Induced fractures often form during the coring of the rock. These need to be captured during a core description as should not be confused with those natural fractures that can actually contribute to the permeability of the reservoir. Have a look at this blog for some criteria you can use to distinguish between the 2…

http://www.ogilviegeoscience.co.uk/blog/2022/12/4/natural-vs-induced-fractures-in-rock-core

Induced fractures are often irregular and sinuoidal..

Some examples are provided here from the BGS core photograph database - from 2 wells in the Britannia Field (Central North Sea). The large aperture fractures in Fig. 1. are particularly striking. Their interaction with the rock fabric is interesting - note how the clay partings that run sub-parallel to the bedding appears to have affected the development of a fracture (red arrow on Fig. 1). These fractures are also quite sinuous in appearance (just above “DTI cut” text in Fig 2a and in Fig. 2b).

Given that these are observations from BGS photographs, we would need to visit the core store to carry out a more detailed analysis on the core itself.

Fig. 1. Induced fractures ? in sandstone in Britannia well 15/30-13
*British Geological Survey © UKRI*
https://largeimages.bgs.ac.uk/iip/index.html?id=20120104/S00156619

Fig 2. Induced fractures ? in sandstone in Britannia well 15/30-13 from 14516 - 14522 ft. Upper: red box shows location of Fig 1. Arrows show way up.
*British Geological Survey © UKRI*
https://largeimages.bgs.ac.uk/iip/index.html?id=20120104/S00156619
https://largeimages.bgs.ac.uk/iip/index.html?id=20120104/S00156620

Some induced fractures have distinctive geometries (e.g., petal, disc)

There is quite a regularity to the pattern in Fig. 3 which is from sandstone core in another well from the Britannia Field. I’m uncertain as to whether or not these are induced - although it does look like sections through common petal fractures which are induced by the weight of the bit on the rock formation during coring. There are some useful diagrams on P85 of Lorenz and Cooper [1] to help with this.

Alternatively, these could be fault-related (i.e. natural) which I think is unlikely given that Britannia has few natural (open) fractures and I wouldn’t expect this type of fracture pattern in that case. Note also how quickly the fracture zone transitions into an undeformed host sandstone (Fig. 3) which is a further line of evidence.