Lithology discrimination from physical rock properties

Geophysics ◽  
2002 ◽  
Vol 67 (2) ◽  
pp. 573-581 ◽  
Author(s):  
Miguel Bosch ◽  
Maaria Zamora ◽  
Widya Utama
Keyword(s):  
Discriminant Analysis ◽  
Physical Properties ◽  
Survey Methods ◽  
Mass Density ◽  
Shear Velocity ◽  
Velocity Shear ◽  
Rock Properties ◽  
Crustal Rocks ◽  
Graphic Analysis ◽  
The Media

The estimation of lithology from multiple geophysical survey methods needs to be addressed to develop advanced tomographic methods. An initial requirement for lithology discrimination is that lithology should be discriminable from the media properties physically related to the geophysical observations. To test this condition for different combinations of the most common crustal rocks, we performed several lithology discrimination exercises on rock samples under laboratory conditions. The physical properties included mass density, compressional velocity, shear velocity, electric conductivity, thermal conductivity, and magnetic susceptibility. A categorical description of the sample lithology was followed; hence, the inference consisted of predicting the sample rock category (lithotype) membership. The joint information provided by the physical properties of the rocks allowed us to discriminate the sample lithotype correctly, with an overall success rate of 100% in the most favorable situation and over 85% in the least favorable situation. We obtained successful classification results for a variety of common lithotypes (granite, gabbro, limestone, tuff, marble, basalt, and gneiss) using three common classification methods: clustering analysis, Gaussian classification, and discriminant analysis. Although discrimination was positive with each of these multivariate classification techniques, discriminant analysis showed some advantages for the classification and graphic analysis of the data. These results support our postulate that lithology can be estimated reliably if multiple geophysical observations are considered jointly.

scholarly journals Pressure and fluid saturation prediction in a multicomponent reservoir using combined seismic and electromagnetic imaging

Geophysics ◽  
2003 ◽  
Vol 68 (5) ◽  
pp. 1580-1591 ◽  
Author(s):  
G. Michael Hoversten ◽  
Roland Gritto ◽  
John Washbourne ◽  
Tom Daley
Keyword(s):  
Electrical Conductivity ◽  
Water Saturation ◽  
Saturation Pressure ◽  
Shear Velocity ◽  
Velocity Shear ◽  
Rock Properties ◽  
Velocity Change ◽  
Archie’S Law ◽  
Fluid Saturation ◽  
Compressional Velocity

This paper presents a method for combining seismic and electromagnetic (EM) measurements to predict changes in water saturation, pressure, and CO2 gas/oil ratio in a reservoir undergoing CO2 flood. Crosswell seismic and EM data sets taken before and during CO2 flooding of an oil reservoir are inverted to produce crosswell images of the change in compressional velocity, shear velocity, and electrical conductivity during a CO2 injection pilot study. A rock‐properties model is developed using measured log porosity, fluid saturations, pressure, temperature, bulk density, sonic velocity, and electrical conductivity. The parameters of the rock‐properties model are found by an L1‐norm simplex minimization of predicted and observed differences in compressional velocity and density. A separate minimization, using Archie's law, provides parameters for modeling the relations between water saturation, porosity, and electrical conductivity. The rock‐properties model is used to generate relationships between changes in geophysical parameters and changes in reservoir parameters. Electrical conductivity changes are directly mapped to changes in water saturation; estimated changes in water saturation are used along with the observed changes in shear‐wave velocity to predict changes in reservoir pressure. The estimation of the spatial extent and amount of CO2 relies on first removing the effects of the water saturation and pressure changes from the observed compressional velocity changes, producing a residual compressional velocity change. This velocity change is then interpreted in terms of increases in the CO2/oil ratio. Resulting images of the CO2/oil ratio show CO2‐rich zones that are well correlated to the location of injection perforations, with the size of these zones also correlating to the amount of injected CO2. The images produced by this process are better correlated to the location and amount of injected CO2 than are any of the individual images of change in geophysical parameters.

