Method for determining hydrothermal activity age of volcanic rock reservoir

Abstract

The application discloses a method for determining the hydrothermal activity age of a volcanic rock reservoir, and relates to the technical field of volcanic rock identification. The method comprises the following steps: obtaining a zircon sample target of the volcanic rock reservoir to be measured; performing laser Raman spectrum testing to obtain Raman spectrum data of the zircon sample target; processing the data to obtain the peak position and half-height width of the vibration peak v3SiO4 of the zircon sample target; fitting the half-height width and the position parameter of the wave peak center of the vibration peak v3SiO4 to determine the morphological characteristics and composition of the inclusion in the zircon; performing isotopic proportion and trace element composition analysis to determine the formation age of the zircon; and constructing a half-height width-time fitting curve to determine the formation period of the hydrothermal mineral coexisting with the zircon. The method can be used to divide the zircon period of the volcanic lava, and has a good determination on the zircon genesis, thereby providing an important identification basis for the late hydrothermal / tectonic action events and time of the volcanic rock reservoir.

Description

Technical Field

[0001] This invention relates to the field of volcanic rock identification technology, and in particular to a method for determining the age of hydrothermal activity in volcanic rock reservoirs. Background Technology

[0002] Zircon is the most important accessory mineral in igneous, sedimentary, metamorphic, and lunar rocks, characterized by stable physical and chemical properties, low common lead content, and high closure temperature. Zircon U-Pb dating is the most commonly used method in isotopic geochronology research and is an important tool for constraining the formation of oil and gas reservoirs and addressing subsequent fluid alteration. Zircon U-Pb dating methods mainly include single-grain microthermal ionization mass spectrometry (TIMS), single-grain volcanic lava zircon evaporation method, ion probe mass spectrometry (SHRIMP), laser-induced plasma mass spectrometry (LA-ICP-MS), and (U-Th) / He fission track dating. However, regardless of the method chosen, the ultimate goal is to provide a convincing and reasonable geological interpretation of the obtained U-Pb isotopic age.

[0003] However, volcanic lava reservoirs are susceptible to alteration by complex tectonic fluid processes, resulting in complex zircon genesis within them. Besides major minerals such as albite, quartz, and calcite, volcanic lava reservoirs also contain hydrothermal accessory minerals such as sphene, zircon, apatite, and monazite. These diagenetic minerals are rich in fluid inclusions, including numerous hydrocarbon inclusions of various types (gaseous hydrocarbons, liquid hydrocarbons, methane, bitumen, etc.); simultaneously, numerous associated mineral inclusions are observed within the hydrothermal minerals. Therefore, zircon inclusions can be used to determine the period of hydrothermal activity, thereby precisely pinpointing the timing of later alteration of volcanic lava reservoirs.

[0004] One patent, with publication number CN112748139A and titled "A Method for Determining Zircon Genesis Type Using Zircon Structure," specifically includes: collecting rock and mineral samples; selecting non-magnetic heavy mineral zircon and preparing an analytical sample target; collecting backscattered electron images and cathodoluminescence electron images of the zircon samples; and comparing the collected backscattered electron images and cathodoluminescence electron images of the zircon with typical zircon crystal morphology and internal structural features to determine the zircon genesis type. Another patent, with publication number CN112748175A and titled "A Method for Determining Zircon Genesis Using Trace Element Composition," specifically includes: preparing a zircon sample target; performing in-situ trace element composition analysis on the zircon; and using chondrite-normalized rare earth element distribution curves combined with trace element characteristics to determine the zircon genesis.

[0005] The drawback of the aforementioned existing technologies is that they all analyze the composition of magmatic zircon and hydrothermal zircon to achieve a qualitative analysis of the zircon's origin, but cannot determine the age of hydrothermal activity in later volcanic reservoirs. Summary of the Invention

[0006] Therefore, it is necessary to provide a method for determining the age of hydrothermal activity in volcanic rock reservoirs to address the aforementioned technical problems.

[0007] This invention provides a method for determining the age of hydrothermal activity in volcanic reservoirs, comprising:

[0008] Obtain zircon sample targets from the volcanic rock reservoir to be tested;

[0009] Laser Raman spectroscopy was performed at a fixed point on a zircon sample target using a microconfocal Raman spectrometer to obtain the Raman spectral data of the zircon sample target. The Raman spectral data of the zircon sample target were processed using LabSpec software to obtain the peak position and half-width at half-maximum (WHM) of the vibrational peak ν3SiO4 of the zircon sample target. The position parameters of the WHM and the peak center of the vibrational peak ν3SiO4 were fitted using Lorentz or Gaussian algorithms to determine the morphological characteristics and composition of the inclusions in the zircon.

