Small Deformation Detected from InSAR Time-Series and Their Applications in Geophysics

InSAR has been proved to be useful for detecting large scale small surface motion from space. For a series of environmental phenomenon and their associated geomechanical processes, new insights are obtained from spatio-temporal information provided by InSAR. However, for some applications, how to get reliable deformation signal, how to use these information, and how to build the mechanical models remain some questions. For ice mass loss estimation problem, it is easy to build a linear inverse model from observed deformation. Unfortunately, this model is highly under-determined, which means the places far from the ice margin are usually poorly constrained while the places close to the ice margin are underestimated. For present-day hydraulic fracturing problem, only the upper crust is sensitive to the load change. But the existing global 1-D earth models usually have a coarse resolution in crust. Moreover, these models are typically from seismic wave velocities representing the dynamic moduli instead of the static moduli required for the hydraulic fracturing modeling. For geological carbon sequestration study, there was one successful attempt based on InSAR in the desert in 2008 and almost no new result comes out after that. The main problem is that most carbon sequestration projects are located in rural areas where less stable reflection targets can be found. In this dissertation I will try to answer the questions listed above. I will discuss two different methods solving the under-determined linear inverse problem for ice mass loss estimation in chapter 2 and 3. For the second question, I will discuss two different test sites and their crustal elasticity in chapter 4 and 5. In chapter 6 I will discuss the development of a time-series analysis method for retrieving small surface deformation at carbon sequestration injection sites in north America