A glimpse of the Future

There is good evidence that the next advance of the earth’s glaciers will occur within the next thousand years or so. A catastrophe for humanity, but I am optimistic enough to suppose that as a species we will survive. Our few remaining short-lived descendants, as they shiver before fires at the mouths of their caves will tell each other stories of a legendary past when their long-lived ancestors enjoyed a life of abundance in a former golden age – the Happy Holocene.

Meanwhile, back in the Holocene…

Today our technology is so advanced that more than 60% of its 8 billion plus citizens are free to pursue fields of skill and knowledge that have nothing directly to do with food production. In developed, industrialised nations, that percentage must be nearer 90%.

One of these fields of knowledge is geology.

The International Union of Geological Sciences (IUGS), founded in 1961, is the peak governing body of geology. Under its aegis are a number of Commissions covering such things as Structure and Tectonics, Geochemistry, Ethics, History of Geology, Geological Education and so on. The oldest and probably the most important of these Commissions is the International Commission on Stratigraphy (ICS) which is tasked with responsibility for the subdivision of geological time going back 4.6 billion years (4.6 Ga).

To Fully Understand this Post, you will Need to Know How Geologists Divide Time

Time divisions and subdivisions are based on the stratigraphic record – the sequential accumulation of sediments and the fossil assemblages (if any) within them. Boundaries between subdivisions are based on significant, widespread and geologically rapid, transitions in the overall depositional environment. Localities where these key transitions are well exposed are referenced as type-localities and dated by isotopic methods. Each distinctive rock/fossil assemblage (divisions and subdivisions) are given a name, thus reifying them as a “thing”. Many of the names go back more than 200 years and reflect the happenstance of early geological research (see my previous post, The Invention of the Paleozoic). On a stratigraphic chart, time divisions are organised by nested hierarchies of ever smaller intervals of time. Eons (sometimes called Eonothems) are the longest: there are four of these in the 4.6 Ga geological record. Together, these four Eons are subdivided into fifteen Eras (Erathems), and these fifteen Eras together contain twenty-six Periods (Systems). The Periods contain 38 Epochs (Series), and the Epochs themselves contain over a 100 Stages (Ages).

A Stage has the shortest time interval and the smallest geographical extent of the time division.

The boundaries of Eons and Eras mark changes of global extent in tectonic processes, atmospheric composition and biospheric evolution and reflect the time evolution of these forces. However, as will become apparent, the boundaries of Periods, Epochs and Stages are much more dependent on locally available evidence, subjective judgment of experts, and the historical development of classification schemes.

If we consider the stratigraphic chart as a Library of Time, then the Eons are books, the Eras chapters, the Periods paragraphs, the Epochs sentences, and the Stages words. The last words of the last paragraph of the last chapter of the last book to be added to the library are: “to be continued…”

To carry out their task, the ICS created a number of Sub Commissions, each responsible for one of the 26 Periods in the stratigraphic record. The most recent Period, the one we live in today, is known as the Quaternary and began 2.58 million years (2.58 Ma) ago with the start of the Pleistocene Ice Age.

Geological subdivisions of the recent past, according to the ICS. Redrawn from their official chart. 

The Cenozoic

A little over sixty-six million years ago (66 Ma), a 10 km wide rogue asteroid, travelling at 40,000 kph collided with what is now the Yucatan Peninsula of Mexico. This global catastrophe caused the near instantaneous extinction of 75% of all species of life on earth, including the non-avian dinosaurs. The event formed a centimeters-thick global sedimentary marker for the end of the Mesozoic Era and the beginning of the Cenozoic Era.

Graph A: Cenozoic temperatures over the past 65 Ma. The Quaternary Period and the Pleistocene Epoch begin at 2.6 Ma on the extreme right of the graph (labelled as Pleistocene Ice Age).

For the first 20 Ma of the Cenozoic, global temperatures were 10-15°C higher than today (and atmospheric CO2 levels 2-5 times higher), supporting a burst of adaptive evolutionary radiation of all Orders, Families and Species to fill the recently-vacated ecological niches of life. The Mammalian Order of Primates to which we belong evolved during this time.

Beginning around 45 Ma, the Hothouse temperatures which had prevailed during the early Cenozoic commenced a long slow fall. By 35 Ma, permanent ice sheets had become established over the Antarctic Continent. By 2.6 Ma, permanent ice sheets had also formed over Arctic regions. Permanent ice at both poles is the definition of an Ice Age. A new Period and a new Epoch had begun.

