The Rocks of Paradise!

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(I am also interested in GEOLOGY and ROCKHOUNDING)

An unusual name for geologists to give to a layer of volcanic rocks, but they deserve the name.





If you are lucky enough to find a piece of the surface material you will see a fairly flat surface covered with small crystals everywhere. They appear to be a variety of titanium, magnetite, and silica.





Surprising how they had many layers and bent around corners. It must have been a tough neighborhood!

They come in an endless array of patterns and  a few colors - red, yellow, purple, green -

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15 to a page is plenty. You may have noticed they are from the same formation, but NOT the same location.

Continuing on -

Note the broken shards of lava in the welded ash flow.

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How they Were Formed:

Ash Flow Tuffs

Most rocks are boring. Boulders, gravel, sand, clay, dirt, mud.

They are 99.9% formed from just 16 elements.





"You can't get blood out of a turnip." So, unless something really unusual happens, all you find is sand, clay, shale, . . .

How unusual? Every hundred years a star somewhere in our galaxy goes nova or supernova, hurling new elements into space. Small stars emit light elements - helium, carbon, oxygen. Middle size stars emit iron, nickle, titanium. Stars at least 8 times the size of our sun eject silver, and huge stars emit gold, platinum, and the really heavy elements.

The heavier the element, the more gravitational power it has, so the new atoms in space attract each other and they begin forming comets. Comets are attracted to stars and their planets.
Upon entering solar systems, comets break up into asteroids and meteors.

The contents of our planetary space is constantly changing. At present many of the meteorites we recover are nickle-iron, but there is a huge variety that we seldom hear about.

A billion years ago some huge asteroids crashed into earth. They made huge craters, evaporated along with a more or less equal amount of native rock. Those heavy clouds hung over the area, condensed, and rained gold, silver, whatever else was in the asteroid,
. . . and for the past thousand years we have been mining those ancient layers.

Occasionally a volcano vein will pass through a valuable buried asteroid impact site, melt the material and take it to the surface, but not often. Most of them still remain undetected.

The Rocks of paradise are a very unusual variety of a very unusual rock type!
Sedimentary, Metamorphic, Igneous. The later produces Lava, Ash Fall, Ash Flow AND WELDED ASH FLOW.

Even welded ash flow is usually boring. You can read about it here:

pubs.usgs.gov/pp/0354f/report.pdf

en.wikipedia.org/wiki/Tuff

Or watch this:

player.slideplayer.com/14/4275601/#

The Rocks of Paradise were formed 22 million years ago, born from the Pinto Peak Volcano.

The small town of Pinto looking southeast to Pinto Peak.



Looking down at the volcano:

Rocks of Paradise Tuff

pubs.geoscienceworld.org/geosphere/article-lookup/10/3/534

The Pinto Peak intrusion is unusual as the country rock bedding contacts are not deflected toward or into parallelism with the intrusion margins and the country rocks are not folded due to emplacement of the intrusion. Hacker et al. [2002] argued that the intrusion likely intruded from the north into the Cretaceous Iron Springs Formation and then stepped up section into the Tertiary Claron Formation to the south (Figure 2). Based on the AMS data reported here, this scenario is difficult to reconcile if the magnetic fabrics reflect magma flow into and/or away from the vent area. We envision an alternative scenario that adequately explains the observed fabric data from the main intrusive phase. Furthermore, we speculate on the relation between the fabrics in the vent facies to the main intrusive phase of the Pinto Peak intrusion. We propose that the fabric data from the northern part of the intrusion reflects magma flowing away from the vent area after it became blocked. The steep fabric data from the southern part of the intrusion reflects the likely ascent site of magma from depth that fed the intrusive phase as well as delivered magma to the vent (Figure 7a). We note that this is our preferred interpretation of the AMS data and alternative interpretations are possible.

[27] In the north, magnetic lineations generally plunge steeply away from the vent area and become shallower to the north. Following an eruption, the magma drained away from the vent conduit as magma pressure in the igneous body at depth decreased allowing shallow magma flow to the north (Figure 7b). Just east of the vent, three sites yield steep magnetic foliations that likely experienced a strong degree of magmatic strain as the magma drained from the vent conduit. This is reflected in the strongly oblate susceptibility ellipsoids (Table 1). Once clear of the vent area the magma experienced a reduced flattening strain reflected by the progressive decrease in T away from the vent (Table 1, sites PP4, PP5, and PP6) yet the fabrics remain oblate. The oblate fabrics in these sites remain steep reflecting draining of the conduit back into the main body of the intrusion at depth (Figure 7b). Moving north, the magnetic fabrics are dominantly prolate reflecting a degree of magmatic strain dominated by stretching and little flattening associated with emplacement. The magma was thus more likely to flow unrestricted allowing the linear elements of the fabric to develop with orientations that are generally consistent across the northern part of the intrusion. We interpret the flow pattern in the north to reflect subhorizontal flow of magma filling a tabular sheet associated with the propagation of the intrusion to the north. It is important to note that the AMS fabrics record the last increment of magmatic strain (finite strain). Therefore, only a minor amount of sagging (magmatic flow) within the intrusion is required to generate the observed fabrics. It is therefore reasonable to interpret the consistent AMS fabric data as recording the last increment of strain related to magma flow and in this case reflecting flow away from the Pinto Peak vent area.