Understanding how overpressure affects the physical properties of sandstones

Geophysics ◽  
2021 ◽  
pp. 1-33
Author(s):  
Tongcheng Han ◽  
Shengbiao Liu ◽  
Li-Yun Fu ◽  
Han Yan
Keyword(s):  
Remote Sensing ◽  
Electrical Conductivity ◽  
Aspect Ratio ◽  
Physical Properties ◽  
Pore Pressure ◽  
Wave Velocity ◽  
Compressional Wave ◽  
Rock Properties ◽  
Compressional Wave Velocity ◽  
Crustal Rocks

Overpressure is one of the major difficulties we have to face when exploring the deep earth. Geophysical remote sensing methods, especially seismic and electrical methods, are widely employed to predict overpressure for de-risking the drilling of deep boreholes in the earth’s crust. However, there are major uncertainties in relating the measured geophysical parameters to the physical properties of crustal rocks, needed for reliable overpressure estimation. We address this knowledge gap through dedicated laboratory measurements of elastic velocity, electrical conductivity and porosity with increasing pore pressure and the analyses and interpretation of the experimental results. We find a linear increase in the porosity, and an exponential increase and decrease in the electrical conductivity and compressional wave velocity, respectively with increasing pore pressure. We also find an exponential reduction in the cementation exponent and effective pore aspect ratio inverted from the pore pressure induced electrical conductivity and compressional wave velocity, respectively. We further demonstrate that the changing cementation exponent and effective pore aspect ratio by increasing pore pressure affects more significantly the electrical and elastic rock properties than does by dilating porosity. The results not only strengthen our understanding of the influencing mechanism of overpressure on the physical properties of crustal rocks, but also provide new insights for the more reliable detection of overpressure zones from geophysical remote sensing.

UTILIZATION OF RAWAPENING PEAT FOR NUTRIENT BLOCK AS A MEDIA NURSERIES Anthocephalus cadaba and Paraserianthes falcataria

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
E. Hanggari Sittadewi., dkk
Keyword(s):  
Plant Growth ◽  
Physical Properties ◽  
Environmental Degradation ◽  
Leaf Growth ◽  
Rehabilitation Program ◽  
Paraserianthes Falcataria ◽  
Land Rehabilitation ◽  
Mining Areas ◽  
Growing Medium ◽  
The Media

Nutrient Block is a growing medium product in the form of a square (25 x 25 cm) or cylindrical (diameter = 20 cm, height = 25 cm) made of peat which has been composted, plus adhesive gypsum or tapioca waste. Nutrient Block is designed to support the post mining land rehabilitation program that is now threatening the environmental degradation in mining areas. Nutrient Block products has been proved good for growth because of the media in addition to having physical properties that are capable of storing large amounts of water, contain enough nutrients in the form available to plants,so it can support plant growth. Results of the Nutrient Block application test to Jabon (Anthocephalus cadaba) and Sengon (Paraserianthes falcataria) plants showed that good performance, both plant height and diameter of trees and leaf growth in plants Jabon appear healthy and getting wider.keywords: nutrient block, post-mining land rehabilitation. Paraserianthes falcataria, Anthocephalus cadaba

scholarly journals Chemical and Physical Properties of Some Hazelnut Varieties Grown in Portugal

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1476
Author(s):  
Ana Cristina Ferrão ◽  
Raquel P. F. Guiné ◽  
Elsa Ramalhosa ◽  
Arminda Lopes ◽  
Cláudia Rodrigues ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Physical Properties ◽  
Water Activity ◽  
Induction Time ◽  
Oxidation Stability ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Nutritional Characteristics ◽  
Physical And Chemical ◽  
And Chemical Properties

Hazelnuts are one of the most appreciated nuts worldwide due to their unique organoleptic and nutritional characteristics. The present work intended to analyse several physical and chemical properties of different hazelnut varieties grown in Portugal, namely Tonda de Giffoni, Grada de Viseu, Segorbe, Longa de Espanha, Butler, Gunslebert, and Negreta. In general, the results revealed statistically significant differences between the varieties under study. The Gunslebert had more elongated hazelnuts and with heavier shelled fruits, while the kernels of the Grada de Viseu revealed to be heavier. Grada de Viseu was harder in the shell, Gunslebert had a harder core, and Segorbe was more resistant to fracture. Fat was the more representative component for all varieties and in some cases the values of moisture and water activity were over the recommended amount (≥0.62). Tonda de Giffoni was the variety with the highest induction time, indicating the highest oxidation stability. Moreover, discriminant analysis revealed that the variables more important to distinguish the varieties were protein (λ = 0.007) and water activity (λ = 0.010). The results of this study help to better understand the differences between some hazelnut varieties that are cultivated in Portugal, which gives important hints for all players in the hazelnut sector.

scholarly journals Physical Properties of Electropolished CoCrMo Alloy Coated with Biodegradable Polymeric Coatings Releasing Heparin after Prolonged Exposure to Artificial Urine