The Quaternary Period

The lower boundary (i.e. the beginning) of the Quaternary Period and the Pleistocene Epoch is defined by the start of the Pleistocene Ice Age when temperatures plummeted, and kilometer-thick ice became generally established over land and sea at high- to mid-latitude areas around both poles. These extreme cold conditions are known as Glacial and they affected the nature of sediments, and the fossils within them, that were deposited all over the world.

The maximum extent of Ice sheets during the last glacial episode around 20,000 years ago. Image source, NASA.

The end of the Pleistocene Epoch should therefore be when glacial conditions cease for a significant period of geological time (i.e. at least a million years). That has not happened yet. Considering the duration of previous Ice Ages, each of which lasted many tens of millions of years (such as the Sturtian Ice Age in the Proterozoic Eon around 700 Ma, the “Snowball Earth” Ice Age at the end of the Ordovician Era around 440 Ma, or the long-lived Late Paleozoic Ice Age centered around 300 Ma), the Pleistocene Ice Age – currently only 2.6 Ma old – has millions of years yet to run. (see my post, Climate Change Explained in Three Graphs). Nor are the general icy conditions of the Pleistocene ameliorating with the passage of time. The opposite is true. Glacial advances in the latter part of the Pleistocene, starting around a million years ago, have been longer, colder and more extensive than those of the earlier part of the Epoch. The change to longer cycles and colder glacial temperatures is referred to as the Mid-Pleistocene Transition.

The evidence thus indicates that the Pleistocene Ice Age is becoming ever colder with time and, as Ice Ages go, has only just begun.

The Holocene

We live in the Holocene – an interval of ice retreat, relatively warm temperatures and sea level rise. It began 11,700 (0.0117 Ma) years ago.

Pleistocene geological records show the presence of at least 45 similar temporary retreats of ice. These are called Interglacials and make up around 20% of Pleistocene time. The exact number of Interglacials depends on how their start and end dates are defined. The warm conditions of the Holocene (“warm” only with respect to the preceding glacial) are not significantly different from any of the previous interglacial episodes within the Pleistocene.

Graph B: Temperatures during the last 0.45 Ma of the Pleistocene as measured in Antarctic ice cores. Five Interglacial events are recorded, the last two labelled Eemian and Holocene. Data from www.climatedata.info    

During the last interglacial (the Eemian), elephant and hippopotami gamboled on the mud flats of the River Thames. With the return of glacial conditions these species migrated south but, 120,000 years later with the arrival of the Holocene, another species of large out-of-Africa mammal gambols, once again, on the banks the Thames.  

Graph B, above, shows changes in air temperature (blue) and CO2 concentration (red) over Antarctica, as measured in the VOSTOK and EPICA deep ice cores. Broadly similar graphs can be produced for other regions of the globe, but the Antarctic data provides the best resolution.  The graph covers the last 20% of the Pleistocene. Five upward spikes in temperature are apparent: these are Interglacial episodes of ice retreat – the last two labeled on the graph as “Eemian” and “Holocene“. During the 10,000 year-long Eemian, West Antarctica and the Ross Sea were ice fee (Nature Geoscience 2026, https://doi.org/10.1038/s41561-026-1988-1). The Emperor Penguins survived. There were no tipping points.

There is another important takeaway from this graph: there is good correlation between temperature and CO2, but the peaks and troughs of CO2 lag the peaks and troughs of temperature by 500-1000 years. This tells us that, whereas temperature might be acting as a control on atmospheric CO2 levels, CO2 cannot be controlling temperature (since an effect cannot precede its cause).  

Graph C: Greenland ice core data from Vinther et al 2009: https://www.nature.com/articles/nature08355. and Macassar Strait benthic sediment data from Rosenthal et al 2013  http://science.sciencemag.org/content/342/6158/617. Compilation of the two data sets onto one graph with common scales is by Andy May.   

Graph C shows air and sea temperatures over the past 10,000 years – the last 85% of the Holocene. The temperature data come from oxygen isotope ratios measured in ice cores from Greenland (orange line) and sea-floor sediment (benthic) cores from the Western Pacific (black line). The good correlation of temperature variation with time between regions on opposite sides of the globe, based 0n two completely different deposit types, is compelling.  

Other graphs of Holocene temperatures using different proxy methods and from different locations around the globe have been published. You can view a comparison of these graphs, in Nature Science  Data, 2020 HERE. Although differing in detail, they all show a similar pattern to graph C.

