Blended acquisition offers significant cost and period reduction in seismic data acquisition. However, fired blended sources are usually deployed at off-the-grid (OffG) samples due to obstacle limitation and economic cost considerations. The irregular distribution of coordinates, along with the blending noise, has a detrimental effect on the performance of subsequent seismic processing and imaging. The interpolated multichannel singular spectrum analysis (I-MSSA) algorithm effectively provides on-the-grid deblended results by employing an interpolator, in conjunction with a projected gradient descent strategy. However, the deblending accuracy and computational efficiency of the I-MSSA are still a concern due to the limitations of the traditional singular value decomposition (SVD). To address these limitations, we propose an interpolated fast damped multichannel singular spectrum analysis (I-FDMSSA) rank-reduction algorithm. The proposed algorithm incorporates the damping operator, the randomized SVD (RSVD) and the fast Fourier transform (FFT) strategy. The damping operator can further attenuate the remaining noise in the estimated signal obtained from the truncated SVD, resulting in an improved deblending performance. The RSVD accelerates the rank-reduction process by shrinking the size of the Hankel matrix. To expedite the rank-reduction and anti-diagonal averaging stages without explicitly constructing large-scale block Hankel matrices, the FFT strategy is employed. By incorporating a 2D separable sinc interpolator, the I-FDMSSA enables an efficient and accurate deblending of 3D OffG blended data. The deblending performance and operational efficiency improvements of the proposed I-FDMSSA algorithm over the traditional I-MSSA algorithm are demonstrated through OffG synthetic and field blended data examples.

混合采集可显着缩短地震数据采集的成本并缩短周期。然而，由于障碍物限制和经济成本考虑，燃烧混合源通常部署在离网（OffG）样本上。坐标的不规则分布以及混合噪声对后续地震处理和成像的性能产生不利影响。插值多通道奇异谱分析 (I-MSSA) 算法通过采用插值器并结合投影梯度下降策略，有效地提供网格去混合结果。然而，由于传统奇异值分解（SVD）的局限性，I-MSSA 的去混合精度和计算效率仍然是一个问题。为了解决这些限制，我们提出了一种插值快速阻尼多通道奇异谱分析（I-FDMSSA）秩降低算法。所提出的算法结合了阻尼算子、随机SVD（RSVD）和快速傅立叶变换（FFT）策略。阻尼算子可以进一步衰减从截断的 SVD 获得的估计信号中的剩余噪声，从而提高去混合性能。 RSVD 通过缩小 Hankel 矩阵的大小来加速降级过程。为了在不显式构造大规模块 Hankel 矩阵的情况下加速降阶和反对对角平均阶段，采用了 FFT 策略。通过结合 2D 可分离 sinc 插值器，I-FDMSSA 能够高效、准确地对 3D OffG 混合数据进行去混合。 通过 OffG 合成和现场混合数据示例证明了所提出的 I-FDMSSA 算法相对于传统 I-MSSA 算法的去混合性能和运行效率的改进。