## 1 Introduction
In recent years, the sensitivity kernels of coda waves, in 2D and 3D, propagating in a medium with a realistic velocity model, were computed by numerical simulations following Yoshimoto [17]: assuming that the total seismic energy is subdivided in particles of unit energy that are randomly emitted from the source, the energy particle loses a fraction of its energy by anelastic absorption. When the energy particle encounters an elastic and isotropic scatter, it randomly changes its direction. After a number of collisions, it will arrive at the receiver at a given lapse time, measured from the origin time. Thus, the energy envelope is the sum of the energy particles arriving at the receiver from random directions at a given lapse time, sampling a portion of the Earth's volume. Thus, it can be heuristically assumed that the more a volume element (in which the whole medium is divided) is crossed by energy particles, the more it weighs in the energy envelope of each seismogram. The space weighting function can be calculated in the whole propagation volume by counting the number of crosses and collisions of the energy particles in each volume element [11]. In the last few years, sensitivity kernels for scattering radiation have been used to image both volcanic structures [18; 19; 20] and tectonically active zones (e.g., [21; 22]). The first attempt to study the \(Q_{c}\) attenuation in the Gargano Promontory (Northern Apulia, Southern Italy) (hereafter GP) has been performed using a dataset of microearthquakes recorded by the OTRIONS Local Seismic Network (OT), managed by UniBa, in the period from April 2013 to July 2014 [23]. The obtained 2D image of \(Q_{c}\) revealed the presence of a well-resolved \(Q_{c}\) anomaly in the southwestern sector of the GP, at \(f_{c}>5\) Hz. The southwestern sector of the GP is characterized by the presence of fluid circulation in fractures at shallow crustal levels, as also revealed by 2D resistivity imaging [24] and by the heat flow map [25], which can cause both scattering and intrinsic attenuation effects on a local scale. The heterogeneity of the GP crust was recently highlighted by a local-scale seismotectonic study [26], thanks to a recently released dataset of microearthquakes recorded by both the National Seismic Network (IV), managed by the INGV, and the OT network in the period from August 2015 to August 2018 [27]. The authors [26] analyzed all possible focal mechanisms and found a great heterogeneity of solutions in the seismicity of the upper and intermediate crust; however, in the lower crust, the seismicity appears more concentrated in the NE sector, which is consistent with a thrust-faulting stress regime with maximum compressive axis (\(S_{thmax}\)) that is NW-SE oriented, and a shallow normal-faulting stress regime with a maximum horizontal compressive axis (\(S_{thmax}\)), trending NW-SE [28]. The historical seismicity of northern Apulia reveals seismogenic structures that can generate destructive events. Among these, the 1627 earthquake (with an intensity X degree MCS and estimated magnitude of 6.7) and the 1646 earthquake (with an intensity IX-X degree MCS at Carpino and estimated magnitude of 6.2) [29]. Concerning the tectonic structures, many faults are recognized along the entire GP surface, the characteristics of which are poorly known. In Figure 1, we report the seismotectonic map of Italy ([30]) and the details on the GP sector, with the principal tectonic lineaments that could be responsible for the main historical earthquakes. Considering these recent results [26], related to the strong lateral and vertical crustal heterogeneity of the GP, in this paper we performed a new and more robust study of \(Q_{c}\) in order to address some still open questions: the first is the reason for the presence of lower crustal seismicity in the NE sector of the GP, with the absence of shallower seismicity; the second is the presence of very shallow seismicity in the SW sector of the GP, and its relationship with fluid circulation in the upper crust.