Surmeh Fm

Period:

Jurassic

Age Interval:

Kimmeridgian – Tithonian, Ir (1,3)

Province:
Iran

Type Locality and Naming

Column: Zagros belt (general), Column: Iran East

Synonym:

Lithology and Thickness

2205 feet of dominantly massive-weathering, feature-forming dolomite and dolomitic limestone. Basal 300 feet is a massive dolomitic limestone with abundant shells. Overlying this is about 250 feet of relatively low-weathering, thin to medium-bedded, marly to silty, gray to brown, dolomitic limestone, with abundant gastropods, pelecypods, ammonites, and, worm casts. Upper 1665 feet of the formation consists of massive, feature-forming, fine-grained to coarsely crystalline, cherty dolomite and dolomitic limestone.

Lithology Pattern:

Dolomite

Relationships and Distribution

Lower contact

Regionally, the schematic strat column indicates the next older unit as Najmah Fm with an unconformity

Upper contact

Regionally, the schematic strat column indicates the next younger unit as Fahliyan Fm

Regional extent

GeoJSON

{"type":"Feature","geometry":{"type":"MultiPolygon","coordinates":[[[[46.14,35.51],[46.27,35.21],[46.08,34.99],[46.06,34.76],[45.68,34.43],[45.67,33.97],[45.98,33.77],[46.5,33.04],[47.67,32.53],[48.07,31.88],[48.06,31.11],[49.27,30.6],[50.32,30.21],[51.11,28.9],[52.49,27.64],[53.82,26.86],[54.7,26.57],[56.39,27.37],[57.04,27.03],[57.41,25.81],[58.36,25.63],[61.2,26.51],[62.63,27.27],[60.87,30.06],[60.74,31.52],[60.35,34.09],[60.87,34.93],[58.46,35.3],[56.64,34.8],[58.6,28.19],[46.14,35.51]]]]}}

Fossils

Age

Kimmeridgian – Tithonian

Age Span:

Beginning stage:

Kimmeridgian

Fraction up in beginning stage:

0.35

Beginning date (Ma):

152.84

Ending stage:

Tithonian

Fraction up in the ending stage:

0.25

Ending date (Ma):

147.71

Depositional setting

Depositional pattern:

Additional Information

Compiler:

Middle East Geological Timescale 2008 Al-Husseini, Journal of Middle East Petroleum Geosciences v 13, no. 4. James at. al., 1965, page 2188