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A 2D walkway vertical seismic profile (VSP) survey was conducted using a distributed acoustic sensing (DAS) system in southwest Utah, which is part of an enhanced geothermal system (EGS) project. The VSP was undertaken to obtain detailed structural information for a better understanding of the area's subsurface geology and associated fracture development. By combining a 3D composite velocity model from previous studies and considering the complex geological structure beneath this region, we processed the data to create P-P depth image. We also modified the interval Q calculation using a moving window over the gauge-length corrected DAS record to generate the velocity profile and the comparable interval attenuation curve. The correlated P-P images from two DAS records successfully indicate not only the main contact between shallow unconsolidated sediments and the metamorphic basement rocks at 2650 ft (807.72 m) but also several distinct reflections related to the geological contacts. The refined velocity profiles and the depth images can provide baseline results for further seismic modeling and time-lapse imaging. [ABSTRACT FROM AUTHOR]

Identifying distributed strain sensing (DSS) patterns (or signatures), particularly those arising from different hydraulic fracture geometries, has gained significant attention and research effort. Recent works have generated a catalogue of signatures for planar hydraulic fractures in an elastic rock formation. Yet, in numerous cases (e.g., fault motion and some geothermal reservoir stimulation), the main mode of deformation is a shear on a fracture or a network of natural fractures (particularly during low pressure injection/circulation). However, the specific fiber signatures that result from such shear deformation have not been studied. In this study, we use a three-dimensional poroelastic hydraulic fracture simulator to capture the strain signatures resulting from the shear deformation of fractures in various orientations with respect to the monitoring well. Five key cases are examined: one where the fracture strike is perpendicular to the fiber, another with the strike running parallel to the fiber, a third case where the fracture strike is at 45 degrees to the fiber, a fourth case with a strike slip fault perpendicular to the fiber, and a fifth case where fiber is intersecting the fracture. Theoretically and physically meaningful results were obtained in all five cases, which completely differ from the heart-shaped signature of tensile fracture propagation. It was discovered that the strain pattern changes with the shear deformation direction with respect to the fiber. The model is then used to simulate the response of a fracture network at Utah FORGE to injection to assess whether a signature might be expected in response to the planned injection and circulation rates, and, if so, what strain pattern might be expected. The simulation confirms that a strain response can indeed be observed. More importantly, the fiber response that would be detected in the monitoring well would be a combination of strain signatures from dilation and shear deformation of differently oriented natural fractures. The results in this study provide useful insights on the application of fiber to other stimulation and/or circulation scenarios where shear deformation of a fracture or fracture network plays a major role. [ABSTRACT FROM AUTHOR]

Superlight Mg-10Li-3Al-3Zn (LA103Z) alloy cabins were fabricated by the integration of multi-directionally forging (MDF), die forging, and annealing treatment. α-Mg, β-Li, AlLi, MgLi2Al, and Mg17Al12 phases are detected in the as-cast alloy. Dynamic precipitation dominates during MDF and the relatively randomized macro-texture endows the MDFed billet with quasi-isotropic tensile properties. During subsequent compression, the grain growth and phase dissolution tend to occur with the decline of Zener–Hollomon parameter. The cabin die-forged at 260 °C and 6 mm/s owns the superior strength compared with the other cabins, which should be attributed to the sufficient dissolution of AlLi phases, fine grain size, reasonable amount and distribution of MgLi2Al particles, etc. Further annealed at 245 °C for 3 h, the above cabin exhibits the optimal comprehensive mechanical properties with the tensile yield strength (TYS) of 211 MPa, ultimate tensile strength (UTS) of 243 MPa, and elongation of 20.0%. This work provides a feasible way for industrial production of high-performance large-scale Mg-Li components. [ABSTRACT FROM AUTHOR]

A 2D walkway vertical seismic profile (VSP) survey was conducted using a distributed acoustic sensing (DAS) system in southwest Utah, which is part of an enhanced geothermal system (EGS) project. The VSP was undertaken to obtain detailed structural information for a better understanding of the area’s subsurface geology and associated fracture development. By combining a 3D composite velocity model from previous studies and considering the complex geological structure beneath this region, we processed the data to create P-P depth image. We also modified the interval Q calculation using a moving window over the gauge-length corrected DAS record to generate the velocity profile and the comparable interval attenuation curve. The correlated P-P images from two DAS records successfully indicate not only the main contact between shallow unconsolidated sediments and the metamorphic basement rocks at 2650 ft (807.72 m) but also several distinct reflections related to the geological contacts. The refined velocity profiles and the depth images can provide baseline results for further seismic modeling and time-lapse imaging.

