Classic TEKTITES Book By John O ' Keefe (1963) Ex - Library In, No DJ
Item History & Price
| Reference Number: Avaluer:4874733 |
Offered here for your kind consideration is a copy of the 1963 hard-cover classic book TEKTITES edited by John A. O'Keefe.
and published by The University of Chicago Press. Allowing for inflation that would be about $100 in 2019.
It's an ex-library book with all that entails, discarded by Harvard College Observatory. Still, a good, readable copy.
There are at present 190 confirmed meteorite and comet impact crater sites on Ea...rth. The enormous temperatureand pressure produced when they strike planet Earth at hyper-ballistic speeds may profoundly affect local or area Earth
rocks and soil, melting, shattering, or altering them. These varieties of rock associated with the impact events are collectively
known as impactites.
Once considered among the most mysterious rocks on Earth, glassy tektites are a naturally-occuring impactite, Earth rocks
or sand affected, sometimes profoundly so, by the impact pressure of an asteroid or comet. Most tektites show signs of having
been twice melted: first, as they are thrown out of the lower atmosphere, then becoming aerodynamically-sculpted as they return
to Earth often landing many kilometers or miles from the impact in strewn-fields.
Those found mainly in the Czech Republic are called Moldavites and originated from the Ries, Germany Impact. Bediasites found
in Texas and Georgiaites in Georgia are tektites originating from the Chesapeake Bay impact crater. The Australasian strewn field
is the largest and geologically youngest of the tektite strewn fields and the only one thus far with no known associated impact crater.
The term "Tektite" was first coined by F.E. Seuss, an Austrian geologist, in 1900, from the Greek word tektos meaning molten. They are found scattered about the surface of the Earth in many localities called "strewn fields." Georgia tektites, or "Georgiaites, " are part of the North American strewn field.A tektite is a high-silica glassy object that can range in size from the microscopic to weights of many kilograms. They generally have aerodynamically formed shapes like buttons, teardrops and dumbbells. In some ways, tektites resemble obsidian glasses that are formed from volcanic activity here on earth. However, tektites are special in that they contain about 1000 times less water than obsidian, exhibit a low alkali content, and contain different types of iron and materials than normal terrestrial glass.There have been several theories as to the origin of tektites that range from: a glassy variety of meteorite, lunar volcanoes, meteoroid impacts on the moon, and large meteoroid impacts on the Earth. Other ideas followed, and some investigators changed their minds several times, but the generally accepted theory is that tektites are created as a result of high-energy meteoroid impacts that melt the surrounding earth to form these special glasses. Because of the multitude of origin theories surrounding tektites, Henry Faul, a respected geo-chemist, was quoted as saying "...tektites are probably the most frustrating stones ever found on Earth."
The pressure and heat of impact from a large asteroid or comet strike is believed to be the most powerfulnaturally-occurring event in nature. It causes more destruction than that from an earthquake, tsunami orsuper-volcano, equivalent to hundreds of Hydrogen bombs detonating simultaneously. Local and area rocksand soil are instantly vaporized and the impact creates a crater far larger than the size of the impacting body.Small craters look like simple bowls. Larger ones may contain a peak or central uplift and multiple rings.
There is, quite understandably, a growing interest in large meteorites, asteroids, and comets. That suchlarge objects have struck Earth in the past and will continue to do so in future is something mainstreamscientists have only since about 1970 begun to realize. Luckily, these disasters do not occur very oftenor on a fixed schedule.
At present, there are 190 recognized remains of impact structures. Every year, one or two potential newones are discovered. Perhaps as many as one hundred sites are awaiting study. The confirmation of newimpact craters is by no means a speedy process as there are probably fewer professional impact cratergeologists in the world than workers in an average McDonald's Restaurant. Further, since 95% of Earthis uninhabited, most possible sites are located in remote regions.
I would love to keep this book, however, now that I am actually retired after sixty years of collecting, I must be getting rid of some of my most cherished possessions.
It is no wonder the geologically inactive Moon still has millions of well-preserved impact craters. Earth though is an active planet. Fresh impact craters are quickly eroded away by natural forces, buried by sediment or mud, overgrown with vegetation, distorted by plate tectonics, uplifted during mountain forming, covered with lava, sheared off by glaciers, etc.
The combined pressure and heat unleashed by such impacts obviously affect local or area Earth rocks, sand, and soil, sometimes in quite profound ways, vaporizing billions of tons of rock and soil and shattering rocks.
