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How do you determine the mineral compositions of a basalt?
by XRD.
What is the mineral composition of a residual soil?
The mineral composition of a residual soil differs and can be determined by X-ray diffraction (XRD) tests
What kind of technology is used in geology?
A huge number of various technologies are used in the geosciences. LiDAR, Radar, Remote Sensing, GIS, X-ray fluorescence spectrometry (XRF), X-ray difraction spectrometry (XRD), material mechanics, flume tables, analog materials, ground penetrating radar, seismic tomography, cosmogenic isotope dataing, Uranium lead dating, stable isotope geochemistry .....
How do miners find minerals in the rocks?
The simplest way is to look at the rock. Many of the most common minerals are very easy to identify. Criteria like the colour, cleavage, hardness, luster, reaction to certain chemical and many other qualities give hints. Most rocks are made of a quartz, calcite, and feldspars. These are fairly simple to tell apart. There are thousands of different minerals though (but most are very rare). Also, under a microscope, thin sections of rocks can be made. Again the minerals all have unique properties that can be seen here. If minerals are too small to you can use XRD (X-Ray diffeaction). This involves hitting a sample of the rock with x-rays and measuring the x-rays that bounce off. Each mineral has a distinct pattern for how it gives off x-rays interact with it, so the result gives an idea of which minerals are present and in what amounts
How do you use echolocation in a sentences?
Bats use echolocation.
How do you determine the identity of a green crusty mineral on a stalagmite?
by the use of XRD.
How do you determine the mineral compositions of a basalt?
by XRD.
What does the acronym XRD stand for?
XRD stands for Extensible Resource Descriptor Sequence. It is a version of the XML format that allows users to discover various metadata aspects from documents being used.
What is the mineral composition of a residual soil?
The mineral composition of a residual soil differs and can be determined by X-ray diffraction (XRD) tests
Where does ionization energy come from with XRD?
what or where is that in the first place and second what kind of not geek person in the right state of mond would even ask that????
What is the disadvantage and advantage of using XRD instead of XRF?
Actually the type of compound and its molecular structure designates which technique will be more effective. XRD is used to measure crystalline compounds and provides a quantitative and qualitative analysis of compounds that cannot be measured by other means.XRF is a technique that is used to measure the percentage of metals within inorganic matrices such as cement and metal alloys. XRF is an especially useful research and development tool in construction industries. This technique is extremely useful for determining the make-up of these materials, allowing for higher-quality cements and alloys to be developed. Disadvantage : XRD has some size limitations. It is much more accurate for measuring large crystalline structures rather than small ones. Small structures that are present only in trace amounts will often go undetected by XRD readings, which can result in skewed results.
What is the bragg diffraction angle for the 001 axis of germanium?
According to RADS, the XRD software employed by Bede Scientific in the 1990s, the Bragg angle for Ge at the Miller Index (0,0,1) is 32.9959 degrees.
What is external standard method for XRD technique and how to calculate it?
External Standard Method is the process of finding the quantity of phases present in a mixture by comparing the integrated intensity of the peaks in the mixture with that of a pure phase.
What is Differentiate between polymorphism and isomerism?
Polymorphism and Allotropy are same thing. Polymorphism is used for compounds and the allotropy is reserved for elements. You can go for XRD to check the crystal structure and their composition to distinguish.
What is the difference between working principle of XRF and XRD?