From the graph we can see a steep initial rise in Holocene temperatures to a plateau around 10,000-5000 years ago. This time interval is known as the Holocene Climate Optimum.  Optimum, that is, with respect to life on earth. During the HCO, the only permanent ice to survive in the world were those of Antarctica, Greenland and the high plateaus and valleys of the great mountain ranges.

The HCO was followed by a slow and gradual decline in global temperatures and the reappearance and steady advance of mountain glaciers, reaching their maximum extent during the informally named Little Ice Age. The LIA began around 800 years ago and lasted until the middle of the 19th century. Its coldest temperatures (nadir) occurred during the 17th Century – a century of global failed harvests, plagues, invasions, revolutions, civil war, religious pogroms and, in Europe and North America, the judicial murder of thousands of harmless old women accused of witchcraft. 

See “Global crisis: Climate Change and Catastrophe in the 17th Century” by Geoffrey Parker, 2013, Yale University Press: ISBN 978-0-300-15323-1;

also “The Crisis of the 17th Century” by Oxford historian Hugh Trevor Roper, 1967, Liberty Fund, ISBN 978-1-61487-084-4).

During the “Little Ice Age” the world had a modest foretaste of what a return to full glacial conditions might mean for our civilisation. That inevitable return will not be to a new Ice Age, just the return, after a brief period of relief, to the normal conditions of the Pleistocene Ice within which we are already living.

Is the Holocene Unique among Pleistocene Interglacials?

Comparing graphs B and C, all the interglacials of the Pleistocene for which we have sufficient resolution show a similar strongly skewed pattern – a steep initial rise to a plateau, followed by a long slow fall to Glacial or Neoglacial conditions. The relentless decline in global temperature following the Holocene Climate Optimum follows this pattern and provides an ominous pointer to the next episode of Pleistocene glaciation.

Beginning around 100-150 years ago (at the extreme right of the ice-core data of graph C), there is a steep upward spike in global temperature of 1-1.5° C.  This is the Modern Warm Period (MWP) – the subject of much current existential angst from scientists who should know better (see my previous post HERE). But modern global temperatures are only “warm” when compared to the anomalously low temperatures of the preceding Neoglacial. Compared to temperatures that were normal for the majority of the Holocene, today’s temperatures are relatively cool. Compared to temperatures that were normal for the first 60 million years of the Cenozoic – when life on earth boomed – they are catastrophically cold.

From graph C we can also see that increases and decreases in global temperature of up to 3° C, over relatively short time periods, have occurred every 500-1000 years or so throughout Holocene time.

There is nothing unusual or remarkable about the Holocene other than that it corresponds with and helped facilitate the rise of human civilisation.

There is nothing unusual or remarkable about the Modern Warm Period other than that the academic stratigraphers of the ICS Sub-Committee for the Quaternary happen to live within it.

But the ICS Interprets Pleistocene Data Differently…

According to the ICS, and with the approval of the IUGS, the Pleistocene Epoch (or Pleistocene Ice Age) finished, terminated and collapsed forever 11,700 years ago (0.0117 Ma), to be replaced by the Holocene Epoch. These august bodies must therefore consider that the Holocene interglacial is fundamentally different from the numerous interglacials that preceded it.

To be logically consistent, if the Holocene is a separate Epoch within the Quaternary, then all previous Interglacials and Glacials of the Quaternary must be judged as Epochs also. With 90 or more Epochs, the Quaternary would then contain more than three times as many Epochs as all other 26 Periods of the stratigraphic record combined. An absurd proposition. And the Quaternary is not finished yet.

In this dilemma, the ICS appears to be trapped in an epistemological maze with no clear roadmap to follow.

Because the sediments are so recent, stratigraphers of the Quaternary have a plethora of available evidence enabling them to create ever finer subdivisions of geologic time. But that is no excuse to elevate these micro-divisions to the status of “Epochs”. Otherwise, we would have to conclude that an Epoch of the Quaternary is equivalent to a mere sedimentary horizon of the Paleozoic. If there is to be logic and meaning to standard terms for the division of geologic time, consistency of definition is surely vital.

But could the ICS be correct in concluding that the Pleistocene Ice Age ended 12,000 years ago with the beginning of the Holocene? It will be another million years before we can be 100% certain of the answer to that question. But we don’t need to wait that long. Based on the evidence presented, I am more than 90% certain that the glaciers of the Pleistocene will return. Whether that be in 500, 1000 or 2000 years’ time, we just don’t know.

