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Article

Experimental Analysis of Elastic Property Variations in Methane Hydrate-Bearing Sediments with Different Porosities

by
Weiping Xu
1,2,*,
Bangrang Di
1,2,
Haifeng Chen
3 and
Jianxin Wei
1,2
1
State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China
2
CNPC Key Laboratory of Geophysical Exploration, China University of Petroleum (Beijing), Beijing 102249, China
3
Bureau of Geophysical Prospecting Inc., China National Petroleum Corporation, Zhuozhou 072751, China
*
Author to whom correspondence should be addressed.
J. Mar. Sci. Eng. 2024, 12(12), 2370; https://doi.org/10.3390/jmse12122370
Submission received: 13 November 2024 / Revised: 18 December 2024 / Accepted: 19 December 2024 / Published: 23 December 2024
(This article belongs to the Section Marine Energy)
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Abstract

Natural gas hydrates, a promising clean energy resource, hold substantial potential. Porosity plays a crucial role in hydrate systems by influencing formation processes and physical properties. To clarify the effects of porosity on hydrate elasticity, we examined methane hydrate formation and its acoustic characteristics. Experiments were conducted on sediment samples with porosities of 23%, 32%, and 37%. P- and S-wave velocities were measured to assess acoustic responses. Results show that as hydrate saturation increases, sample acoustic velocity also rises. However, high-porosity samples consistently exhibit lower acoustic velocities compared to low-porosity samples and reach a lower maximum hydrate saturation. This behavior is attributed to rapid pore filling in high-porosity samples, which blocks flow pathways and limits further hydrate formation. In contrast, hydrate formation in low-porosity sediments progresses more gradually, maintaining clearer pore channels and resulting in relatively higher hydrate saturation. Higher porosity also accelerates the shift of hydrates from cementing to load-bearing morphologies. These findings underscore porosity’s significant influence on hydrate formation and provide insights into observed variations in hydrate saturation and acoustic velocity across different experimental conditions.

1. Introduction

Marine gas hydrates are widely distributed in marine sediments and are recognized as both a critical energy resource and a potential factor in climate dynamics [1,2]. Their significance has made a central focus of marine geoscience research [3]. Hydrates are ice-like clathrate compounds formed when methane gas combines with water molecules under high-pressure and low-temperature conditions [4,5]. The critical role of porosity in gas hydrate systems has been widely recognized [6,7,8,9,10]. High-porosity sediments exhibit lower capillary pressures, enhancing gas diffusion and accelerating hydrate formation [11,12,13]. In contrast, low-porosity sediments restrict gas diffusion rates [14,15,16], thereby slowing hydrate formation. Porosity not only affects the rate of hydrate formation but also directly influences the hydrate content within the formation [17], making it a key factor in production forecasting and recovery analysis [18,19]. Consequently, investigating the impact of porosity on hydrate systems is essential, particularly in cases where hydrate formation may lead to sediment pore blockage, impeding fluid flow within the reservoir [17].
Seismic exploration is a primary approach in gas hydrate research, efficiently estimating hydrate distribution and saturation through acoustic velocity analysis and seismic imaging [20,21]. However, the potential impact of porosity on the acoustic properties of hydrates remains insufficiently studied. Changes in porosity can significantly alter sediment structure and flow channels [22,23,24], subsequently affecting the elastic properties during hydrate formation [25]. Additionally, as sediment depth increases, porosity generally decreases [26,27,28], which further influences hydrate formation mechanisms and acoustic responses across varying porosity conditions.
Significant variability exists in the relationship between hydrate saturation and acoustic velocity across experiments. For instance, some studies report a convex trend between hydrate saturation and acoustic velocity [29,30,31], while others have observed a concave trend [32,33,34]. This discrepancy is often closely linked to hydrate morphology [32,35,36,37,38]. Hydrates typically occur in sediments as cementing, pore-filling, or load-bearing types [32,39]. Cementing hydrates form between grain contact points, enhancing sediment stiffness; pore-filling hydrates occupy the spaces between grains, while load-bearing hydrates reinforce the sediment framework [39,40]. At low saturation, cementing hydrates can significantly enhance acoustic velocity [29,36,41], whereas pore-filling and load-bearing hydrates exhibit comparatively limited increases in acoustic velocity under low saturation conditions [32,39]. Hydrate morphology directly influences the elastic properties of sediments, significantly impacting the accurate estimation of hydrate saturation [42]. Porosity likely plays a critical role in driving these morphological changes. Therefore, further investigation into the effects of porosity on hydrate morphology and acoustic characteristics is essential. Such research will help reconcile experimental inconsistencies and enhance future in situ evaluations of hydrate reservoirs.
This study developed a gas hydrate experimental simulation system to investigate hydrate formation under varying porosity conditions. The analysis systematically examined changes in P- and S-wave velocities across three different sample groups. Coupled with rock physics modeling, the investigation further explores the influence of porosity on hydrate morphology and the physical properties of sediments. The findings provide insight into the mechanisms by which porosity affects hydrate morphology and pore-blocking phenomena. These findings reveal the critical role of porosity in the formation dynamics and acoustic responses of gas hydrate-bearing sediments within marine environments, offering implications for improved understanding and evaluation of hydrate reservoirs.

