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NEW MEXICO

The Lost Jicarita Mine

GEOLOGY OF THE AREA


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The Sangre de Cristo Mountains are the longest mountain chain in the Rocky Mountain Cordillera. They extend for over 200 miles in a northwest-southeast direction through south-central Colorado and north-central New Mexico. The Sangre de Cristo Mountains are one of the youngest ranges in America. As incredible as it may seem, the towering peaks of the Sangres began their journey upward less than 30 million years ago. And of course, they are still rising today. The Sangres consist of a core of ancient Precambrian basement rock made up of various metamorphic rocks intruded by slightly younger granite. The metamorphics are about 1.7 billion years old and consist mostly of gneisses with variable

amounts of metasedimentary and metavolcanic rocks. South of Wheeler Peak, the Sangre de Cristo mountain block experienced less dramatic uplift, consequently it still retains its mantle of Pennsylvanian sedimentary rocks. Jicarita Peak is part of this southern block, indeed, the peak itself is composed of Pennsylvanian sediments. But Precambrian basement rock crops out close by. An exposure of Precambrian crystalline rocks occurs just a few miles east of Jicarita Peak in Mora County. The Sangre de Cristo Mountains are host to several major faults and fault systems. A major northwest-southeast trending fault cuts through much of the range just a few miles northeast of Jicarita Peak.

PROSPECTING POTENTIAL

The Sangre de Cristo Mountains consist of a core of ancient Precambrian basement rock overlain by Pennsylvanian-age sedimentary rocks in the southern portion of the range. As mentioned previously, Jicarita Peak is part of this terrane of younger Pennsylvanian sediments. Precambrian metamorphics crop out east of the peak, in Moro County. Prospectors may want to concentrate on these ancient rocks. The headwaters of the Rio La Casa and Lujon Creek are home to many small gold-bearing quartz veins. This area is very close to the area of interest, in fact, only about 6 miles southeast of Jicarita Peak. Similar gold-bearing veins may occur in the metamorphic country rock just east of the peak.


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It is always possible that a fossil gold placer exists somewhere within the Pennsylvanian sandstones that cloak the slopes of Jicarita Peak. Such a thing occurs in the Villanueva area, located on the Pecos River southeast of Sena. The fossil placers were found in a cliff-forming Permian sandstone overlooking the river, but the deposit proved to be too marginal to develop.