CN114705830A - Tracing method for concealed granite mass in thick-layer limestone coverage area - Google Patents
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- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/24—Earth materials
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- G—PHYSICS
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- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/26—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring depth
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Abstract
The invention provides a method for tracing concealed granite mass in a thick-layer limestone coverage area, which comprises the following steps: s1, collecting calcite minerals of different types in the coverage area of the thick limestone; s2, carrying out microscopic identification and LA-ICP-MS mineral element and rare earth element analysis on calcite; s3, grinding calcite into powder, and carrying out C-O isotopic composition analysis; s4 according to the mineral element content, the rare earth distribution type and the content delta of calcite13CPDBAnd delta18OSMOWJudging whether the deep part has the magma activity or not by the value; s5, determining the age of deep magma activity accurately through calcite U-Pb; s6, detecting the space shape of the deep rock mass by adopting a wide-area electromagnetic sounding and surface analysis methodState. The method has the advantages of effectively judging whether the activity of the rock pulp rock exists at the deep part of the coverage area of the thick limestone, accurately restricting the time of the invasion of the deep rock pulp rock, effectively reversing the form of the deep high-resistance body and the like.
Description
Technical Field
The invention relates to the field of research on concealed granite masses in thick-layer limestone coverage areas, in particular to a method for tracing concealed granite masses in thick-layer limestone coverage areas.
Background
The most common tracing method for concealed granite in the limestone coverage area at present is a geophysical method or a geochemical tracing method, which is divided into a gravity method and a double-frequency induced polarization method, and the methods all have certain defects: 1) when the distribution range of rock mass is small or the occurrence shape is steep by the gravity method, the generated gravity difference is very small; 2) large-area metal mineralization on the granite contact zone can also generate a comprehensive effect and cannot be accurately identified; 3) in the traditional double-frequency induced polarization method, the limestone is a low-resistance body and the shape is changeable, so the detection depth is limited and the multi-solution exists.
At present, the geochemical tracing method mainly comprises the steps of developing element geochemistry and isotope geochemistry for the rock branches and the dikes on the earth surface to trace deep rock masses or rock bases, and also has some problems: 1) the thick limestone coverage area causes the earth surface and shallow rock veins or rock branches to be lost, and research samples are difficult to obtain; 2) the geochemical tracing method cannot predict the shape, scale and burial depth of the rock mass.
Hydrothermal fluid from deep magma dissolution can migrate along the fault to shallow crystals, where hydrothermal migration is much further than the magma invasion as the fault develops. Calcite, a common gangue mineral, often emerges from the surface in large quantities and is produced in fractures, formations, rock masses and ore bodies in different production states. Calcite in the surface fault is taken as a research object, and whether the deep part of the coverage area has the rock pulp activity or not can be judged through the existing research method, and the era of the deep part rock pulp activity can be accurately determined. And by combining a wide-area electromagnetic sounding technology, the occurrence position and the form of the rock magma at the deep part of the coverage area can be roughly judged.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides a method for tracing concealed granite masses in thick limestone coverage areas.
In order to achieve the above object, an embodiment of the present invention provides a method for tracing concealed granite mass in a thick limestone coverage area, which includes the following steps:
s1, collecting different types of calcite minerals in the thick limestone coverage area;
s2, carrying out microscopic identification and LA-ICP-MS rare earth element analysis on calcite;
s3, grinding calcite into powder, and carrying out C-O isotopic composition analysis;
s4 rare earth distribution type, delta, according to calcite13CPDBAnd delta18OSMOWJudging whether the deep part has the magma activity or not by the value;
s5, determining the years by calcite U-Pb, and accurately determining the age of deep magma activity;
and S6, detecting the spatial form of the deep rock mass by a wide-area electromagnetic sounding and surface analysis method.
Further, the step S1 is specifically: through field work, different types of calcite minerals are collected in a thick limestone coverage area, the different types of calcite are distinguished according to different indexes, and the calcite minerals have the following different types: the color of the calcite is milk white, pink, meat red and black; the particle size is divided into fine particles and coarse particles; the output shape is divided into a pulse shape or a block shape; the output positions are distributed in surrounding rocks, rock masses and ore bodies.