The members of the ICS apparently consider that, starting from the time of the cultural Neolithic Revolution (made possible by the benign climate of the early Holocene), humans have caused sufficiently large changes to global sedimentary processes and fossil assemblages to justify raising the status of the Holocene from merely the most recent of the many Pleistocene interglacials, to a unique stratigraphic Epoch in its own right.

Whatever the reasoning of the ICS, this is a controversial and debatable proposition. As the late, great, Carl Sagan wrote in 1979: “Extraordinary claims require extraordinary evidence”. No such evidence has been presented.

But it Gets Worse…

Astonishingly, in 2019, the ICS made another proposal to their governing body, the IUGS. They advocated the creation of a brand-new Epoch to succeed the Holocene Epoch. This Epoch was to be called the “Anthropocene”, a neologism cobbled together from two Greek words meaning roughly: “The New Age of Man”. It was proposed that the Anthropocene started around 1950AD.

This is equivalent to the fond hopes of 1946 that the establishment of the United Nations would lead to a new epoch of Global Peace and Stability (Pax Americana?) that would last for 1,000 years.

To their credit, in 2019, the IUGS, in a near-unanimous vote, rejected the Anthropocene proposal of the ICS.

I strongly suspect that the stratigraphic proposals of the ICS concerning the Holocene and Anthropocene were influenced by the current fashionable scientific meme that the effects of modern human activities, including CO2 emissions, are strong enough to overwhelm all other terrestrial and extraterrestrial forces that have controlled temperature, sediment deposition and life around the globe for billions of years.

Back to the Future…

Our remote descendants, as they shiver in their caves, may well think otherwise.

The post The Happy Holocene appeared first on Roger Marjoribanks.

The Copper Wars, called by some the Battle of Butte, took place from 1898 to 1906 between the Anaconda Copper Company and companies owned by Fredrick Augustus Heinze. One of the minor but significant players these wars was young Anaconda geologist Reno Sales (1876-1969).  In his eighties, Sales wrote a book about his experiences int the war called Underground Warfare at Butte (1964). Much of this post is based on that book. Background details to the conflict are taken from “The Battle for Butte” (1981) by Montana historian Michael P Malone.

Butte Montana

In the late summer of 1864, a group of prospectors discovered placer gold in the alluvial gravels of Missoula Gulch, a tributary of Silver Bow Creek in NW Montana. A rush ensued, but the gravels were thin and soon exhausted and the gold miners moved on. But swarms of quartz veins, up to 30m wide and stained with secondary oxides of iron, manganese and copper, had been noted at surface over an area of 15 km2 throughout Butte Hill which overlooked Silver Bow creek to the north. Within 10 years, shafts sunk on these veins had discovered rich silver and lead ore and a new rush began.  Butte Hill gave its name to an emerging and rapidly-growing boom town based on silver and lead mining.

One of the early pioneers of the silver boom at Butte was Marcus Daly. Daly was born in 1841 near Ballyjamesduff in County Cavan, Ireland.  As a 15 year old he joined the Irish diaspora escaping the potato famine, arriving penniless and alone in New York in 1856. Travelling west, he learnt his trade as prospector and underground miner on the California goldfields and the silver mines of Nevada and Utah.  In 1880, moving to Montana, Daly paid for $40,000 for the most productive silver vein on the field – the Anaconda. Two years later (1882) a crosscut from the 300-foot level of the Anaconda opened a 10 m wide vein of high-grade chalcocite (copper sulphide: Cu₂S). Grades averaged 12% Cu, but locally reached 55% (Malone, 1981). Soon a new rush based on copper mining began at Butte as more and more bonanza copper veins were discovered and developed through numerous shafts and dozens of individual claims. All this coincided with a booming demand for copper as America began to electrify at the end of the nineteenth century: there were vast fortunes to be made at Butte.

The Butte mineral field was, and possibly still is, one of the biggest metal concentrations on the planet. Up to 2013, it had produced 9.8 million tons of copper along with very substantial tonnages of Zinc, Manganese, Lead, Molybdenum, Silver and Gold. As at that date, a resource of 4.9 billion tons of 0.49% Cu and 0.033% Mo remained to be mined (Houston and Dilles, 2013). Mining of copper and molybdenum in the Continental open cut continues to this day.

