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Michigan State Department of Conservation, Lansing, Mich The Department of Conservation has two divisions issuing publications which should be listed in this directory. Geological Survey Division. R. A Smith, State Geologist Land Economic Survey Division L R Schoenmann, Head. A price list of publications of either division will be sent upon request to that division Geological Survey Division.-Citizens of Michigan may obtain publications of this Division on payment of forwarding charges Prices to others for available publications are given below: Vol 5 (1881-1884): Pt 1, Geological report of the Upper Peninsula of Michigan, by L L Hubbard, pt 2, Geology of Lower Michigan with reference to deep borings, by A C Lane, $125. Annual Report for 1908. Pt b, Geological section of Michigan, by A C. Lane and A E Seaman, 50 cents. Publication No 5, The Late Glacial and Post Glacial Uplift of the Michigan Basin, and earthquakes in Michigan, by W. H

Jan 1, 1933

By Rafael Errazuriz

About eighty miles north of the city of Antofagasta, Chile, located just below the Tropic of Capricorn, there spreads a wide desert area where copper oxide outcrops can be seen with the naked eye. Numerous old mining works and dump heaps with the green of atacamite and chrisocolla shining in the blazing sun, attest to the work done by miners in the beginning of this century. The dry desert air preserves the footstep marks, paths and trails of old cartwheels from years back. The mining area known as Michilla and Panizos Blancos, is located on the high plateau at 3000 ft above sea level. Around 1920 a Bleichert ropeway was built, which carried ores from the best known mine to a wharf at the Michilla bay. High grade silicious ores were shipped to the Gatico Smelter further north or to smelters in the United States or Japan.

Jan 8, 1973

By Klinefelter G

The United States Steel Mining Co., Inc. recently experienced a major mine fire at the Cumberland Mine. This mine is located in Greene County, Pennsylvania, U.S.A. and is mining a high volatile bituminous coal seam (Pittsburgh Seam). The mine fire was success- fully controlled and extinguished without loss of life or serious injury to any miner or mine rescue personnel and finally reopened within 40 days of its inception.

Jan 1, 1988

By David P. Reddick

Economics is a social science dealing with the allocation of scarce resources. In modern times the “science” was identified by Adam Smith in his book, The Wealth of Nations, written in 1776. Mr.Smith, highly influenced by the Mercantilists of the 17th and 18th centuries, identified the “Invisible Hand” which would lead every individual to pursue selfish rewards in purchasing goods. He speculated these selfish motives would result in the best good for all. Price would be determined by barter, at a point where self-centered customers and vendors were mutually satisfied. Today, Smith’s theory is known throughout the world as “Capitalism” but most often termed “Free Enterprise” in the United States.

Jan 1, 1992

By Wesley, Worner H

During the meeting of the Institute last year at Port Pirie, the opportunity was taken to sample the lead bullion coming from the blast furnace and various stages during the refining process. Also, in the desilverising section, the upper zinc rich phase was sampled as the silver content built up and in the cupellation operation a series of samples was taken as the silver content of the bullion increased. In these two cases, the samples were taken under the supervision of a member of the staff of the Broken Hill AssociatedSmelters.In the following account of the microstructure of the samples taken, only the main phases present have received attention. In this connection deduction from phase diagrams of binary alloys has been used in conjunction with the assays carried out on duplicate samples taken at the same time as those for micro examination.

Jan 1, 1938

By G. A. Rosario, G. Peach

Twin 8.5 m diameter, 10 km long headrace tunnels under overburdens of up to 1870 m were excavated for the neelum jhelum hydroelectric project in north-eastern pakistan using two main beam gripper tunnel boring machines (tbms). Rock bursts were encountered and presented a significant danger to personnel and equipment. Micro seismic monitoring was installed to analyze rock burst characteristics and to create a database for future reference. Correlation of rock burst characteristics improved the ability to predict the likelihood, location, severity, and number of rock burst events. This paper presents the analysis of the micro seismic data