XRD and XRF are highly complementarymaterials analysis methods which, when usedtogether, greatly improve the accuracy ofphase identification and quantitative analysis.The combination of both methods provides anincrease in the numbers of measured parameters,which means that fewer assumptions are neededfor analysis. This in turn provides not only greateraccuracy of results, but also increases the rangeof samples that can be measured to includesamples about which little or nothing is known inadvance.XRD is the most direct and accurate analyticalmethod for determining the presence andabsolute amounts of mineral species in a sample.Ambiguous results may be obtained however, ifthe sample chemistry and/or origin are unknown.In these cases phase identification can be difficult;in particular, isostructural phases with similarchemical composition will give similar powderdiffraction patterns.In contrast to XRD, XRF provides highly accurateinformation about the elemental compositionof a sample, but it cannot deliver direct phaseinformation. Mass-balance calculations may givesufficient phase information in some cases, butcan also lead to meaningless results e.g. in thepresence of polymorphs.It is the complimentary nature of the XRD andXRFmethods which makes them a valuabletool for quantitative phase analysis in numerousapplications ranging from scientific researchto industrial high-throughput quality control.Particularily in mineralogical and geologicalapplication areas, the combined use of XRD andXRF is booming, offering completely new insightsinto materials and processes. Typical examplesare the cement, minerals & mining, and industrialminerals industries, where the quality of productsand / or efficiency of processes is governed byboth phase and elemental composition. Thecombined use of XRD and XRF methods allowsthe reliable analysis of materials, for which theindividual methods fail to deliver accurate andreliable results.Page 2Quantitative phase and element analysis ofhost/waste rocks and tailings is an importantapplication in the minerals and mining industrywith respect to both process optimization (e.g.acid leaching) and environmental protection:Mining and milling operations are responsiblefor the production of billions of tonnes of wasterock and finely crushed tailings worldwide. Animportant application is the knowledge of therelative amounts of the minerals with acid-producing or neutralization potential for successfulacid-base accounting with respect to both theleaching process as well as acid mine drainage,with its detrimental effects on environment.As an example, we report combined XRD-XRFanalysis of an intrusive rock with unknowncomposition. Of particular interest was itsclassification by mineral content as well asthe detection and accurate quantification ofpotentially present minerals with significant acid-producing or neutralization potential.Powder diffraction data were recorded using aD4 ENDEAVOR powder diffractometer equippedwith a LynxEyeTMdetector (Fig. 1); the totalmeasurement time required was about 5 minutes.For phase identification and quantification,the DIFFRACplussoftware packages EVA,SEARCH and TOPAS were used. StandardlessXRFmeasurements on the same sample wereperformed with the S4 PIONEER and theSPECTRAplussoftware (Fig. 1).Fig. 1: D4 ENDEAVOR diffractometer (right)and S4 PIONEER spectrometer (left) connectedwith conveyer belt. The D4 is equipped withSuper Speed LynxEyeTMdetector.Fig. 2: EVA phase identification results.1) Phase identificationFig. 2 and Tab. 1 show the XRD powder data andthe phase identification results. The major rockforming minerals plagioclase, quartz, diopsideand muscovite are easily and correctly identifiedin a single default run. Note, that the highlysensitive SEARCH algorithm clearly prefers albite(Na-plagioclase) versus anorthite (Ca-plagioclase)as a result of the slightly different latticeparameters of both plagioclase solid solutionend members. Best SEARCH figure-of-meritsobtained for the individual phases were 0.65 and1.48, respectively. Neither ore minerals nor anyK-feldspars or feldspathoids could be detected.Tab. 1: EVA phase identification results.SS-VVV-PPPPCompound Name00-009-0466 (*)Albite00-041-1480 (I)Albite, calcian03-065-0466 (C)Quartz low, syn01-087-0700 (C)Diopside, syn01-089-5402 (C)Muscovite 2M1Page 3Fig. 3: EVA combined XRD-XRF results -comparison of calculated (column "SQD") versusobserved (column "XRF") element concentrations.The difference is given in column "Delta".2) Combined XRD-XRF analysisTo confirm the phase identification results,and to obtain semi-quantitative phase amountestimates consistent with the actual elementalcomposition of the sample, combined XRD-XRFanalysis has been performed with EVA. EVAenables semi-quantitative analysis based on thereference-intensity-ratio (RIR) method using bothXRD as well as XRFdata simultaneously: Onscaling the maximum intensities of the ICDD PDFpatterns to the observed peaks in the powderpattern, EVA calculates both phase and elementconcentrations, and compares the latter with theactually measured element concentrations.Element concentrations as obtained by XRF andused by EVA are provided in Tab. 2. Already atfirst glance, the XRF data fully confirm the absenceof any significant acid-producing ore mineralsdue to the minor concentrations found for heavyelements and the absence of sulphur.Tab. 2: Element concentrations [%] as obtained by XRF.Oxygen47.7Silicon30.0Aluminum 9.75Sodium6.1Calcium3.66Magnesium 0.456Iron1.35Potassium0.271Phosphorus 0.114Chlorine0.0445Titanium0.252Manganese 0.0173Cobalt0.0182Nickel0.0142Strontium0.0595Zirconium0.0143Barium0.0258Wolfram0.101The results for combined XRD-XRF analysis withEVA are shown in Fig. 3 and Tab. 3. The high Navs. Ca concentrations confirm the presence of Na-plagioclase as found by XRD (diopside accountsfor about 60% of the total Ca, as calculatedby EVA). The present Na-plagioclase is mostsuccessfully modelled using two albite phaseswith different Ca amounts. Note the excellentagreement found between the calculated andobserved element concentrations, which is betterthan 1% for all elements, and therefore confirmsthe correctness of the XRD phase identificationresults for all phases.The accuracy of the RIR method is limited byseveral factors such as preferred orientationeffects and the quality of the ICDD PDF data used(e.g. quality of relative intensities, I/Icor values,idealized chemical formula).Tab. 3: EVA semi-quantitative phase analysisresults based on combined XRD-XRF usingreference intensities as given in the ICDD PDFpatterns.SS-VVV-PPPPCompound NamePhaseamounts00-009-0466 (*)Albite58.2%00-041-1480 (I)Albite, calcian15.4%03-065-0466 (C) Quartz low, syn14.0%01-087-0700 (C) Diopside, syn9.9%01-089-5402 (C) Muscovite 2M12.6%The most accurate quantitative results will beobtained from a TOPAS Rietveld refinement. Thecombined XRD-XRF results obtained are of highvalue for defining the refinement model.Page 4BRUKER AXS, INC.5465 EAST ChERYL pARKwAYMADISON, wI 53711-5373USATEL. (+1) (800) 234-XRAYTEL. (+1) (608) 276-3000FAX (+1) (608) 276-3006EMAIL info@bruker-axs.comwww.bruker-axs.comAll configurations and specifications are subject to change without notice. Order No. L88-E00058. © 2006 BRUKER AXS GmbH. Printed in Germany.BRUKER AXS GMBhOESTLIChE RhEINBRUECKENSTR. 49D-76187 KARLSRUhEGERMANYTEL. (+49) (0)(721)595-2888FAX (+49) (0)(721)595-4587EMAIL info@bruker-axs.dewww.bruker-axs.deBRUKER AXS K.K3-9-A, MORIYA, KANAGAwAYOKOhAMA, KANAGAwA 221-0022JApANTEL. (+81) 45 453 1963FAX (+81) 45 440 0757www.bruker-axs.com3) Quantitative TOPAS refinementQuantitative Rietveld analysis has beenperformed using TOPAS, the results are shownin Fig. 4 and Tab. 4. For the final refinementtwo Na-plagioclases with different compositionshave been used to model the data to take theelemental analysis results into account: Albite (0%Ca) and Oligoclase (25% Ca).From the results in Tab. 4 the followingconclusions can be drawn:1. The sample can be unambiguously classified asa quartzdiorite according to Streckeisen, see Fig. 5.2. Combined XRD-XRF analysis and TOPASRietveld refinement can allow a distinction of evenneighboring plagioclase solid solution members(here albite and oligoclase) if present in sufficientamounts.The present sample can be characterised asa rock with insignificant acid producing orneutralisation potential. Remarkable is the easyand reliable determination of the plagioclase typefor estimation of the neutralisation potential. Thisability is of particular interest, as anorthite hasan about 14x higher neutralisation