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents the results of testing the conditions of closing foundry voids during the hot forging operation of an ingot made of zirconium with 1% Nb alloy and use of physical and numerical modeling, continuing research presented in a previous thematically related article published in the journal Materials. The study of the impact of forging operation parameters on the rheology of zirconium with 1% Nb alloy was carried out on a Gleeble 3800 device. Using the commercial FORGE®NxT 2.1 program, a numerical analysis was performed of the influence of thermo-mechanical parameters of the hot elongation operation in trapezoidal flat and rhombic trapezoidal anvils on the closure of foundry voids. The analysis of the obtained test results was used to formulate recommendations on the technology of hot forging and the anvilgeometry, ensuring closure of foundry voids. Based on their research, the authors conclude that the shape of the deformation basin and the value and hydrostatic pressure have the greatest influences on the closure of foundry voids. [ABSTRACT FROM AUTHOR]

Identifying distributed strain sensing (DSS) patterns (or signatures), particularly those arising from different hydraulic fracture geometries, has gained significant attention and research effort. Recent works have generated a catalogue of signatures for planar hydraulic fractures in an elastic rock formation. Yet, in numerous cases (e.g., fault motion and some geothermal reservoir stimulation), the main mode of deformation is a shear on a fracture or a network of natural fractures (particularly during low pressure injection/circulation). However, the specific fiber signatures that result from such shear deformation have not been studied. In this study, we use a three-dimensional poroelastic hydraulic fracture simulator to capture the strain signatures resulting from the shear deformation of fractures in various orientations with respect to the monitoring well. Five key cases are examined: one where the fracture strike is perpendicular to the fiber, another with the strike running parallel to the fiber, a third case where the fracture strike is at 45 degrees to the fiber, a fourth case with a strike slip fault perpendicular to the fiber, and a fifth case where fiber is intersecting the fracture. Theoretically and physically meaningful results were obtained in all five cases, which completely differ from the heart-shaped signature of tensile fracture propagation. It was discovered that the strain pattern changes with the shear deformation direction with respect to the fiber. The model is then used to simulate the response of a fracture network at Utah FORGE to injection to assess whether a signature might be expected in response to the planned injection and circulation rates, and, if so, what strain pattern might be expected. The simulation confirms that a strain response can indeed be observed. More importantly, the fiber response that would be detected in the monitoring well would be a combination of strain signatures from dilation and shear deformation of differently oriented natural fractures. The results in this study provide useful insights on the application of fiber to other stimulation and/or circulation scenarios where shear deformation of a fracture or fracture network plays a major role.

For effective fracture stimulation in Enhanced Geothermal Systems (EGS), characterization of subsurface rock elastic properties is essential. Because seismic anisotropy significantly influences hydraulic fracturing, locating and characterizing microseismic events, and forecasting stress trajectories, our research undertakes laboratory experiments to study seismic anisotropy parameters of core samples from the Utah FORGE EGS site. We evaluated two rock samples from well 58–32, at two depths of 2074.16 m (6,805 feet) and 2268.01 m (7,441 feet), respectively. We analyze the mineralogy and classify the shallower rock as syenogranite, and the deeper rock as orthogneiss and monzonite. We cut cylindrical plugs from these two core samples, imaged them by computed tomography (CT) X-ray imaging, and measured their seismic anisotropy using ultrasonic waves at 1 MHz and under varying confining pressures (5–50 MPa) in ambient temperature conditions. With the assumption of the transversely isotropic (TI) medium, we measured three P-wave velocities and two S-wave velocities along different propagation directions to compute the Thomsen anisotropy parameters. Our results showed that the measured seismic velocities of each rock sample increase with increasing effective pressures, a behavior likely caused by closure of microcracks identified in our CT images. We also find that the measured anisotropies are higher at lower effective pressures. The maximum measured anisotropies for P-waves and S-waves are ∼23% and ∼20%, respectively. Therefore, we expect in the field operation that anisotropy should increase with increasing pore pressure caused by injection, which could be valuable in future EGS reservoir management and monitoring. [ABSTRACT FROM AUTHOR]

