GEOLOGY OF THE MURPHY AREA
Dating the age of the earth
The universe is about 15 billion years old, the earth about 4.6 billion years. The oldest rocks in North Carolina have been dated to 1.8 billion years ago (bya). Most meteorites found in the solar system date to 4.56 bya, and zircons from western Australia have been dated to 4.3 bya.
The half life of uranium (U238) is 4.47 billion years. As it decays by fission, the daughter atoms shoot away from each other producing tracks on adjacent mineral surfaces; thus, the rate of track formation will be proportional to the rate of decay of the uranium. If such a mineral is reheated by a geological event, the tracks disappear, thus resetting the clock to date that newer event.
Radioactive dating of Appalachian rocks is done by measuring the radiation from zircon crystals.
Before the mountains
During the last billion years, continents have moved at a rate of 1” to 8” per year; oceans have formed and disappeared; and mountains have risen and worn away. The fastest movement was the collision of the Indian sub-continent which subducted under the Eurasian continent 50 million years ago, producing the Himalayan Mountains.
The original sediment for the Great Smokies was deposited on a delta or alluvial coastal plain; seaward of this deposition was a lagoon or tidal flat behind a barrier bar. Silt (now slate and phyllite) was deposited in the lagoon, and sand (now quartzite and metasandstone) formed the barrier bar.
Further seaward was a broad ocean shelf, collecting the sediment that would become the schist of the Brasstown Formation. Then widespread environmental changes laid down the limestone that would become the Murphy marble, followed by another change in composition which would form the present Andrews schist. A final change resulted in the sediment that would form the Nottely quartzite and Mineral Bluff formations.
Plate Tectonics: Appalachian Orogeny (animation: http://www.scotese.com)
1 billion years ago, the South American continent collided with North America, forming the super continent of Rodinia and metamorphosing the rocks of the northeast coast.
750 million years ago, the South and North American continents separated, allowing stream erosion into the ocean to form a six-mile-thick bed of alternating layers of sand, clay, and gravel which would harden into sandstone, shale, limestone, and conglomerate.
570 million years ago, a chain of volcanic islands collided with North America, causing huge crustal uplifts along thrust faults.
450 million years ago, the east coast marine shelf was subducted under the Atlantic plate, consuming most of the marine sediment and ocean crust between the European/African and North American continents. The Carolina Terrain magmatic arch collided with the edge of the continent, depositing exotic fossils. Huge sheets of ocean-floor sediments were thrust upward and westward along the continental coast, forming the prototype Appalachian Mountains.
270 million years ago, the African tectonic plate (Gondwana) collided with the North American east coast at 4 inches per year, forming the Pangaea super continent, compressing and folding the eastern edge of the North American plate to 50% of its original breadth and metamorphosing the sediments. Folding occurred at all scales, from microscopic to regional.
The frictional pressure turned the ocean’s waters into steam and made rock ductile. Sandstone was fused into metasandstone and quartzite, shale into slate, and limestone into marble. More important, the bedrock thrust upward, finalizing the formation of the Appalachian Mountains. Stretching 1600 miles from Alabama to Newfoundland, then becoming part of a chain through Scotland and Norway, the Appalachians are now mere eroded plateaus of the original peaks which were as high as the Andes. At an erosion rate of about 1 millimeter per year, wind and water carried the sediment which is now seen as the sands of Florida, southern Georgia, Alabama and coastal North Carolina, where it reaches of depth of 10,000 feet under Cape Hatteras.
250 million years ago, violent volcanic eruptions caused global warming leading to the extinction of 90% of the species of life.
200 million years ago (Mesozoic era): Pangaea began to break up as the North American and the European/African continents separated, forming the Atlantic Ocean which continues to widen today, forming the mid-Atlantic ridge.
100 million years ago (Cenozoic Era): Regional uplift rejuvenated the streams; flowing waters began eroding the mountains, forming the Ocoee and Nantahala River gorges. As boulders tumbled down streams they were progressively reduced to cobbles, pebbles, sand, and silt. The lower bedrock is covered by thick deposits of weathered rock and clay. The process continues at the same rate today, but our limited lifetime perceives the landscape as permanent.
Over the next 200 million years, the continents will again merge into a giant super continent.
The Rocky Mountains were formed by earthquakes and imbalances in the plate. Uplifts were joined by volcanic eruptions which fused additional minerals into the mix. New fissures from the disturband created the New Madrid fault, forming the Mississippi River basin.