Further, the step S2 is specifically: after a sample is collected, a proper part of the sample is selected for slicing through simple cleaning, the optical sheet can be used for microscopic identification, the symbiotic minerals and the cross-cutting relationship of calcite are mainly observed, and if the cross-cutting relationship exists among different types of calcite, the generation sequence of the calcite is judged according to the cross-cutting relationship; judging whether the current type of calcite is related to mineralization or not by observing the calcite symbiotic minerals; the cut thermometric tablets are used for carrying out LA-ICP-MS rare earth element analysis on calcite; in the laser ablation process, high-purity helium is used as carrier gas and mixed with argon, and then the mixture enters an inductively coupled plasma mass spectrometer to collect an original signal, wherein the flow rate of the high-purity helium is 1.1 liter/minute, and the flow rate of the argon is 13.5 liters/minute; the diameter, frequency and energy of the laser beam spot of the analytical test are respectively 35 μm, 5Hz and 2.0J/cm2The denudation mode is single-point denudation, the analysis time of each point is 90s, and the analysis time comprises 50s blank signals and 40s sample signals; the content of single mineral trace elements of calcite is increased by adopting NIST-610, NIST-612, BHVO-2G and MACS-3And (3) correcting the internal standard of the external standard single, analyzing the calcium content in calcite by using EPMA (Epstein-Barr assay), wherein different types of calcite have different rare earth distribution modes, and the different rare earth distribution modes are used for judging whether the deep part has the activity of the rock pulp.
Further, the step S3 is specifically: the samples were manually filled into 12ml round bottom borosilicate containers and sealed using a butyl rubber septum; penetrating the septum with a two-hole needle at 100 ml/min and automatically flushing the outer container with grade 5 helium; dripping 4-6 drops of phosphoric acid into each external infusion device, placing the external container into an aluminum tray, and keeping the external container at 72 ℃ for 4 hours to calcify the external container; subsequently, a sample was taken through a standard 100 μ L sample loop, and the sample gas was introduced into the mass spectrometer 10 times; separating carbon dioxide from other components by using a gas chromatographic column heated to 70 ℃, and then enabling a peak corresponding to the carbon dioxide to enter a mass spectrometer through shunting; the analysis precision (2 sigma) is better than 0.2 per mill, and the analysis result delta13C is based on PDB, delta18O takes SMOW as a standard, and the conversion relation is as follows: delta18O(V-PDB)＝(δ18O(V-SMOW)30.91)/1.0309, differential C-O isotope projection for different calcites, moderate delta13CPDB(-12 to 3%) low delta18OSMOW(5-8 ‰) can effectively determine whether the activity of the magma is in the deep part of the coverage area of the thick limestone.
Further, the step S4 is specifically: the rare earth partition type and delta of calcite are obtained through experiments13CPDBAnd delta18OSMOWValue, pointing the measured data at delta13C-δ18In the O diagram, the hydrothermal source of calcite is determined according to the different distribution patterns presented.
Further, the step S5 is specifically: after the sample is processed, adhering calcite on a glass slide by two sides under a binocular lens, placing a PVC ring, fully mixing epoxy resin and a curing agent, injecting the mixture into the PVC ring, drying, and stripping a sample target from the glass slide after the resin is fully cured; polishing and polishing a sample target, and then carrying out image analysis under a single polarizer, an orthogonal polarizer and a cathodoluminescence microscope; a proper target area to be tested is defined according to the calcite micrograph, and before testing, the surface of the target area is cleaned by alcohol or absolute ethyl alcohol; the age of deep magma activity can be precisely determined by calcite U-Pb dating annual results.
Distribution pattern and medium delta of low-temperature hydrothermal mineral calcite LREE enriched rare earth elements13CPDB(-12 to 3%) low delta18OSMOW(5-8 per mill) can effectively judge whether the thick limestone coverage area deep part has the magma activity; 2) U-Pb dating technology of hydrothermal calcite can accurately restrict the time of deep magma rock invasion; 3) the wide-area electromagnetic sounding profile and surface analysis technology can effectively invert the deep high-resistance body (apparent resistivity)>7000 Ω. m).
