Edit a page: Medusa Member

For Help in formatting please see the Wiki Help

Categories:
	1:		2:
	3:		4:
	5:		6:
	7:		8:
	9:		10:
Lithostratigraphy
	1:		2:
	3:		4:
	5:		6:
	7:		8:
	9:		10:
Chronostratigraphy
	1:		2:
	3:		4:
	5:		6:
	7:		8:
	9:		10:
Allostratigraphy
	1:		2:
	3:		4:
	5:		6:
	7:		8:
	9:		10:
Hydrostratigraphy
	1:		2:
	3:		4:
	5:		6:
	7:		8:
	9:		10:

Primary source[edit | edit source]

Willman, H. B., Elwood Atherton, T. C. Buschbach, Charles Collinson, John C. Frye, M. E. Hopkins, Jerry A. Lineback, and Jack A. Simon, 1975, Handbook of Illinois Stratigraphy: Illinois State Geological Survey Bulletin 95, 261 p.

Contributing author(s)[edit | edit source]

H. B. Willman and T. C. Buschbach

Name[edit | edit source]

Original description[edit | edit source]

The Medusa Member of the Pecatonica Formation (Templeton and Willman, 1963, p. 77).

Derivation[edit | edit source]

Named for the Medusa Cement Company plant, 2 miles northeast of Dixon, Lee County, which is 1.5 miles south of the type section.

Other names[edit | edit source]

History/background[edit | edit source]

Type section[edit | edit source]

Type location[edit | edit source]

The type section of the Medusa Member is in a quarry on the east side of the Rock River Valley (SW SW NW 22, 22N-9E), where the member is 5.2 feet thick.

Type author(s)[edit | edit source]

Type status[edit | edit source]

Reference section[edit | edit source]

Reference location[edit | edit source]

Reference author(s)[edit | edit source]

Reference status[edit | edit source]

Stratigraphic relationships[edit | edit source]

Extent and thickness[edit | edit source]

In the northern outcrop area the Medusa Member is commonly 5-7 feet thick, but it thickens to 20 feet in extreme southern Illinois.

Lithology[edit | edit source]

In the outcrop area the Medusa Member consists of dolomite or of limestone heavily mottled with dolomite. It is slightly argillaceous, very fucoidal, and thick bedded to massive. South of Ogle County it contains chert nodules.

Core(s)[edit | edit source]

Photograph(s)[edit | edit source]

Contacts[edit | edit source]

Well log characteristics[edit | edit source]

Fossils[edit | edit source]

Age and correlation[edit | edit source]

Environments of deposition[edit | edit source]

Economic importance[edit | edit source]

Remarks[edit | edit source]

Reference(s)[edit | edit source]

place a <pre><br></pre>at the end of a line to get a line return TEMPLETON, J. S., and H. B. WILLMAN, 1963, Champlainian Series (Middle Ordovician) in Illinois: Illinois State Geological Survey Bulletin 89, 260 p.

Membercode:
Geo_unit:
Geo_image:	Upload file

Save page Show preview Show changes Cancel