CL for characterizing quartz and trapped fluid inclusions in mesothermal quartz veins: Muruntau Au ore deposit, Uzbekistan

2000 ◽  
Vol 64 (6) ◽  
pp. 1007-1016 ◽  
Author(s):  
T. Graupner ◽  
J. Götze ◽  
U. Kempe ◽  
D. Wolf
Keyword(s):  
Fluid Inclusions ◽  
Microstructural Analysis ◽  
Polarized Light ◽  
Video Camera ◽  
Quartz Veins ◽  
Digital Video Camera ◽  
Vein Formation ◽  
Primary Growth ◽  
Multi Stage ◽  
Growth Zoning

AbstractCombined cathodoluminescence (CL) and transmitted light microscopy were used to characterize quartz from flat and steeply dipping quartz veins and from veinlets in banded host rocks from the giant Muruntau Au quartz vein deposit, Kyzyl Kum Desert, western Uzbekistan. The CL examinations were carried out using a ‘hot-cathode’ CL microscope linked to a highly sensitive digital video camera. The multi-stage deformed flat quartz veins and the steeply dipping hydrothermal formations at Muruntau are characterized by quartz with different CL colours, internal structures and degree of secondary alteration. Primary growth zoning of quartz, indiscernible in conventional polarized light was found to occur only in steeply dipping veins. The bulk of the high-grade Au mineralized ‘central’ quartz veins is dominated by one generation of hydrothermal quartz; intense brecciation of these veins is indicated by the occurrence of fragments of zoned quartz crystals. Primary growth zoning in quartz may be revealed not only by variations in the intensity of blue CL and/or by primary fluid inclusions arranged within the zones, but also by secondary inclusions and recrystallization phenomena developed along boundary surfaces between the zones. Using the results from CL imaging and microstructural analysis of the quartz, fluid inclusions investigated earlier were assigned to genetic types; the evidence of probably primary inclusions is of considerable importance for further studies of the geochemical conditions during vein formation. Considering geological and mineralogical data, CL studies of vein quartz may help to reveal the history of precipitation, deformation and recrystallization processes in the Muruntau Au ore field.

Fluids in Hercynian Au veins from the French Variscan belt

1990 ◽  
Vol 54 (375) ◽  
pp. 231-243 ◽  
Author(s):  
M. C. Boiron ◽  
M. Cathelineau ◽  
J. Dubessy ◽  
A. M. Bastoul
Keyword(s):  
High Temperature ◽  
Fluid Inclusions ◽  
Genetic Relationships ◽  
Hydrothermal Systems ◽  
Gold Deposition ◽  
Variscan Belt ◽  
Quartz Veins ◽  
Multi Stage ◽  
Montagne Noire ◽  
Host Rocks

AbstractFluids, together with alteration and ore mineral assemblages, were studied in representative hydrothermal gold-bearing quartz veins from the western part of the Variscan belt in France (La Bellière, Montagne Noire district, Villeranges-Le Châtelet district, and Limousin province). Petrographic studies of the relationships between ores, fluid inclusions, microfracturing and quartz textures show that chronological and genetic relationships between gold deposition and fluid trapping may be very complex and difficult to establish for veins which show multi-stage fracturing and shearing. Systematic studies of secondary fluid inclusions in microcracks and recrystallized zones of the early quartz veins indicate two contrasting physical-chemical conditions: 1 relatively high temperature (250–400°C) and pressure (>1 kbar) event with CO2-CH4-H2S-N2 (±H2O-NaCl)-rich fluids related to the early sulphide deposition; 2 lower temperature (150–250°C) and pressure with aqueous fluids related to the late native-gold-sulphide (or sulphosalt) assemblage, which constitutes the economic ores in some deposits.In deposits where gold occurs predominantly in a combined state within arsenopyrite and pyrite (Châtelet and Villeranges), primary fluid inclusions in authigenic quartz combs cogenetic with arsenopyrite are almost purely aqueous (H2O-NaCl) and have a low salinity (1–4 wt. % NaCl). P-T conditions (150–250°C), nearly hydrostatic pressures) are similar to those of the second stage in the multi-stage quartz veins.Consideration of chemical equilibria in the C-O-H-N-S system using microthermometric and Raman spectrometric analysis for the fluids, together with data obtained from mineralogical studies, show that during gold deposition, fO2 was below hematite-magnetite buffer at Villeranges and around the Ni-NiO buffer at La Bellière and Montagne Noire. fS2 calculations based on H2S analyses are in good agreement with mineral assemblage estimates and close to that fixed by the pyrite-pyrrhotite boundary at high temperature. Ore fluid pH was significantly lower than in the host rocks as shown by the complete alteration of the host rocks into a quartz-K-mica assemblage. The data illustrate that during the late Hercynian, fluid circulation evolved from high P-T conditions, in some cases linked to late magma intrusions, towards conditions typical of later hydrothermal systems of the geothermal type.