Dec 1, 2022

By Zhenqi Cai

The ongoing Overpeck Valley Parallel Sewer Project of Bergen County Utilities Authority (BCUA), New Jersey, is a US $65 million CSO improvement program to meet a State DEP consent order by 2010. One major program component includes a total of 1.8 km (1.2 mile) long, 1,800 mm (72 in) diameter reinforced concrete pipe (RCP) installed by a Herrenknecht AVND1800AB MTBM. The alignment includes drives through 850 m (2,788 ft) of extremely soft glaciolacustrine varved clay, 980 m (3,214 ft) of loose to medium dense mixed soils containing silty sands, gravels, and boulders, and crosses under the New Jersey Turnpike, US Highway Route 46, and a CSX Railroad Intermodal Yard and a branch mainline. Two types of MTBM cutterheads are being used, one configured for the weak varved clay, and one for the mixed soil conditions. The MTBM is also equipped with a double-steering system consisting of a standard front steering joint and a second trailing steering joint to assist grade control should adequate steering not be achieved by the front primary steering in extremely weak soil conditions. This paper discusses the significant engineering aspects and challenges related to site settings, ground characterization, key MTBM features and performance, and required ground treatment.

By Xinli Wang, Matthew Andriese, Jiann-Yang Hwang, Zhiwei Peng, Byoung-Gon Kim

"The microwave reflection loss (RL) of ferric oxide is studied in the temperature range from 297 to approximately 1400 Kat frequencies of 915 and 2450 MHz. It is shown that the maximum microwave absorption with RL of -38.46 and -35.97 dB can be obtained for ferric oxide having thicknesses of 0.03 and 0.01 m at 915 and 2450 MHz, respectively. The maximum absorption peak with RL below -10 dB is in a 250 K temperature range from 723 to 973 Kat 915 MHz, which shifts to the range between 823 and 1073 K at 2450 MHz. This migration is in good agreement with the variation of the dielectric loss tangent of ferric oxide.IntroductionMicrowave irradiation has distinguishing characteristics such as volumetric and selective heating compared with conventional methods, leading to extremely broad applications in materials heating and processing [1-5].The efficiency of microwave heating was found to be dependent on various factors, such as microwave power [6], frequency [7,8], radiation time [8], applicator geometry [8], sample microwave absorption properties and position as well as dimension [9-11 ], etc. Among these parameters, sample dimension plays an important role but is usually neglected by researchers in microwave processing of materials. In fact, although numerous studies have been directed toward the utilization of microwave energy to assist materials heating and processing, few reports were released on the effect of sample dimension [12,13].This is because all aforementioned factors influencing microwave heating generally exert interactive effects to each other during the heating process, making clarification of the effect of sample dimension difficult. Therefore, it is necessary to propose a parameter or concept for quantifying the effect of absorber dimension on microwave heating, increasing heating efficiency."

Jan 1, 2013

By Robert R. Beebe

At first glance, mineral processing on an industrial scale might seem entirely in the realm of macro-engineering, with large machines operating on minerals and rocks to achieve size reduction, classification, chemical treatment, separation and dewatering. These operations must be conducted on a large scale to be of practical interest. But the machines and processes may not be designed and operated to take fullest advantage of micro-engineering factors. At the same time, idealized designs based solely on micro-engineering research may require adjustments to gain the desired results in the larger scale, operational context. Using micro-engineering research in this way allows the design and implementation of more efficient versions of the machines and processes currently used, while aiding the revolutionary developments unlikely to come from macro-engineered, trial-and-error solutions. Thus, from an industrial viewpoint, micro- and macro-engineering are complementary functions.

Jan 1, 1992

By Nomuqhele N. Nkosi, Yasuo Yabe, Musa D. Manzi, Raymond J. Durrheim, Siyanda B. Mngadi

This study examined rock failure in brittle rocks hosting the deep gold-bearing ore bodies on scales between millimeters and kilometres. This research study is part of the International Continental scientific Drilling Program (ICDP) project, “Drilling into Seismogenic Zones of M2.0-M5.5 earthquakes in deep South African gold mines” (DSeis). The broader ICDP-DSeis project aims include the examination of the extent of damage, the stress state around the fringes of the earthquake, and the potential existence of living organisms associated with deep-level earthquakes. Nevertheless, this study focused on two seismogenic zones – the Cooke 4 mine and Moab Khotsong mine. At Cooke 4 mine, the study examined the evolution of mining-induced fractures (M1-4) occurring ahead of the stope face during the extraction of the remnant shaft pillar. These fractures were monitored and delineated by a dense array of acoustic emission sensors that allowed hypocentres to be located with decimeter accuracy. Using this acoustic emission data, the DSeis team drilled and recovered the fractures, rock breccia and gouge using a sophisticated triple-tube drilling rig.