potential thanalbite (e.g. Jambor et al., 2002).Fig. 4: Quantitative TOPAS refinement results.Tab. 4: Quantitative TOPAS refinement results.Compound NamePhase amountsAlbite49.6%Oligoclase30.5%Quartz9.9%Diopside8.8%Muscovite1.2%Fig. 5: Streckeisen diagram for intrusive rocks.Q: quartz, A: alkali-feldspar, P: plagioclase.ReferenceJ.L. Jambor, J.E. Dutrizac, L.A. Groat, M. Raudsepp.Environmental Geology (2002) 43, 1-17.QAPgranitegrano-dioritequartz-richgranodioritequartz-syenitequartz-monzonitequartz-monzo-dioritequartz-dioritetonaliteXRD and XRF are highly complementarymaterials analysis methods which, when usedtogether, greatly improve the accuracy ofphase identification and quantitative analysis.The combination of both methods provides anincrease in the numbers of measured parameters,which means that fewer assumptions are neededfor analysis. This in turn provides not only greateraccuracy of results, but also increases the rangeof samples that can be measured to includesamples about which little or nothing is known inadvance.XRD is the most direct and accurate analyticalmethod for determining the presence andabsolute amounts of mineral species in a sample.Ambiguous results may be obtained however, ifthe sample chemistry and/or origin are unknown.In these cases phase identification can be difficult;in particular, isostructural phases with similarchemical composition will give similar powderdiffraction patterns.In contrast to XRD, XRF provides highly accurateinformation about the elemental compositionof a sample, but it cannot deliver direct phaseinformation. Mass-balance calculations may givesufficient phase information in some cases, butcan also lead to meaningless results e.g. in thepresence of polymorphs.It is the complimentary nature of the XRD andXRFmethods which makes them a valuabletool for quantitative phase analysis in numerousapplications ranging from scientific researchto industrial high-throughput quality control.Particularily in mineralogical and geologicalapplication areas, the combined use of XRD andXRF is booming, offering completely new insightsinto materials and processes. Typical examplesare the cement, minerals & mining, and industrialminerals industries, where the quality of productsand / or efficiency of processes is governed byboth phase and elemental composition. Thecombined use of XRD and XRF methods allowsthe reliable analysis of materials, for which theindividual methods fail to deliver accurate andreliable results.Page 2Quantitative phase and element analysis ofhost/waste rocks and tailings is an importantapplication in the minerals and mining industrywith respect to both process optimization (e.g.acid leaching) and environmental protection:Mining and milling operations are responsiblefor the production of billions of tonnes of wasterock and finely crushed tailings worldwide. Animportant application is the knowledge of therelative amounts of the minerals with acid-producing or neutralization potential for successfulacid-base accounting with respect to both theleaching process as well as acid mine drainage,with its detrimental effects on environment.As an example, we report combined XRD-XRFanalysis of an intrusive rock with unknowncomposition. Of particular interest was itsclassification by mineral content as well asthe detection and accurate quantification ofpotentially present minerals with significant acid-producing or neutralization potential.Powder diffraction data were recorded using aD4 ENDEAVOR powder diffractometer equippedwith a LynxEyeTMdetector (Fig. 1); the totalmeasurement time required was about 5 minutes.For phase identification and quantification,the DIFFRACplussoftware packages EVA,SEARCH and TOPAS were used. StandardlessXRFmeasurements on the same sample wereperformed with the S4 PIONEER and theSPECTRAplussoftware (Fig. 1).Fig. 1: D4 ENDEAVOR diffractometer (right)and S4 PIONEER spectrometer (left) connectedwith conveyer belt. The D4 is equipped withSuper Speed LynxEyeTMdetector.Fig. 2: EVA phase identification results.1) Phase identificationFig. 