Hurricane Airport Canyon, or Frog Hollow
Five kilometers south of the town of Hurricane, the local airport is located within a half km. of Frog Hollow- a canyon which can be hiked for a few hundred meters (before reaching a dead end box canyon). This location is shown in the following Google Earth photo:
Hiking to the box from the airport road side of Hf:
The Hurricane fault, Hf, traces NNE-SSW in this area, similar to the fracture pattern noted on the Colorado Plateau, CP, side of Hf. The airport is on level land- Basin and Range, B&R, with eroded Mesozoic rock, while CP exhibits Paleozoic limestones. The scarp between these is about 200 meters in height, not representative of Hf to the north of Laverkin- which may reach 300 meters. As may be seen in the photo, the canyons are arcuate, or circular as is common for Coriolis-influenced shear about Hf. I have explained this as due to CP moving CCW (rising)- which would be to the south on the high side of the scarp. Since there is a differential in movement on the two sides of Hf, the Coriolis effect causes a movement to the right- that is, a CCW portrait of the canyon (the same CCW rotation as CP). This might be considered a reactionary cell, RC, where the rock uphill merely rotates in reaction to the drag of Hf (in harmony with the rotation of CP- creating NO HEAT SUFFICIENT FOR VULCANISM). We will check any seeps found to see whether there is a temperature rise due to BRITTLE ROCK FRICTION. This may be compared to weather cells, in this case to HIGH PRESSURE CELLS OF FAIR SKIES, where the high pressured air move outwardly and when moving to the right creates a CW Cell. THE CW MOVEMENT IS A SINKING FEATURE- WHICH CREATES CLEAR SKIES, BY COMPRESSION (IN CONTRAST TO A RISING FEATURE, CCW, OR LOW PRESSURE WITH BAD WEATHER) Think of the rock as rising (above the Hurricane Valley,) which is moved to the right- hence making a CCW trace as it encircles the upwardly-moving segment of crust.
Below is a traverse made on top of the TOPOGRAPHY- A DISTANCE OF 3/4 KM:
The feature, which we will investigate further, is the ellipse which lies within the cell of ¾ km diameter. I have found that larger features iminging on other larger ones tend to form an ellipse when constrained by the two features. In this case, it appears that the ellipse is dominated by the local fracture pattern, but field evidence may shed some light on the dynamics of this secondary feature. We will measure seep temperature, fracture and fault orientation, dips, and tilt of the entire feature, and this may require a hike above Hf as well as into the canyon. We will seek slickensides to authenticate the direction of lateral faulting, and get photos of unusual anomalies.
After hiking Frog Hollow again, some photos of anomalies are shown below:
TRAVERTINE IS FORMED AS FOLLOWS: SURROUNDING LIMESTONE BEDS SUBJECT TO SHEAR PRESSURE OF ROTATING CELLS DISSOLVES (SOLUBILITY INCREASES WITH INCREASING PRESSURE AND LOWERING TEMPERATURE). WHEN AN OPENING OR VUG IS ENCOUNTERED, THE PRESSURE DROPS AND THE DISSOLVED IONS DROP OUT AS TRAVERTINE. THIS IS A FIRST STEP IN FORMING SLICKENSIDES, EXCEPT THAT SILICA MUST BE DISSOLVED WITH INCREASING PRESSURE. TEMPERATURE IS A FACTOR, BUT THE DOMINATING FACTOR IN THE P, c, T SYSTEM IS P. COMPOSITION MAY ALSO CHANGE, AND FOR SILICA VERSUS DISSOLVED LIME, THE SILICA REPLACES THE LIMESTONE AS PRESSURE DROPS- FORMING A SILICATE HARD-FACE ON THE LIMESTONE.Below is a photo of the area analyzed further:
A hike to the east side of Hf yielded a box canyon, below which we could not descend. There is an excellent half-spiral in the Frog wash, with obvious spalling on the north side, rotating CW (a sink), and with measurable dip and tilt to the Coriolis cell. The general dip of sedimentary beds is toward the Virgin river to the north about 2 degrees, but the local basalt found in the Frog Hollow has flowed in the opposite direction- to the south, terminating in the walls of the wash.
GOULD'S WASH- CANYON TO NORTH OF FROG HOLLOW
NEXT WE WILL EXPLORE THE CANYON TO THE NORTH OF FROG HOLLOW, STARTING WITH THE ENTRY INTO THE VIRGIN RIVER- JUST NORTH OF THE SKY MOUNTAIN GOLF CURSE IN HURRICANE. THEN WE WILL PROCEED UPSTREAM TO NOTE THE BASALT WALLS AND THE TURN TO THE RIGHT TOWARDS THE HURRICANE CLIFFS- WHERE IT FORMS A BOX CANYON:
NEXT IS A HIKE INTO GOULD'S CANYON ON THE UPSIDE OF Hf:
LOOKING TO THE SOUTH OF GOULD'S, THERE IS A BASALTIC PLATEAU WHICH YIELDS THE FLOW ENTERING FROG HOLLOW- FROM THE SOUTH?
I HAD THOUGHT THAT GOULD'S WASH AND FROG HOLLOW WERE PART OF THE GRASS VALLEY CELL (since they were within the 30 km configuration); HOWEVER, THEIR CELLS EXIST EAST OF Hf, AND THEY ARE SEPARATE, AS SHOWN BY THE FOLLOWING TWO DIAGRAMS:
YOU CAN SEE THAT THERE ARE FOUR CANYONS, INCLUDING THE FORT PIERCE WASH, BUT FROG HOLLOW AND GOULD'S WASH ARE NOT PART; WE MUST DETERMINE WHAT IS THE VULCANISM ASSOCIATED WITH THEIR ROTATION.
NOTE THAT THERE IS NO BASALT RIM SOUTH OF GOULD'S, BUT IT IS PLENTIFUL AS A RIM TO THE NORTH. FURTHER, THE CIRCULAR FEATURE IS ENTIRELY ON THE EAST SIDE OF Hf.THIS MEANS THAT THE CELL IS A REACTIONARY CELL (DRAG) AND NOT FORMED BY VULCANISM:
THE LARGER VIEW SHOWS GOOSEBERRY MESA TO THE EAST, WHICH WE WILL HIKE THIS SPRING: 
TO BE CONTINUED, WITH HIKING AND FURTHER ANALYSIS OF THE ANOMALY.
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