The scheme of the invention has the following beneficial effects:
the geophysical method and the low-temperature hydrothermal mineral geochemistry combined tracing method have the following improvements:
1) by adopting a wide-area electromagnetic sounding technology, the device can effectively penetrate through a limestone covering layer, so that the effective detection deep part reaches 5km underground;
2) the distribution range of low-temperature hydrothermal minerals related to magma hydrothermal is far larger than that of dikes or lithobranches, and particularly in a fault fracture zone, the low-temperature hydrothermal mineral calcite can be transported to the ground surface from the underground 3-5 km along the region fracture;
3) the distribution type of the rare earth elements of the calcite and the composition of C-O isotopes can effectively distinguish the precipitated calcite from the hydrothermal solution precipitated calcite;
4) U-Pb dating technology of calcite restricts the era of deep magma activity.
Drawings
Figure 1 is a schematic representation of different types of calcite of example 1 of the present invention;
FIG. 2a is a graph showing the different mineral content levels for the different types of calcite according to example 1 of the present invention;
FIG. 2b is a graph showing different rare earth partition patterns corresponding to different types of calcite in example 1 of the present invention;
FIG. 3 is a C-O isotope diagram for different types of calcite according to example 1 of the present invention;
FIG. 4 shows the U-Pb perennial calcite of example 1 of the present invention;
FIG. 5 is a distribution diagram of the apparent resistivity of the coverage area of the wide-area electromagnetic inversion profile in example 1 of the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.
Unless defined otherwise, the technical terms used in the present invention have the same meaning as commonly understood by one of ordinary skill in the art. The various raw materials, reagents, instruments, equipment, etc. used in the present invention are commercially available or can be prepared by existing methods.
The collected calcite samples are all from the fault of a copper mountain field in the city of city county of Yongzhou, Hunan province, and four samples are collected, wherein the longitude and latitude coordinates of the collected samples are respectively 111 degrees 30 '5.1' and 25 degrees 17 '22.3'; 111 ° 22'30.1", 25 ° 15' 20.8"; 111 ° 27'15.4", 25 ° 17' 42.8"; 111 ° 29'16.4", 25 ° 17' 30.2".
Aiming at the existing problems, the invention provides a method for tracing the concealed granite mass in the coverage area of thick-layer limestone.
Examples
Tracing method for concealed granite mass in thick-layer limestone coverage area
The method comprises the following specific steps:
s1: by field work, different types of calcite minerals are collected in the thick limestone coverage area, and the different types of calcite are generally roughly distinguished from four aspects of calcite color (milky white, pink, red, black), particle size (fine grains, coarse grains and the like), birth shape (vein shape, lump shape) and output position (in surrounding rocks, rock masses and ore bodies), such as the two different types of calcite shown in fig. 1, wherein one type of calcite is pink, the mineral particles are larger, the other type of calcite is white and the particles are smaller. This example collected calcite primary samples at the mountainous copper field fault (latitude and longitude coordinates: 111 ° 30'5.1", 25 ° 17'22.3") in the city of city way, yongzhou, hanan, hu. Bagging a calcite sample, recording the sample number, and then bringing the calcite sample back to a laboratory for further treatment;
s2: after a calcite sample is collected, a proper part of the sample is selected and sliced through simple cleaning, and the light slice is used for microscopic identification and mainly used for observing the symbiotic minerals of the calcite and the cutting relationship. If the different types of calcite have a through-cutting relationship, the generation sequence of the calcite can be judged according to the through-cutting relationship; and judging whether the current type of calcite is related to mineralization or not by observing the symbiotic minerals of the calcite. The cut thermometric tablets are used for carrying out LA-ICP-MS rare earth element analysis on calcite. In-situ rare earth element analysis is carried out on calcite by using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) of a key laboratory for predicting nonferrous metal mineralization and monitoring geological environment at the university of Zhongnan. A Teledyne Photon machinery analytical HE Excimer 193nm laser ablation system is used in a laboratory, and high-purity helium (1.1 