2. Methods

2.1. Experiment Setup

The experimental system comprises three primary modules: pressure control, hydrate formation, and ultrasonic testing (Figure 1). The pressure control module includes a methane cylinder for gas supply, pore and confining pressure booster pumps for precise pressure control, and pressure transducers for continuous monitoring. The hydrate formation module includes a high-pressure hydrate reactor and a thermostatic chamber simulating the specific pressure and temperature conditions required for methane hydrate formation. The thermostatic chamber controls temperature fluctuations, while the reactor withstands high pressures necessary for hydrate synthesis. This ultrasonic testing system records the real-time transmission properties of P- and S-waves during hydrate formation using multi-channel selectors, pulse transmitters, oscilloscopes, and a computer for data analysis. Waveform changes are captured and analyzed to assess acoustic velocity and attenuation.

2.2. Experiment Approach

In this study, hydrate formation experiments were conducted on three groups of sediment samples with varying porosities to examine the effects of porosity on hydrate formation and ultrasonic velocity. The experimental procedure followed these steps (Figure 2):
(1) Sample preparation: Based on statistical analysis of the SH2 well in the Shenhu area of the South China Sea, samples were prepared with identical mineral compositions (28% quartz, 20% clay, 14% calcite, 12% feldspar, and 26% mica) [43].To ensure homogeneity, these minerals were mixed for 24 h in a ball mill, following a procedure similar to that described by Ding et al. (2017) [44]. The mixture was then combined with epoxy resin for 1 h. Porosity was controlled by adjusting compaction pressure: lower pressure for high-porosity samples and higher pressure for low-porosity samples. After compaction, core specimens (38 mm diameter, 63 mm height) were cut, and porosity was measured using the water saturation method. Detailed parameters are listed in Table 1;
(2) Experimental Setup: The hydrate formation apparatus was purged with gas to minimize contaminants. Pre-saturated samples (90% water) were placed in the hydrate reactor under a confining pressure of 10 MPa to simulate in situ conditions. The temperature was set to 4 °C, typical of gas hydrate deposits. Methane gas was pre-injected into a cooling cylinder, gradually cooled in the thermostatic chamber, and then introduced into the hydrate reactor. Under high-pressure and low-temperature conditions, methane dissolved into water, forming a supersaturated solution and initiating hydrate nucleation. As methane and water molecules interacted, a stable cage-like hydrate structure formed;
(3) Ultrasonic Monitoring: A real-time ultrasonic system measured P- and S-wave velocities during hydrate formation. Transducers at opposite ends of the sample captured waveform changes, allowing analysis of hydrate saturation effects on ultrasonic velocities;
(4) Porosity Impact Analysis: To examine the influence of porosity, steps in (2) were repeated with samples of varying porosity. The collected data were subsequently analyzed using rock physics models to further understand porosity’s effect on hydrate elastic property.

