English: (See file name).
(Photo: "Unkar Creek Delta, on Colorado River, near the start of the basement rocks in Grand Canyon." (the start is just upstream)
The horizontal cliff at top of the 15 degree, angular unconformity, is the en:Tapeats Sandstone. 4 Horizontally laid (deposited) layers are shown in this photo below the en:Tapeats Sandstone. The top layer is at photo top-right. The first 2 layers are in Grand Canyon Supergroup-(of 4 units). (#3 of 4)-Chuar Group, (#2 of 4)-Nankoweap Formation, (3 and 4, are layers No. 5/6 of the en:Unkar Group)-(unit #1 of 4 in the Supergroup(Unkar Group), (unit 6 of 6)-en:Cardenas Lava, (unit 5 of 6)-Dox Formation.

The 4-layers are conformablly laid, no timegaps. The contact above the Sixty Mile Formation (unit 4 of 4)/Chuar Group is a en:fault (geology) with Vishnu Schist, mostly found later downstream, (another fault), in the Granite Gorge-(but with the bottom units of the series, (the lowest of Unkar Group, unit 1 of 6)).
Note: Basalt Creek delta, is in the Dox Formation, the cliffs directly up creekside, go into the overlying Cardenas Lava, maybe 40-80 ft(?) thick, at creekside, but the Cardenas Lava in places is up to 800 ft thick.