SPI Covers Arizona!
Sonoran Paranormal Investigations, Inc. provides investigative teams covering the entire state of Arizona with three cooperative teams located in Tucson, Phoenix, and the Verde Valley area. Members of SPI come from all areas of Arizona including but not limited to: Sierra Vista, Benson, Tucson, Casa Grande, Chandler, Phoenix, Flagstaff, Queen Creek, Show Low, Glendale, Camp Verde, Mesa, Globe, and Scottsdale.
Sonoran Paranormal Investigations, Inc. dedicates itself not only to individual investigations of claims of paranormal activity but is also among the handful of groups worldwide utilizing data obtained during investigations as part of long term studies. SPI believes that only through studying phenomena over long periods will it be possible to eventually craft legitimate theories of haunting phenomena. After each investigation all results from experiments and environmental readings are retained and analyzed whether regarded as "paranormal" or natural. Over time this data analysis will enable SPI to form sound theories and explanations for haunting phenomena as well as show trends influencing paranormal activity or perceptions of paranormal activity. Likewise, such in depth analysis will allow SPI to show existing ideas on paranormal activity, generally handed down as anecdotes, as either valid or invalid based upon true scientific inquiry and stringent analysis.
Unlike many groups in the field, SPI does not adhere to an "investigate and forget" mindset, but rather an investigate, correlate, analyze, and theorize mindset making SPI true members of the scientific community rather than hobbyists.
Charging for Investigations is Unethical!
SPI NEVER charges for a paranormal investigation! We at SPI use our own equipment, our own time, and make our own travel arrangements - this is all at our own expense. We do not accept outside donations. We do not perform cleansings or blessing but can direct clients to respectable spiritual or religious practitioners who may be able to assist them when necessary.
Choosing a Paranormal Investigator
For more information about how to choose a paranormal investigator,please read this article, written by Buck Bannister of "Buck's Ghosts & Hauntings" and a columnist for Unexplained Mysteries.
Taps Family Members
SPI - Arizona's Leading Paranormal Investigators!
Sonoran Paranormal Investigations (SPI) is a paranormal investigation group located in and serving the state of Arizona. We have members from Flagstaff to Tucson and we are able to meet the needs of families and businesses throughout the entire state.
In 2007, we were proud to become TAPS Family Members. You may be aware of TAPS (The Atlantic Paranormal Society) and TAPS Family from the Sci-Fi channel series Ghost Hunters.
Becoming involved with the TAPS Family not only ensures that we are doing the right thing - but it keeps us doing the right thing. The TAPS Family affiliation provides SPI and our clientele with access to some of the best and brightest in the field and ensures that we have access to the latest information and knowledge of the latest technology available.
Our unique approach to professional investigation has set SPI apart among investigative groups. We have been called in by homeowners and business owners but also by government agencies including historic sites, local and state government (including police), and the United States Army.
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We have had many offers from people with psychic type abilities to assist our team in different ways. While we appreciate the offers we do not use psychic type skills in any of our capacities. We do, however, have a few areas on our forums geared toward the psychic topics and welcome you to join us on our forums.
|Common Rocks of Arizona||| Print ||
|Friday, 22 August 2008 00:00|
Common Rocks of Arizona
By Jess Boatwright on August 22nd, 2008
The types of rock are broken into three categories: Igneous, Sedimentary, and Metamorphic. We will explore the most common of these found throughout the state of Arizona.
Igneous rocks (from the Greek word for fire) form from when hot, molten rock (magma) crystallizes and solidifies. The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface. Igneous rocks are divided into two groups, intrusive or extrusive, depending upon where the molten rock solidifies.
Intrusive Igneous Rocks
Intrusive, or plutonic igneous rock forms when magma is trapped deep inside the Earth. Great globs of molten rock rise toward the surface. Some of the magma may feed volcanoes on the Earth’s surface, but most remains trapped below, where it cools very slowly over many thousands or millions of years until it solidifies. Slow cooling means the individual mineral grains have a very long time to grow, so they grow to a relatively large size. Intrusive rocks have a coarse grained texture.