Apr 26, 2022

By Ronaldo Câmara Cozza

Iron aluminide alloy; Ball-cratering wear testing; Rolling abrasion; Wear volume; Coefficient of friction

Jul 31, 2018

By Cristiano José Scheuer

Experiments were carried out aiming to study the influence of micro-abrasive wear test variables and plasma treatment parameters, on the tribological characteristics of low-temperature plasma carburized AISI 420 steel. The first part of this study was conducted in order to evaluate the influence of abrasive particle size, normal load and counter body rotation speed on carburized sample wear behavior; and the second part was conducted in order to evaluate the treatment temperature and time effect on carburized samples wear behavior. Plasma carburizing treatments were performed at 8 and 12 h, for temperatures ranging from 350 to 500°C; and at constant temperatures of 400°C for times between 12 to 48h, and for 450°C for times of 4 to 16h. Micro-abrasive wear test were performed by mean of a calowear ball-cratering equipment using a polished ball of AISI 52100 steel rotating at 80, 120 and 160 rpm, for sliding distances from 2.6 to 104.2 m. Alumina abrasive particles with sizes of 0.05, 0.3 and 1.0 ?m were employed. The normal loads applied on this study were 0.1, 0.3 and 0.5 N. Carburized sample was characterized by mean of OM, XRD and hardness measurements. Worn crater characteristics were evaluated by confocal laser microscopy. Results showed that the transient wear regime prevails along the outer layer length (composed by Fe3C and ?’C), and the steady-state wear stabilizes in the diffusion layer region (composed by ?’C). It was verified that the wear rate and wear coefficient decreases with treatment temperature in the range of 350–450°C and increase for 500°C. It was also verified that the wear rate and wear coefficient decreases with treatment time in the range of 12–36 h (for 400°C cycle) and 4–12 h (for 450°C cycle), and increase for larger treatment times due the chromium carbide precipitation. It was also found that the wear coefficient increases with the increase of abrasive particle size, and decrease with the increase in counter body rotation speed and normal load. Lastly, the analysis of the worn craters indicates the occurrence of grooving and micro-rolling abrasion wear mechanisms.

Aug 17, 2017

By Cristiano José Scheuer

The effect of low-temperature plasma carburizing treatment on the micro-abrasive wear resistance of AISI 420 steel was investigated by mean of a CSM Calowear ball-cratering equipment. Carburized samples were treated at temperatures of 350, 400, 450 and 500°C for a fixed time of 12 h, using a gas mixture containing 99.5% (80% H2+20% Ar)+0.5% CH4. Micro-scale abrasive wear tests were conducted with a 25.4 mm AISI 420 steel sphere, using an abrasive suspension of alumina (Al2O3) with particle size of 1 ?m (abrasive concentration of 0.11 g/cm³). The contact normal force, abrasive flow and ball rotation speed were fixed at: 0.5 N, 0,2 drop/s, and 120 rpm. The wear craters were analyzed using a confocal laser microscope, Olympus OLS 3000. The wear analyses were performed for test times of: 30, 60, 90, 120, 180, 360, 540, 720 and 900 s (equivalent sliding distance: 0.84, 1.68, 2.52, 3.36, 5.04, 10.09, 15.14, 20.19 and 25.23 m, respectively). The results indicate that the wear coefficient in the outer layer and in the diffusion layer are different, being lower in the latter. It was also verified that the wear coefficient on the outer layer region decreases with increasing treatment temperature in the range of 350 to 450 °C, and increase again for 500ºC. The diffusion layer wear coefficient is similar for all the carburized samples. Finally, for all studied conditions, the analysis of the wear craters surface indicates the occurrence of grooving and micro-rolling abrasion wear modes.

Aug 8, 2018

By Piotr D. Moncarz

As major urban areas begin to run out of "good-terrain" for their expansion, they begin to claim high water-table areas within or adjacent to water fronts or swamps. Similarly, major infrastructure projects encroach on or cross high organic content areas. The associated major structures often require deep foundations located in soils investigated through core samples removed at a discrete number of locations. The investigation is nearly always preoccupied with soil mechanical properties, sometimes with soil non-organic chemistry for concrete and metal corrosion, seldom, if ever, for organic-chemistry and bio-conditions as related to concrete longevity. Not surprisingly so, bio-corrosion of concrete is one of the least understood phenomena by practicing civil engineers. This paper shows how low-iron, organic-rich sediments may trigger sulfate degradation of concrete, even when standard pre-construction chemical analyses indicate only a moderate sulfate level. The discussion is illustrated with a case of a pile foundation in the United States driven into marine channel sediments and sediment-derived fill material. The concrete piles lost their structural integrity due to secondary ettringite formation and depletion of iron in the cement paste. Disintegration of concrete occurred only where it contacted superficial marine sediments and sediment-derived fill material. Concrete in direct contact with seawater or native sand and silt materials appeared to be sound. Sediments in contact with the degraded concrete were highly anoxic and had a history of sewage contamination, contained low concentrations of total iron (<2%), Fe(III) (<0.3%) and moderate levels of sulfate (1500ppm), and exhibited high bacterial activity. This environment resulted in the microbial dissolution of Fe(lll)-rich ferrite in hardened cement paste. Iron depletion in the cement paste had made the concrete vulnerable to degradation by sulfate, even at moderate levels of sulfate concentrations in the sediments.