[0010] Isotope ratios and trace element composition were analyzed at the same location on the zircon sample target using a laser ablation system and inductively coupled plasma mass spectrometry to obtain the time corresponding to the vibration peak ν3SiO4 of the zircon sample target, thereby determining the formation age of the zircon.

[0011] Based on the age of zircon, the composition and morphological characteristics of inclusions within zircon, a half-width-time (WHM) curve is constructed to determine the formation period of hydrothermal minerals associated with zircon.

[0012] Optionally, obtaining zircon from the volcanic rock reservoir to be tested includes: attaching the zircon sample to a target suitable for laser plasma mass spectrometry using double-sided adhesive, fixing it with colorless and transparent epoxy resin, and polishing the surface after curing to form a zircon sample target.

[0013] Optionally, the parameters of the microconfocal Raman spectrometer are set as follows: laser wavelength 532 nm, grating 1800 l / mm, exposure time 10 s, laser energy 10%, and number of accumulations 2.

[0014] Optionally, the zircon half-width at half-maximum (WHM) is corrected when fitting the vibration peak ν3SiO4 and the position parameters of the peak center using the Lorentz or Gaussian algorithm. The calculation formula is as follows:

[0015]

[0016] Where b is the true full width at half maximum (FWHM), bs is the measured FWHM, and s is the Raman resolution.

[0017] Optionally, the peak position and full width at half maximum (FWHM) of the vibrational peak ν3SiO4 include:

[0018] The peak position of the asymmetric tensile Raman peak ν3 is 1007 cm. -1Left and right sides and half height width ≤ 5cm -1 It is a fully crystalline substance;

[0019] The asymmetric tensile Raman peak ν3 is located between 1000 and 980 cm. -1 Between and half-height and width 10-30cm -1 It is metamorphosed zircon;

[0020] Asymmetric stretching Raman peak ν3 position <980cm -1 And half-height and width > 30cm -1 It is a strongly metamorphosed zircon.

[0021] Optionally, the time corresponding to the vibrational peak ν3SiO4 of the zircon sample target is obtained includes:

[0022] Determine whether the zircon age is less than 500 Ma, and determine the correlation between the zircon half-width and U-Pb dating results;

[0023] If the correlation is greater than the correlation threshold, the zircon is considered to have a strong correlation. The formation age of the zircon is determined by using the zircon U-Pb dating results and the half-width regression equation.

[0024] Optionally, the formation age of zircon can be determined using zircon U-Pb dating results and a full width at half maximum (FWHM) fitted regression equation, including:

[0025] t = 19.642e 0.313x

[0026] Where x is the corrected full width at half maximum (FWHM), and t is the fitting time for this sample.

[0027] The method for determining the age of hydrothermal activity in volcanic reservoirs provided in this invention has the following advantages compared to existing technologies:

[0028] The results of this invention, combined with laser Raman spectroscopy measurement and analysis, isotope ratio and trace element composition analysis, can not only be used to classify zircon phases in volcanic lava, but also provide a good determination of zircon genesis, providing important identification basis for the later hydrothermal / tectonic events and timing of volcanic reservoirs.

[0029] In addition, this invention uses the Lorentz or Gaussian algorithm to fit the full width at half maximum (FWHM) and position parameters of the peak center of vibrational peak ν3SiO4, which can determine the composition of inclusions in zircon and thus infer the formation period of this type of zircon. Combined with thin section observation and isotope ratio results, the formation period of a certain mineral can be determined. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating a method for determining the age of hydrothermal activity in a volcanic reservoir, provided in one embodiment.