Extrusive Igneous Rocks
Extrusive, or volcanic, igneous rock is produced when magma exits and cools outside of, or very near the Earth’s surface. These are the rocks that form at erupting volcanoes and oozing fissures. The magma, called lava when molten rock erupts on the surface, cools and solidifies almost instantly when it is exposed to the relatively cool temperature of the atmosphere. Quick cooling means that mineral crystals don’t have much time to grow, so these rocks have a very fine-grained or even glassy texture. Hot gas bubbles are often trapped in the quenched lava, forming a bubbly, vesicular texture. Pumice, obsidian, and basalt are all extrusive igneous rocks.
Igneous Rock Classification
Igneous rocks are classified by the geologic environment where they formed from the crystallization of molten material, and perhaps more importantly, by their mineral composition. Intrusive igneous rocks (like granite or gabbro) typically display visible mineral grains that are fairly easy to recognize with a little training. Extrusive rocks are more difficult to clearly identify because the mineral grains are typically invisible. However, the general composition of an extrusive rock is reflected by its color and density characteristics. General composition types include felsic (which is a mnemonic word derived from “feldspar” and “silica”), and mafic (which means rich in magnesium and iron, Fe). Felsic rocks tend to be light colored (white, pink, yellow), and are typically much less dense than mafic rocks that are typically dark (gray, brown, or black).
Types of Rocks in Arizona:
Granite is an igneous rock that is composed of four minerals. These minerals are quartz, feldspar, mica, and usually hornblende. Granite forms as magma cools far under the earth’s surface. Because it hardens deep underground it cools very slowly. This allows crystals of the four minerals to grow large enough to be easily seen by the naked eye.
An intrusive igneous rock made of plagioclase feldspar and amphibole and/or pyroxene. Similar to gabbro only not as so dark, and containing less iron and magnesium.
Diorite is of intermediate composition. It is called “salt and pepper” rock because of its nearly equal proportions of light, felsic minerals (mostly plagioclase and quartz) and dark, mafic minerals (amphibole and biotite). Diorite is close in composition to granodiorite, and it requires fairly close inspection to differentiate the two rocks. Diorite typically contains no orthoclase feldspar (pink potassium feldspar).
Rhyolite is very closely related to granite. The difference is rhyolite has much finer crystals. These crystals are so small that they can not be seen by the naked eye. Rhyolite is an extrusive igneous rock having cooled much more rapidly than granite, giving it a glassy appearance.
Composition of Rhyolite
Rhyolite is a felsic (rich in silica and aluminum), rock, light gray, typically pink to red, fine-grained, sugary texture, usually has a brecciaed texture (tuff) and sometimes contains phenocrysts of feldspar (Na- rich varieties), quartz, hornblende, and biotite mica. Rhyolite’s silica (SiO2) content is greater than about 68 weight percent. Sodium and potassium oxides both can reach about 5 weight percent. Common mineral types include quartz, feldspar and biotite and are often found in a glassy matrix.
Pumice is a light, porous volcanic rock that forms during explosive eruptions. It resembles a sponge because it consists of a network of gas bubbles frozen amidst fragile volcanic glass and minerals. All types of magma ( basalt, andesite, dacite, and rhyolite) will form pumice. Pumice is similar to the liquid foam generated when a bottle of pressurized soda is opened–the opening depressurizes the soda and enables dissolved carbon dioxide gas to escape or erupt through the opening. During an explosive eruption, volcanic gases dissolved in the liquid portion of magma also expand rapidly to create a foam or froth; in the case of pumice, the liquid part of the froth quickly solidifies to glass around the glass bubbles. Pumice is so light that it actually floats on water. Huge pumice blocks have been seen floating on the ocean after large eruptions. Some lava blocks are large enough to carry small animals.
Basalt is a hard, gray to black extrusive volcanic rock, mafic (rich in iron and magnesium), fine-grained, sometimes displays frozen gas bubbles (vesicular texture), and sometimes contains phenocrysts of feldspar (Ca-rich varieties), hornblende, pyroxene, biotite mica, sometimes contains phenocrysts of feldspar (Ca-rich varieties), hornblende, pyroxene, biotite mica, sometimes quartz or olivine.