Jan 1, 2002

By T. N. Singh, Vasudev Singh

To explore and exploit the natural resources like oil, gas, economic mineral water drilling is still considered to be the reliable and economical method. When a drill bit penetrates the rock mass either by percussion or by rotary and may be some times a combination generates stress and thrust on the rock mass as well as on the drill bit. The strength and hardness of the rock govern the life of the drill bit and its runnage. Physico- Mechanical properties of rocks have great influence on drillability. It is observed that higher the strength of rock, reduce the life of the drill bit while drilling, ultimately decreases the drillability. An attempt has been made in the present paper to establish relation among various physicomechanical properties i.e. uniaxial compression strength, tensile strength, shear strength, Schmidt hardness and abrasivity with drillability of different rock types. The specific energy of each rock type has been calculated using micro-bit drilling. The rocks from different lithological succession were collected. The rock specimens were prepared according to the norms of International society of Rock Mechanics (ISRM).

Jan 1, 2008

By Joe D. Allison, Tom D. Baugh

The analysis for total cyanides (CN, or the cyanide due to the combination of free, weakly associated and refractory cyanide complexes) is required by most regulatory agencies for determination of effluent compliance. This method requires a distillation of the sample at low pH's and is most often sent to contract laboratories at a high time and monetary cost. This paper describes a new micro­distillation apparatus which allows for a multiple of CN,"' analyses to be carried out simultaneously saving both time and money. It can be used in the field, since only electrical power is required for the method. While not being appropriate for reporting values to the respective regulatory agencies as of yet, it is quite valuable for screening a large number of samples prior to submission of the samples to a contract lab for "official" reporting.

Jan 1, 1990

By Edward C. Dowling

The advance of science and technology influences the modern economy in countless ways. Older industries must adapt to changes in the marketplace, while new industries are born by applying new technology to meet consumer needs. In light of declining head grades and increased unit costs in the US minerals industry, new technological developments in the production environment are paramount to maintaining a competitive footing in the international marketplace. Micro-engineering research provides the transition between the knowledge base and the application of new technology on the production level. Economic considerations The primary goal of technical development in the production environment is to reduce unit operating costs. Simply stated, this is accomplished by improving operating efficiencies and productivities on the production level. The goal of micro-engineering research in the production environment is to evaluate promising technologies and develop the criteria necessary to apply them in operations. As such, this process is the first step toward innovation and discovery. Generally, the micro-engineering research is followed by macro-engineering development. In the production environment, there are generally more development projects than can be accomplished in a timely manner. Usually, this is the result of financial and human resource limitations. Consequently, it is necessary to prioritize the work such that the most beneficial projects are accomplished first. By performing a discounted cash flow analysis and using benefit-cost ratios (for non-mutually exclusive alter¬natives) or net present value criteria (for mutually exclusive alternatives), the projects can be rated from best to worst. In this way, the financial and human resources can be best allocated to first complete those projects giving the highest returns before moving on to other activities. Moreover, this information is a prerequisite for management to justify additional financial or human resources.