The Murphy belt is an irregular, northeast-southwest-trending structure, stretching 100 miles from Cartersville, GA to Bryson City, NC, and sits between the Unaka range on the west and the Blue Ridge range on the east. It is almost entirely metasedimentary rock.
The doubly-plunging “Murphy syncline” basin is actually a synclinorium, an isoclinal (parallel-limb) fold, recumbent (overturned) 60 degrees to the northwest, the result of four separate folding events:
F1 (Murphy Phase, 470 million years ago): Initial sharp folds forming nearly-parallel limbs produced the Murphy syncline.
F2 (Hanging Dog Phase, 450 million years ago): A thermal peak of metamorphism folded the syncline a second time, producing an antiform and a synform (which may reverse the apparent ages of the layers), seen on the northwest side of the Murphy Belt as a regional bedding dip.
F3 (Martin’s Creek Phase, 400 million years ago): Regional cooling reversed the metamorphism slightly, producing southeast-dipping cleavage on the northwest side of the Murphy Belt.
F4 (Marble Phase, 350 million years ago): A gentle warping of the previous folding produced no additional metamorphism. Dipping northwest, the effects of F4 are visible northeastward between Marble and Andrews where the recumbent F3 folds are nearly horizontal.
MINERAL BLUFF GROUP (After Thompson and Tull, 1991; Aylor 1994)
Peachtree Creek Formation (1500 feet thick)
This youngest, topmost unit of the group consists of very-thinly-layered metapelite and metagraywacke containing grains of quartz, feldspar, chlorite, mica, epidote, amphibole, and garnet. At the base it is interlayered with Harshaw Bottom quartzite.
Type section may be seen at low water levels in the Hiwassee River from 0.25 mile south of McComb Branch through Peachtree Creek, and on the north face of a ridge 650 feet west of the McComb Branch/Hiwassee River confluence.
Harshaw Bottom Quartzite Formation (300 feet thick)
This most distinctive formation consists of very-fine-grain, massive, high-purity (97+%), white quartzite rich in epidote, with some chlorite and muscovite. Usually massive, occasionally layered and crumbly/papery when weathered. A type section is an abandoned quarry on the hilltop at the intersection of U.S. 64 and Hendrix Road. Here the bedding is interlayered with the overlying Peachtree Creek Formation. A small exposure is seen at the hillside of U.S. 64, approximately 200 feet north of Hendrix Rd.
Fort Butler Mountain Formation (2300 feet thick)
These exposures hold up numerous mountains along US 74/19/129 from Ranger to Andrews. The huge slabs of silver-gray phyllite meet massive, fine-grained muscovite metaclay. This sandy, graphite-bearing, turbidite sequence is interbedded with metasandstone and metaconglomerate from 1” to 6’ thick, and contains quartz, feldspar, muscovite, biotite, and some chlorite and hematite. Coarse clastic intervals up to 200’ thick include chert, muscovite, metasandstone, metaclay, blue quartzite, and feldspar.
Excellent exposures form dip slopes along US Highway 64 (River Road) from north of Hendrix Road to the new bridge.
Mission Mountain Formation (2900 feet thick; appears as a massive, brown wall)
This mineral-diverse formation is characterized by a grayish-green turbidite sequence of thinly laminated (0.5”-2’) metagraywacke.
The Andrews unit consists of paper-thin to several-feet-thick layers of greenish-gray to dark blue-gray, cross-biotite schist with hematite, interbedded with impure marble containing mica and pyrite. Saprolites may be seen as layers of alternating red, yellow, blue, and purple clay. Layers and concretions of iron oxide remain from nearly a century of mining through WWI; nearby pits are still evident.
The Nottely quartzite unit near the base consists of cross-bedded, fine- to medium-grained metasandstone 150’ thick, containing muscovite and traces of tourmaline, hematite, and slate. It may be seen at the Valley River and Hiwassee River confluence, comprising two sections separated by mica schist totaling 180 feet in thickness, forming a nearly-continuous outcrop belt from Mineral Bluff to Tomotla.
Excellent exposures are on old SR 64 at the Hiwassee River/Brasstown Creek confluence, 0.1 miles either side of the intersection of US 74/19/129 and Regal Rd., and on the north side of Mission Mountain in Peachtree.