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2551
Author(s):  
Wojciech Kajzer ◽  
Janusz Szewczenko ◽  
Anita Kajzer ◽  
Marcin Basiaga ◽  
Joanna Jaworska ◽  
...  
Keyword(s):  
Physical Properties ◽  
Crevice Corrosion ◽  
Mass Density ◽  
Polymer Coatings ◽  
Metal Substrate ◽  
Reference Level ◽  
Polymeric Coatings ◽  
Initial State ◽  
Cocrmo Alloy ◽  
Artificial Urine

In this study, we aimed to determine the effect of long-term exposure to artificial urine on the physical properties of CoCrMo alloy with biodegradable heparin-releasing polymeric coatings. Variants of polymer coatings of poly(L,L-lactide-ɛ-caprolactone) (P(L,L-L/CL)) and poly(D,L-lactide-ɛ-caprolactone) (P(D,L-L/CL)) constituting the base for heparin-releasing (HEP) polyvinyl alcohol (PVA) coatings were analyzed. The coatings were applied by the dip-coating method. Heparin was used to counteract the incrustation process in the artificial urine. The study included tests of wettability, resistance to pitting and crevice corrosion, determination of the mass density of metal ions penetrating into the artificial urine, and the kinetics of heparin release. In addition, microscopic observations of surface roughness and adhesion to the metal substrate were performed. Electrolytically polished CoCrMo samples (as a reference level) and samples with polymer coatings were used for the tests. The tests were conducted on samples in the initial state and after 30, 60, and 90 days of exposure to artificial urine. The analysis of the test results shows that the polymer coatings contribute by improving the resistance of the metal substrate to pitting and crevice corrosion in the initial state and reducing (as compared with the metal substrate) the mass density of metal ion release into the artificial urine. Moreover, the PVA + HEP coating, regardless of the base polymer coatings used, contributes to a reduction in the incrustation process in the first 30 days of exposure to the artificial urine.

Discriminant analysis-based modeling of cotton fiber and yarn properties

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Baneswar Sarker ◽  
Shankar Chakraborty
Keyword(s):  
Discriminant Analysis ◽  
Physical Properties ◽  
Cotton Fiber ◽  
Fiber Strength ◽  
Natural Fibers ◽  
Content Type ◽  
Fiber Properties ◽  
Yarn Properties ◽  
Fiber Fineness ◽  
Genetic And Environmental Factors

Purpose Like all other natural fibers, the physical properties of cotton also vary owing to changes in the related genetic and environmental factors, which ultimately affect both the mechanics involved in yarn spinning and the quality of the yarn produced. However, information is lacking about the degree of influence that those properties impart on the spinnability of cotton fiber and the strength of the final yarn. This paper aims to discuss this issue. Design/methodology/approach This paper proposes the application of discriminant analysis as a multivariate regression tool to develop the causal relationships between six cotton fiber properties, i.e. fiber strength (FS), fiber fineness (FF), upper half mean length (UHML), uniformity index (UI), reflectance degree and yellowness and spinning consistency index (SCI) and yarn strength (YS) along with the determination of the respective contributive roles of those fiber properties on the considered dependent variables. Findings Based on the developed discriminant function, it can be revealed that FS, UI, FF and reflectance degree are responsible for higher YS. On the other hand, with increasing values of UHML and fiber yellowness, YS would tend to decrease. Similarly, SCI would increase with higher values of FS, UHML, UI and reflectance degree, and its value would decrease with increasing FF and yellowness. Originality/value The discriminant functions can effectively envisage the contributive role of each of the considered cotton fiber properties on SCI and YS. The discriminant analysis can also be adopted as an efficient tool for investigating the effects of various physical properties of other natural fibers on the corresponding yarn characteristics.

ATI CP GRADE 11 TITANIUM

Alloy Digest ◽  
2021 ◽  
Vol 70 (6) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Heat Treating ◽  
Chemical Processing ◽  
Commercially Pure ◽  
Excellent Corrosion Resistance ◽  
Continuous Service ◽  
The Media ◽  
Titanium Grade ◽  
Grade 11

Abstract ATI CP Grade 11 Titanium is an unalloyed titanium grade that contains 0.12-0.25% Pd. This palladium-containing alloy extends the range of application of commercially pure (CP) titanium in HCl, H3PO4, and H2SO4 solutions. ATI CP Grade 11 Titanium is used in applications requiring excellent corrosion resistance in chemical processing or storage applications where the media is mildly reducing or fluctuates between oxidizing and reducing. It can be used in continuous service up to 425 °C (795 °F) and in intermittent service up to 540 °C (1000 °F). This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: Ti-179. Producer or source: ATI.

