  Recently, the focus of reflection seismologists has shifted to applications
where a high-resolution image of the subsurface is required. Least-Squares
Reverse-Time Migration (LSRTM) is a common tool used to compute such images.
Still, its high computational costs have led seismologists to use
target-oriented LSRTM for imaging only a small target of interest within a
larger subsurface block. Redatuming the data to the upper boundary of the
target of interest is one approach to target-oriented LSRTM. Still, many
redatuming methods cannot account for multiple scattering within the
overburden. We apply a target-oriented least-squares reverse time migration
algorithm that integrates Marchenko redatuming and double-focusing to a field
dataset. This redatuming method accounts for all orders of multiple scattering
in the overburden, thus improving the accuracy of target-oriented LSRTM.
Moreover, we demonstrate the effectiveness of a double-focusing algorithm in
reducing the data size by decreasing both spatial and temporal dimensions of
the model and the data. The algorithm's performance is evaluated using field
data acquired in the Norwegian Sea. The numerical results show that our
target-oriented LSRTM algorithm can reduce the internal multiple effects and
increase the resolution of the resulting image.