Common minerals in basalt include olivine, pyroxene, and plagioclase.
Obsidian is a very shiny natural volcanic glass. When obsidian breaks it fractures with a distinct conchoidal fracture. Obsidian is produced when lava cools very quickly. The lava cools so quickly that no crystals can form. When people make glass they melt silica rocks like sand and quartz then cool it rapidly by placing it in water. Obsidian is produced in nature in a similar way.
Obsidian is dense volcanic glass, usually rhyolite in composition and typically black in color. Compared with window glass, obsidian is rich in iron and magnesium; tiny (<.005 mm) crystals of iron oxide within the glass cause its dark color. Obsidian is often formed in rhyolite lava flows where the lava cools so fast that crystals do not have time to grow. Glass, unlike crystals, has no regular structure and therefore fractures in smooth conchoidal (curved) shapes. The intersections of these fractures can form edges sharper than the finest steel blades. Obsidian is usually black or a very dark green, but it can also be found in an almost clear form. The colors in obsidian result from the oxidation state of the chemical elements within the tiny minerals that are finely dispersed in the glass. Black color results chiefly from magnetite, Fe304. If the obsidian is highly oxidized, then the glass may contain hematite, which provides a reddish hue. Variations in the oxidation state of the iron (Fe) varieties imparts a slight greenish hue. Some obsidian is banded, a consequence of oxidation on a flow surface being folded into the lava as it continues to move.
Sedimentary rocks are formed from pre-existing rocks or pieces of once-living organisms. They form from deposits that accumulate on the Earth’s surface. Sedimentary rocks often have distinctive layering or bedding. Many of the picturesque views of the desert southwest show mesas and arches made of layered sedimentary rock.
Types of Sedimentary Rocks found in Arizona
A conglomerate is a rock consisting of individual stones that have become cemented together. They are Sedimentary rocks mostly consisting of rounded fragments.
Sandstone is composed mainly of sand-size mineral or rock grains. Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth’s crust. Like sand, Sandstone may be any color, but most common are tan, brown, yellow, red, grey, and white. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Some sandstones are resistant to weathering.
Siltstone has a composition intermediate grain size between the courser sandstone and the finer mudstones or shales. Siltstone is primarily composed of silt-sized particles defined as grains. Siltstones differ significantly from sandstones due to their smaller pores and higher propensity for containing a significant clay fraction.
Shale, also called mudstone, is a fine-grained rock whose original constituents were clay minerals, or mud. Shale is characterized by thin laminae breaking with an irregular curving fracture, often splintering and usually parallel to the often indistinguishable bedding plane. Shale is the most common Sedimentary rock.
Limestone often contains variable amounts of silica in the form of chert or flint, as well as varying amounts of clay, silt, and sand as disseminations, nodules, or layers within the rock. The primary source of calcite in limestone is most commonly marine organisms. The organisms secrete shells that settle out of the water column and are deposited on ocean floors. Limestone makes up about 10% of the total volume of all sedimentary rocks. Because of impurities, such as clay, silt, organic remains, iron oxide and other materials, many limestones exhibit different colors, especially on weathered surfaces. Limestone may be crystalline, clastic, granular, or massive depending on the method of formation. Crystals of calcite, quartz, dolomite or barite, may line small cavities on the rock. During regional metamorphism that occurs during mountain building process, limestone re-crystallizes into marble.
Limestone is partially soluble, especially in acid. Limestone is very common in architecture in North America and Europe.
Limestone has been added to paper, plastics, tiles, and other materials as both white pigment and cheap filler. It has also been added to toothpaste, breads, and cereals as a source of calcium.
Chalk is a soft, white porous sedimentary rock, a form of limestone composed of the mineral calcite. It forms under relatively deep marine conditions from the gradual accumulation of minute calcite plates. It is common to find flint and chert nodules in chalk. Chalk is relatively resistant to erosion. Chalk has been quarried since prehistory providing building material and marl for fields.