HIWASSEE RIVER GROUP (After Thompson and Tull, 1991; Aylor, 1994)
Murphy Marble Formation (300 feet thick)
This most distinctive formation of all consists of impure calcareous (calcium carbonate) and dolomitic (magnesium carbonate), bluish-gray, light gray and white marble. Associated minerals include talc (found only as pods and deposits in the center of white marble), graphite, biotite, amphibolite, and pyrite. At its base, just before contact with the Brasstown formation, coarse brown mica is abundant in the marble.
Marble exposures are rare because of rapid weathering, but do appear in valleys and stream cuts from Ball Ground, GA to Topton, NC.
Brasstown Formation (1600-8300 feet thick)
This thin-bedded, alternating sequence is made up of light-gray metasandstone containing quartz, muscovite, feldspar, and minor hornblende and garnet; dark-gray metasiltstone containing biotite and minor graphite; and coarsely-schistose mica schist. Grain-sized pockets of garnet and biotite are scattered, as are some slatey layers. Half-inch banding is fairly straight and continuous.
Lower layers of micaceous metasiltstone split easily along fine muscovite cleavage planes, leaving a silky sheen. At the lowest level are brownish-gray phyllite with muscovite, biotite, quartz, feldspar, and minor graphite, and metasiltstone.
Excellent exposures are seen on both sides of the Hiwassee River west of Murphy.
Nantahala Formation (5200 feet thick)
Tan to white metasandstone (formerly “Tusquitee quartzite”) is interlayered with dominant dark, laminated metasiltstone (“black slate”) and displays a wavy, ripple-drift character for several feet. Alternating, half-inch bands of tan to white quartz metasiltstone contain minor feldspar, graphite, and biotite, and darker metapelite with grain-size biotite, muscovite, graphite, pyrrhotite and some garnet.
Its slate-like character exhibits original bedding planes, but low mica content prevents clean cleavage. Some garnet may be present.
Exposures are commonly iron-stained and covered by yellow or white gypsum encrustations. A bottom layer of biotite schist separates this formation from the Great Smoky Group.
Excellent exposures are seen in the Hiwassee River banks west of Murphy and in the Hanging Dog quarry (Joe Brown Hwy.).
GREAT SMOKY GROUP (After Thompson and Tull, 1991)
Dean Formation (1000 feet thick)
The upper layer displays interbedded garnet, staurolite, mica schist; metagreywacke, and metaconglomerate (specimens found 3-1/2 miles north of Murphy out Joe Brown Highway, just past the Hanging Dog Bridge, below the dumpsters.
Well before the first Europeans entered the region, native Americans utilized mica, soapstone, hematite, quartz, and rhyolite to fashion into ornaments, utensils and tools. The Nation’s first gold rush took place near Charlotte in 1799 after the discovery of a large nugget, and gemstones like ruby, sapphire and emerald are regularly found.
Marble was mined continuously for more than a century in at least 8 quarries. 4’ x 4’ x 8’ blocks were first drilled all around by parallel drill holes separated by one inch, then broken away by leverage and transported by rail to Regal Quarry for processing to dimension stone. Waste blocks were piled to the side because of chips, cracks, impurities, or other defects, and are still there. Marble and talc mining became unprofitable due to outside competition. The Murphy talc mine was closed in 1979, and the marble quarries closed in 1981.
Most of the local rock is crushed for road gravel and rip-rap for erosion control.
Feldspar weathers rapidly. Pioneers used the feldspathic metasandstone of the Nantahala formation as an abrasive to clean wood floors.
Wedgwood china agents traded with the Cherokee Indians for kaolin clay in Clay County, and Tiffany jewelers mined gem stones in Macon County.
The giant mirror in the Palomar telescope was made from pure North Carolina quartz.
Copper Basin was the largest metal mining operation in the southeast from its opening in 1850 until 1900. The 50 square miles of barren landscape was caused by a combination of tree cutting to fuel the smelters, and toxic sulfur dioxide fumes from the process. The collapse of the Burra Burra Mine in 1959 was barely audible to the miners working 2000’ below, and there were no injuries. The mines closed in 1987 and were bankrupt by 1989. If it becomes economically feasible to reopen the mines, there is enough documented ore for at least 15 more years of production, but it would take three years to pump the water out of the shafts and meet EPA regulations. Many locals resent the reforestation of the barren landscape.
GLOSSARY OF GEOLOGIC TERMS
Anticline: Upward fold of stratified rock.
Calcareous: containing calcium carbonate (limestone, marble).
Clastic: Composed of rock fragments (clasts):
Clay (forms mudstone or shale, also called argillite; said to be “pelitic”): Feels smooth, doesn’t taste gritty.