2.3. Calculation of Hydrate Saturation

In this study, hydrate saturation was calculated using the real gas equation [45]. Pressure data were recorded every 0.5 min until the hydrate formation process was complete, providing a detailed profile of hydrate state changes. The experimental temperature was maintained consistently at 4 °C to eliminate any potential impact of temperature fluctuations on the results.
The hydrate saturation S h can be expressed as
S h = V h V p o r e = m h ρ h V p o r e ,
where m h represents the mass of methane hydrate; ρ h is the density of the methane hydrate; V h represents the hydrate volume; V p o r e represents the pore volume;
The m h can be calculated as follows:
m h = Δ n M h = ( n 1 − n 2 ) M h ,
where Δ n represent the number of moles of methane. n 1 and n 2 represents the number of moles of methane before and after hydrate formation, respectively. M h represents the molar mass of the methane hydrate.
The n 1 and n 2 can be calculated as the nonideal gas law [45]:
n 1 = P 1 V f r e e Z 1 R T ,
n 2 = P 2 V f r e e Z 2 R T ,
where P 1 and P 2 are the pore pressures in the reactor before and after hydrate formation, respectively; V f r e e is the free space of the methane; Z 1 and Z 2 are the compressibility factor of methane gas before and after hydrate formation, respectively [46]; R represents the molar gas constant (8.314 J/mol/K); and T represents the experimental temperature.
By combining Equations (1)–(4), we can derive the hydrate saturation S h as follows:
S h = n 1 − n 2 M h ρ h V p o r e = P 1 Z 1 − P 2 Z 2 V f r e e M h R T ρ h V p o r e .

3. Results

Figure 3a shows the changes in injection pressure and back pressure with experimental time. During the initial phase (0–50 min), the injection and back pressures remained nearly identical, indicating balanced pressure conditions and uniform gas diffusion. However, after 50 min, a pressure differential between the injection and back pressures. The rate of pressure decreases for the injection pressure slowed considerably, while the back pressure continued to decline. This suggests that, as hydrate formation progressed, the gas permeability paths began to narrow. This change was likely due to hydrate accumulation of hydrate within the pore channels, which increasingly restricted gas flow. The observed increase in pressure differential indicates the initiation of localized clogging effects caused by hydrate formation within the sediment matrix.
Figure 3b,c show the changes in P-wave and S-wave waveforms with experiment time. As the experiment progressed, the first arrival times of both waves gradually decreased, indicating an increase in wave propagation velocity within the sample. This velocity increase suggests that hydrate formation significantly enhanced the sample’s structural integrity. Additionally, the amplitudes of both P- and S-waves increased over time. This implies that hydrate formation strengthened the internal structure of the sample, thereby improving energy transmission efficiency.
The experimental results in Figure 4a,b demonstrates a clear inverse relationship between porosity and acoustic wave velocity in hydrate-bearing sediment samples. Samples with higher porosity exhibited lower P- and S-wave velocities across various hydrate saturation levels. This phenomenon can be attributed to the reduced contact points between solid grains in higher-porosity samples, weakening the solid framework and thereby decreasing acoustic velocity. Unlike P-waves, which are sensitive to both the solid matrix and pore fluids, S-waves primarily propagate through the solid framework, rendering them less affected by fluid presence. The observed increase in S-wave velocity with hydrate saturation indicates that hydrates primarily form as a solid phase within pore structures, reinforcing the grain framework and enhancing the shear stiffness of the sediment. Notably, as porosity increases, the achievable maximum hydrate saturation decreases.
The observed difference in the trends of P- and S-wave velocities at 37% porosity may be attributed to changes in fluid distribution during hydrate formation. As water transforms into hydrate, water saturation decreases. This decrease in saturation causes a significant initial reduction in P-wave velocity due to fluid effects, followed by a gradual increase [47,48]. In contrast, S-wave velocity is less influenced by fluid presence. During the initial stage of hydrate formation, the shear stiffness rapidly increases, leading to a faster rise in S-wave velocity. As hydrate saturation increases, the trend of S-wave velocity gradually stabilizes. Hydrate formation enhances both P- and S-wave velocities. Therefore, at lower hydrate saturations, the increase in P-wave velocity is slower than that of S-wave velocity. As saturation increases, the rate of increase in P-wave velocity surpasses that of S-wave velocity. At lower porosities, the effect of water saturation on P-wave velocity diminishes [48], leading to a smaller difference between the trends of P- and S-wave velocities.