[0031] Figure 2 A schematic diagram of the peak range of zircon Raman spectroscopy for a method of determining the hydrothermal activity age of a volcanic rock reservoir provided in one embodiment;

[0032] Figure 3 Zircon inclusion Raman characteristic peak image of a method for determining the hydrothermal activity age of a volcanic rock reservoir provided in one embodiment;

[0033] Figure 4 Comparison of zircon ν3 peaks of different origins for a method of determining the hydrothermal activity age of a volcanic rock reservoir provided in one embodiment;

[0034] Figure 5 FWHM-time fitting curve for a method for determining the hydrothermal activity age of a volcanic reservoir provided in one embodiment;

[0035] Figure 6 This is a schematic diagram illustrating the formation period of zircon mineral inclusions in a method for determining the age of hydrothermal activity in a volcanic rock reservoir, provided in one embodiment. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0037] Uranium (U) and thorium (Th) in zircon continuously decay, accumulating and forming phosphorus (Pb). Zircon contains almost no common lead; therefore, the lead in zircon can be attributed to the radioactive decay of U and Th. The daughter nuclei and alpha particles produced by this radioactive decay disrupt the crystal structure of zircon, causing lattice damage. This lattice damage gradually accumulates within the zircon crystal until it undergoes complete metamorphism. Therefore, the lattice damage in zircon can be considered a function of time, and the total amount of lattice damage can be obtained using laser Raman spectroscopy. Some zircons contain inclusions, some of which are small and difficult to detect using CL or a light microscope. Laser Raman spectroscopy allows for in-situ testing to analyze the presence of mineral inclusions at pre-drilled sites. Therefore, laser Raman spectroscopy can be used for preliminary identification and screening of zircons before LA-ICP-MS testing to obtain better zircon dating data.

[0038] Radiation damage affects the vibrational properties of zircon molecules in volcanic lava. As radiation damage increases, the Raman peak shifts to lower wavenumbers, and the full width at half maximum (FWHM) of the Raman peak widens. Laser Raman spectroscopy can measure the radiation damage in volcanic lava zircon. The spontaneous decay of radionuclides releasing alpha particles, along with the alpha particle matrix itself, disrupts the nearby crystal lattice, a phenomenon known as radiation damage (Dα) in volcanic lava zircon. High levels of zircon metacrystallization lead to lattice disruption, making zircon susceptible to hydrothermal fluid alteration and resulting in Pb loss, thus affecting dating results. However, within a certain timeframe, the Raman FWHM of zircon shows a linear relationship with the crystallization time (t). Therefore, the age of untested zircon can be inferred by combining existing zircon dating results with Raman analysis. Raman spectroscopy can identify internal inclusions in zircon without damaging it. However, some zircons contain numerous inclusions, and dating is generally not recommended for these types of zircons. Using the above methods, the formation period of this type of zircon can be inferred, and the formation period of the zircon inclusion minerals can be determined. Combined with thin section observation and U-Pb dating results, the formation period of a certain mineral can be determined.

[0039] In one embodiment, a method for determining the age of hydrothermal activity in a volcanic reservoir is provided, such as... Figure 1 As shown, the method includes:

[0040] Step 1: Sorting the zircons in the volcanic lava, randomly selecting at least 25 zircons to make a zircon sample target.

[0041] Step 2: Perform laser Raman spectroscopy at a fixed point on the zircon sample target using a microconfocal Raman spectrometer to obtain the Raman spectral data of the zircon sample target; process the Raman spectral data of the zircon sample target using LabSpec software to obtain the peak position and half-width at half maximum (FWHM) of the vibrational peak ν3SiO4 of the zircon sample target; use the Lorentz or Gaussian algorithm to fit the FWHM and the position parameters of the peak center of the vibrational peak ν3SiO4 to determine the morphological characteristics and composition of the inclusions in the zircon.

[0042] Step 3: Isotope ratio and trace element composition analysis were performed at the same location on the zircon sample target using a laser ablation system and inductively coupled plasma mass spectrometry to obtain the time corresponding to the vibration peak ν3SiO4 of the zircon sample target, so as to determine the formation age of the zircon.

[0043] Step 4: Determine the formation period of the hydrothermal minerals associated with the zircon based on the zircon's age, the composition of its inclusions, and their morphological characteristics.

[0044] In step 1, zircon samples (≥25) are adhered to a target suitable for laser plasma mass spectrometry using double-sided adhesive, then fixed with colorless and transparent epoxy resin. After curing, the surface is polished to form a zircon sample target.

[0045] In step 2, the composition was determined using a Renishaw inVia-Qontor microconfocal Raman spectrometer. The laser wavelength was 532 nm, the grating was 1800 l / mm, the exposure time was 10 s, the laser energy was 10%, and the number of exposures was 2. Before laser Raman spectroscopy testing of zircon, single-crystal silicon was used for calibration (the Raman peak of single-crystal silicon is 520.7 cm⁻¹). -1 The characteristic peak shift in the Raman spectrum is less than 0.01 cm⁻¹. -1 The experimentally collected zircon Raman characteristic peaks are the peak positions and full width at half maximum (FWHM) of the asymmetric tensile Raman peak ν3.