In agriculture chalk is used for raising pH in soils with high acidity. The most common forms are calcium carbonate and calcium oxide.
Halite is the mineral form of sodium chloride, commonly known as rock salt. Halite forms from isometric crystals. It is typically colorless to yellow, but may also be light blue, dark blue, and pink. Halite occurs in vast beds of sedimentary evaporate minerals that result from the drying up of enclosed lakes and seas. Salt beds may be up to 405 meters thick and underlie broad areas.
Gypsum is a very soft mineral composed of calcium sulfate dehydrate. Gypsum occurs in nature as flattened and often twinned crystals and transparent cleavable masses, called selenite. It may also occur silky, fibrous, granular, or compact. In hand- sized samples, it can be anywhere from transparent to opaque. A very fine-grained white or lightly tinted variety of gypsum is called Alabaster.
Gypsum is a common mineral with thick and extensive evaporate beds. It is also often associated with halite and sulfur.
Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot, mineral-rich fluids or, more commonly, some combination of these factors. Conditions like these are found deep within the Earth or where tectonic plates meet.
Process of Metamorphism
The process of metamorphism does not melt the rocks, but instead transforms them into denser, more compact rocks. New minerals are created either by rearrangement of mineral components or by reactions with fluids that enter the rocks. Pressure or temperature can even change previously metamorphosed rocks into new types. Metamorphic rocks are often squished, smeared out, and folded. Despite these uncomfortable conditions, metamorphic rocks do not get hot enough to melt, or they would become igneous rocks!
Types of Metamorphic Rocks found in Arizona
Slate is a fine-grained rock. It consists mainly of grains of mica and quartz, with smaller amounts of chlorite, hematite, and other minerals. Most slate is black in color but it can be red or purple, depending on it’s mineral content. Slate results when pressure created chiefly by mountain-forming movements in Earth’s crust squeezes the mica and other minerals into parallel layers.
Schists form a group of medium-grade metamorphic rocks, notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. By definition schist contains more than 50% platy and elongated minerals, often finely inter-leaved with quartz and feldspar. Schist is characteristically foliated, meaning the individual mineral grains split off easily into flakes or slabs. Most schists have been derived from clays and mud which have passed through a series of metamorphic processes involving the production of shale, slats and phyllites as intermediate steps.
Certain schists have been derived from fine-grained igneous rocks like basalt. Most schists are mica schists, but graphite and chlorite shists are also common.
Schists are frequently used as dimension stones.
A coarse-grained, foliated metamorphic rock that commonly has alternating bands of light and dark-colored minerals. Gneiss is a common and widely distributed type of rock formed by high- grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks. Gneeissic rocks are usually medium to course and largely crystallized but do not carry large quantities of mica, chloride, or other platy minerals.
Gneiss resembles schist, except that the minerals are arranged into bands. Sometimes it is difficult to tell the difference between gneiss and schist because some gneiss appear to have more mica than what it really does.
Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey. Quartzites often occur in various shades of pink and red due to varying amounts of iron oxide. Other colors are commonly due to impurities of minor amounts of other minerals.
In true quartzite, the individual quartz grains have re-crystallized along with the former cementing material to form an interlocking mosaic of quartz crystals. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hill tops. The nearly pure silica content of the rock provides little to form soil from and therefore the quartzite ridges are often bare or covered only with a very thin soil and little vegetation.
Marble:Marble is a non-foliated metamorphic rock resulting from the metamorphism of limestone or dolostone. It is composed mostly of calcite ( a crystalline form of calcium carbonate). Marble is capable of taking a high polish.
Pure white marble is the result of metamorphism of very pure limestones. The characteristic swirls and veins of many colored marble varieties are usually die to various mineral impurities such as clay, silt, sand, iron oxides or chert which were originally present as grains or layers in the limestone. Green coloration is often due to serpentine resulting from originally high magnesium limestone or dolostone with silica impurities. These various impurities have been mobilized and re-crystallized by the intense pressure and heat of the metamorphism.