4. Discussion

To analyze hydrate morphologies at varying saturation, experimental data were compared with the simplified three-phase Biot-type equation (STPBE) [49,50] and the cementing model [51]. As shown in Figure 5, during the low saturation phase (0–10%), P-wave velocity exhibits a rapid increase. This pattern aligns closely with the predictions of the cementation model commonly applied in rock physics. This finding suggests that hydrates predominantly exist in a cementing morphology at grain contact points. This morphology effectively enhances the overall stiffness of the sediment, which is consistent with previous studies [36]. Additionally, scanning electron microscope (SEM) images in Figure 6 reveal several pore contact points where cementing hydrates may form.
When the hydrate saturation reached 10–33%, the experimental results aligned with the predictions of STPBE, with parameters ε = 0 and α = 10.5. Within this range, the STPBE indicates that hydrates progressively adopt a load-bearing morphology. This transition suggests that, at these saturation levels, hydrates extend beyond strengthening grain contact points. Instead, they gradually occupy pore spaces, forming a stable support framework that enhances the overall strength of the sediment structure.
Figure 7 shows the pressure changes during four stages of the hydrate formation experiment, along with corresponding schematic diagrams of microscopic distributions. Gas Injection Phase (0–10 min): During this initial phase, methane gas was injected into the sample through the injection port, leading to a gradual increase in pore pressure as the gas diffused into the pore space. At this point, the porous structure remained relatively open, allowing the gas to flow freely and distribute. Gas Equilibrium Phase (10–85 min): After the gas injection valve was closed, no further gas entered the system, and the internal pore pressure stabilized. During this phase, methane gradually dissolved into the pore water. This dissolution allowed gas molecules to interact with water, initiating the formation of hydrate nuclei [52,53]. Rapid Hydrate Growth Phase (85–385 min): During this phase, the hydrate formation rate significantly increased, primarily generating cementing-type hydrate structures at grain contact points. These cementing hydrates enhanced the rigidity of the pore structure by binding grains together. As hydrate formation progressed, the permeability of pore channels decreased. This reduction progressively restricted gas flow, leading to a differential between injection and back pressures. With increasing hydrate content, the morphology gradually transitions to a load-bearing type. The transition reinforced the sediment framework, further reducing channel permeability. It also increased resistance to gas flow. Stable Hydrate Phase (385–480 min): This final stage represents the completion of the hydrate formation process. By this time, hydrates had extensively filled the sample’s pore space, predominantly adopting a load-bearing morphology. The sediment pore structure was now densely packed with hydrates, almost completely blocking gas flow. The differential between injection and back pressures reached a maximum, indicating that pore channels were almost completely blocked by the hydrate.
Based on Figure 4 and Figure 7, in high porosity samples, larger and more abundant pore spaces provide effective pathways for gas diffusion. This high diffusion rate offers adequate surface area for adhesion and nucleation, thereby accelerating the initial growth of hydrates. However, rapid hydrate accumulation quickly fills the pore spaces, blocking these diffusion pathways. The blockage restricts further gas movement and ultimately limits continuous hydrate formation. Consequently, hydrate saturation in high-porosity samples becomes constrained as pore spaces progressively clog. In contrast, low-porosity samples exhibit a denser pore structure, which slows the hydrate formation process. This gradual growth allows hydrates to accumulate more persistently and continuously, eventually achieving higher saturation.
The transition from cementing to load-bearing type in hydrate formation is also influenced by porosity. In samples with 23% porosity, hydrates transition from cementing to load-bearing morphologies at approximately 0.15 saturation. By comparison, in samples with 37% porosity, this transition occurs at a much lower saturation (approximately 0.025). This indicates that in high-porosity samples, fewer contact points exist between sediment grains, leading to reduced cementing hydrate formation. Therefore, it can be inferred that with further increases in porosity, the sediment matrix may lack any cementing hydrate morphology. In such cases, hydrates would exist exclusively in a load-bearing type. This phenomenon also explains variations in hydrate saturation and P-wave velocity trends observed in different experiments.
Seismic exploration is a common method for studying hydrate formations, with the bottom simulating reflector (BSR) serving as a key indicator for identifying hydrates [54,55]. However, due to variations in subsurface conditions, BSR-based interpretations can sometimes lack clarity [56]. Figure 8 shows the seismic model developed to investigate the influence of porosity on BSR characteristics, integrating experimental data. The water-bearing formation data were obtained from experimental results on a 37% porosity sample without gas injection. The gas-water layer data were obtained from experimental results on a 23% porosity sample during the second stage of the experiment.
To control the variable as porosity, the hydrate saturation range for all three layers was set between 0–16%. The variation of saturation with formation distance is shown in Figure 9a. The increase in saturation affects the response characteristics of P- and S-waves. Figure 9b,c show the synthetic seismic data of P- and S-wave waveforms.
Due to variations in porosity within the hydrate layers, multiple BSR reflections appear in the forward-modeled data. This observation aligns with real seismic data, where multiple BSR reflections are commonly observed [58,59]. Greater porosity differences among hydrate layers lead to stronger acoustic impedance contrasts with adjacent layers, thereby enhancing BSR characteristics in the seismic profile. This study highlights how porosity-induced variations within marine hydrate-bearing sediment layers improve seismic detectability, offering valuable insights into the characterization of natural gas hydrate reservoirs. This study primarily focuses on the influence of porosity. However, other geological factors, such as pore structure and fractures, may also impact hydrate-bearing formations in actual subsurface conditions. Further research is needed to explore these complexities.