[0046] Among them, the peak position of the asymmetric tensile Raman peak ν3 is 1007 cm. -1 Left and right sides and half height width ≤ 5cm -1 It is a fully crystalline substance; the asymmetric stretched Raman peak ν3 is located between 1000 and 980 cm⁻¹. -1 Between and half-height and width 10-30cm -1 It is metamorphic zircon; when the asymmetric tensile Raman peak ν3 position is <980cm -1 And half-height and width > 30cm -1 This is a strongly metamorphic zircon. Strongly metamorphic zircons were excluded using the zircon's ν3 peak and full width at half maximum (FWHM). Simultaneously, comparing the Raman characteristics of the same zircon with those of its inclusions allowed for qualitative determination of the inclusion composition using the inclusion characteristic peaks.

[0047] In step 2, the Raman spectral data of the zircon sample target were processed using LabSpec software to obtain the peak position and full width at half maximum (FWHM) value of the vibrational peak ν3SiO4. The FWHM and peak center position parameters of the vibrational peak ν3SiO4 were fitted using the Lorentz or Gaussian algorithm. The zircon FWHM was then corrected using equation (1):

[0048]

[0049] Where b is the true full width at half maximum (FWHM); bs is the measured FWHM; and s is the Raman resolution.

[0050] Highly metamorphosed zircons are excluded by using the full width at half maximum (FWHM) of the zircon sample target. This is because metamorphosed zircons are in a highly disordered state, making Pb easily diffuse and resulting in Pb loss, which affects the accuracy of U-Pb system dating. At the same time, zircons with fewer inclusions are selected for dating, as the elements in the inclusions themselves can affect the accuracy of zircon dating results and trace element content.

[0051] In step 3, the Analyte Excite 193nm gaseous excimer laser ablation system or GeolasPro laser ablation system, in conjunction with inductively coupled plasma mass spectrometry, is used to perform in-situ analysis of the isotopic ratios and elemental composition of U, Th, and Pb on the screened zircons.

[0052] In step 3, zircon is subjected to... 207 Pb / 206 Pb, 207 Pb / 235 U、 206 Pb / 238 U and 208 Pb / 232 Th isotope ratios and 1 sigma calculations of zircon U-Pb crystallization age.

[0053] In step 4, after excluding captured zircons, it is determined whether the zircon age is less than 500 Ma, and the correlation between the zircon half-width and U-Pb dating results is determined. If the correlation is greater than the correlation threshold (0.7), it can be considered that the zircon in the sample has a strong correlation, and the zircon U-Pb dating results and half-width can be used to fit the regression equation. The zircons with more inclusions, which belong to semi-crystalline to crystalline materials but have not been U-Pb dated, are brought into the equation (2) to infer the formation age of the zircons.

[0054] In step 4, the composition and morphological characteristics of the zircon inclusions and the zircon age can be used to determine the formation period of the later hydrothermal minerals in the sample.

[0055] For example, in step one, a zircon sample target is prepared; petrological observations can be performed on the corresponding sample thin sections. In this case, the sample is volcanic lava, which has undergone later hydrothermal alteration. Quartz and calcite are visible in the sample, and the thin section identification results indicate that quartz precipitated earlier than calcite. Accessory minerals such as sphene and apatite are present in the sample.

[0056] Zircon samples (≥25) were attached to a target suitable for laser plasma mass spectrometry using double-sided tape, fixed with colorless and transparent epoxy resin, and after curing, the surface was polished down to the center of the zircon.

[0057] Step 2: Raman spectroscopy analysis of zircon and inclusions;

[0058] The sample target prepared in step one was subjected to compositional analysis using a Renishaw inVia-Qontor microconfocal Raman spectrometer. The laser wavelength was 532 nm, the grating was 1800 l / mm, the exposure time was 10 s, the laser energy was 10%, and the number of exposures was 2. Before laser Raman spectroscopy testing of zircon, single-crystal silicon was used for calibration (single-crystal silicon Raman peak at 520.7 cm⁻¹). -1The characteristic peak shift in the Raman spectrum is less than 0.01 cm⁻¹. -1 Raman spectra of zircon inclusions were tested. The spectral characteristics of zircon are as follows: Figure 2 As shown in the figure. Four types of mineral inclusions were identified in this sample: calcite, quartz, apatite, and pitch. The spectral characteristics of these zircon inclusions are shown in the appendix. Figure 3 .

