*3.1. Identification of Glacially Flexured Areas*

To identify if a certain study area has been a ffected by glacially-induced flexure, we need information of the glaciation history. The lithospheric flexure is calculated based on the glacial isostasy (Figure 5), which is derived from the ice extent and thickness, as well as the properties and thickness of the lithosphere and mantle.

**Figure 5.** Derivative of the glacial isostasy used to identify areas of high flexural stresses.

Here, we will provide numerical models of flexure-related stress e ffects in the Hoop Fault Complex, located in the SW Barents Sea (Figure 6). The modelling will be limited to the stress e ffects related to the isostatic response during the deglaciation after LGM. For identifying the areas of SW Barents Sea that are a ffected by flexural stresses, we use the glacial isostasy of the LGM ice sheet calculated in Section 2 as input.

Based on the resulting glacial isostasy, we can identify the areas of maximum bending of the crust, and the hinge zones with minimum flexure. The derivation results of a function are illustrated in Figure 5. The first function illustrates the glacial isostasy on a vertical section through the lithosphere near the ice margin. The gradient (or tilt) can be derived from the first derivative of the glacial isostasy, the curvature or flexure of the lithosphere can be found by the second derivative.

The second derivative of the glacial isostasy of the LGM ice for the SW Barents Sea is shown in Figure 6. According to this, it is clear that the SW Barents Sea was greatly a ffected by lithospheric flexure during the deglaciation after LGM. There is a pronounced hinge zone (white area) extending from west of Bjørnøya over the Stappen High and into Loppa High. From here it extends eastwards over the Samson Dome onto the Finnmark Platform. Areas in the hinge zone are less likely to be affected by the flexural stress after the LGM deglaciation.

**Figure 6.** Second derivative, or curvature (m/km2), of the isostatic response of the LGM ice sheet (Figure 1) in SW Barents Sea license area (white square of Figure 2). Yellow, orange, and green areas have high curvature and are likely to be influenced by stress effects during and after the glaciation. (cf. Figure 5). The black square marks the area included in the stress modeling, and the blue arrows show the orientation of maximum flexure-related extension after LGM deglaciation within that area.
