Thus far it all sounds so simple, if only it was! Many of the formations named in the 1800’s and early 1900’s do not have precise type localities let alone a type section. For example, the Fountain Formation was named (Cross, 1894) for “typical development on Fountain Creek below Manitou Springs and at head of Fountain Creek, El Paso Co, CO”. So, we know about where the type locality is located but we have no type section. The Graneros Shale, named by G. K. Gilbert in 1896 when studying rocks east of Pueblo, also does not have a type section nor a type locality. However, workers at the U. S. Geological Survey have designated a “principle reference section” in lieu of a type section and allowed by the Code. Another interesting occurrence is with the Eagle Valley Evaporite Member of the Minturn Formation first named in 1958 from Eagle County, CO. It was redefined and elevated to Eagle Valley Evaporite in 1962, was changed to the Eagle Valley Formation in 1968, and then back to the Eagle Valley Evaporite in 1971, its current usage (I think). Perhaps beauty (or the name of a formation) is in the eye of the beholder!
At times geologists find it advantageous to subdivide formations into formal members in order to highlight rock units of special interest. A formation need not be subdivided into members although some will be completely divided while others will have only certain parts named. For example, the Niobrara Formation exposed along the Front Range is divided into the lower Fort Hays Limestone and the upper Smoky Hill Chalk members. As with formations, the unit has a compound name with a geographic “first” name and the term member or a rock term as the ‘second” name. At other times, geologists may find it advantageous define informal members-- the Colorado Geological Survey maps and divides the Upper Cretaceous Laramie Formation at Colorado Springs into the upper member, the middle sandstone member, and the lower member. One can distinguish between formal members and informal members by noting capitalization (or lower case) of the initial letter of each term.
Members may be further subdivided into beds with naming rules similar to formations and members. Most beds that I am familiar with have an economic significance, such as some of the beds in the Green River Formation (Eocene of northwestern Colorado).
And finally, two or more formations may be combined into a group with the compound name consisting of a geographic term and the word Group. For example, the Benton Group consists of the Carlile Shale, Greenhorn Limestone, and Graneros Shale. Groups are commonly employed on large scale maps.
It also might be of interest to examine type localities of other formations exposed near Colorado Springs: 1) Dawson Formation  no type locality but named for Dawson Butte near Castle Rock, CO; 2) Laramie Formation ---no type locality, “exposed along Front Range”; 3) Fox Hills Sandstone ---no type locality, named for Fox Hills near Fort Pierre, SD; 4) Pierre Shale ---no type locality, named for Fort Pierre, SD; 5) Niobrara Formation ---no type locality, named for exposures near mouth of Niobrara River, NE; 6) Carlile Shale ---no type locality but named for Carlile Station and Carlile Springs 21 west of Pueblo, CO; 7) Greenhorn Limestone ---no type locality, named for Greenhorn Creek and Greenhorn Station, CO; 8) Graneros Shale ---no type locality and no name derivation but USGS has named a Principal Reference Section in CO; 9) Dakota Sandstone ---no type locality, named for Dakota, NE but type designated by Nebraska Geological Survey; 10) Purgatoire Formation ---no type locality, named for Purgatoire Canyon, CO; 11) Morrison Formation ---no type locality, named for Morrison, CO; Colorado geologists have designated a type section; 12) Lykins Formation ---no type locality, named for Lykins Gulch, Boulder, CO; 13) Lyons Sandstone ---no type locality, named for Lyons, CO.
Gilbert, G.K., 1896, The underground water of the Arkansas Valley
in eastern Colorado, IN Walcott, C.D., Seventeenth annual
report of the United States Geological Survey to the Secretary
of the Interior, 1895-1896; Part II: U.S. Geological Survey
Annual Report, 17, pt. 2, p. 551-601.