[0059] Step 3: Perform in-situ trace element composition analysis on zircon.

[0060] For the same sites of zircon obtained from the Raman test in step two, the Analyte Excite 193nm gaseous excimer laser ablation system or the GeolasPro laser ablation system, in conjunction with inductively coupled plasma mass spectrometry, were used to perform in-situ analysis of the isotopic ratios and trace element composition of U, Th and Pb in the zircon.

[0061] The zircon dating results, zircon inclusion Raman spectroscopy results, and zircon Raman spectroscopy results are shown in Table 1.

[0062] Table 1. Zircon dating results, zircon inclusion Raman spectroscopy results, and zircon Raman spectroscopy results.

[0063]

[0064] In step three, the sample contained captured zircon, magmatic zircon, and hydrothermal zircon. CL images showed that these three types of zircon all had similar aspect ratios, similar colors, and oscillating fringes. Raman analysis revealed significant differences in the full width at half maximum (FWHM) of the three types of zircon. This difference is attributed to the different formation periods and cumulative radiation damage of the three types of zircon, and therefore, the FWHM can be used for identification.

[0065] Step four involves determining whether the zircon age is less than 1500 Ma after zircon capture, and assessing the correlation between the zircon's full width at half maximum (FWHM) and U-Pb dating results. If the correlation is greater than 0.7, the zircon in the sample is considered to have a strong correlation, and the zircon U-Pb dating results and the FWHM regression equation can be used. Other zircons with numerous inclusions, belonging to semi-crystalline to crystalline materials but un-dated by U-Pb dating, are then incorporated into this equation to infer the zircon's formation age. The composition and morphological characteristics of the zircon inclusions, along with the zircon age, can be used to determine the formation period of later hydrothermal minerals in the sample.

[0066] The age-FWHM fitted in this experiment was used to perform a regression equation to obtain the age fitting curve for this sample; for some zircons with many inclusions and low degree of metamorphism that have not been dated by U-Pb, their formation age can be estimated.

[0067] The volcanic lava formation age of this sample ranges from 258 to 261 Ma, with the two hydrothermal formation periods occurring at 159.6 ± 1.6 Ma and 24–77 Ma, respectively. Correlation analysis was performed on the full width at half maximum (FWHM), peak position, and dating results of the vibrational peak ν3SiO4, as well as on trace elements in zircon. The results show a strong correlation between FWHM and age, while trace elements and the peak position of the vibrational peak ν3SiO4 have a weaker correlation with zircon. Therefore, this experiment can utilize the zircon dating results and FWHM to fit a regression equation, yielding the following results:

[0068] t = 19.642e 0.313x (R 2 =0.74)-------(Equation 2)

[0069] Where x is the corrected full width at half maximum (FWHM), and t is the fitting time for this sample. The results are shown in Table 2 and... Figure 5 As shown.

[0070] Table 2

[0071]

[0072]

[0073] Mineral inclusion formation time such as Figure 6 As shown, apatite is a common mineral inclusion in zircon, widely distributed in magmatic zircon, captured zircon, and hydrothermal zircon, and cannot be used as a characteristic mineral for determining the genesis of zircon. Quartz is mainly found in zircons from 25 to 175 Ma, calcite in zircons from 65 to 81 Ma, and pitch in zircons from 80 to 161 Ma. It can be considered that quartz formed earlier, and that a larger quantity of quartz was formed hydrothermally, thus capturing more quartz in zircon inclusions. Based on U-Pb dating results, quartz was formed in hydrothermal fluids at 159.6 ± 1.6 Ma. Calcite formed later than quartz, mainly in the second phase of hydrothermal fluids from 24 to 77 Ma, while pitch formed between the two phases of hydrothermal minerals. Therefore, the mineral formation periods in a certain region are quartz-pitch-calcite, which is consistent with thin section observations.

[0074] The trace element composition of zircon varies across different geological bodies due to their formation environments. This zircon inclusion type identification is based on the same geological body (the same analytical sample); zircon inclusions differ between regions. Furthermore, the Raman characteristics of zircon from different lithologies vary, and the fitted curve results should be modified accordingly.