liter/min) is used as a carrier gas in the laser ablation process, mixed with argon (13.5 liters/min) and then enters an inductively coupled plasma mass spectrometer to collect original signals. The diameter, frequency and energy of the laser beam spot of the analytical test are respectively 35 μm, 5Hz and 2.0J/cm2. The ablation mode was single point ablation with an analysis time of 90s for each point, including 50s blank signal and 40s sample signal. In the treatment of the content of the single mineral trace elements of the calcite, NIST-610, NIST-612, BHVO-2G and MACS-3 are adopted to carry out multi-external-standard single-internal-standard correction. The off-line processing of the raw data (including the selection of signal background, the calculation of effective intervals and element content of samples, and the like) is completed by using GLIGHT 4.4.4 developed by GEMOC, and the calcium content in calcite is analyzed by using EPMA;
s3: calcite C-O isotope composition analysis is carried out in a Beijing institute of nuclear industrial geology laboratory. The analytical instruments were a Thermo Finnigan gas bench and a Finnigan 253puls mass spectrometer. Calcite samples were manually filled into 12ml round bottom borosilicate containers and sealed using butyl rubber septa. The septum was penetrated with a two-hole needle at 100 ml/min and the outer container was automatically flushed with grade 5 helium. Thereafter, 4-6 drops of phosphoric acid were added dropwise to each external infusion. The outer container was placed in an aluminum tray and held at 72 ℃ for 4 hours to calcify. Subsequently, a sample is taken through a standard 100 μ L sample loop, which is thenSample gas was introduced into the mass spectrometer 10 times; carbon dioxide was separated from the other components using a gas chromatography column heated to 70 ℃, and the peak corresponding to the carbon dioxide was then split into the mass spectrometer. The analysis precision (2 sigma) is better than 0.2 per mill, and the analysis result delta13C is based on PDB, delta18O takes SMOW as a standard, and the conversion relation is as follows: delta18O(V-PDB)＝(δ18O(V-SMOW)–30.91)/1.0309；
S4: through experiments, the rare earth partition type and delta of calcite can be obtained13CPDBAnd delta18OSMOWThe value is obtained. Experimental results show that the distribution modes of different types of calcite and rare earth are different, and the distribution modes are specifically shown as follows: firstly, the tea is obviously rightly inclined and has no Eu abnormity; ② there is slight right-leaning, there is obvious Eu deficiency; ③ slight right inclination, no Eu anomaly. From La to Lu, the curve changes more smoothly, or the La end is higher than the Lu end; and fourthly, left-leaning type with Eu positive abnormity. The rare earth distribution mode is closely related to hydrothermal sources and magma activities, REE distribution modes in different mineralization stages are obviously different, and the rare earth elements in calcite are gradually reduced from the early stage to the late stage of mineralization, and are changed from LREE enrichment to HREE enrichment. In terms of content, the higher the content of rare earth elements in calcite is, i.e., the more rare earth-rich calcite is considered to be one of the characteristics of hydrothermal rock slurry. Different types of calcite have different rare earth distribution types, the different rare earth distribution modes can judge whether the deep part has the rock pulp activity, the LREE enriched rare earth element distribution type is an index, and the flat rare earth distribution type cannot be used as an index for indicating the deep rock pulp activity; the higher content of the mineral-containing elements means that the mineral-forming potential is larger, and particularly the content difference of Fe and Mn elements is larger. Research has shown that the closer to the ore body, the higher the contents of mineral elements and rare earth elements such as Fe, Mn and the like in calcite, the hydrothermal activity of rock slurry in the deep part can be further explained. As shown in FIG. 2a and FIG. 2b, 4 samples, namely 822-2S7, 822-1S1, 601-12S1 and 530-1S1, are tested in the embodiment, wherein the rare earth partition modes of the two samples, namely 822-2S7 and 822-1S1, are LREE-enriched, namely right-leaning, types; 601-12S1 and 530-1S1, the rare earth partition modes of the two samples are flat, and 822-2S7 and 822-1S1 are respectivelyThe rare earth content is obviously higher than that of the samples 601-12S1 and 530-1S 1. In the aspect of mineral-containing elements, 822-2S7 and 822-1S1 generally have higher mineral-containing element contents than the two samples of 601-12S1 and 530-1S1, especially the two elements of Fe and Mn. The results of the experiments combined