Silt (forms siltstone): Slight abrasive feel and gritty taste (don’t make a habit of chewing it!)
Sand (forms sandstone): Grains small but visible without magnification.
Pebble: You can easily throw it far.
Cobble: You can pick it up and carry it, but can’t throw it very far.
Rip-rap: Crushed rock used in layers for erosion control.
Boulder: You can’t even pick it up.
Detritus: Loose rock material worn off by mechanical means; sand, silt, clay, etc.
Saprolite: Earthy, thoroughly weathered rock
Float: Rocks weathered loose from their bedrock, often found far from their origin.
Cleavage: The tendency of a foliated (banded, layered, bedded) rock to separate along planes of weakness, usually mica.
Fissile: Finely layered; easily split into thin laminations (e.g., shale, phyllite or slate).
Schistose: Coarse-grained, crystalline layers
Gneissic: Crudely layered, often discontinuous
Crenulated: Wavy, undulated layering in a rock, typically under an inch length; folding is much larger scale.
Foliated: Banding or layering from parallel mineral alignment; grain may be finely plated (fissile) as in slate and phyllite, medium plated as in schist, or coarse as in gneiss.
Confluence: The merging of two streams of water.
Crystal: A homogeneous, repeating structure with plane faces. Crystals grow only a few atomic diameters per year, approximately one millionth as fast as a tree; thus, a typical crystal might take 20-30 million years to grow.
Detritus: Loose rock material worn off by abrasion; sand, silt, clay, etc.
Saprolite: "Rotten" rock, often decomposed, crumbly feldspar. It may retain original its rock structure until easily crushed. It is intermediate between rock and soil.
Dike: Sheet of rock formed by melt-cutting angularly through layers of existing rock.
Sill: Sheet of rock forced, when molten, between existing rock layers.
Dip: The angle that the plane of a rock bed makes with the true horizontal reference.
Strike: The compass bearing of the plane of a rock bed as it intersects the horizontal surface plane.
Evaporite: A deposit formed by the evaporation of water (e.g., halite, gypsum).
Fumarole: A volcanic vent often rich in sulfurous gasses which may deposit sulfur.
Igneous: Rock formed from cooled magma.
Sedimentary: Rock produced from particles transported and deposited by wind, water, gravity, or ice, with subsequent pressure. Examples: Sandstone, siltstone, shale, conglomerate, limestone.
Metamorphic: A former igneous or sedimentary rock changed through heat and pressure.
Isoclinal folding: Limbs (sides) of the fold are nearly parallel.
Isostasy: Flotational balance of the lithosphere (crust) on the aesthenosphere (plastic upper mantle).
Lava: Molten rock, formerly magma, escaping from a volcano.
Magma: Molten rock from the earth’s mantle; ascends through the earth’s crust by:
Intrusion (dikes and sills)
Diapiric rise (melts massively and progressively upward)
Assimilation (digests surrounding rock progressively upward)
Meta-: Prefix for “metamorphic,” attached to protolith name. Fractures usually break through, rather than around, the particles due to their fusion during metamorphism.
Limestone (calcareous and dolomitic from shells) > marble
Sandstone > metasandstone (non-crystalline grains still visible, often varicolored, but fracture rather than crumble) > quartzite (grains fuse into one mass, no longer visible, although phantom outlines may remain under magnification)
Shale (laminated claystone or mudstone) > slate (metasiltstone in which some clay has converted to mica layers) > phyllite (even more mica has formed, producing silky, crenulated cleavage planes) > schist (dominant mica formation, coarse grained, foliated; often contains crystals of garnet, staurolite, kyanite) > gneiss (from sedimentary or granitic igneous protolith; gray to white, always banded and often distorted by alternating light-colored quartz and feldspar separated by layers of mica; coarsely schistose. Resembles granite except for layered mica.
Note: Grains can grow during metamorphosis; metasiltstone can look like metasandstone. Metaconglomerate contains squeezed, flattened and aligned pebbles. Metasedimentary rocks preserve the original banding of their sedimentary deposits. Migmatite is a rock partially metamorphosed and partially igneous from subduction reheating.
Mineral: A natural, inorganic substance having a uniform chemical composition (i.e., quartz, corundum)
Rock: An aggregate of minerals (i.e., granite, sandstone).
Orogeny: Mountain forming by thrust, faulting, and folding.
Protolith: The original rock form before metamorphosis.