Figure 1: Geology of the Butte District. Orange lines are the mineral veins, blue lines are faults. L is the Leonard Shaft, Tw the Tramway Shaft, Ra the Rarus Shaft, Pe the Pennsylvania Shaft and A the Anaconda Shaft. Figure 3 from Houston & Dilles, Economic Geology, v108, 2013.

Figure 2: An example of detailed underground mapping at Butte by Anaconda geologists: the 1200′ underground level of the Pennsylvania mine. From Reno Sales 1914 Memoir: “Ore deposits at Butte, Montana.” 

The Apex Law

The United States Law of the Apex (or Apex Law, or Apex Rule) was established and defined by the US General Mining Law of 1872 and applies to Federal public lands, located mostly in the Western States. It was based on the idea of winner take all. If you own the highest point – called the apex – of a mineralised vein, the Apex Law allows you to mine it down dip, even beyond the point where it passes at depth through the projected vertical boundary of your claim into an adjacent property. The apex holder can continue mining down the dip of the vein past his claim boundaries, but not along its strike (i.e. the horizontal extensions). Where the claim is rectangular with long sides parallel or sub-parallel to the vein strike (as would normally be the case) then the law states that mining at depth must be constrained within the projected vertical planes that define the two short sides of your claim: provided these sides are parallel and not divergent, and provided your claim was registered first. This is called your Extralateral Right. A Sub-Fault Apex is created where upward continuity of a vein ends against an intersecting fault plane. “Continuity” is the key word here.  If the essential character and continuity of a vein can be demonstrated across a displacing fault, then the apex of the vein is the apex of the vein on the hangingwall of that fault and there is no sub-fault apex on the footwall.

What could possibly go wrong?

This absurd law, still in force today although seldom used, was written to legalize and codify what had become accepted mining practice in the Comstock silver district of Nevada – traditions probably brought there by immigrant Cornish miners and reflecting mining practice going back to pre-Roman times. But in the Comstock District (or in Cornwall for that matter) veins are usually discreet with relatively constant strike and dip. In Butte, by contrast, the mineralised veins form anastomosing swarms over an area of 15 km², with variable strike and dip, and are cut and displaced by several shallow-dip normal faults (figure 1).

By 1887, virtually every surface vein had been located and pegged in the Butte area with hundreds of claims, dozens of head frames and numerous smelters. With bonanza grades and millions of dollars at stake, it is not surprising that the Apex Law provided the source for endless litigation, illegality and corruption. This led directly to the Copper Wars. But an incidental good that came from this sordid time in mining history was the genesis of detailed geological mine mapping.

The Anaconda Copper Company Consolidates the Field

By 1898, a round of acquisitions, financed by East Coast money men, led to extensive consolidation of ownership with the Amalgamated Copper Company becoming the dominant player on the field. Later, the Amalgamated Copper Company changed its name to the Anaconda Company. To avoid confusing the reader with a multiplicity of company names, I use Anaconda Company or just Anaconda for the remainder of the essay. You will find more detail on the corporate structure at Butte in footnote  [1].

One of Anaconda’s first steps was to set up a well-resourced geology department to provide accurate surface and underground geological mapping of the vein systems and enclosing rocks. This was not just to provide information for mine development, but to arm themselves with exact scientific data to use in the litigation consequent on the Apex Law. The geology department was set up and headed by Horace V. Winchell. Among his first hires were rookie geologist Reno H Sales (in 1900, from Columbia School of Mines, New York City) and David M Brunton (an experienced Canadian geologist, inventor of the eponymous geology compass). Between them these three worked out the essential methods and procedures for accurate underground mapping of Butte’s geology. This involved the meticulous observation and measurement of all lithology, structure and mineralisation seen on underground rock faces, and the plotting and interpretation of the data on stacked Level Plans and Cross Sections throughout the mine. This scientific approach had never been attempted before at this scale or in such detail.

Reno H Sales in 1939

A New Player Comes to Town

In 1898, at around the same time as the Anaconda company was being formed, a new and colourful character entered the scene at Butte. He was Frederick Augustus Heinze (or Fritz, to his friends).