The article analyzes information about noble households located in the provincial city of Pskov, which were sold at the beginning of the XIX century by order of public charity. The history, structure and composition of households, location in urban development and the cost at which they were purchased for public needs are considered. The comparable data are recorded in the purchase cases and allow us to describe the real estate belonging to noble families in the city limits and its condition at the time of sale. Attracted sources of the beginning of the XIX century. They characterize the possessions of noble families of the Pskov province and urban development on the territory of Pskov, which develops in the second half of the XVIII century, and also allow us to determine the reasons for the sale of property. On individual examples of real estate inventories, the specifics of the organization of economic life among noble families in the provincial city are traced. The sources involved allow us to trace the processes of restructuring and dilapidation of households, their expansion and renewal in the realities corresponding to the time. The organization of the economic life of the noble household in the city is characterized by thoroughness and functionality, as evidenced by the presence of stables, sheds, barns and other outbuildings. The mention of gardens as part of the noble possessions in the city limits testifies to the significant areas that the nobles owned.

This paper mainly studies the influence of process parameters on the forming quality during the spinning process of 6061 aluminum alloy wheel forging blanks. The four parameters of spinning temperature, spindle speed, wheel feed and wall thickness reduction rate are selected for research, and the quality of the surface of the hub and the influence on the size of the hub are judged. Simufact software is used to simulate the influence of various process parameters on the forming quality of the hub. The results provide a certain reference for the reasonable selection of process parameters during the spinning forming process of 6061 aluminum alloy hub.

Friction welding is a solid-state welding system which welds materials without authentic melting it. This study explores papers of different researchers on the friction welding method and it has been observed that the welding parameters like friction time; friction pressure, forge time and forge pressure highly affect properties of welded joints. The reason for this investigation is to exhort industry and the insightful world regarding advantages of revolving friction welding so the technique may be utilized in an ideal manner.

Aluminum alloys are widely used for structural parts in the aerospace industry. Those parts are usually machined from rolled plates or forged blanks, and heat treatments are carried out to reach the necessary mechanical properties. Forming and heat treatments induce residual stresses that generate deformations during and after machining because material removal modifies their balance. One major issue in industry is the important variability of the residual stress field in forged blanks. A better knowledge of the residual stress field will enable the definition of better machining strategy to minimize the deformations. In order to understand and manage this variability, a sensibility analysis was performed to investigate the impact of their different potential sources. It relies on a coupling of 2D-FEM and beam model simulations. Then, this work introduces a model reduction technique (by POD and SVD) to build a model of the variability of a stress field and shows how it could be used on the production line. [ABSTRACT FROM AUTHOR]

This paper mainly studies the influence of process parameters on the forming quality during the spinning process of 6061 aluminum alloy wheel forging blanks. The four parameters of spinning temperature, spindle speed, wheel feed and wall thickness reduction rate are selected for research, and the quality of the surface of the hub and the influence on the size of the hub are judged. Simufact software is used to simulate the influence of various process parameters on the forming quality of the hub. The results provide a certain reference for the reasonable selection of process parameters during the spinning forming process of 6061 aluminum alloy hub. [ABSTRACT FROM AUTHOR]

In order to study the influence of process parameters on the forming force during the forging and spinning process of the wheel hub, five parameters were selected: die preheating temperature, blank temperature, upper die down speed, friction coefficient and feed rate.Use Deform and Simufact software to simulate and obtain the influence law of each process parameter on forming force. The results provide a certain reference for reasonable selection of process parameters in the forming process.

A lot has been said and written about workplace informal groups. By and large the presence of workplace informal groups has been welcomed by several stakeholder categories, subject of course to a few caveats. The commonest caveat is that the goals the informal groups chase should be in line with the goals the organisation concerned chases. Prima facie, such a caveat is welcome but often this caveat is projected as the pivot on which alone the success of the informal group rests. Other aspects are often side-lined or ignored with the result that the informal group's performance at times gets suboptimal and less inclusive. A little bit of fine-tuning, like ensuring that the informal group gets more inclusive, can go a long way in raising workplace productivity. The researcher's findings reveal that persuading more and more women employees to associate with committed workplace informal groups can go a long way in ensuring that the entire workforce jells at the workplace, leading to superior productivity for the organisation. Although a few valid reasons come in the way of the women employees associating themselves actively with the workplace informal groups, if the right inducement is made available at the right time to the women employees, a more inclusive workplace informal group will emerge. Ensuring a better shop floor presence for women employees, allaying their fears and suspicions and ensuring a fair workplace treatment for them are among the measures the researcher suggests, to forge a more inclusive and committed workplace informal group. [ABSTRACT FROM AUTHOR]