2 and Tab. 1 show the XRD powder data andthe phase identification results. The major rockforming minerals plagioclase, quartz, diopsideand muscovite are easily and correctly identifiedin a single default run. Note, that the highlysensitive SEARCH algorithm clearly prefers albite(Na-plagioclase) versus anorthite (Ca-plagioclase)as a result of the slightly different latticeparameters of both plagioclase solid solutionend members. Best SEARCH figure-of-meritsobtained for the individual phases were 0.65 and1.48, respectively. Neither ore minerals nor anyK-feldspars or feldspathoids could be detected.Tab. 1: EVA phase identification results.SS-VVV-PPPPCompound Name00-009-0466 (*)Albite00-041-1480 (I)Albite, calcian03-065-0466 (C)Quartz low, syn01-087-0700 (C)Diopside, syn01-089-5402 (C)Muscovite 2M1Page 3Fig. 3: EVA combined XRD-XRF results -comparison of calculated (column "SQD") versusobserved (column "XRF") element concentrations.The difference is given in column "Delta".2) Combined XRD-XRF analysisTo confirm the phase identification results,and to obtain semi-quantitative phase amountestimates consistent with the actual elementalcomposition of the sample, combined XRD-XRFanalysis has been performed with EVA. EVAenables semi-quantitative analysis based on thereference-intensity-ratio (RIR) method using bothXRD as well as XRFdata simultaneously: Onscaling the maximum intensities of the ICDD PDFpatterns to the observed peaks in the powderpattern, EVA calculates both phase and elementconcentrations, and compares the latter with theactually measured element concentrations.Element concentrations as obtained by XRF andused by EVA are provided in Tab. 2. Already atfirst glance, the XRF data fully confirm the absenceof any significant acid-producing ore mineralsdue to the minor concentrations found for heavyelements and the absence of sulphur.Tab. 2: Element concentrations [%] as obtained by XRF.Oxygen47.7Silicon30.0Aluminum 9.75Sodium6.1Calcium3.66Magnesium 0.456Iron1.35Potassium0.271Phosphorus 0.114Chlorine0.0445Titanium0.252Manganese 0.0173Cobalt0.0182Nickel0.0142Strontium0.0595Zirconium0.0143Barium0.0258Wolfram0.101The results for combined XRD-XRF analysis withEVA are shown in Fig. 3 and Tab. 3. The high Navs. Ca concentrations confirm the presence of Na-plagioclase as found by XRD (diopside accountsfor about 60% of the total Ca, as calculatedby EVA). The present Na-plagioclase is mostsuccessfully modelled using two albite phaseswith different Ca amounts. Note the excellentagreement found between the calculated andobserved element concentrations, which is betterthan 1% for all elements, and therefore confirmsthe correctness of the XRD phase identificationresults for all phases.The accuracy of the RIR method is limited byseveral factors such as preferred orientationeffects and the quality of the ICDD PDF data used(e.g. quality of relative intensities, I/Icor values,idealized chemical formula).Tab. 3: EVA semi-quantitative phase analysisresults based on combined XRD-XRF usingreference intensities as given in the ICDD PDFpatterns.SS-VVV-PPPPCompound NamePhaseamounts00-009-0466 (*)Albite58.2%00-041-1480 (I)Albite, calcian15.4%03-065-0466 (C) Quartz low, syn14.0%01-087-0700 (C) Diopside, syn9.9%01-089-5402 (C) Muscovite 2M12.6%The most accurate quantitative results will beobtained from a TOPAS Rietveld refinement. Thecombined XRD-XRF results obtained are of highvalue for defining the refinement model.Page 4BRUKER AXS, INC.5465 EAST ChERYL pARKwAYMADISON, wI 53711-5373USATEL. (+1) (800) 234-XRAYTEL. (+1) (608) 276-3000FAX (+1) (608) 276-3006EMAIL info@bruker-axs.comwww.bruker-axs.comAll configurations and specifications are subject to change without notice. Order No. L88-E00058. © 2006 BRUKER AXS GmbH. Printed in Germany.BRUKER AXS GMBhOESTLIChE RhEINBRUECKENSTR. 49D-76187 KARLSRUhEGERMANYTEL. (+49) (0)(721)595-2888FAX (+49) (0)(721)595-4587EMAIL info@bruker-axs.dewww.bruker-axs.deBRUKER AXS K.K3-9-A, MORIYA, KANAGAwAYOKOhAMA, KANAGAwA 221-0022JApANTEL. (+81) 45 453 1963FAX (+81) 45 440 0757www.bruker-axs.com3) Quantitative TOPAS refinementQuantitative Rietveld analysis has beenperformed using TOPAS, the results are shownin Fig. 4 and Tab. 4. For the final refinementtwo Na-plagioclases with different compositionshave been used to model the data to take theelemental analysis results into account: Albite (0%Ca) and Oligoclase (25% Ca).From the results in Tab. 4 the followingconclusions can be drawn:1. The sample can be unambiguously classified asa quartzdiorite according