Wednesday, July 29, 2009
The Permian Era, 290 to 248 Million Years Ago
The recent research and findings of DNA and other organic bits found in Permian salt deposits has excited much of the science community. Microbiology and biochemistry professor Jack Griffith found organic material in water that was trapped in the salt left behind as land locked interior oceans evaporated over time. Evidence of these interior bodies of ocean saltwater still exists in the United States as The Great Salt Lake of Utah. The Bonneville Salt Flats, where people go to break land speed records, is nothing more than an interior ocean saltwater lake bed that evaporated.
The Permian period lasted from 290 to 248 million years ago and was the last period of the Paleozoic Era. The distinction between the Paleozoic and the Mesozoic is made at the end of the Permian in recognition of the largest mass extinction recorded in the history of life on Earth. It affected many groups of organisms in many different environments, but it affected marine life the most. Some groups survived the Permian mass extinction in greatly diminished numbers, but they never again reached the ecological dominance they once had, clearing the way for another group of sea life. On land, a relatively smaller extinction of diapsids and synapsids cleared the way for other forms to dominate, and led to what has been called the “Age of Dinosaurs.” Also, the great forests of fern-like plants shifted to gymnosperms, plants with their offspring enclosed within seeds. Modern conifers, the most familiar gymnosperms of today, first appear in the fossil record of the Permian. In all, the Permian was the last of the time for some organisms and a pivotal point for others, and life on earth was never the same again.
The global geography of the Permian included massive areas of land and water. By the beginning of the Permian, the motion of the Earth's crustal plates had brought much of the total land together, fused in a super continent known as Pangea. Many of the continents of today in somewhat intact form met in Pangea which stretched from the northern to the southern pole. Even today you can reassemble the continents that once made up Pangea together like a giant jig saw puzzle proving that they had once been one large continent. Only Asia was broken up at the time. Most of the surface area of the Earth was occupied by a corresponding single ocean, known as Panthalassa, with a smaller sea to the east of Pangea known as Tethys. Like today, the Pacific is the larger ocean and the Atlantic is the smaller ocean.
Models indicate that the interior regions of this vast continent were probably dry, with great seasonal fluctuations, because of the lack of the moderating effect of nearby bodies of water, and that only portions received rainfall throughout the year. There are indications that the climate of the Earth shifted at this time, and that glaciation decreased, as the interiors of continents became drier.
One of these areas is The Glass Mountains which is located in southwestern Texas. The mountain range has been described as about 24 miles long and between 6 and 15 miles wide. The mountains are made up of limestone, shale, sandstone, dolomite, marl, and other rocks, sediment, clay, and sand.
This mountain range is part of a relatively large geographical area marked by the presence of geological features dating from the Permian period, dated 286 to 245 million years ago. This area, called the Permian Basin, underlies parts of western Texas and southeastern New Mexico in the southwestern United States. Sediments from that era cover a thickness of some 12,000 feet.
The Permian features in the southwestern United States are mostly marine in nature; when the Permian period began, and what is now the Glass Mountains were underwater. As time went on, the ocean evaporated, and when the Permian ended, the former ocean was dry.
The Glass Mountains themselves have been chosen as the standard section for the Permian period because of the presence of a continuous layer of Permian sediment 1500 to 2000 m thick.
The strata of the Glass Mountains contain a number of fossils, many of which are from the Permian. One part of the significance of the fossil finds in the Glass Mountains and other parts of the Delaware Basin is the use of their occurrence to classify strata, layers of rock marked by different times of deposition; in fact, the presence of fossils in various strata have been the primary means of classification, along with features of the rock itself. Fossils found in the Glass Mountains, found in marine sediment, are those of marine organisms. The selection of fossils includes algae, sponges, bryozoans, brachiopods, crinoids, conodonts, coral, ostracodes, gastropods, nautiloids, and other early forms of marine life. The Permian fossils of the Glass Mountains are shallow, warm-water marine life, like the kinds expected in a modern-day coral reef; the results are to be expected for what was once the Capitan Reef millions of years ago.
Some of these are suitable for stratigraphic correlation, the classification of strata from different areas into a chronological framework to determine which rock was laid down at similar times, because of various factors, like (1) sufficient numbers of fossils, both in an individual site and in other sites to be correlated, (2) sufficient rate of change in the population through time to permit analysis of evolutionary change through the strata, and (3) enough study of the populations to allow for a knowledgeable analysis.
Of special interest are fusulinids, a kind of foraminifer (a kind of shelled protist), and ammonoids, a kind of mollusk related to the modern-day chambered nautilus. The fossilized shells of these organisms have been used in early stratigraphic correlation. Many of the fossils of Permian life were discovered within the various sediments that compose the layered formations of the Glass Mountains. Fossils in the Glass Mountains have been used for determining correlations among sites in North America and in other places. As mentioned, the Permian series of the Glass Mountains is the standard series for correlation with other strata in North America.
As mentioned, the fossils in these areas have been important criteria for correlations. Fossil correlations from one area to another can be used to evaluate sediments from similar dates. The Ural Mountains, Russia, also contain similar fossil sites. Other similar sites in the Permian are found in areas across the western United States, including a band from Kansas to Texas. There have also been similar discoveries in other parts of the Americas, including Central and South America and northern North America. The geological knowledge also has some applied use, as economic geology, which is concerned with natural resources like natural gas, oil, and minerals, is interested in geological dating.
In short, what is known from the Permian series in the Glass Mountains has been used for correlations with stratigraphy and fossils elsewhere, and the fossils found in the Glass Mountains have been the primary method of determining these correlations.
Now in summation, when those who want to make the claim that the earth is 10,000 years old based on a single source documenting oral traditions from nomadic tribes of 2,500 years ago noting that nothing is based on any scientific fact; their credibility pales in comparison to the scientific evidence noted in this posting.