5. Conclusions

This study systematically investigates the impact of porosity on methane hydrate formation and its acoustic characteristics. Experiments on methane hydrate formation were conducted using sediment samples with three distinct porosities. P- and S-wave velocity measurements were also taken, revealing the critical role of porosity in hydrate formation and stability:
(1) With increasing hydrate saturation, the acoustic velocity of the samples consistently increases. However, the acoustic velocities in high-porosity samples remain significantly lower than those in low-porosity samples across all saturation levels;
(2) In low-saturation samples, the hydrate morphology initially exhibits a cementing type, transitioning to a load-bearing type as saturation increases;
(3) The maximum achievable saturation in high-porosity samples is lower than in low-porosity samples. This is primarily due to rapid filling and clogging of pore spaces in high-porosity sediments, limiting further hydrate formation;
(4) Higher porosity accelerates the transition from cementing to load-bearing hydrate morphologies. In high-porosity samples, fewer grain contact points reduce the potential of cementing hydrates, resulting in a preference for load-bearing morphology;
(5) The critical saturation at which this morphology transition occurs varies with porosity. For example, samples with 23% porosity transition at around 0.15 saturation, while samples with 37% porosity transition at approximately 0.025 saturation.
These findings provide new insights into the inconsistencies observed in hydrate saturation and acoustic velocity trends across different experiments. It highlights the significant influence of porosity on the acoustic response of hydrate-bearing sediments. Notably, the inference of hydrate morphology in this study is based on experimental data and rock physics models, which may not fully capture the complexity of hydrate morphology distribution within pores. Future studies could integrate X-ray computed tomography (CT) imaging for a more accurate analysis of the porosity-hydrate relationship.

Author Contributions

Conceptualization, W.X.; methodology, W.X. and J.W.; software, W.X.; validation, W.X. and B.D.; formal analysis, B.D. and H.C.; investigation, W.X. and J.W.; resources, H.C.; data curation, W.X. and J.W.; writing—original draft preparation, W.X.; writing—review and editing, B.D., and H.C.; visualization, W.X.; supervision, B.D.; project administration, H.C.; funding acquisition, B.D. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the research project of the China National Petroleum Corporation (grant 2021DJ3503).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data associated with this research are available and can be obtained by contacting the corresponding authors.

Conflicts of Interest

Haifeng Chen is employed at Bureau of Geophysical Prospecting Inc., China National Petroleum Corporation. The other authors declare no conflicts of interest.

