William Smith

In 1769 in a little town in Oxfordshirecounty in south central England, England, a child with the very ordinary name of William Smith was

born into the poor family of a village blacksmith. He received rudimentary village schooling, but mostly he

roamed / nomadic / nomad / his uncle's farm collecting the fossils that were so abundant / abandon / in the rocks of the Cotswold hills . When he

grew older, William Smith taught himself surveying from books he bought with his small savings / savings account / checking account / , and at the age

of eighteen he was apprenticed to / trainee, pupil a surveyor of the local parish / preach/ missionary / father / bishop. He then proceeded to teach himself geology , and

when he was twenty-four, he went to work for the company that was excavating/ exhume the Somerset Coal Canal in the

south of England. / village / valley /

l      archeology: fossil / anthropology : artifacts / antique/ ruins / geologist: the earth crust

 

This was before the steam locomotive / tube / piston / cylinder, and canal building was at its height / heyday/ prime . The companies building the

canals to transport coal needed surveyors to help them find the coal deposits worth mining as well as to

determine the best courses for the canals. This job gave Smith an opportunity to study the fresh rock outcrops

created by the newly dug canal. He later worked on similar jobs across the length and breadth of England,

all the while studying the newly revealed strata and collecting all the fossils he could find. Smith used mail coaches to

travel as much as 10,000 miles per year. In 1815 he published the first modern geological map, A Map of the

Strata of England and Wales with a Part of Scotland, a map so meticulously researched that it can still be used

today.

 

In 1831 when Smith was finally recognized by the Geological Society of London as the father of English

geology, it was not only for his maps but also for something even more important . Ever since people had begun

to catalog the strata in particular outcrops, there had been the hope that these could somehow be used to

calculate geological time. But as more and more accumulations of strata were cataloged in more and more places,

it became clear that the sequences of rocks sometimes differed from region to region and that no rock type was

ever going to become a reliable time marker throughout the world. Even without the problem of regional

differences, rocks present a difficulty as unique time markers. Quartz is quartz—a silicon ion surrounded by four

oxygen ions—there’s no difference at all between two-million-year-old Pleistocene quartz and Cambrian quartz

created over 500 million years ago.

 

Pleistocene

n. geological era in which much of the earth was covered in ice (approximately 2 million to 10000 years ago)

 

 

ion

n. (Physics, Chemistry) electrically charged atom formed by the loss or gain of an electron; electrically charged particle formed in a gas

 

As he collected fossils from strata throughout England, Smith began to see that the fossils told a different

story from the rocks. Particularly in the younger strata, the rocks were often so similar that he had trouble

distinguishing the strata, but he never had trouble telling the fossils apart. While rock between two consistent

strata might in one place be shale and in another sandstone, the fossils in that shale or sandstone were always the

same. Some fossils endured through so many millions of years that they appear in many strata, but others occur

only in a few strata, and a few species had their births and extinctions within one particular stratum. Fossils are

thus identifying markers for particular periods in Earth's history.

 

Not only could Smith identify rock strata by the fossils they contained, he could also see a pattern emerging:

certain fossils always appear in more ancient sediments, while others begin to be seen as the strata become more

recent. By following the fossils, Smith was able to put all the strata of England's earth into relative temporal

sequence. About the same time, Georges Cuvier made the same discovery while studying the rocks around Paris.

Soon it was realized that this principle of faunal 動物種(animal) succession was valid not only in England or France but

virtually everywhere. It was actually a principle of floral succession as well, because plants showed the same

transformation through time as did fauna. Limestone may be found in the Cambrian or—300 million years

later—in the Jurassic strata, but a trilobite—the ubiquitous marine arthropod that had its birth in the

 

Cambrian—will never be found in Jurassic strata, nor a dinosaur in the Cambrian.

 

principle

n. doctrine, tenet, precept; fundamental law, primary law on which other laws are based

 

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