show that the two samples 822-2S7 and 822-1S1 reflect the possible presence of plasma activity deep in the sampling region. The C-O isotope composition is widely applied to the tracing research of the source and the evolution of the mineral fluid. There are generally three possible sources of carbon in the mineralized hydrothermal solution: magma-mantle source, sedimentary carbonate rock, organic carbon components in various rocks. Pointing the obtained data at delta13C-δ18In the O diagram, the hydrothermal source of calcite is determined according to the different distribution patterns presented. As shown in FIG. 3, the C-O isotope profiles of the different calcites differ, with a moderate delta13CPDB(-12 to 3%) low delta18OSMOW(5-8 per mill) (circled part in the figure) can effectively judge that the magma rock activity exists in the deep part of the coverage area of the thick limestone; rare earth partition type, mineral element and delta of comprehensive calcite13CPDBAnd delta18OSMOWJudging whether the deep part has the magma activity or not by the value;
s5: at present, a laser ablation system adopted by LA-ICP-MS calcite U-Pb dating is mainly of Resolution S-155 type, and an inductively coupled plasma mass spectrometry (ICP-MS) system has Nu Instruments Attom, Elements and other types; a laser ablation system adopted by LA-MC-ICP-MS calcite U-Pb dating is mainly a New Wave Research 193nm FX ArF excimer laser, and an inductively coupled Plasma mass spectrometry system is mainly of Nu Plasma, Neptune and other models. After the sample is treated, adhering calcite on a glass slide by using two sides under a binocular lens, placing a PVC ring, fully mixing epoxy resin and a curing agent, injecting the mixture into the PVC ring, placing the PVC ring into an oven for drying, and stripping a sample target from the glass slide after the resin is fully cured; polishing and polishing a sample target, and then carrying out image analysis under a single polarizer, an orthogonal polarizer and a cathodoluminescence microscope; and (3) a proper target area to be detected is defined according to the calcite micrograph, and a part with a flat surface, no inclusion or crack and less impurities is preferably selected, so that the influence of common lead is reduced. Before testing, the surface of the test piece is cleaned by alcohol or absolute ethyl alcohol, so that the surface lead pollution is avoided. The age of the deep magma activity can be accurately determined by the age determination result of calcite U-Pb, as shown in FIG. 4, the U-Pb age of a certain calcite standard sample measured by LA-ICP-MS is 254.4 +/-1.7 Ma (2 sigma, MSWD is 5.6, and n is 214), and the obtained calcite age can reflect the age of the deep magma activity;
s6: the distribution state of the apparent resistivity of the coverage area can be revealed through the wide-area electromagnetic inversion profile, so that the spatial form of the deep rock mass is obtained. As in the coverage area study, an abnormally high resistive body (>7000 Ω. m) was found, and the presence of a granite intrusion was confirmed by the drilling data. The granite invasion body form can be clearly reflected by a wide-area electromagnetic inversion section, and the contact zone of the rock mass and the stratum is a favorable position for mineralization, as shown in figure 5.
While the foregoing is directed to the preferred embodiment of the present invention, it will be appreciated by those skilled in the art that various changes and modifications may be made therein without departing from the principles of the invention as set forth in the appended claims.
Claims (6)
1. A method for tracing concealed granite mass in a thick-layer limestone coverage area is characterized by comprising the following steps:
s1, collecting different types of calcite minerals in the thick limestone coverage area;
s2, carrying out microscopic identification and LA-ICP-MS mineral element and rare earth element analysis on calcite;
s3, grinding calcite into powder, and carrying out C-O isotopic composition analysis;
s4 according to the mineral element content, the rare earth distribution type and the content delta of calcite13CPDBAnd delta18OSMOWJudging whether the deep part has the magma activity or not by the value;
s5, determining the years by calcite U-Pb, and accurately determining the age of deep magma activity;
and S6, detecting the spatial form of the deep rock mass by a wide-area electromagnetic sounding and surface analysis method.
2. The method for tracing the blind granite mass covered by the thick limestone as claimed in claim 1, wherein the step S1 is specifically as follows: through field operation, different types of calcite minerals are collected in a thick limestone coverage area, and different types of calcite are distinguished according to different indexes.