Jan 1, 1992

By S. P. Marsh, D. Banerjee

"Casting processes involve phenomena that occur on widely disparate length-scales. Simulation of macroscopic effects, such as heat transfer and convection, are generally addressed by solving the appropriate equations in discretized form on a finite-element mesh. Microscopic phenomena are described by micromodels that may be empirical or analytical in form. Coupling of phenomena in these two regimes is a critical issue in predicting microstructure and defect formation resulting from macroscopic process conditions. A formalism has been developed for expressing micromodels in a consistent manner using stereological parameters to quantify the geometric characteristics of the developing microstructure. This approach provides a robust and physically consistent method for coupling local micromodels with the macroscopic fields. The macroscopic state variables at each node serve as global constraints on the micromodels that are applied to a local unit volume. An outline of an equiaxed solidification model based on this approach is presented, along with preliminary simulation results. Coupling of convection and enthalpy effects between the micro and macro regimes is also discussed. IntroductionThe primary goal of casting simulations is to improve the reliability of cast parts while minimizing cost and development time. Effective simulations can speed up the mold design process and reduce the likelihood of defective parts by refining a particular casting process on a computer, reducing the dependence on cost- and time-intensive prototype castings. The challenge in developing effective simulations stems from the need to address physical processes that occur over a wide range of length-scales, from microscopic (atomic) and mesoscopic (microstructural) scales to macroscopic distances comparable to the size of the casting itself. Overviews of the various thermophysical phenomena and computational factors that are important in solidification modeling are provided in the literature by Rappaz [1] and Tseng et al. [2].Macroscopically, the solidification process is largely governed by the rate of heat flow from the alloy through the mold wall. Another important effect that occurs on the scale of the casting size is convective flow of the melt, which is driven by density-variations in the melt. Macroscopic calculations employ finite-element or finite-difference methods to solve the sets of equations that govern these effects, and the spatial resolution is determined by the grid spacings used for the calculations. Typical spatial resolutions are on the order of 10-2 to 10-3"" meters. This represents a compromise between the resolution required to simulate the continuum transport processes accurately, and the computational time required to model the entire solidification and cooling process."

Jan 1, 1994

By Vaughan R. Voller

"The wide range of length and time scales found in solidification processes are outlined and discussed. Methods for Direct Microstructure Simulation (DMS) are introduced. Key features in sharp interface and phase field models are presented. Concepts in micro-macro solidification modeling are covered. Basic details of microstructure and segregation models are provided. A description of a recent segregation micro-macro model is presented in detail.IntroductionA solidification process involves the containment of a liquid region, which, due to cooling, transforms over time to form a fully solid product. The development of the solid microstructure and the segregation of solute components during this transformation are controlled by phenomena that occur across a wide range of length and time scales. A ""successful"" model of a given solidification process needs to account for these phenomena. Standard models of solidification employ a discrete grid of node points and associated volume elements in the special domain, with a discrete time step to track the transient changes of nodal values, describing the composition and microstructure. Through the use of such models significant progress has been made towards a complete understanding of solidification process and phenomena (see the conference proceedings in Refs [1-9]). As solidification models become more sophisticated, however, they all run into the problem of resolving the full range of disparate space and time scales.Two approaches can deal with this problem1. Direct Microstructure Simulation (DMS) where the grid size and time step are chosen to scale with the smallest length and time scales of the given problem.2. Micro-macro modeling where the grid size and time step scale with the macroscopic process scale and phenomena at smaller scales are accounted for via sub-grid modeling and volume averaging.Currently full DMS of solidification is beyond the reach of available computer power and the application and development of micro-macro models is an important and critical research area."

Jan 1, 2001

By S. S. Yuan, Q. Z. Zhu, J. F. Shao

"This paper aims at enriching a homogenization-based anisotropic damage model for hard rocks under complex loading. A new damage criterion is proposed to capture material strain softening. Within the framework of irreversible thermodynamics, we are particularly concerned with two strongly coupled dissipative mechanisms: frictional sliding and damage by microcracking, which usually take place at cracks within cohesive geomaterials under compression. Focusing on the representative elementary volume containing multiple crack families, the free enthalpy of the matrix-cracks system is obtained. Importantly, a back-stress term is involved in the local stress applied to microcracks. This back stress plays the hardening/softening role in the friction criterion which is formulated at local scale. Strain hardening owns to the accumulation of frictional shearing and dilatancy while strain softening is caused by crack growth. The multiscale damage model is used to simulate laboratory tests on the Westerly granite under true triaxial compressions. INTRODUCTIONWhen subjected to compressive loads, hard rocks present nonlinear mechanical behaviors and induced material anisotropies. In that process, two main dissipative mechanisms have been largely identified: damage by crack growth and frictional sliding along closed crack faces, which are usually strongly coupled to each other on crack scale. Theoretical investigations have shown that the damagefriction coupling analyses allow explaining a large number of experimental phenomena involved in brittle or quasi-brittle materials. Concerning constitutive modeling, the standard Eshelby’s solution-based homogenization procedure for heterogeneous materials was recently applied successfully to describing the mechanical and poromechanical behaviors of cracked frictional solids."

Jan 1, 2015