A fibrous silicon carbide substrate is disclosed that is formed from a reaction between carbon fibers and silicon additives, to provide in-situ silicon carbide fibers. The fibrous structure is formed from a paper-making process of carbon or organic fibers that form a plurality of lamination members. The lamination members, each having a plurality of through holes, that when aligned in a lamination direction, form a honeycomb array of channels. The lamination members can be adapted into a wall-flow configuration for use in filtration of the exhaust of internal combustion engines.