(Figure 7)

[28] In the southern part of the intrusion, the magnetic fabrics plunges/dips are steep to subvertical with no preferred strike/trend. We argue that the southern part of the intrusion represents the ascent site of the magma from depth (Figure 7a). In this scenario, magma ascended from depth along a steep feeder system to shallow crustal levels. Once at shallow depths, the magma lifted the overlying county rocks leading to a weakened roof and the formation of a focused network of fractures. Eventually, the magma forced its way upward through the network of fractures with an incipient vent developing. At or shortly after the magma reached the incipient vent, the overlying country rocks became unstable resulting in gravitational collapse of the roof releasing a gravity slide mass (Figure 7b). The rapid decrease in pressure led to explosive decompression of the magma chamber resulting in a pyroclastic eruption that deposited the Rock of Paradise ash flow tuff. Following the main pyroclastic eruption, effusive eruptions spilled from the vent flooding lava to the east covering part of the gravity slide mass.

[29] The magnetic fabrics in the conduit rocks are difficult to interpret largely because we have only data from seven sites in these rocks and the timing of fabric formation is difficult to constrain. Nonetheless, we offer a tentative interpretation of the vent facies data. The oblate magnetic fabrics in the vent area likely represent flattening against the conduit walls. This is further supported by the weak planar flow foliation observed in the vent conduit rocks. The variation in the strike and dip of the magmatic fabric likely records the site’s proximity to the wall of the vent. Near the central part of the conduit, subvertical AMS fabrics and weak magmatic flow banding are interpreted to reflect draining of the magma out of the vent while sites away from the central vent edifice likely preserve a local flow regime associated with flattening near the margins or roof of the vent.

4. Conclusions
[30] The Pinto Peak intrusion provides insight into the evolution of a relatively small intrusive—extrusive volcanic system. The system is highly unusual in that the country rocks show no deformation associated with the emplacement of magma to shallow depths that led to a gravity slide off the roof of the intrusion leading to an explosive eruption. Rock magnetic and remanence studies indicate that the AMS fabrics are carried by multidomain titanomagnetite grains that vary in composition spatially across the intrusion. The intrusion is a porphyritic andesite and the silicate and oxide minerals do not typically show planar or linear fabrics in the field or in thin section. The results from the AMS study map out a sequence of events from steep magma ascent from depth to a shallow crustal level as defined by magmatic fabrics in the southern part of the intrusion. Following eruption triggered by the gravity slide, the magma drained away from the vent area with subhorizontal magma flow as defined by the magnetic fabrics located in the northern part of the intrusion. The deceptively simple outcrop pattern of the Pinto Peak intrusion hides a more complex magma flow and emplacement history as evidenced by the results of this study.

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Where the Rocks of Paradise are found:

Where the ash went:



The rocks of Paradise tuff directly underlie the Rencher Formation and overlie the Harmony Hills Tuff.

Rock Abbreviations from youngest to oldest:
Tpvr, Rencher Peak flow member of Pine Valley Latite ;
Tpr, Page Ranch formation;

Tpv, Vent sequence of Rocks of Paradise;
Tplu, Upper lava flow member of Rocks of Paradise;
Tpll, Lower lava flow member of Rocks of Paradise;
Tpt, Ash flow tuff member of Rocks of Paradise;
Tar, Allochthonous rocks of gravity slide mass;
Tipp, Pinto Peak intrusion;

Th, Harmony Hills Tuff;
Tccb, Bauers Tuff member of Condor Canyon formation;
Tl, Leach Canyon formation;
TI, Isom formation;
Tc, Claron formation;
and Ki, Cretaceous Iron Springs formation.

Tgb Gravity-slide breccia (lower Miocene) – Moderately resistant, mostly pink and gray, tectonic breccia resulting from gravity slides (huge landslides) of various ages, made up of sedimentary (Tc) and volcanic (Tpv, Tcv, Tre, Tpa, Tqh, Ta, Tqc, Tql, Ti, Tw) rocks shed off the roofs of rapidly rising quartz monzonite porphyry laccoliths and stocks (Tipv, Tib, Tih, Tibm, and several others outside the map area) of the Iron Axis (Cook, 1957; Blank, 1959, 1993; Mackin, 1960; Blank and Mackin, 1967; Blank and others, 1992; Hacker and others, 1996, 2002; Hacker, 1998); maximum thickness in the mapped area about 250 feet (75 m).

22MA - Tpa - Rocks of Paradise (lower Miocene) – Resistant to moderately resistant, gray, pink, and red, crystal-rich, dacitic lava flows and poorly to moderately welded ash-flow tuff derived from eruption of the Pinto Peak intrusion, located just north of the map area, and tilted westward by emplacement of the Stoddard Mountain intrusion, also just north of the map area (Hacker, 1998; Hacker and others, 2002); 40Ar/39Ar ages are 21.97 + 0.09, 21.62 + 0.08, and 21.75 + 0.30 Ma on two samples (Rowley and others, 2006), in good agreement with the age of the Pinto Peak intrusion (21.96 + 0.11 Ma; UGS and NMGRL, 2007a); maximum thickness about 600 feet (180 m).


The BIG Picture:





NOTE: The 600 feet thick Rocks of Paradise were covered by 1,600 feet of Rencher Tuff.

Enlarged around Pinto and Pinto Peak. You are looking for the areas Identified as "Tpa" (some look like Toa) - there is one in the upper left hand corner by the powerline and Tqh; and looking for the gravity slide areas - "Tgb" - crosshatched.

A larger area. Note the slide area East of Stoddard Mountain!

The area most people know about was worked by the Spaniards as a Gold Mine.

Few know of any other location than the one known as "the Parking Lot" (yellow pin).

The Gravity Slide Areas were caused by the rising Laccoliths - Pine Valley, Cove Mountain, Stoddard Mountain, Iron Mountain, Three Peaks, etc.

And call the material "Holt Canyon Agate."


Looking at the area from the east.










There are pieces of the Rocks of Paradise all over the ground