Multi-Condition Guided Diffusion Model for Controllable Elastic Parameter Synthesis
可控弹性参数合成的多条件引导扩散模型
Hongling Chen, Qi Pang, Chuangji Meng, Shian Shen, Jinghuai Gao
AI总结 提出多条件引导扩散模型,利用井统计和地质特征构建训练数据集,通过隐变量细化、适配器条件和扩散后验采样投影引导策略,实现弹性参数的可控合成与反演。
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叠前弹性参数反演对于储层表征和定量地震解释至关重要。现有大多数基于深度学习的方法已取得有希望的结果,但它们通常需要足够的标记训练数据,并且在整合多源条件信息方面灵活性有限。为了解决这个问题,我们提出了一种用于可控弹性参数合成的多条件引导扩散模型。首先基于目标区域的测井统计和地质特征构建弹性参数训练数据集,并用于训练扩散模型。然后开发了一个统一的多条件引导扩散框架,以整合隐式和显式条件信息。具体地,引入了迭代潜变量细化、基于适配器的条件以及扩散后验采样(DPS)-投影引导策略,分别用于隐式模型域约束、隐式结构约束和显式条件算子约束。合成示例表明,所提出的方法可以在单条件和多条件引导下生成与规定条件一致的弹性参数样本。当使用地震数据作为条件信息时,该框架可进一步适用于地震弹性参数反演。实验表明,与基线方法相比,所提出的方法改进了代表性弹性参数(包括纵波速度、横波速度和密度)的预测。合成的样本还可以在有限标记数据下支持下游基于深度学习的反演,实现有竞争力的性能。
Prestack elastic parameter inversion is important for reservoir characterization and quantitative seismic interpretation. Most existing deep-learning-based methods have achieved promising results, but they generally require sufficient labeled training data and have limited flexibility in integrating multi-source conditioning information. To address this issue, we propose a multi-condition guided diffusion model for controllable elastic parameter synthesis. Elastic parameter training datasets are first constructed based on well log statistics and geological characteristics of the target area and are used to train the diffusion model. A unified multi-condition guided diffusion framework is then developed to incorporate both implicit and explicit conditioning information. Specifically, iterative latent variable refinement, Adapter-based conditioning, and a diffusion posterior sampling (DPS)-projection guidance strategy are introduced for implicit model-domain constraints, implicit structural constraints, and explicit conditioning-operator constraints, respectively. Synthetic examples demonstrate that the proposed method can generate elastic parameter samples that are consistent with the prescribed conditions under both single-condition and multi-condition guidance. When seismic data are used as conditioning information, the framework can be further adapted to seismic elastic parameter inversion. Experiments show that the proposed method improves the prediction of representative elastic parameters, including P-wave velocity, S-wave velocity, and density, compared with baseline methods. The synthesized samples can also support downstream deep-learning-based inversion under limited labeled data, achieving competitive performance.