Chronostratigraphy is the branch of stratigraphy that studies the age of rock strata in relation to time. The ultimate aim of chronostratigraphy is to arrange the sequence of deposition and the time of deposition of all rocks within a geological region, the entire geologic record of the Earth; the standard stratigraphic nomenclature is a chronostratigraphic system based on palaeontological intervals of time defined by recognised fossil assemblages. The aim of chronostratigraphy is to give a meaningful age date to these fossil assemblage intervals and interfaces. Chronostratigraphy relies upon isotope geology and geochronology to derive hard dating of known and well defined rock units which contain the specific fossil assemblages defined by the stratigraphic system; as it is very difficult to isotopically date most fossils and sedimentary rocks directly, inferences must be made in order to arrive at an age date which reflects the beginning of the interval. The methodology used is derived from the law of superposition and the principles of cross-cutting relationships.

Because igneous rocks occur at specific intervals in time and are instantaneous on a geologic time scale, because they contain mineral assemblages which may be dated more and by isotopic methods, the construction of a chronostratigraphic column relies upon intrusive and extrusive igneous rocks. Metamorphism associated with faulting, may be used to bracket depositional intervals in a chronostratigraphic column. Metamorphic rocks can be dated, this may give some limits to the age at which a bed could have been laid down. For example, if a bed containing graptolites overlies crystalline basement at some point, dating the crystalline basement will give a maximum age of that fossil assemblage; this process requires a considerable degree of effort and checking of field relationships and age dates. For instance, there may be many millions of years between a bed being laid down and an intrusive rock cutting it. Chronostratigraphic units, with examples: eonothemPhanerozoic erathemPaleozoic system – Ordovician series – Upper Ordovician stage – Ashgill It is important not to confuse geochronologic and chronostratigraphic units.

Chronostratigraphic units are geological material, so it is correct to say that fossils of the species Tyrannosaurus rex have been found in the Upper Cretaceous Series. Geochronological units are periods of time and take the same name as standard stratigraphic units but replacing the terms upper/lower with late/early, thus it is correct to say that Tyrannosaurus rex lived during the Late Cretaceous Epoch. Chronostratigraphy is an important branch of stratigraphy because the age correlations derived are crucial to drawing accurate cross sections of the spatial organization of rocks and to preparing accurate paleogeographic reconstructions. Biostratigraphy Chronozone Geochronology Geologic record Geologic time scale Isotope geology Law of superposition List of geochronologic names Stratigraphy Tectonostratigraphy

Isaac B. Desha

Isaac Bledsoe Desha was a 19th-century American tanner, convicted of murdering one man in Kentucky, confessed to murdering another in Texas. He was notable as the son of Joseph Desha. Shortly after his father's election as governor in 1824, Desha was accused of robbing and killing a man named Francis Baker, passing through Kentucky. Circumstantial evidence implicated Desha. Given the heated political environment of the Old Court-New Court controversy, allies of his father claimed that the governor's political enemies had framed his son; the governor's legislative allies passed legislation providing for a favorable change of venue for the trial, the governor used his appointment power to ensure that sympathetic judges would hear the case. Isaac Desha was twice convicted, but both times, the judge in the case set aside the verdict on procedural grounds. While awaiting a third trial, Desha attempted suicide by slitting his throat, but doctors saved his life, reconnecting his severed windpipe with a silver tube.

Shortly after the suicide attempt, Governor Desha issued a pardon for his son. Isaac Desha assumed an alias, he went to New Orleans. From there, he traveled with a man named Thomas Early to Texas; when Early went missing during their travels, Desha fell under suspicion. A former Kentuckian living in Texas recognized Desha. Arrested soon after Early's body was found, Desha confessed to the murder after being recognized by a second man from Kentucky. A day before his trial was to start, Desha died of a fever. A legend soon arose that he had faked his death and fled to Hawaii, where he married a native woman and fathered several children. Historians have debunked that myth. Isaac Bledsoe Desha was born January 1, 1802, he was named for his maternal grandfather. Educated in the local schools, for a time Isaac attended a school run by Mr. Bailey and boarded with Bailey's father. In October 1817, he was apprenticed to a tanner, he lived and studied with Logan until May 1821. In November 1823, the young man married Cornelia Pickett.

Desha's sister Ellen had married Pickett's brother James. Desha's father Joseph was elected as governor of Kentucky in August 1824; the primary issue in the campaign was relief for the state's large debtor class, still reeling from the Panic of 1819. The state's voters split between those supporting laws favorable to debtors – called the Relief Party – and those supporting laws that protected creditors – called the Anti-Relief Party. Shortly before Desha's election, the Kentucky Court of Appeals had struck down some legislation as unconstitutional, passed by the Relief Party a majority in the Assembly. After Desha was elected, Relief legislators, who held majorities in both houses of the General Assembly, attempted to remove the offending judges from office. Failing to achieve the needed two-thirds majority, the legislature passed a reorganization act abolishing the Court of Appeals and replacing it with a new court. Desha appointed justices favoring relief; the original court continued to claim authority as the court of last resort in the state.