to Streckeisen, see Fig. 5.2. Combined XRD-XRF analysis and TOPASRietveld refinement can allow a distinction of evenneighboring plagioclase solid solution members(here albite and oligoclase) if present in sufficientamounts.The present sample can be characterised asa rock with insignificant acid producing orneutralisation potential. Remarkable is the easyand reliable determination of the plagioclase typefor estimation of the neutralisation potential. Thisability is of particular interest, as anorthite hasan about 14x higher neutralisation potential thanalbite (e.g. Jambor et al., 2002).Fig. 4: Quantitative TOPAS refinement results.Tab. 4: Quantitative TOPAS refinement results.Compound NamePhase amountsAlbite49.6%Oligoclase30.5%Quartz9.9%Diopside8.8%Muscovite1.2%Fig. 5: Streckeisen diagram for intrusive rocks.Q: quartz, A: alkali-feldspar, P: plagioclase.ReferenceJ.L. Jambor, J.E. Dutrizac, L.A. Groat, M. Raudsepp.Environmental Geology (2002) 43, 1-17.QAPgranitegrano-dioritequartz-richgranodioritequartz-syenitequartz-monzonitequartz-monzo-dioritequartz-dioritetonaliteXRD and XRF are highly complementarymaterials analysis methods which, when usedtogether, greatly improve the accuracy ofphase identification and quantitative analysis.The combination of both methods provides anincrease in the numbers of measured parameters,which means that fewer assumptions are neededfor analysis. This in turn provides not only greateraccuracy of results, but also increases the rangeof samples that can be measured to includesamples about which little or nothing is known inadvance.XRD is the most direct and accurate analyticalmethod for determining the presence andabsolute amounts of mineral species in a sample.Ambiguous results may be obtained however, ifthe sample chemistry and/or origin are unknown.In these cases phase identification can be difficult;in particular, isostructural phases with similarchemical composition will give similar powderdiffraction patterns.In contrast to XRD, XRF provides highly accurateinformation about the elemental compositionof a sample, but it cannot deliver direct phaseinformation. Mass-balance calculations may givesufficient phase information in some cases, butcan also lead to meaningless results e.g. in thepresence of polymorphs.It is the complimentary nature of the XRD andXRFmethods which makes them a valuabletool for quantitative phase analysis in numerousapplications ranging from scientific researchto industrial high-throughput quality control.Particularily in mineralogical and geologicalapplication areas, the combined use of XRD andXRF is booming, offering completely new insightsinto materials and processes. Typical examplesare the cement, minerals & mining, and industrialminerals industries, where the quality of productsand / or efficiency of processes is governed byboth phase and elemental composition. Thecombined use of XRD and XRF methods allowsthe reliable analysis of materials, for which theindividual methods fail to deliver accurate andreliable results.Page 2Quantitative phase and element analysis ofhost/waste rocks and tailings is an importantapplication in the minerals and mining industrywith respect to both process optimization (e.g.acid leaching) and environmental protection:Mining and milling operations are responsiblefor the production of billions of tonnes of wasterock and finely crushed tailings worldwide. Animportant application is the knowledge of therelative amounts of the minerals with acid-producing or neutralization potential for successfulacid-base accounting with respect to both theleaching process as well as acid mine drainage,with its detrimental effects on environment.As an example, we report combined XRD-XRFanalysis of an intrusive rock with unknowncomposition. Of particular interest was itsclassification by mineral content as well asthe detection and accurate quantification ofpotentially present minerals with significant acid-producing or neutralization potential.Powder diffraction data were recorded using aD4 ENDEAVOR powder diffractometer equippedwith a LynxEyeTMdetector (Fig. 1); the totalmeasurement time required was about 5 minutes.For phase identification and quantification,the DIFFRACplussoftware packages EVA,SEARCH and TOPAS were used. StandardlessXRFmeasurements on the same sample wereperformed with the S4 PIONEER and theSPECTRAplussoftware (Fig. 1).Fig. 1: D4 ENDEAVOR diffractometer (right)and S4 PIONEER spectrometer (left) connectedwith conveyer belt. The D4 is equipped withSuper Speed LynxEyeTMdetector.Fig. 2: EVA phase identification results.1) Phase identificationFig. 