Brancaccio et al. (1979)
They are the first investigators to describe the Boiano Basin as 
having formed during a tectonic phase that has operated since the 
Middle Pleistocene. They also point out that the marginal portions 
of the basin are characterised by hanging deposits associated with 
sub-planar relict surfaces, such as in the case of SW-dipping (that 
is, dipping towards the Matese Mts.) lacustrine deposits cropping 
out in the S. Massimo area at about 800 m elevation (nearly 300 m 
above the alluvial plain). Thanks to the presence of pyroclastic 
deposits within the lacustrine sequence, they date this complex at 
1.0-1.5 Ma.

Esposito et al. (1987)
They describe in detail a number of historical reports of surface 
effects of the 1805 earthquake including changes in spring 
discharge, sulfur exhalations, and degassation phenomena that 
were observed over a distance of about 50 km between Isernia 
and the Morcone Plain.

Russo and Terribile (1995)
They describe the geomorphology of the Boiano Basin and contend 
that it is filled by a sequence of fluvial-lacustrine Quaternary 
sediments ranging in thickness between a minimum of 160 m to a 
few hundred meters. According to these investigators the Boiano 
Basin is a Lower to Middle Pleistocene, relatively undeformed, 
feature carved into an older depression generated by a different 
tectonic regime.

Cucci et al. (1996)
These workers investigate the drainage pattern of the area 
to detect anomalies that could be interpreted as the effect of 
repeated slip on a large deep-seated normal fault. The existence of 
a fault with these characteristics is required by the seismicity of 
the area and particularly by the occurrence of the large 26 July 
1805 earthquake. Their analysis points out that the centripetal 
pattern of drainage inside the basin, as well as the mere presence 
of the basin itself, is consistent with sustained slip along a ca. 20 
km-long, NW-SE striking, NE-dipping, blind normal fault having 
the basin on its hanging-wall. Their model fault projects near 
the southwestern side of the basin, along the foothills of the 
Matese Massif.

Corrado et al. (1997) and Ferranti (1997)
These investigators describe a drastic Middle Pleistocene change 
in the regional stress field after which SW-NE extension becomes 
the dominant tectonic regime. According to Corrado et al. (1998), 
the new stress configuration is responsible for the formation of an 
important system of NW-SE-trending normal faults, but also for 
the reactivation of existing strike-slip faults with opposite sense 
of shear and with a dip-slip component.

Ascione and Cinque (1997) and Cinque (1998)
These papers describe many scarps on faults (which, according 
to the definition of Ascione and Cinque (1997) include faults 
scarps and fault-line scarps) bounding the Boiano Basin; they 
interpret most of them as fault line scarps due to selective 
exhumation of tectonic contacts derived from pre-extensional 
tectonic activity. 

Ascione et al. (1998)
They suggest the existence of remnants of terraces located around 
the Boiano Plain at slightly higher elevation with respect to it, and 
contend they were originated by unspecified tectonic activity.
They also describe NW-SE striking faults displacing the fluvial-
lacustrine basin filling deposits as much as a few tens of meters at 
unspecified locations near the NE and SW margins of the 
basin. They also report that the northeastern side of the basin 
is affected by NW-SE and SW-NE trending  rectilinear scarps 
uplifting an erosional glacis cut in soft flysch deposits. 

Basili et al. (1999)
These investigators analyse the elevation relationships between 
strath terraces (at lower elevations) and relict surfaces (at higher 
elevations) that exist all around the basin. They find that 
correlation is possible for the lower terraces, which are seen at 
roughly the same elevation regardless of their location, but not for 
the relict surfaces, which form a separate sequence in the 
southwestern part of the basin. They conclude that this last 
sequence must be separated from the others by a primary normal 
fault running along the SW margin of the basin and dipping 
towards the NE.

Blumetti et al. (1999)
They describe about 50 contemporary reports of surface breaks 
and other surface effects related with the occurrence of 
the 1805 earthquake. In particular they refer to contemporary 
sources describing the inception of new springs, sulfur 
exhalations, and degassation phenomena leading to the 
death of vegetation along sub-linear features (these 
occurrences are described more extensively in Esposito et al. 
(1987)). According to these investigators, the surface 
phenomena suggest that the 1805 earthquake sequence was 
generated by a set of faults rupturing for a total length of 
nearly 50 km from Isernia to the Morcone basin.

Gasperini et al. (1999)
They model the well-documented damage pattern of the 1805 
earthquake through an analytical approach. Their modelling 
returns an equivalent magnitude Me of 6.5, a rupture length of 
about 25 km, an orientation of the source area of 124+/-27, and 
a location of the surface projection of the seismic source almost 
coincident with the basin itself. 

Blumetti et al. (2000)
They opened a trench at locality Il Lago, about 1 km NE of 
Pettoranello del Molise and near the northern end of the region 
affected by the large 1805 earthquake. Two faulting events are 
identified in the sedimentary sequence, the most recent of which 
generated 10-15 cm of surface displacement. The two events are 
interpreted as being compatible with the presumable height of a 
scarp generated by the 1805 earthquake, but no age constraints can 
be derived for them from the paleoseismological analysis.

Di Bucci et al. (2001)
These investigators contend that the development of the Boiano 
Basin is controlled by the simultaneous generation of new faults 
and reactivation of pre-existing ones under roughly NE-SW regional 
extension. They also point out that no unambiguous surface 
evidence of the seismogenic source has been identified so 
far. The extensional system is formed by two principal fault 
families. Faults of the first and main family strike NW-SE, show dip-
slip features and are interpreted as the direct response to extension 
acting in the region since the Middle Pleistocene. Faults of the 
second family strike E-W and have high-angle or vertical dips; two 
clearly distinct generations of slickensides record both pure strike-
slip, mainly left-lateral (older) and normal-oblique (newer) 
movement. According to these investigators, this second family 
of faults operated over a much longer time span than the first 
family, suggesting that they play only a passive role under the 
present tectonic conditions. They also propose a geological cross-
section based on the joint interpretation of a variety of observations 
including oil industry reflection seismology data. The section shows 
a complex pattern of synthetic and antithetic extensional faults 
related to master fault dipping towards the NE at an angle of 50 to 
60 and extending to a depth of at least 8 km (inferred 10 km: 
corresponding fault width is 13 km). The hanging-wall of the 
master fault hosts the Boiano Plain and the Quaternary sediments 
that partially fill the depression beneath it. The section shows that 
the architecture of these deposits is asymmetric as their thickness 
increases towards the SW (that is, towards the main fault). Total 
displacement along the master fault is reported to be limited (no 
more than a few hundred meters).In contrast with Esposito et 
al. (1987) and Blumetti et al. (1999), Di Bucci et al. (2001) propose 
that the 1805 rupture terminated against two significant segment 
boundaries located between Carpinone and Mt. Patalecchia and 
between Guardiaregia and the Vinchiaturo Pass, respectively to the 
NW and SE. The 1805 earthquake would thus have been a Mw 6.6-
6.8 event caused by a 25 km-long, 13 km-wide normal fault 
rupture.
