending their textural and mineralogical features. The protective role played by these patinas indicates that no previous treatment of such steles would be necessary on an eventual exhibition in atmospheric conditions. Further in-depth studies, similar to those that already exist for patinas developed in atmospheric conditions, are recommended in order to better define the petrographic characteristics and mechanisms on the formation of patinas in burial environments.

Accurate and reliable assessment of site suitability for the growth of selected plant species is critical for afforestation projects and programs to improve rural livelihoods. This research examines the relationship between growth of Sterculia foetida L. and six ecological factors in Buon Don and Ea Sup districts, Dak Lak Province. The purpose of the research is to predict the growth in average height and trunk diameter of the trees using ecological factors that are easy to measure and observe. These include topography (slope) and soil characteristics (clay ratio, depth of soil layer, surface and subsurface rock concentrations, and agglomeration ratio). The ecological factors were evaluated by multivariable regression analysis of growth data from 31 experimental plots, 16 in Buon Don district and 15 in Ea Sup district. The results show that four of the six factors affect average growth in tree height and that five factors affect average trunk diameter growth. The findings are of practical value for households and agricultural extension officers to consider before planting Sterculia foetida L. in the two areas.

Generally, pressure and fluid communications between parent and child wells which is referred to as frac hit deteriorate the production performance of the parent well. Small pre-loading technique is one of the cost-efficient and operationally simple strategies to mitigate frac hit. However, the production outcome of the parent well is unsatisfactory after flowback of pre-loading fluid in most of the pilots. To overcome this negative impact, we intend to evaluate the extent of additional oil recovery by imbibition of fluids with two types of non-ionic surfactant additives (SF-1 and SF-2) during pre-loading and flowback processes. We utilize a high-pressure and high-temperature visualization cell to conduct the pre-loading experiments using Montney rock and fluid samples. We restore the initial reservoir condition in the core plug and then simulate the primary production stage of the reservoir to establish a depleted core plug. Then, we conduct two sets of experiments on the depleted core plug: 1) soaking the plug with SF-1 surfactant solution under atmospheric conditions and 2) pre-loading the depleted core plug with the SF-1 surfactant solution at a pressure of 3,500 psig and reservoir temperature of 78°C. We also pre-load an oil-saturated core plug with SF-2 surfactant solution at similar operational conditions. Our results show that 31.4% of the original oil-in-place is produced during the primary production stage with solution-gas drive as the dominant oil-recovery mechanism. We observe an additional 3.9% (of original oil-in-place) oil recovery due to counter-current imbibition of the SF-1 surfactant solution after soaking under atmospheric conditions. The interfacial tension reduction and wettability alteration are two possible oil-recovery mechanisms during surfactant soaking. Pre-loading the depleted core plug with SF-1 surfactant solution at a set pressure of 3,370 psig and a temperature of 78°C does not result in additional oil recovery. However, pre-loading the oil-saturated core plug with SF-2 surfactant solution at the same operational conditions results in an approximately 29.6% oil recovery. We observe oil droplets formed on the rock surface during soaking of the oil-saturated plug with SF-2 surfactant solution. We conclude that longer soaking periods may assist in additional oil recovery in core plugs with depleted state compared to the non-depleted plugs.

Kaolinite flakes and coal fines production in lignite core under ambient conditions: A case study of Neyveli Lignite Field at Cauvery Basin, Southern India

ABSTRACTA procedure for the measurements of the redox capacity of rocks and minerals is presented. Both solid and pulverized samples are used. In a preliminary test described in this paper, an oxygen loss of an aqueous solution in contact with pulverized granodiorite was measured directly on-line, with an oxygen sensor.The increase of Fetot in the solution responded relatively well to the oxygen consumption. The maximum rate varied from 3.0 × 10−4 to 9.0 × 10−11 mol l−1 s−1 correspondingly. Oxygen loss of 0.04 mmol (O2) and iron increase of 0.1 mmol were recorded in the solution. Fe(II) reduction in the solid phase was also examined. Fe(II) was inferred to have partially dissolved during the experiment. When the system was equilibrated at the ambient conditions, the vessel was pressurized upto 100 bar with oxygen gas. Three weeks later, the additional decrease of Fe(II) in the solid phase was minimal, only 0.07 % Fe(II) was dissolved or oxidized on the rock surfaces. At this point, the Fetot in the solution, had decreased down to the background level. According to the total oxygen loss at the ambient coditions, the maximum redox capacity of the examined granodiorite (BET 1.0 m2/g) is 0.002 mmol/m2.