2 and Tab. 1 show the XRD powder data andthe phase identification results. The major rockforming minerals plagioclase, quartz, diopsideand muscovite are easily and correctly identifiedin a single default run. Note, that the highlysensitive SEARCH algorithm clearly prefers albite(Na-plagioclase) versus anorthite (Ca-plagioclase)as a result of the slightly different latticeparameters of both plagioclase solid solutionend members. Best SEARCH figure-of-meritsobtained for the individual phases were 0.65 and1.48, respectively. Neither ore minerals nor anyK-feldspars or feldspathoids could be detected.Tab. 1: EVA phase identification results.SS-VVV-PPPPCompound Name00-009-0466 (*)Albite00-041-1480 (I)Albite, calcian03-065-0466 (C)Quartz low, syn01-087-0700 (C)Diopside, syn01-089-5402 (C)Muscovite 2M1Page 3Fig. 3: EVA combined XRD-XRF results -comparison of calculated (column "SQD") versusobserved (column "XRF") element concentrations.The difference is given in column "Delta".2) Combined XRD-XRF analysisTo confirm the phase identification results,and to obtain semi-quantitative phase amountestimates consistent with the actual elementalcomposition of the sample, combined XRD-XRFanalysis has been performed with EVA. EVAenables semi-quantitative analysis based on thereference-intensity-ratio (RIR) method using bothXRD as well as XRFdata simultaneously: Onscaling the maximum intensities of the ICDD PDFpatterns to the observed peaks in the powderpattern, EVA calculates both phase and elementconcentrations, and compares the latter with theactually measured element concentrations.Element concentrations as obtained by XRF andused by EVA are provided in Tab. 2. Already atfirst glance, the XRF data fully confirm the absenceof any significant acid-producing ore mineralsdue to the minor concentrations found for heavyelements and the absence of sulphur.Tab. 2: Element concentrations [%] as obtained by XRF.Oxygen47.7Silicon30.0Aluminum 9.75Sodium6.1Calcium3.66Magnesium 0.456Iron1.35Potassium0.271Phosphorus 0.114Chlorine0.0445Titanium0.252Manganese 0.0173Cobalt0.0182Nickel0.0142Strontium0.0595Zirconium0.0143Barium0.0258Wolfram0.101The results for combined XRD-XRF analysis withEVA are shown in Fig. 3 and Tab. 3. The high Navs. Ca concentrations confirm the presence of Na-plagioclase as found by XRD (diopside accountsfor about 60% of the total Ca, as calculatedby EVA). The present Na-plagioclase is mostsuccessfully modelled using two albite phaseswith different Ca amounts. Note the excellentagreement found between the calculated andobserved element concentrations, which is betterthan 1% for all elements, and therefore confirmsthe correctness of the XRD phase identificationresults for all phases.The accuracy of the RIR method is limited byseveral factors such as preferred orientationeffects and the quality of the ICDD PDF data used(e.g. quality of relative intensities, I/Icor values,idealized chemical formula).Tab. 3: EVA semi-quantitative phase analysisresults based on combined XRD-XRF usingreference intensities as given in the ICDD PDFpatterns.SS-VVV-PPPPCompound NamePhaseamounts00-009-0466 (*)Albite58.2%00-041-1480 (I)Albite, calcian15.4%03-065-0466 (C) Quartz low, syn14.0%01-087-0700 (C) Diopside, syn9.9%01-089-5402 (C) Muscovite 2M12.6%The most accurate quantitative results will beobtained from a TOPAS Rietveld refinement. Thecombined XRD-XRF results obtained are of highvalue for defining the refinement model.Page 4BRUKER AXS, INC.5465 EAST ChERYL pARKwAYMADISON, wI 53711-5373USATEL. (+1) (800) 234-XRAYTEL. (+1) (608) 276-3000FAX (+1) (608) 276-3006EMAIL info@bruker-axs.comwww.bruker-axs.comAll configurations and specifications are subject to change without notice. Order No. L88-E00058. © 2006 BRUKER AXS GmbH. Printed in Germany.BRUKER AXS GMBhOESTLIChE RhEINBRUECKENSTR. 