Students’ Spiraling Silence and Willingness to Communicate about Religion in the United States: An Exploration of the Media’s Role in Stigmatizing Religion

2013 ◽  
Vol 2 (1) ◽  
pp. 1-27
Author(s):  
Mariam F. Alkazemi
Keyword(s):  
United States ◽  
Survey Methods ◽  
Media Exposure ◽  
The United States ◽  
Willingness To Communicate ◽  
Spiral Of Silence ◽  
Majority Opinion ◽  
Silence Effect ◽  
The Media ◽  
The Spiral Of Silence

The spiral of silence effect describes individuals’ tendency to silence minority opinions, whilst using the media to gauge majority opinion. While the spiral of silence effect has been explored in controversial political contexts, the phenomenon has not been scrutinized in its relation to religious communication. The current study applies this concept to further the current understanding of communication as it applies to religion. A questionnaire was distributed electronically to 94 students at a large university in the southeastern United States. Using survey methods, this paper finds that religiosity is positively correlated to willingness to communicate about religion. This paper also finds that media exposure is not related to either willingness to communicate about religion or religiosity.

scholarly journals Determination of Physical Properties, Moisture Absorption Process and Aerodynamic Properties of Grain and Cluster Straw of Two Wheat Cultivars

2020 ◽  
Vol 68 (5) ◽  
pp. 831-840
Author(s):  
Mohammad Jafari ◽  
Gholam Reza Chegini ◽  
Javad Khazaei
Keyword(s):  
Physical Properties ◽  
Drag Coefficient ◽  
Moisture Absorption ◽  
Mass Density ◽  
Terminal Velocity ◽  
Wheat Cultivars ◽  
Projected Area ◽  
Drag Forces ◽  
Aerodynamic Properties

In this study, physical properties of grain and cluster straw including geometric dimensions, moisture absorption and aerodynamic properties of two wheat cultivars were investigated. The effect of cultivar on width, thickness, geometric diameter, spheroid coefficient and mass density was significant at 1% probability level whilst there were no significant effect on grain projected area, length and weight. Moisture absorption of the grains was rapid during the first 30–40 min and then turned to zero. The terminal velocity of wheat grain and straw in three shapes was measured by calculating the projected area in horizontal, lateral and perpendicular directions and then, the drag coefficient was obtained by the equilibrium of the gravity and drag forces at the terminal velocity. Results also showed that increasing moisture content resulted in an increase in the terminal velocity and a decrease in the drag coefficient. Results obtained in this study can be used in designing wheat- cluster straw separation and processing.

scholarly journals The Influence of Kaolinite - Illite toward mechanical properties of Claystone

2019 ◽  
Vol 11 (1) ◽  
pp. 440-446
Author(s):  
Supandi Supandi ◽  
Zufialdi Zakaria ◽  
Emi Sukiyah ◽  
Adjat Sudradjat
Keyword(s):  
Mechanical Properties ◽  
Physical Properties ◽  
Void Ratio ◽  
Correlation Coefficients ◽  
Physical And Mechanical Properties ◽  
Friction Angle ◽  
Engineering Properties ◽  
Rock Properties ◽  
Triaxial Tests ◽  
Mineralogical Characteristics

Abstract This study investigates the relationship between clay minerals (kaolinite and illite) and rock properties of the claystone, including both mechanical (cohesion, friction angle, stress, and strain) and physical properties (natural water content, void ratio, and wet density), belonging to Warukin Formation of Kalimantan, Indonesia. Mineralogical characteristics of these rocks were studied using petrological and X-ray diffraction techniques, whereas the mechanical and physical properties were tested by conducting uniaxial and triaxial tests. Relationship among the variables was determined using correlation coefficients. It was observed that the mineralogy of the rocks pose strong constraints on their engineering properties. The results showed that an increase in illite content decreases cohesion, friction angle, strength, and safety factor; and increases natural moisture content, void ratio, and wet density. Although illite content of these rocks was just about 10.8% of the total minerals, it has significantly contributed to the modification of physical and mechanical properties. In contrast, kaolinite did not have a significant impact; since the correlation between various parameters was significantly low (correlation coefficient was much less, <0.3). Therefore while selecting the materials for geotechnical engineering applications, illite emerges as a safer alternative to kaolinite, especially when its concentration is less than 10.8% of the total rock mass.

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