Frederick Augustus Heinze in 1910

The son of immigrant German/Irish parents, Heinz was educated in both the US and Germany and graduated a mining engineer/geologist from Colombia School of Mines – the same school as Sales.  After a brief stint working as a Mining Engineer with the Butte & Montana Company, he resigned and, with borrowed money and an inheritance of $50,000, created several companies to buy up a portfolio of many of the scattered small mines, smelters and claims in the district that had yet to be absorbed by Anaconda. This group were then amalgamated in 1901 into the United Copper Co. Where the Anaconda Company had set up a geology department  to help defend their rights under the Apex Law, United Copper set up a legal department of 37 lawyers to achieve the same end. They were led by Heinze’s able lawyer brother Frank, and he set to work aggressively pursuing Anaconda through the courts for all real or imagined rights.

Heinze promoted himself and United Copper as the champions of the little miner against the creeping hegemony of the “evil” Anaconda and their Wall Street capital backing. He bought and edited a local daily newspaper – called the Reveille – which constantly attacked Anaconda and its senior employees, accusing them of corruption, perjury and other illegal activity. Butte locals referred to this paper as the Reviler, Sales called it a smear sheet.

Full page cartoon in the Butte Revielle.  It depicts a sinister Reno Sales as a burglar lurking in a dark alley. In his hand is a gladstone filled with “Tools, False Affidavits and Perjuries”. Figure reproduced from Sales, 1964.

Heinze financed the electoral campaigns, at local, state and Federal Level, of politicians and judges  whom he thought would be favourable to his cause (Malone, 1981). Heinze also used his considerable oratorical and demagogic skills to address crowds of miners from the Butte Hotel balcony, or from the Courthouse steps. He became a hero to his employees, reducing their working hours from 10 to eight hours per day whilst maintaining their daily rate of $3.75 – Anaconda were grudgingly forced to follow suit. District Judges William Clancy and Edward Harney, who were indebted to Heinze for their election (Malone, 1981) were particularly important to Heinze as they presided at the Silver Bow County Court where rulings on the application of Mining Law in much of the Butte District were given. Judge Clancy’s rulings in particular were so biased in favour of Heinze that it is hard not to believe there was a direct financial connection between them (although Sales is careful to make no claim of outright corruption).

District Court Judge William Clancy. According to Sales, his trident beard was usually decorated with samples from his morning’s breakfast. Image from Montana State Library. 

Through the period  1898 to 1906 there were literally hundreds of individual battles between the two companies, and they were conducted not just in the courts and but as physical confrontations between miners at the rock faces underground. Many of these disputes ran simultaneously: some lasted, unresolved, for the full eight-year period of the conflict. Writing in his old age in 1964, Reno Sales was intimately involved in most of these battles and describes them in great detail in his book.

I retell the story of just two of these battles, to indicate the nature and scale of the conflict.

The Battle for the Pennsylvania

The most productive claim owned by United Copper was the Rarus. Ore coming up the Rarus haulage shaft provided the main feed for their concentrator and smelter located on the claim. The Rarus claim contained a system of interconnecting veins which dipped mostly south at a steep angle and so, with some wishful thinking, might pass at depth into the adjacent Pennsylvania and Michael Devitt claims of Anaconda (figure 4). The future of the small Rarus orebodies, and of its ever-hungry smelter, therefore critically depended on proving before a Judge that Rarus had extra-lateral mining rights under the Apex Law into the Anaconda ground.

Figure 4: A portion of the Butte mineral field showing claims held around 1901. The claims shaded with dots were owned by Anaconda. The Rarus claim (with no shading) and its extension to the SE (diagonal lines) were owned by Frederick Heinze and the United Copper Company. Other parties owned the  unshaded claims to the west. Figure reproduced from Sales, 1964. 

The situation was complicated by the large, northeast trending, shallow northwest-dipping, Rarus Normal Fault that ran through all these claims and displaced veins in the area by up to 120 m. The Rarus Fault was by then well-established through geological mapping – both at surface by the United States Geological Survey (USGS) and underground by the Anaconda Company. The Rarus veins lay on the hangingwall of the fault: the rich Pennsylvania and Michael Devitt veins that Heinze coveted were on the footwall. However, the direction of throw on this fault made it virtually impossible that the Rarus veins ever were continuous with vein systems of Michel Devitt and Pennsylvania. The The only way for Heinze to establish extra-lateral rights was to go to court and deny the existence of the Rarus Fault. To establish this, Heinze was able to obtain (“buy”, might be a better word) the testimony of a series of mining “experts” – one of them a former USGS geologist who, in that role, had put his name to the USGS geological map portfolio of the district!