49D-76187 KARLSRUhEGERMANYTEL. (+49) (0)(721)595-2888FAX (+49) (0)(721)595-4587EMAIL info@bruker-axs.dewww.bruker-axs.deBRUKER AXS K.K3-9-A, MORIYA, KANAGAwAYOKOhAMA, KANAGAwA 221-0022JApANTEL. (+81) 45 453 1963FAX (+81) 45 440 0757www.bruker-axs.com3) Quantitative TOPAS refinementQuantitative Rietveld analysis has beenperformed using TOPAS, the results are shownin Fig. 4 and Tab. 4. For the final refinementtwo Na-plagioclases with different compositionshave been used to model the data to take theelemental analysis results into account: Albite (0%Ca) and Oligoclase (25% Ca).From the results in Tab. 4 the followingconclusions can be drawn:1. The sample can be unambiguously classified asa quartzdiorite according to Streckeisen, see Fig. 5.2. Combined XRD-XRF analysis and TOPASRietveld refinement can allow a distinction of evenneighboring plagioclase solid solution members(here albite and oligoclase) if present in sufficientamounts.The present sample can be characterised asa rock with insignificant acid producing orneutralisation potential. Remarkable is the easyand reliable determination of the plagioclase typefor estimation of the neutralisation potential. Thisability is of particular interest, as anorthite hasan about 14x higher neutralisation potential thanalbite (e.g. Jambor et al., 2002).Fig. 4: Quantitative TOPAS refinement results.Tab. 4: Quantitative TOPAS refinement results.Compound NamePhase amountsAlbite49.6%Oligoclase30.5%Quartz9.9%Diopside8.8%Muscovite1.2%Fig. 5: Streckeisen diagram for intrusive rocks.Q: quartz, A: alkali-feldspar, P: plagioclase.ReferenceJ.L. Jambor, J.E. Dutrizac, L.A. Groat, M. Raudsepp.Environmental Geology (2002) 43, 1-17.QAPgranitegrano-dioritequartz-richgranodioritequartz-syenitequartz-monzonitequartz-monzo-dioritequartz-dioritetonaliteXRD- provides most direct analytical methol for determining presence and absolute amounts of minerals species in sample. XRD can also identify phasesXRF- provides direct information about chemical composition but cannot deliver direct phase information. Mass-balance calculations can be deducted but may lead to useless results in the presence of a polymorph.
What does magnetic susceptibility indicate about paleoclimate?
Detailed rock magnetic investigations and X-ray diffraction (XRD) were carried out on loess-paleosol sequences of the last interglacial-glacial at Znojmo section in Czech Republic. The results indicate that pedogenesis causes susceptibility enhancement in the paleosols, which is similar to that observed in the Chinese Loess Plateau. κ-T curves, IRM, and XRD show that magnetite is the dominant magnetic mineral in the loess-paleosol sequences at the Znojmo section, while maghemite, hematite, and pyrite/pyrrhotite are minor minerals. Measurements of anisotropy of magnetic susceptibility (AMS) indicate that the magnetic lineation is smaller than the foliation. The susceptibility ellipsoids are oblate and the directions of the maximum principal axes (Κmax) are distributed randomly, and cannot be used to determine the paleo-wind direction. Loess and paleosol sequences in the Czech Republic mainly occur in Bohemia and Moravia. Although geological surveys of these wind-blown sediments can be traced to the 19th century, multiple investigations, such as paleoclimate, pollen and faunal analysis, chronology, and archaeology etc., have recently been carried out to understand the formation and evolution of the aeolian sediments in this area[1 5]. The rock-magnetic properties of aeolian sediments in Czech Republic and their environmental implications are, however, still not well understood, and thus the relationship between aeolian paleo-environmental records in Czech Republic and China is ambiguous. We present here the results of a rock magnetic and XRD study of loess-paleosol sequences at Znojmo (48 51 N, 16 04 E) in Czech Republic. This investigation shows the utility of applying what has been learned from Chinese loess and extracts some of the sedimentary environment and paleoclimate information preserved in these aeolian deposits.
What kind of technology is used in geology?
A huge number of various technologies are used in the geosciences. LiDAR, Radar, Remote Sensing, GIS, X-ray fluorescence spectrometry (XRF), X-ray difraction spectrometry (XRD), material mechanics, flume tables, analog materials, ground penetrating radar, seismic tomography, cosmogenic isotope dataing, Uranium lead dating, stable isotope geochemistry .....