High-resolution measurement of birefringent fine structure in living cells using a new polarized light microscope

1995 ◽  
Vol 53 ◽  
pp. 54-55
Author(s):  
Rudolf Oldenbourg
Keyword(s):  
Light Microscope ◽  
Fluorescent Dyes ◽  
Polarized Light ◽  
Processing System ◽  
Video Camera ◽  
Molecular Organization ◽  
Computer Assisted ◽  
Image Recording ◽  
Birefringent Crystal ◽  
Technological Advances

The recent renaissance of the light microsope is fueled in part by technological advances in components on the periphery of the microscope, such as the laser as illumination source, electronic image recording (video), computer assisted image analysis and the biochemistry of fluorescent dyes for labeling specimens. After great progress in these peripheral parts, it seems timely to examine the optics itself and ask how progress in the periphery facilitates the use of new optical components and of new optical designs inside the microscope. Some results of this fruitful reflection are presented in this symposium.We have considered the polarized light microscope, and developed a design that replaces the traditional compensator, typically a birefringent crystal plate, with a precision universal compensator made of two liquid crystal variable retarders. A video camera and digital image processing system provide fast measurements of specimen anisotropy (retardance magnitude and azimuth) at ALL POINTS of the image forming the field of view. The images document fine structural and molecular organization within a thin optical section of the specimen.

New polarized-light microscope for fast and orientation independent measurement of birefringent fine structure

1993 ◽  
Vol 51 ◽  
pp. 82-83
Author(s):  
Rudolf Oldenbourg
Keyword(s):  
Light Microscope ◽  
Polarized Light ◽  
Video Camera ◽  
Limited Range ◽  
Image Point ◽  
Computer Assisted ◽  
Optical Modulators ◽  
Anisotropic Structures ◽  
Long Time ◽  
Computer Assisted Image

The polarized light microscope has the unique potential to measure submicroscopic molecular arrangements dynamically and non-destructively in living cells and other specimens. With the traditional pol-scope, however, single images display only those anisotropic structures that have a limited range of orientations with respect to the polarization axes of the microscope. Furthermore, rapid measurements are restricted to a single image point or single area that exhibits uniform birefringence or other form of optical anisotropy, while measurements comparing several image points take an inordinately long time.We are developing a new kind of polarized light microscope which combines speed and high resolution in its measurement of the specimen anisotropy, irrespective of its orientation. The design of the new pol-scope is based on the traditional polarized light microscope with two essential modifications: circular polarizers replace linear polarizers and two electro-optical modulators replace the traditional compensator. A video camera and computer assisted image analysis provide measurements of specimen anisotropy in rapid succession for all points of the image comprising the field of view.

scholarly journals Ore Genesis at the Jinchang Gold–Copper Deposit in Heilongjiang Province, Northeastern China: Evidence from Geology, Fluid Inclusions, and H–O–S Isotopes