An increase in hydrostatic stress improves the plasticity of metallic materials. However, for some special components, such as large thin-walled components with high ribs, excessive hydrostatic stress can cause several problems that make it impossible to prepare such components using plastic forming methods. In this study, the effect of hydrostatic stress on the deformation behavior of large thin-walled components with high ribs was investigated using a combination of numerical simulations and theoretical derivations. The results indicated that excessive hydrostatic stress leads to die failure, causing metal flow difficulties, uneven deformation, inconsistent mechanical properties, and reduced forming accuracy. Therefore, a low-hydrostatic-stress extrusion method was proposed by adjusting the contact friction, metal flow direction and displacement, and force boundary conditions to reduce the hydrostatic compressive stress. These principles are mainly reflected in the following three aspects: First, the size of the difficult deformation zone was reduced by changing the friction conditions from dry friction to fluid friction or boundary friction to reduce the frictional resistance. Second, the high-stress zone was eliminated by changing the metal flow direction, adjusting the strain state from unidirectional to multi-directional flow, shortening the metal flow path, and reducing the metal flow resistance. Third, the strong compressive stress state in the three directions was weakened by regulating the force boundary conditions and changing the loading method from one-way extrusion to multi-directional loading. Based on these principles, a series of new forming technologies have been developed, such as actively counteracting frictional resistance, slotting, and ditching on dies for long-lasting lubrication, multi-directional short-range metal flow, drawing-assisted extrusion, and multi-directional active loading. The adoption of these technologies realizes the labor-efficient formation of large thin-walled components with high ribs and provides the formed members with high precision and uniform mechanical properties. [Display omitted] • The influences of hydrostatic stress on metal flow, forming forces and strains were revealed. • The principle of low hydrostatic stress extrusion was developed, which can be employed to reduce the working stress. • The forming force was reduced, and the deformation uniformity and forming accuracy of thin-walled components were improved. [ABSTRACT FROM AUTHOR]

Copyright of Revue Archéologique de Picardie is the property of Revue Archeologique de Picardie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the Middle Ages arms and armour were considered luxury products. They were not used every day and not by everyone. Nonetheless, the circle of their buyers was relatively wide, making their prices extremely diversified. On the other hand, as weaponry was bought every several years, the demand was limited. It resulted in a relatively small number of workshops in which weapons were produced. Besides specialised production sites located in towns or at royal courts, there were also rural forges, where arms and armour were produced for the needs of less wealthy members of the medieval society. The production of armaments in the borderlands of Silesia, Greater Poland, Brandenburg and Lusatia (roughly equivalent to today’s Lubuskie Voivodeship), laying mostly outside the borders of medieval Poland, has not been yet explored in the scholarly works. Researching the subject is difficult due to the lack of direct sources. There is, however, some indirect evidence. Iron, in medieval times obtained mainly from bog ores, was the most important raw material for the manufacture of a majority of military equipment. Therefore, the first indication of the arms and armour manufacturing in the studied borderland during the Middle Ages and the Early Modern Period can be found in written sources, which mention many small metallurgical workshops (forges and hammer-mills). Early mentions concern following settlements: Drożków near Żary, Klikowa near Iłowa, Szprotawa (Sprottau), Łozy upon the Kwisa, Sanice near Przewóz, Dobrzyń and Bucz (Fig. 1). Direct evidence confirming the functioning of s place of iron production was discovered during archaeological excavations in Podrosche (former part of Przewóz). Most scholars assumes that rural smithies did not participate in the production of arms and armour on a large scale, mostly limiting their activity to horseshoeing, forging basic agricultural and carpentry tools (including axes and hatchets) as well as sharpening and repairing more elaborate artefacts . Mass-produced arrow- and boltheads, as well as iron parts of staff weapons, could also be manufactured there, although rather only in times of war. Remains of such a rural smithy (dated to the 15th c.) were recorded in Nowa Wieś, Międzyrzecz District (Fig. 2). A large amount of iron slag was found in the fill of the feature, along with smithing tools, finished and unfinished smithing products and also pieces of armaments. Castle forges were more specialised in manufacture and repair of individual parts of military equipment. Remains of such workshops were found, among others, in: Miedzyrzecz (Fig. 3) and Santok (Fig. 4), while inventories of the Teutonic castles in Kostrzyn (Küstrin) and Drezdenko, in which large amounts of saltpetre, sulphur and lead was recorded, may indicate that gunpowder and projectiles were produced in those strongholds. Little is known about metal crafts’ organisation in the region as written sources provide almost no information. (Fig. 5) There is no doubt that blacksmith guilds existed in larger towns of the area, as it was typical for medieval urban centres of Central and Western Europe, although the relatively late mentions in written records provide little information on the subject. Some data was acquired as a result of examination of archaeological finds. Some of them are signed with craftsmen’s marks, which if identified may indicate a place of origin for particular pieces of arms. They, however, show these objects were manufactured outside the region (Fig. 6). It is finds like unfinished items and intermediate products that can suggests local production of armaments in the places where they were discovered (Fig. 7). Therefore, indirect evidence shows that although the scale of the production was rather small, it met the demand of local purchasers (of various wealth). The need for simple and mass produced arms might be fulfilled by castle, town and rural forges.

