Which factor can increase the porosity of sedimentary rocks?

The presence of larger particle sizes can increase the porosity of sedimentary rocks because larger grains create more space between them when they are deposited. This interstitial space, or voids, is where fluids like water or oil can be stored, leading to higher porosity. In sedimentary environments, when larger particles settle, they don't pack as tightly together as smaller particles would, resulting in a greater amount of pore space.

Additionally, this relationship can be understood in the context of sediment sorting. Well-sorted sediments, which consist of uniform grain sizes (and often larger grains), tend to have higher porosity compared to poorly sorted sediment, where a mix of particle sizes fills the voids, reducing overall pore space. Thus, the characteristic of the sediment—its grain size—significantly influences the porosity of the resulting rock.