Konstantinou K I
Dept of Earth Sciences, National Central University, Jhongli, 320, Taiwan.
Sci Rep. 2024 Jul 30;14(1):17593. doi: 10.1038/s41598-024-67724-0.
The temporal evolution of dike volume can help elucidate its propagation dynamics, however, such an estimation is possible only when there are geodetic observations available along the dike path. Here it is shown that dike volume history during eight eruptions can be reconstructed from seismic moment release using high resolution earthquake catalogs. The critical volume needed for each dike to reach the surface is simulated and compared to the accumulated volume prior to eruption in order to infer fracture toughness, a measure of resistance to fracture. It is found that fracture toughness varies between 123-833 MPa m , with larger values corresponding to longer dikes. Resistance to fracture dominates over viscous dissipation when the dikes propagate through unfractured heterogeneous material with large rigidity contrast, or when there is dike segmentation. These results can be utilized for real time monitoring of dike growth, forecasting eruption volume, and for constraining analog or numerical models of dike propagation.
岩脉体积的时间演化有助于阐明其扩展动力学，然而，只有当沿岩脉路径有大地测量观测数据时，才有可能进行这样的估算。本文表明，利用高分辨率地震目录，通过地震矩释放可以重建八次火山喷发期间的岩脉体积历史。模拟了每条岩脉到达地表所需的临界体积，并将其与喷发前积累的体积进行比较，以推断断裂韧性，这是一种抗断裂能力的度量。研究发现，断裂韧性在123 - 833兆帕·米之间变化，值越大对应岩脉越长。当岩脉穿过具有大刚度对比的未破裂非均质材料时，或者当存在岩脉分段时，抗断裂能力超过粘性耗散。这些结果可用于岩脉生长的实时监测、喷发量预测以及约束岩脉扩展的模拟或数值模型。