Minerals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 99 ◽  
Author(s):  
Shunda Li ◽  
Xuebing Zhang ◽  
Lingling Gao
Keyword(s):  
Fluid Inclusions ◽  
Copper Deposit ◽  
Northeastern China ◽  
Heilongjiang Province ◽  
Quartz Veins ◽  
Daughter Mineral ◽  
Rich Liquid ◽  
Three Stages ◽  
Stage 1 ◽  
Late Stages

The Jinchang gold–copper deposit is located in Eastern Heilongjiang Province,Northeastern China. The orebody comprises primarily hydrothermal breccias, quartz veins, anddisseminated ores within granite, diorite, and granodiorite. Three paragenetic stages are identified:early quartz–pyrite–arsenopyrite (Stage 1), quartz–pyrite–chalcopyrite (Stage 2), and latequartz–pyrite–galena–sphalerite (Stage 3). Gold was deposited during all three stages and Stage 1was the major gold-producing stage. Copper is associated with the mineralization but has loweconomic value. Fluid inclusions (FIs) within the deposit are liquid-rich aqueous, vapor-rich aqueous,and daughter-mineral-bearing types. Microthermometric data for the FIs reveal decreasinghomogenization temperatures (Th) and salinities of the ore-forming fluids over time. The Th forStages 1–3 of the mineralization are 421–479, 363–408, and 296–347 °C, respectively. Stage 1 fluidsin vapor-rich and daughter-mineral-bearing inclusions have salinities of 5.7–8.7 and 49.8–54.4 wt%NaCl equivalent, respectively. Stage 2 fluids in vapor-rich, liquid-rich, and daughter-mineral-bearinginclusions have salinities of 1.2–5.4, 9.5–16.0, and 43.3–48.3 wt% NaCl, respectively. Stage 3 fluids inliquid-rich and daughter-mineral-bearing inclusions have salinities of 7.9–12.6 and 38.3–42.0 wt% NaClequivalent, respectively. The estimated trapping pressures are 160–220 bar, corresponding toan entrapment depth of 1.6–1.2 km in the paleo-water table. Oxygen and hydrogen isotope data(δ18OV-SMOW = 8.6‰ to 11.4‰; δDV-SMOW = −92.2‰ to −72.1‰) suggest that the ore-forming fluidswere derived from magmatic fluids during the early stages of mineralization and subsequentlyincorporated meteoric water during the late stages. The sulfide minerals have δ34SVCDT values of0.2‰–3.5‰, suggesting that the sulfur has a magmatic origin. The Jinchang deposit is a typicalgold-rich gold–copper porphyry deposit.

scholarly journals Genesis of the Longmendian Ag–Pb–Zn Deposit in Henan (Central China): Constraints from Fluid Inclusions and H–C–O–S–Pb Isotopes

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-21
Author(s):  
Xinglin Chen ◽  
Yongjun Shao ◽  
Chunkit Lai ◽  
Cheng Wang
Keyword(s):  
Fluid Inclusions ◽  
Central China ◽  
Granitic Magma ◽  
Two Phase ◽  
Quartz Veins ◽  
The North ◽  
Granitic Magmatism ◽  
Polymetallic Sulfides ◽  
Homogenization Temperatures ◽  
Stage 1

The Longmendian Ag–Pb–Zn deposit is located in the southern margin of the North China Craton, and the mineralization occurs mainly in quartz veins, altered gneissic wallrocks, and minor fault breccias in the Taihua Group. Based on vein crosscutting relations, mineral assemblages, and paragenesis, the mineralization can be divided into three stages: (1) quartz–pyrite, (2) quartz–polymetallic sulfides, and (3) quartz–carbonate–polymetallic sulfides. Wallrock alteration can be divided into three zones, i.e., chlorite–sericite, quartz–carbonate–sericite, and silicate. Fluid inclusions in all Stage 1 to 3 quartz are dominated by vapor-liquid two-phase aqueous type (W-type). Petrographic and microthermometric analyses of the fluid inclusions indicate that the homogenization temperatures of Stages 1, 2, and 3 are 198–332°C, 132–260°C, and 97–166°C, with salinities of 4.0–13.3, 1.1–13.1, and 1.9–7.6 wt% NaCleqv, respectively. The vapor comprises primarily H2O, with some CO2, H2, CO, N2, and CH4. The liquid phase contains Ca2+, Na+, K+, SO42−, Cl−, and F−. The sulfides have δ34S=–1.42 to +2.35‰ and 208Pb/204Pb=37.771 to 38.795, 207Pb/204Pb=15.388 to 15.686, and 206Pb/204Pb=17.660 to 18.101. The H–C–O–S–Pb isotope compositions indicate that the ore-forming materials may have been derived from the Taihua Group and the granitic magma. The fluid boiling and cooling and mixing with meteoric water may have been critical for the Ag–Pb–Zn ore precipitation. Geological and geochemical characteristics of the Longmendian deposit indicate that the deposit is best classified as medium- to low-temperature intermediate-sulfidation (LS/IS) epithermal-type, related to Cretaceous crustal-extension-related granitic magmatism.