[0075] In summary, the present invention has the following advantages:

[0076] 1. Laser Raman spectroscopy yields faster and lower-cost results compared to (U-Th) / He dating.

[0077] 2. Laser Raman testing of volcanic lava zircon does not damage its structure and composition, and the volcanic lava zircon can be used for other experimental analyses after the test; however, (U-Th) / He dating requires etching of volcanic lava zircon, which will completely destroy the volcanic lava zircon, and no other experiments can be performed afterward.

[0078] 3. The results of combined laser Raman spectroscopy measurement and analysis, isotope ratio and trace element composition analysis can not only be used to classify the zircon phases in volcanic lava, but also have a good determination of zircon genesis, providing important identification basis for the later hydrothermal / tectonic events and timing of volcanic reservoirs.

[0079] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for determining the age of hydrothermal activity in volcanic rock reservoirs, characterized in that, include: Obtain zircon sample targets from the volcanic rock reservoir to be tested; Laser Raman spectroscopy was performed at a fixed point on a zircon sample target using a microconfocal Raman spectrometer to obtain the Raman spectral data of the zircon sample target. The Raman spectral data of the zircon sample target were processed using LabSpec software to obtain the peak position and half-width at half-maximum (WHM) of the vibrational peak ν3SiO4 of the zircon sample target. The position parameters of the WHM and the peak center of the vibrational peak ν3SiO4 were fitted using Lorentz or Gaussian algorithms to determine the morphological characteristics and composition of the inclusions in the zircon. Isotope ratios and trace element composition were analyzed at the same location on the zircon sample target using a laser ablation system and inductively coupled plasma mass spectrometry to obtain the time corresponding to the vibration peak ν3SiO4 of the zircon sample target, thereby determining the formation age of the zircon. The time corresponding to the vibrational peak ν3SiO4 of the zircon sample target is obtained includes: Determine if the zircon age is less than 500 Ma, and assess the correlation between the zircon half-width at half-maximum (HWHM) and U-Pb dating results. If the correlation is greater than the correlation threshold, the zircon is considered to have a strong correlation. The zircon formation age is then determined using the zircon U-Pb dating results and the HWHM fitted regression equation. Based on the age of zircon, the composition and morphological characteristics of inclusions within zircon, a half-width-time (WHM) curve is constructed to determine the formation period of hydrothermal minerals associated with zircon.

2. The method for determining the age of hydrothermal activity in a volcanic reservoir as described in claim 1, characterized in that, The process of obtaining zircon from the volcanic rock reservoir to be tested includes: attaching the zircon sample to a target suitable for laser plasma mass spectrometry using double-sided adhesive, fixing it with colorless and transparent epoxy resin, and polishing the surface after curing to form a zircon sample target.

3. The method for determining the age of hydrothermal activity in a volcanic reservoir as described in claim 1, characterized in that, The parameters of the microconfocal Raman spectrometer are set as follows: laser wavelength 532nm, grating 1800l / mm, exposure time 10s, laser energy 10%, and cumulative exposure times 2.

4. The method for determining the age of hydrothermal activity in a volcanic reservoir as described in claim 1, characterized in that, When correcting the zircon half-width at half-maximum (WHM) and the position parameters of the peak center of vibration ν3SiO4 using the Lorentz or Gaussian algorithm, the formula is as follows: Where b is the true half-width and height, b s This is the actual measured half-height and width. s This is the Raman resolution.

5. The method for determining the age of hydrothermal activity in a volcanic reservoir as described in claim 1, characterized in that, The peak position and full width at half maximum (FWHM) of the vibration peak ν3SiO4 include: The peak position of the asymmetric stretched Raman peak ν3 is 1007 cm. -1 Left and right sides and half height and width ≤ 5 cm -1 It is a fully crystalline substance; The asymmetric tensile Raman peak ν3 is located between 1000 and 980 cm. -1 Between and half-height and width 10-30 cm -1 It is metamorphosed zircon; Asymmetric stretched Raman peak ν3 position <980 cm -1 And half-height and width > 30cm -1 It is a strongly metamorphosed zircon.

6. The method for determining the age of hydrothermal activity in a volcanic reservoir as described in claim 1, characterized in that, The determination of zircon formation age using zircon U-Pb dating results and a full width at half maximum (FWHM) fitting regression equation includes: t=19.642e 0.313x Where x is the corrected full width at half maximum (FWHM), and t is the fitting time for this sample.

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