* Formation: Petrified wood forms when trees are buried in sediment, like volcanic ash or mud. The wood slowly decays, and the organic material is replaced by dissolved minerals, typically silica (quartz). This process occurs in a sedimentary environment.

* Process: The replacement of organic material with minerals is a process called "permineralization," which is a key characteristic of sedimentary rock formation.

* Structure: Petrified wood retains the original structure of the wood, with preserved growth rings, grain patterns, and sometimes even bark. This preservation occurs within the layers of sediment.

It's important to note: While petrified wood is a sedimentary rock, it can be found within areas of igneous or metamorphic rock. This is because the original wood may have been buried in volcanic ash (igneous) or later subjected to heat and pressure (metamorphic) after the fossilization process.