In this paper a new scheduling problem is presented, which originates from the steel processing industry. The optimal scheduling of a steel forge is investigated with the goal of minimizing setup and storage costs under strict deadlines and special resource constraints. The main distinctive feature of the problem is the deterioration of some equipment, in this case, the so-called forging dies. While the aging effect has been widely investigated in scheduling approaches, where production speed decreases through time, durability deterioration caused by equipment setup has not been addressed yet. In this paper a mixed-integer linear programming model is proposed for solving the problem. The model uses a uniform discrete time representation and resource-balance constraints based on the resource–task network model formulation method. The proposed method was tested on 3-week long schedules based on real industrial scenarios. Computational results show that the approach is able to provide optimal short-term schedules in reasonable time. [ABSTRACT FROM AUTHOR]

More than 50% of atypical meningiomas regrow within 5 years after surgery. FORGE score is a newly created tool to estimate the MIB-1 index in cranial meningiomas. In this investigation, we aimed to assess the predictive value of the FORGE score in combination with major diagnostic criteria of atypical meningioma (brain invasion, mitotic count ≥ 4) regarding recurrence in atypical meningiomas. We included patients operated on primary atypical meningiomas in our center from 2011 to 2019. The study included 71 patients (58% women, median age 63 years). ROC curves revealed a superiority of FORGE score combined with histopathological diagnostic criteria of atypical meningioma (AT-FORGE) in the prediction of tumor progression compared to FORGE score only (AUC: 0.72; 95% CI: 0.54–0.91, cut-off: ≥5/p < 0.001) in the univariable analysis. Multivariable cox regression analysis revealed significant predictive value of Simpson grade > II, presence of multiple meningiomas and AT-FORGE score ≥ 5 for tumor progression. The combination of histopathological diagnostic criteria for atypical meningioma with FORGE score might facilitate an effective identification of patients with an atypical meningioma who have an increased risk of tumor progression.

The Frontier Observatory for Research in Geothermal Energy (FORGE) site is a multi-year initiative funded by the U.S. Department of Energy for enhanced geothermal system research and development. The site is located on the margin of the Great Basin near the town of Milford, Utah. Work has so far resulted in the compilation of a large amount of subsurface data which have been used to improve the geologic understanding of the site. Based on the compiled data, a three-dimensional geologic model describing the structure, composition, permeability, and temperature at the Utah FORGE site was developed. A deep exploratory well (Well 58-32) and numerous tests conducted therein provide information on reservoir rock type, temperature, stress, permeability, etc. Modeling and simulation will play a critical role at the site and need to be considered as a general scientific discovery tool to elucidate the behavior of enhanced geothermal systems and as a deterministic (or stochastic) tool to plan and predict specific activities. This paper will present the development of a reference native state model and the calibration of the model to the reservoir pressure, temperature, and stress measured in Well 58-32.

The response of the Fallon FORGE geothermal reservoir to hydraulic stimulation is modeled numerically to aid the conceptual design of the well geometries and completions. The numerical modeling approach is based on (a) a full hydro-mechanical coupling; and (b) explicit representation of a discrete fracture network (DFN). The reservoir-scale model has a core region of 1500 × 1200 × 1200 m3 volume around the positions of conceptual sub-horizontal well designs at the Fallon FORGE site. It contains relevant geological structure and a fracture network constructed and simplified using borehole data. Stimulation was modeled in six stages/zones along the horizontal well using both openhole (low injection rate at 5 kg/s) and cased borehole (combination of high, 80 kg/s, and low injection rates) completions to test the effectiveness of hydraulic fracturing combined with hydro-shearing. The reservoir stimulation in the two models was analyzed and quantitatively assessed. Results indicate that the Fallon FORGE site is well suited for an EGS by multi-staged hydraulic stimulation using sub-horizontal wells. The conclusion is based on the evaluation of potential for fracture slip and aperture increase as functions of induced pressure changes and the orientations of the natural joints relative to the regional principal stresses. Advantages and limitations of explicit representation of the DFN in the numerical models are presented and discussed. [ABSTRACT FROM AUTHOR]