Pyroclastic: Rock formed by volcanic explosion
Schistose: The ability of a rock to be split into thin layers.
Sorting (grading): The separation and gradation of sediment by specific gravity, size or shape by stream action. Stream action also produces rounding, compaction and lithification with depth, as well as cross-bedding.
Syncline: A large, downward fold of rock.
Synclinorium: A large basin with exhibiting minor folds.
Turbidite: Sedimentary deposit showing preserved ripple marks of water currents; often displays graded bedding.
GLOSSARY OF LOCAL ROCKS AND MINERALS
Amphibole: A cluster of elongated crystals intersecting at two angles; often hornblende or tremolite/actinolite
Actinolite: Green, fibrous crystals; an asbestos
Amphibolite: Black hornblende; basalt protolith
Picrolite: Columnar fibers
Serpentine: Silky, waxy crystals
Smaragdite: light green, thinly-banded
Tremolite: White crystals; an asbestos
Chlorite: Green or black, flat crystals resembling inflexible mica.
Conglomerate: Sandstone or siltstone containing rounded pebbles; called puddingstone (British) or pebblestone if pebbles are very prominent; or breccia if pebbles are sharply-angled; or graywacke if sharply-angled quartz and feldspar pebbles are in a dark, coarse-grained sandstone or siltstone.
Corundum: Extremely hard aluminum oxide mineral; rich red called ruby, blue called sapphire.
Dolomite: Magnesium-rich limestone.
Epidote: Yellow to green long, grooved prisms, or thin crusts of smaller crystals; often associated with marble.
Feldspar: Opaque mineral with two right-angle cleavages, the most abundant mineral (60%) in the earth’s crust.
Orthoclase (white, gray, pink; monoclinic)
Plagioclase (triclinic; albite is white or colorless, striped variety)
Microcline (white, gray, brick-red, green; triclinic with colored stripes)
Garnet: A dark red (almandine) to brownish crystal commonly found in mica schists, olivine, and peridotite.
Gypsum: White, hydrous calcium sulfate; often forms as a crust on weathered rock.
Hematite: Red, earthy (“paint ore”); or black, metallic appearance; leaves dark red streak.
Hornblende: Black, thin, prismatic crystals.
Kaolinite: White clay rock; crumbles easily. Used for porcelain.
Kyanite: Blue-bladed crystals imbedded in rock; or long, slender, brown, green or white, parallel bundles (sillimanite).
Limonite: Brown mineral formed by the oxidation/weathering of iron-bearing minerals.
Marble: Metamorphosed, granular limestone. Hydrochloric acid causes dolomitic marble to bubble moderately, but calcareous marble bubbles vigorously.
Mica: Black (biotite) or white to pale brown (muscovite), platy mineral that easily separates into flakes.
Olivine: Massive, green (gray, brown) crystalline rock often containing garnet. If silky or waxy, called serpentine.
Peridotite: Massive, dark-mineral rock often containing garnets; may contain olivine, then called dunite.
Pyrite: Iron sulfide, “fool’s gold,” iron pyrites; brassy, cubic, sometimes massive, crystals.
Pyrrhotite: A brown, hexagonal-crystal, iron sulfide.
Quartz: A highly diversified mineral group based on SiO2; glassy rock; clear or cloudy; white or colored; crystalline or massive. A source of semi-precious gemstones like amethyst, citrine, rose quartz, rutilated quartz, agate, jasper, obsidian.
Quartzite: Metamorphic, massive, quartz sandstone (metaquartzite, metasandstone).
Rutile: Needle- or hair-like golden or reddish-brown crystals, or larger black, flat crystals.
Silicate: The largest mineral group, composed of silicon oxides.
Spinel: Pyramid- or triangle-shaped black, green, red, blue, violet, brown, or white crystals; may also be embedded, coarse grains. Often associated with corundum.
Staurolite: Brown, prismatic, six-sided crystals or “fairy crosses”—crystals intersect at 90 or 60 degrees.
Talc: Soapstone; white or greenish-white, fibrous rock with a slippery feel, soft enough to be easily scratched with a fingernail. Used for talcum powder and carving.
Zoisite: Slender, grooved, green prismatic crystals, sometimes massive.