Now, as it happened, the Michael Devitt claim lay outside the jurisdiction of Silver Bow County, so Heinze had to make his case before a Judge sitting in the Federal Court at Helena (the Capital of Montana). But, for his claim on Pennsylvania, he was able to make his case before his good friend, County Court Judge William Clancy. With a long line of expert witnesses for both sides, these court cases took weeks to resolve and were expensive for both parties. Unsurprisingly, Federal Judge Hiram Knowles rejected Heinze’s petition. Judge Clancy, on the same evidence, and by a stroke of the judicial pen, removed the Rarus Fault from the equation and granted Heinze extralateral rights to Pennsylvania. Heinze supporters claimed that Judge Knowles was a former employee of Anaconda, but there was no evidence to support that.

With appeals, supplementary legal claims and counterclaims and political maneuvering at both Local and State level, the Michael Devitt dispute went on for several years. Throughout that time United Copper were mining and hauling to surface through the Rarus shaft huge tonnages of ore illegally mined from both the Michael Devitt and Pennsylvania properties. Injunctions were issued, mine inspectors appointed. There were visits by US Federal Marshalls. Derisory fines for contempt of $20,000[2] were imposed on Frederick Heinze [3] and $2000 and $1000 respectively on his Chief Engineer Alfred Frank and the Rarus Mine Foreman Josiah Trerise. Heinze paid no heed to these legal impediments and continued to mine Anaconda ore.

So it came about that throughout the year 1903 both Anaconda and the United Copper were mining ore within the Pennsylvania Lease between the 400’ and 1000’ levels. The mining levels of the Rarus and Pennsylvania mines differed by 50’ in elevation. Both Anaconda (Pennsylvania) and United Copper (Rarus) sought advantage by advancing drifts[4] above the level of the opposition in order to  extract the ore first. Almost daily, Pennsylvania workings would break into the workings of Rarus, and vice versa. When this happened, the openings were vigorously defended by opposing groups of miners, using high pressure water hoses, throwing rocks and smoke grenades  or blowing lime. Strangely, according to Sales, the miners regarded all this as something of a game, and confrontation seldom continued after they returned to surface. But it would not stay a game for long…

Figure 5: Fighting in the Pennsylvania Mine in 1903. Reproduced from Sales, 1964.

But it would not stay a game for long…

By October 1903, all attempts by Anaconda to gain access to Rarus workings so that they could document their illegal ore extraction for use in Court, had failed. With the approval of the Federal Court, Anaconda then commenced a raise[5] from the Pennsylvania 600 level to intersect the United Copper stopes on the Rarus 800 level (6).  The raise would provide Anaconda with their own access to the illegal United workings (see figure 6).  When Pennsylvania raise broke through into Rarus 800, Rarus miners tried to stop access by tipping mine waste into the new shaft and lighting large fires of rubber and leather where a downdraft would drive the fumes into the shaft and the Pennsylvania workings below.

Figure 6: The scene of the crime (not to scale).

Early on New Year’s day 1904, thinking the Pennsylvania mine would be deserted due to the holiday, Rarus miners lowered a large box of dynamite down the shaft and detonated it remotely. But although the Pennsylvania was quiet, two miners – Frederick Divel and Samuel Olsen – were working that morning on the 600 level. They had been given the special task of erecting an airtight wooden bulkhead near the foot of the shaft to block the noxious fumes of burning rubber. The blast from the explosion killed Fred Olsen instantly. Sam Divel was horribly wounded and died a few hours later.

It is hard to escape the conclusion that the dynamiting of the Rarus shaft was done with the full knowledge and probable instigation of Rarus management. However, at the subsequent Coronial Inquest, all employees of the Rarus Mine, from the foreman to lowest miner, swore on oath they knew nothing of the tragic event. Thomas Thyack, the Rarus Shift Boss who was on the level at the time of the explosion could not (or would not) give the names of the other miners present on the level because, he said, he only knew them by their first names. Attorney Peter Breen (United Copper) and Attorney L O Evans (Anaconda) were only prevented from coming to blows in the court by the intervention of the Coroner. The Jury’s verdict was manslaughter by person or persons unknown. Despite Anaconda’s offer of a $5000 reward for information, no one came forward, no one was ever charged with the crime.

Figure 7 Death of Fred Olsen

The Battle for the Leonard Deeps

Among the many scattered small claims bought by Heinze in his initial acquisition phase was the tiny 1.7 ha (4.2 ac) Minnie Healy.