AN OBJECT LOCATION SPECIFYING METHODOLOGY USING ONE CAMERA

2001 ◽  
Vol 09 (06) ◽  
pp. 685-702 ◽  
Author(s):  
WIRAT KESRARAT ◽  
THOTSAPON SORTRAKUL
Keyword(s):  
Image Processing ◽  
Image Plane ◽  
Video Camera ◽  
Object Location ◽  
Target Point ◽  
Target Area ◽  
Digital Video Camera ◽  
The World ◽  
The Difference ◽  
Point Center

This research proposed a methodology for specifying the location of an object with image processing. The objectives of this methodology are to capture the target area, and specify the location of the object by using image. In order to locate the dropping object on the image plane efficiently, consecutive images are analyzed and a threshold operation is proposed. Because the accuracy of the dropping objects location on the difference of consecutive images image plane is usually influenced by noise. Moreover, transformation unit is adopted to map the XY coordinate on image plane into the world coordinate for an accuracy of the dropping objects position. After we get the actual XY coordinate of the dropping object, we can find the distance from the target point (center) and clock direction of the dropping object related to the center also. In addition, by using one digital video camera set on the tower and pan to capture the image on the target area to detect the dropping object from the air to the ground. It made the proposed methodology provide easier portability to detect the dropping object in any area.

scholarly journals AFM investigation of hyaline cartilage’s surface destruction

2016 ◽  
Author(s):  
Mikhail Ihnatouski ◽  
Dmitriy Karev ◽  
Boris Karev ◽  
Jolanta Pauk ◽  
Kristina Daunoravičienė
Keyword(s):  
Video Camera ◽  
Optical Microscope ◽  
Collagen Fibers ◽  
Force Microscopy ◽  
Digital Video Camera ◽  
Atomic Force ◽  
Reflected Light ◽  
Longitudinal Orientation ◽  
Chronic Progressive Disease ◽  
Surface Destruction

Introduction: Osteoarthritis is a chronic, progressive disease. The aim of this paper is presenting the AFM investigation of cartilage in relation to the assessment of degenerative changes in the surface of hyaline cartilage. It can be useful in choosing the most effective methods of therapy. Methods: Samples were taken from the cartilage surface of the femoral head after its removal during total hip arthroplasty. Images of the surface of the sample were obtained using an optical microscope equipped with a digital video camera, in the reflected light and by atomic force microscopy. Results: The longitudinal orientation of the collagen fibers and sub-fibers beams on the surface, up to a diameter of 50 nm are identified in non-destroyed area sites. Conclusions: Images of the destroyed areas displaying separately passing collagen fibers, strongly exposed to the surface: the size measured and found substructure.

A digital video camera system

1990 ◽  
Vol 36 (4) ◽  
pp. 3866-3876 ◽  
Author(s):  
A. Morimura ◽  
K. Uomori ◽  
Y. Kitamura ◽  
A. Fujioka ◽  
J. Harada ◽  
...  
Keyword(s):  
Digital Video ◽  
Video Camera ◽  
Camera System ◽  
Digital Video Camera ◽  
Video Camera System
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