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Figure 1. Schematic of the hydrate formation experimental system, showing key components for pressure control, hydrate formation, and ultrasonic testing.
Figure 1. Schematic of the hydrate formation experimental system, showing key components for pressure control, hydrate formation, and ultrasonic testing.
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Figure 2. Experimental procedure flowchart for methane hydrate formation, illustrating sample preparation, core cutting, sample loading into the experimental setup (with confining pressure indicated by orange arrows), and hydrate formation (represented by yellow areas within the pore space). The black ellipses represent the sample framework.
Figure 2. Experimental procedure flowchart for methane hydrate formation, illustrating sample preparation, core cutting, sample loading into the experimental setup (with confining pressure indicated by orange arrows), and hydrate formation (represented by yellow areas within the pore space). The black ellipses represent the sample framework.
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Figure 3. Experimental data changes with time for the sample with 23% porosity: (a) pore pressure, (b) P-wave waveforms, and (c) S-wave waveforms, where the red lines indicate the P- and S-wave first arrival times, respectively.
Figure 3. Experimental data changes with time for the sample with 23% porosity: (a) pore pressure, (b) P-wave waveforms, and (c) S-wave waveforms, where the red lines indicate the P- and S-wave first arrival times, respectively.
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Figure 4. Changes in elastic wave velocities (a) Vp and (b) Vs. with hydrate saturation in hydrate-bearing sediments.
Figure 4. Changes in elastic wave velocities (a) Vp and (b) Vs. with hydrate saturation in hydrate-bearing sediments.
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Figure 5. Comparison of experimental data for a 32% porosity sample with theoretical models. The STPBE includes two adjustable parameters, ε and α, which characterize hydrate distribution and sediment stiffening. When ε = 0, the hydrate exhibits a load-bearing morphology; when ε = 1, it indicates a pore-filling morphology. Values of 0 < ε < 1 suggest a coexistence of both load-bearing and pore-filling hydrate morphologies. The top-left illustration represents cementing-type hydrate, while the right illustration represents load-bearing hydrate.
Figure 5. Comparison of experimental data for a 32% porosity sample with theoretical models. The STPBE includes two adjustable parameters, ε and α, which characterize hydrate distribution and sediment stiffening. When ε = 0, the hydrate exhibits a load-bearing morphology; when ε = 1, it indicates a pore-filling morphology. Values of 0 < ε < 1 suggest a coexistence of both load-bearing and pore-filling hydrate morphologies. The top-left illustration represents cementing-type hydrate, while the right illustration represents load-bearing hydrate.
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Figure 6. SEM image of sediment sample, showing pore contact points with yellow arrows indicating areas where cementing hydrates may form between grain contacts.
Figure 6. SEM image of sediment sample, showing pore contact points with yellow arrows indicating areas where cementing hydrates may form between grain contacts.
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Figure 7. Relationship between microscopic hydrate distribution and pressure changes during the four phases of hydrate formation: (I) Gas injection; (II) Gas equilibrium; (III) Rapid hydrate growth; (IV) Stable hydrate.
Figure 7. Relationship between microscopic hydrate distribution and pressure changes during the four phases of hydrate formation: (I) Gas injection; (II) Gas equilibrium; (III) Rapid hydrate growth; (IV) Stable hydrate.
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Figure 8. Geological model of gas hydrate-bearing sediment. The geological model consists of five layers: a water-bearing layer, three hydrate reservoirs with different porosities (37%, 32%, and 23%), and a gas-water layer.
Figure 8. Geological model of gas hydrate-bearing sediment. The geological model consists of five layers: a water-bearing layer, three hydrate reservoirs with different porosities (37%, 32%, and 23%), and a gas-water layer.
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Figure 9. Synthetic modeling data showing (a) hydrate saturation, (b) P-wave waveform, and (c) S-wave waveform changes with lateral distance. The Aki-Richard approximation equation [57] was used for the seismic forward modeling with a 40 Hz Ricker wavelet.
Figure 9. Synthetic modeling data showing (a) hydrate saturation, (b) P-wave waveform, and (c) S-wave waveform changes with lateral distance. The Aki-Richard approximation equation [57] was used for the seismic forward modeling with a 40 Hz Ricker wavelet.
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Table 1. Physics parameter of samples at 0.1013 MPa (atmospheric pressure) and 20 °C, including porosity, acoustic velocity, and other relevant parameters.
Table 1. Physics parameter of samples at 0.1013 MPa (atmospheric pressure) and 20 °C, including porosity, acoustic velocity, and other relevant parameters.
PorosityDensity (g/cm3)Diameter (mm)Height (mm)Vp (m/s)Vs (m/s)
23%1.8638.262.926671686
32%1.6437.862.716341030
37%1.5338.062.41556976
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MDPI and ACS Style

Xu, W.; Di, B.; Chen, H.; Wei, J. Experimental Analysis of Elastic Property Variations in Methane Hydrate-Bearing Sediments with Different Porosities. J. Mar. Sci. Eng. 2024, 12, 2370. https://doi.org/10.3390/jmse12122370

AMA Style

Xu W, Di B, Chen H, Wei J. Experimental Analysis of Elastic Property Variations in Methane Hydrate-Bearing Sediments with Different Porosities. Journal of Marine Science and Engineering. 2024; 12(12):2370. https://doi.org/10.3390/jmse12122370

Chicago/Turabian Style

Xu, Weiping, Bangrang Di, Haifeng Chen, and Jianxin Wei. 2024. "Experimental Analysis of Elastic Property Variations in Methane Hydrate-Bearing Sediments with Different Porosities" Journal of Marine Science and Engineering 12, no. 12: 2370. https://doi.org/10.3390/jmse12122370

APA Style

Xu, W., Di, B., Chen, H., & Wei, J. (2024). Experimental Analysis of Elastic Property Variations in Methane Hydrate-Bearing Sediments with Different Porosities. Journal of Marine Science and Engineering, 12(12), 2370. https://doi.org/10.3390/jmse12122370

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