Taylor Park and most of the surrounding high country along the Continental Divide consist of an uplifted core of ancient Precambrian igneous and metamorphic rocks. These Precambrian crystalline rocks are comprised of a basement complex of ancient metamorphic rock intruded by 1.7 billion year old orogenic granites and slightly younger 1.0 to 1.4 billion year old anorogenic granites. The metamorphic country rock crops out in a wide swath east and southeast of Taylor Park Reservoir. It consists of gneisses, schists, and quartzites that form some of the oldest rocks exposed in Colorado. The older of the two granites occurs south of Taylor Park Reservoir near Cross Mountain and northeast of the reservoir along the Continental Divide. Large exposures of younger anorogenic granite crop out north, west, and southwest of the reservoir along the Taylor River.
The uplifted Precambrian core of the central Colorado Rockies is intruded by numerous small Tertiary-age stocks, plugs, and plutons. In the Taylor Park area both Laramide and younger mid-Tertiary intrusions occur. Laramide intrusives crop out north of Taylor Park Reservoir along the Continental Divide while mid-Tertiary stocks occur west of the reservoir near Matchless Mountain and also southeast of the lake, near the site of Tincup.
A few miles west of Taylor Park Reservoir a large northwest-southeast trending fault cuts through the core of the mountains for nearly 20 miles. Just northwest of the reservoir the fault forms the contact between ancient granites and younger Pennsylvanian-Permian sedimentary rocks. West and southwest of the reservoir, older Cambrian-Mississippian sediments crop out along the fault.
The Taylor Park area is well endowed with mineral deposits. The richest district in the park is the famous Tincup Mining District which is located 6 miles southeast of Taylor Park Reservoir. Tincup is home to a swarm of polymetallic gold and silver-bearing veins and replacement bodies hosted within Paleozoic limestones and dolomites. These hypabyssal deposits crop out near the head of Willow Creek. The Tincup District also contains rich placer deposits derived from these veins and ore bodies. The Taylor Park Mining District also harbors extensive placer gold deposits which occur in most of the tributaries of the Taylor River near its head. These include Little Texas Creek, Hell's Gulch, Stiles Gulch, Pieplant Creek, Illinois Creek, Little Taylor Gulch, Alder Gulch, and Frenchmans Gulch. The Taylor Park placers contain native gold and an assortment of heavy minerals derived from the weathering of granite pegmatites. (These include grains of monazite, zircon, and garnet.) The source for the gold flakes, gold wire, and small nuggets found in these streams has never been found!
Taylor Park presents the modern-day gold-seeker with promising grounds to prospect. Virtually every tributary of the Taylor River near its head contains placer gold in some quantity. These include Red Mountain Creek, Pieplant Creek, Texas Creek, Hell's Gulch, Illinois Creek, Stiles Gulch, Little Taylor Gulch, Alder Gulch, and Frenchmans Gulch. All of these streams have their headwaters in the Sawatch Range which forms the Continental Divide in this part of the state. All of them cut through ancient Precambrian granite and metamorphic country rock. Although most of these streams are gold-bearing, the source for this placer gold has never been found.
Prospectors may want to focus on the many streams that feed into the Taylor River east and northeast of Taylor Park Reservoir. The area of interest is quite extensive, stretching from Red Mountain Creek southward to Willow Creek. Each of the streams in this part of Taylor Park merits special attention. Prospectors may want to systematically trace the course of each stream from its head to its junction with the Taylor River. W.D. Murdie made his remarkable discovery in the bed of one of these streams. It is quite possible that the 15-inch wide vein is still exposed there today.