Muddy Creek Contacts with the Lavas

35.947022,-114.790558
We verify what the geologic maps says that the lavas are on top of the Muddy Creek lake bottoms just to keep them honest. Their theory relies on superposition.

We saw signs of this lake bottom on the video "Take the Scenic Route" above Hoover Dam on the other side of these lava flows.

Free Geologic Map of the area:
https://pubs.usgs.gov/of/2013/1267/a/

Tsmo--Mudstone, siltstone, east of Boulder City, where it contains conspicuous manganiferous gypsum in vicinity of Boulder Rifle and Pistol Club. Inferred to be about 12 to 16 Ma in age. unit lies between andesite lava and breccia of lower part of Patsy Mine Volcanics (Tpl) with an 40Ar/39Ar age of 15.72±0.03 Ma (Faulds and others, 1999) and a basalt flow of upper Mount Davis Volcanics (Tdmu) with an 40Ar/39Ar age of 12.73±0.3 Ma (

Tdmm--Black olivine basalt to basaltic andesite, Outcrops previously mapped as Fortification Basalts west of Colorado River (units Tmf, Tmfc, and Tmfq of Ekren and Anderson, 1996, and unit Tmf of Anderson, 1977, 1978) have been assigned to this unit based on stratigraphic relations and geochronology. A new 40Ar/39Ar age of 13.268±0.032 Ma (appendix 1) was obtained from basalt sample collected about 1.5 miles northeast of Boulder City from outcrops that had previously been mapped as Fortification basalt (Anderson and Ekren, 1996; Anderson, 1977).

Tdru--Rhyodacite, Lava of No Name Mesa (unit Tl of Ekren and Anderson, 1996), and unnamed flows and domes on east side of Black Canyon south of Palm Tree canyon (unit Tdr of Anderson, 1978). Sugarloaf dacite is 13.11±0.02 Ma (40Ar/39Ar; Faulds and others, 1999), and Lava of No Name Mesa is 13.10±0.10 Ma

Black Betty on Youtube:
https://www.youtube.com/watch?v=4cn_woPvjQI