This work was carried out in the region of the Mundaú river estuary in the municipality of Trairi-CE, from February to June 2018, and aimed to characterize the Ucides cordatus crab fishery in the region. The fishing of crab-uçá is carried out mainly with the fishing apparatus known as forge. This fishing apparatus is considered passive and is made from polyethylene terephthalate (PET) bottles, elastic rubber bands, wire, small parts of polyvinyl chloride (PVC) and mangrove wood. Each fisherman uses from 50 to 60 forges, distributed by several points in the mangrove. In this study, the mean weight (g) and carapace width (Lc, mm) of 164.9g and 69.1mm, respectively, were obtained for males, and 113.5g and 63.7mm for females from a total of 189 individuals. Considering the conditions under which this crab is being fished in the community, this activity represents one of the few income alternatives in the region. [ABSTRACT FROM AUTHOR]

Abstract A high-strength AZ80 alloy (with a tensile strength of 285 MPa, an ultimate strength of 388 MPa, and an elongation of 6.8%) has been fabricated by multidirectional forging (MDF) under air-cooling condition, at an initial temperature of 360 °C, with an accumulative strain of 1.8, with no need of ageing treatment. Extensive dynamic precipitation occurs in this sample, which deteriorates the subsequent age-hardening response but still contributes to improving the strength. In addition to the precipitation hardening caused by numerous nano-scale dynamic precipitates, the outstanding strength should also be attributed to the combined effects of other microstructural characteristics resulting from the increase of accumulative strain and decrease of forging temperature. They are 1) grain boundary strengthening by fine recrystallized grains, 2) strain hardening by the large dislocation density, and 3) texture strengthening by the low Schmid factor of basal slip. This paper provides a method of short process to manufacture high-performance large-scale AZ80 components for industrial production. Graphical abstract Image 1 Highlights • A high-strength AZ80 alloy is fabricated by multidirectional forging in air. • Dynamic precipitation extensively occurs as the accumulative strain increases. • Dynamic precipitates have advantage in maintaining the ductility compared with ageing precipitates. • Forging along two orthogonal directions shares a similar texture characteristic to extrusion. [ABSTRACT FROM AUTHOR]

In order to study the influence of process parameters on the forming force during the forging and spinning process of the wheel hub, five parameters were selected: die preheating temperature, blank temperature, upper die down speed, friction coefficient and feed rate.Use Deform and Simufact software to simulate and obtain the influence law of each process parameter on forming force.The results provide a certain reference for reasonable selection of process parameters in the forming process. [ABSTRACT FROM AUTHOR]

A scientific injection campaign was conducted at the Utah Frontier Observatory for Research in Geothermal Energy (FORGE) site in 2017 and 2019. The testing included pump-in/shut-in, pump-in/flowback, and step rate tests. Various methods have been employed to interpret the in-situ stress from the test dataset. This study focuses on methods to interpret the minimum in-situ stress from step rate, pump-in/extended shut-in tests data obtained during the stimulation of two zones in Well 58-32. This well was drilled in low-permeability granitoid. A temperature of 199 °C was recorded at the well’s total depth of 2297 m relative to the rotary Kelly bushing (RKB). The lower zone (Zone 1) consisted of 46 m of the openhole at the toe of the well. Fractures in the upper zone (Zone 2) were stimulated between 2123–2126 m measured depths (MD) behind the casing. The closure stress gradient variation depended on the depth and the injection chronology. The closure stress was found to increase with the pumping rate/volume. This stress variation could indicate that poroelastic effects (“back stress”) and the presence of adjacent natural fractures may play an important role in the interpretation of fracture closure stress. Further, progressively increasing local total stresses may, consequently, have practical applications when moderate volumes of fluid are injected in a naturally fractured or high-temperature reservoir. The alternative techniques that use pump-in/flowback tests and temperature signatures provide a valuable perspective view of the in-situ stress measurements.