Dyrham Formation

{{Use dmy dates|date=April 2022}}

{{Infobox rockunit

| name = Dyrham Formation

| image =Seatown_Beach_(geograph_2664120).jpg

| caption =

| type = Formation

| age = {{fossilrange|Pliensbachian}}

| period = Pliensbachian

| prilithology = mudstone, silt, sand

| otherlithology = ferruginous limestone

| namedfor = Dyrham

| namedby =

| region = England

| country = United Kingdom

| coordinates =

| unitof = Lias Group

| subunits =Eype Clay Member, Down Cliff Sand Member, Thorncombe Sand Member

| underlies = Beacon Limestone Formation, Marlstone Rock Formation

| overlies = Charmouth Mudstone Formation

| thickness = ~125 m

| extent =

| area = Wessex Basin, Worcester Basin, East Midlands Shelf

| map =

| map_caption =

}}

The Dyrham Formation is a geologic formation in England. It preserves fossils dating back to the early part of the Jurassic period (Pliensbachian).{{Cite web |url=http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=DYS |title=Dyrham Formation |last=British Geological Survey |website=BGS Lexicon of Named Rock Units |access-date=2018-03-08}}