3. The method for tracing the blind granite mass covered by the thick limestone as claimed in claim 1, wherein the step S2 is specifically as follows: after a sample is collected, a proper part of the sample is selected for slicing through simple cleaning, the optical sheet can be used for microscopic identification, the symbiotic minerals and the cross-cutting relationship of calcite are mainly observed, and if the cross-cutting relationship exists among different types of calcite, the generation sequence of the calcite is judged according to the cross-cutting relationship; judging whether the current type of calcite is related to mineralization or not by observing the calcite symbiotic minerals; the cut temperature measuring sheet is used for carrying out LA-ICP-MS analysis on ore-containing elements and rare earth elements of the calcite; in the laser ablation process, high-purity helium is used as carrier gas and mixed with argon, and then the mixture enters an inductively coupled plasma mass spectrometer to collect an original signal, wherein the flow rate of the high-purity helium is 1.1 liter/minute, and the flow rate of the argon is 13.5 liters/minute; the diameter, frequency and energy of the laser beam spot of the analytical test are respectively 35 μm, 5Hz and 2.0J/cm2The denudation mode is single-point denudation, the analysis time of each point is 90s, and each point comprises 50s blank signals and 40s sample signals; in the treatment of the single mineral trace element content of the calcite, NIST-610, NIST-612, BHVO-2G and MACS-3 are adopted for multi-external-standard single-internal-standard correction, EPMA is used for analyzing the calcium content in the calcite, the mineral content is high, the possibility that the rock pulp rock exists in a deep part is higher, different types of calcite have different rare earth distribution patterns, different rare earth distribution patterns are used for judging whether the rock pulp activity exists in the deep part, and the LREE enriched type rare earth distribution pattern can be used as an index of the rock pulp activity existing in the deep part.
4. The method for tracing concealed granite mass covered by thick limestone as claimed in claim 1, wherein the method is characterized in thatThe step S3 specifically includes: the samples were manually filled into 12ml round bottom borosilicate containers and sealed using a butyl rubber septum; penetrating the septum with a two-hole needle at 100 ml/min and automatically flushing the outer container with grade 5 helium; dripping 4-6 drops of phosphoric acid into each external infusion device, placing the external container into an aluminum tray, and keeping the external container at 72 ℃ for 4 hours to calcify the external container; subsequently, a sample was taken through a standard 100 μ L sample loop, and the sample gas was introduced into the mass spectrometer 10 times; separating carbon dioxide from other components by using a gas chromatographic column heated to 70 ℃, and then enabling a peak corresponding to the carbon dioxide to enter a mass spectrometer through shunting; the analysis precision (2 sigma) is better than 0.2 per mill, and the analysis result delta13C is based on PDB, delta18O takes SMOW as a standard, and the conversion relation is as follows: delta. for the preparation of a coating18O(V-PDB)＝(δ18O(V-SMOW)30.91)/1.0309, differential C-O isotope projection for different calcites, moderate delta13CPDB(-12 to 3%) low delta18OSMOW(5-8 per mill) can effectively judge the magma activity in the deep part of the coverage area of the thick limestone.
5. The method for tracing the blind granite mass covered by the thick limestone as claimed in claim 1, wherein the step S4 is specifically as follows: the rare earth partition type and delta of calcite are obtained through experiments13CPDBAnd delta18OSMOWValue, pointing the measured data at delta13C-δ18In the O diagram, the hydrothermal source of calcite is determined according to the different distribution patterns presented.
6. The method for tracing the blind granite mass covered by the thick limestone as claimed in claim 1, wherein the step S5 is specifically as follows: after the sample is processed, adhering calcite on a glass slide by two sides under a binocular lens, placing a PVC ring, fully mixing epoxy resin and a curing agent, injecting the mixture into the PVC ring, drying, and stripping a sample target from the glass slide after the resin is fully cured; polishing and polishing a sample target, and then carrying out image analysis under a single polarizer, an orthogonal polarizer and a cathodoluminescence microscope; a proper target area to be tested is defined according to the calcite photomicrograph, and before testing, the surface of the target area is cleaned by alcohol or absolute ethyl alcohol; the age of deep magma activity can be precisely determined by calcite U-Pb dating annual results.
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