It was a politically tumultuous time. On the night of November 1, 1824, Desha attended a celebration at a neighbor's house, he stayed the night at Doggate's Tavern in Fairview, just over the county line in Fleming County. The next morning, he ate breakfast at the tavern, joined by eight other men, including Francis Baker. Editor of the Mississippian newspaper in Natchez, Baker was returning to his hometown of Trenton, New Jersey to marry a young woman there. Over breakfast, Baker mentioned wanting to visit a friend, Captain John Bickley, who lived in the area. Desha remarked that he knew where Bickley lived and, intending to ride in that direction, asked if Baker wanted to join him. Baker accepted, the two men left about 8 a.m. toward Maysville. Desha rode his bay mare and Baker his gray mare, a fine horse that had attracted much attention during his travel through Kentucky. About 10 a.m. one of Desha's neighbors encountered the riderless gray mare, still rigged with saddle and bridle. Catching the horse, he rode it up the road, shortly finding Desha's riderless bay, with a saddle but no bridle.

He noticed blood on the neck and withers of Desha's horse. Further along, the neighbor encountered Desha on foot. Desha said, he did not volunteer how the two horses had escaped his control, but mounted the gray mare and returned home. That day, friends at Desha's tannery noticed that he was unusually quiet and asked what was wrong, he said that he had been kicked by a horse and cut his finger in separate incidents the previous day. His unusual behavior continued to the point that Desha's pregnant wife Cornelia moved out of the house and refused to return, she gave birth to their daughter and only child, who she named after her mother. She never returned to Desha. Over the next few days, neighbors began to discover items along the route Desha and Baker had taken from Doggate's Tavern to Maysville; these included a bloody glove, a pair of saddlebags with the bottoms cut out, Desha's missing horse bridle. On November 8, three men discovered a man's body – its upper half covered by a log – about 50 yards off the road on the Fleming County side.

The men did not move the body, but reported it to local authorities, who returned to recove

Smithland, Iowa

Smithland is a city in Woodbury County, United States. It is part of IA -- NE -- SD Metropolitan Statistical Area; the population was 224 at the 2010 census. Smithland is one of the oldest settlements in Woodbury County. In 1857, clashes between settlers and Indians began at what is now Smithland which would afterward culminate in the Spirit Lake Massacre. Smithland is located at 42°13′45″N 95°55′55″W; the town is situated near the Little Sioux River, where the river valley courses through the Loess Hills on its way to the floodplain of the Missouri River. According to the United States Census Bureau, the city has a total area of 0.37 square miles, all of it land. At the 2010 census, there were 224 people, 100 households and 65 families living in the city; the population density was 605.4 inhabitants per square mile. There were 109 housing units at an average density of 294.6 per square mile. The racial makeup of the city was 97.3% White, 2.2% from other races, 0.4% from two or more races. Hispanic or Latino of any race were 3.1% of the population.

There were 100 households of which 23.0% had children under the age of 18 living with them, 44.0% were married couples living together, 13.0% had a female householder with no husband present, 8.0% had a male householder with no wife present, 35.0% were non-families. 32.0% of all households were made up of individuals and 21% had someone living alone, 65 years of age or older. The average household size was 2.24 and the average family size was 2.66. The median age was 49 years. 19.6% of residents were under the age of 18. The gender makeup of the city was 49.6 % female. At the 2000 census, there were 101 households and 72 families living in the city; the population density was 613.0 per square mile. There were 114 housing units at an average density of 316.2 per square mile. The racial makeup of the city was 99.10% White, 0.45% Native American, 0.45% from two or more races. Hispanic or Latino of any race were 0.45% of the population. There were 101 households of which 19.8% had children under the age of 18 living with them, 56.4% were married couples living together, 8.9% had a female householder with no husband present, 28.7% were non-families.

27.7% of all households were made up of individuals and 15.8% had someone living alone, 65 years of age or older. The average household size was 2.19 and the average family size was 2.60. 19.0% of the population were under the age of 18, 7.2% from 18 to 24, 17.2% from 25 to 44, 29.4% from 45 to 64, 27.1% who were 65 years of age or older. The median age was 49 years. For every 100 females, there were 100.9 males. For every 100 females age 18 and over, there were 90.4 males. The median household income was $31,406 and the median family income was $33,750. Males had a median income of $31,250 and females $17,188; the per capita income was $14,722. About 4.0% of families and 6.4% of the population were below the poverty line, including 7.0% of those under the age of eighteen and none of those sixty five or over