Long after an impact crater has vanished from the landscape material altered by the impact, known as impactites, may yet remain.
and published by The University of Chicago Press. Allowing for inflation that would be about $100 in 2019.
It's an ex-library book with all that entails, discarded by Harvard College Observatory. Still, a good, readable copy.
There are at present 190 confirmed meteorite and comet impact crater sites on Ea...rth. The enormous temperatureand pressure produced when they strike planet Earth at hyper-ballistic speeds may profoundly affect local or area Earth
rocks and soil, melting, shattering, or altering them. These varieties of rock associated with the impact events are collectively
known as impactites.
Once considered among the most mysterious rocks on Earth, glassy tektites are a naturally-occuring impactite, Earth rocks
or sand affected, sometimes profoundly so, by the impact pressure of an asteroid or comet. Most tektites show signs of having
been twice melted: first, as they are thrown out of the lower atmosphere, then becoming aerodynamically-sculpted as they return
to Earth often landing many kilometers or miles from the impact in strewn-fields.
Those found mainly in the Czech Republic are called Moldavites and originated from the Ries, Germany Impact. Bediasites found
in Texas and Georgiaites in Georgia are tektites originating from the Chesapeake Bay impact crater. The Australasian strewn field
is the largest and geologically youngest of the tektite strewn fields and the only one thus far with no known associated impact crater.
The term "Tektite" was first coined by F.E. Seuss, an Austrian geologist, in 1900, from the Greek word tektos meaning molten. They are found scattered about the surface of the Earth in many localities called "strewn fields." Georgia tektites, or "Georgiaites, " are part of the North American strewn field.A tektite is a high-silica glassy object that can range in size from the microscopic to weights of many kilograms. They generally have aerodynamically formed shapes like buttons, teardrops and dumbbells. In some ways, tektites resemble obsidian glasses that are formed from volcanic activity here on earth. However, tektites are special in that they contain about 1000 times less water than obsidian, exhibit a low alkali content, and contain different types of iron and materials than normal terrestrial glass.There have been several theories as to the origin of tektites that range from: a glassy variety of meteorite, lunar volcanoes, meteoroid impacts on the moon, and large meteoroid impacts on the Earth. Other ideas followed, and some investigators changed their minds several times, but the generally accepted theory is that tektites are created as a result of high-energy meteoroid impacts that melt the surrounding earth to form these special glasses. Because of the multitude of origin theories surrounding tektites, Henry Faul, a respected geo-chemist, was quoted as saying "...tektites are probably the most frustrating stones ever found on Earth."
The pressure and heat of impact from a large asteroid or comet strike is believed to be the most powerfulnaturally-occurring event in nature. It causes more destruction than that from an earthquake, tsunami orsuper-volcano, equivalent to hundreds of Hydrogen bombs detonating simultaneously. Local and area rocksand soil are instantly vaporized and the impact creates a crater far larger than the size of the impacting body.Small craters look like simple bowls. Larger ones may contain a peak or central uplift and multiple rings.
There is, quite understandably, a growing interest in large meteorites, asteroids, and comets. That suchlarge objects have struck Earth in the past and will continue to do so in future is something mainstreamscientists have only since about 1970 begun to realize. Luckily, these disasters do not occur very oftenor on a fixed schedule.
At present, there are 190 recognized remains of impact structures. Every year, one or two potential newones are discovered. Perhaps as many as one hundred sites are awaiting study. The confirmation of newimpact craters is by no means a speedy process as there are probably fewer professional impact cratergeologists in the world than workers in an average McDonald's Restaurant. Further, since 95% of Earthis uninhabited, most possible sites are located in remote regions.
I would love to keep this book, however, now that I am actually retired after sixty years of collecting, I must be getting rid of some of my most cherished possessions.
It is no wonder the geologically inactive Moon still has millions of well-preserved impact craters. Earth though is an active planet. Fresh impact craters are quickly eroded away by natural forces, buried by sediment or mud, overgrown with vegetation, distorted by plate tectonics, uplifted during mountain forming, covered with lava, sheared off by glaciers, etc.
The combined pressure and heat unleashed by such impacts obviously affect local or area Earth rocks, sand, and soil, sometimes in quite profound ways, vaporizing billions of tons of rock and soil and shattering rocks.
Long after an impact crater has vanished from the landscape material altered by the impact, known as impactites, may yet remain.