Chemical tests (effervescence in hydrochloric acid)
Optical properties (translucency, transparency, opaqueness, refraction)
Crystal form (cubic, tetragonal, hexagonal, orthorhombic, monoclinic, triclinic)
Hardness (Mohs’ scale) (Absolute scale)
(1) Talc 0.03
(2) Gypsum 1.25
(3) Calcite 4.5
(4) Fluorite 5
(5) Apatite (Knife blade) 6.5
(6) Orthoclase 37
(7) Quartz 120
(8) Topaz 175
(9) Corundum 1000
(10) Diamond 140,000
Specific gravity (weight compared to equal volume of water)
2.6-2.8 (Non-metallic); 5+ (Metallic)
Color (surface color under natural light
Color play (iridescence; labradorite and opal)
Cleavage (Breaks revealing a flat surface; may be perfect, good, fair, poor)
Habit (Crystal shape)
Equant (facets similar in all directions; garnet)
Tabular (length in one direction greater than the other)
Bladed (one long direction like the blade of a knife)
Prismatic (Elongated, but not flattened)
Crystal cluster types
Dendritic (divergent branches)
Radiant (radial pattern)
Drusy (Surface covered with a layer of small crystals
Fibrous (Individual fibers; asbestos)
Colloform (spherical mass)
Twinning (in pairs)
Contact twins (crystals angle away from each other)
Penetration twins (crystal bodies merge)
Cleavage (breaks along a flat surface) or no cleavage
Conchoidal (rounded chips--quartz)
Striated (long, parallel lines due to zoning or growth stages)
Luster (appearance of reflected light)
Streak (Color when pulverized by rubbing against a rough ceramic plate)
Fluorescence (glows under UV light)
Magnetism (strongly magnetic, magnetite; weakly magnetic, pyrrhotite)
CLEANING ROCKS AND MINERALS
After you shape the rock into the appropriate size for exhibit, it is a good idea to clean it of its surface soil. Scrub with a stiff-bristled brush using warm water and dishwashing detergent. If that isn’t enough, try a half-hour soak in a 4:1 mix of water and ammonia with a squirt of dishwashing detergent, then scrub again to remove loosened particles.
Surface stains may be removed with a 2:1 dilution of muriatic (hydrochloric) acid. Use rubber gloves and plenty of air circulation!
It’s not gneiss to be taken for granite
I never metasandstone that I didn’t like
I dig rocks
Geologists have their faults
Geologists are down to earth
Geologists graduate magma cum laude
Kiss a geologist and feel the earthquake
May the quartz be with you!
A man goes into a specialty restaurant and starts reading the menu: Broiled Accountant $5.95; Fried Engineer $7.95; Grilled Geologist $24.95. He asks the waiter, "Why does the Grilled Geologist cost so much more?" The waiter answers, "Are you kidding? Do you know how hard it is to clean one?"
Geologists are amazing--they know hundreds of words for dirt, and hundreds more for things dirt does when left alone for a few million years.
A geologist was talking to a group of elementary school teachers, observing how kids are fascinated with dinosaurs and digging around for pretty rocks. So he asked the teachers why more of them didn’t become geologists. Their answer? Most kids grow up!
Books likely to remain on the library shelf:
Diastrophism for Dummies
101 Uses for Saprolitic Residue
Sedimentation and You
Adventures in Hillside Creep
So you want to be a Geostratigrapher?
Great Moments in Metamorphism
A Geologist Looks at Cleavage
The Heartbreak of Thunderclap
A Beginner’s Guide to Pelitic Rip-Rap
Unstable ground conditions, especially after the spring thaw or rain, make old rock walls and road banks hazardous. They become extremely dangerous during periods of alternate freezing and thawing which widen seams and cracks, weakening the banks. Overhanging ledges may fall without warning, injuring those on them as well as anyone below.
Waste blocks at quarries become more dangerous as the supporting fragments weather. Visually assess the stability of blocks and banks before approaching them. Stay away from old machinery and cabling. Stay within range of the group.
MOSQUITO & TICK REPELLANTS
Bounce Fabric Softener Sheets (wipe on)
One vitamin B-1 tablet a day (Thiamine Hydrochloride, 100 mg.)
Don’t eat bananas in the summer
Marigolds planted around the yard
Avon Skin-So-Soft bath oil mixed half and half with rubbing alcohol
Pure Vanilla (as sold in Mexico)
Safety goggles or eyeglasses
Gold pans, screens, vial or paper, buckets, shovel, magnet, boots
First aid kit
Geologist’s pick or brick (stonemason’s) hammer
White-Out, clear nail polish, fine-tip black marker
Plastic pail or basin for soaking specimens
Hair dryer for washed specimens
Stiff nylon brushes
Small cloth bags for collecting specimens