To the south of Minnie Healy was the Tramway Claim in which Anaconda had majority ownership and United Copper minority ownership, but there was an existing court injunction against either company mining the Lease.  The Tramway vein dipped north and was projected to enter Minnie Healy at depth. But Anaconda had the apex, and clear extra-lateral rights.

Immediately north of Minnie Healey were a group of claims wholly owned and actively mined by Anaconda. The ore was from the rich Coluso, Gambetta-3 and Leonard veins – which were amongst the most productive of the Butte field. These veins dipped steep south, converging below the 700’ level into a horsetail zone with outstanding tonnage potential (see Figures 2 and 7).

Figure 8: A vertical cross-section (view to west) of vein systems in the vicinity of the Minnie Healy claim of United Copper. Redrafted, with some additional annotation. From Sales, 1964

The Minnie Healy claim contained several small anastomosing veins with modest remaining copper reserves. These veins had variable but steep dips to the south, but there was no evidence that they might trend at depth beyond the vertical boundaries of the Claim. In spite of this, it is almost certain that the main reason why Heinze had bought Minnie Healey was to establish extralateral mining rights into the rich, adjacent Leonard-Colusa-Gambetta-3 vein system of Anaconda.  Heinze could be confident of a favourable outcome since was a case that would be heard before Judge Clancy

And so began yet another of the endless series of apex hearings in the Silver Bow County District Court.

As an expert witness for Anaconda, Reno Sales showed the court a geological section (figure 8) based on detailed geological mapping using the methods that had been developed and carried out by the Anaconda geological team over the preceding few years. Appearing for United Copper, their Chief Engineer Al Frank produced a “geological” section which showed a broad, fuzzy mineralised zone dipping north from the Minnie Healey to enclose the coveted Leonard-Coluso-Gambetta-3 deeps below the 700 level in the Anaconda ground. Franks’ “geological” section was based on little more than wish fulfilment. It omitted the Rarus Fault [7] whose existence, of course, would have been detrimental to his position. Frank’s interpretation of the geology consisted of a section with a single broad dash line showing the course of the vein systems across the two claims.  I have superimposed Frank’s “geology” as the broad purple dash line on Sale’s section (figure 8) .

The new geological science of accurate underground mapping won the day. Judge Clancy denied United Copper’s claim for extra-lateral rights and placed an injunction on their mining in the Anaconda ground. But in an absurd twist, he at the same time placed a similar injunction on Anaconda from extracting ore in their own mine from below the 700 level! Presumably, he thought this the Judgement of Solomon.

Although not quite the judgement he had sought, Heinze was undaunted. He reflected that what goes on underground is easy to conceal. An injunction to cease and desist only affects those companies who feel compelled to obey the ruling. With Anaconda excluded from the deep levels of their own mine, Heinze felt free to crosscut from Minnie Healey and commence illegal mining of the Coluso-Leonard deeps. As Anaconda subsequently found out when they eventually re-gained access to their mine, many thousands of tons of rich copper ore were removed. At the same time, in early 1904, Heinze constructed a secret crosscut to the south from the 1000’ Minnie Healy level and commenced to mine the Tramway vein, despite the previous Federal Court injunction against both Anaconda and United Copper from mining this vein.

Anaconda Wins the War

In February of 1906, Anaconda bought all the assets of Frederick Augustus Heinze with which they were currently in litigation (amounting to well over 100 active cases) for $10.5 million. United Copper retained some producing assets at Butte but became a minor player. Heinze took his money and left for New York with the intention of turning his great fortune (by then estimated at $25 million) into an even greater one. With his brothers Frank, Otto and Arthur, he set up a brokerage firm and acquired a bank. Through these they attempted to corner the all the stock in the United Copper Company so as to drive up the price and make a killing through the forced buying by short sellers (by that stage the Heinze brothers hoped to hold all the stock). But they miscalculated, the scheme failed spectacularly, and the brothers went bankrupt (8).  The scandal caused a run on a number of banks and instigated the great Wall Street crash of 1907 and the subsequent creation, in 1913, of the Federal Reserve System (Malone, 1981; King 2012).

Heinze was down, but not yet quite out. He continued as the main shareholder and principal of United Copper, but its share price, which had fetched $80 in its glory days, fell to 80 cents and went into receivership in 1911. F. Augustus Heinze returned to the west and resumed his specialty of apex litigation in the Coeur D’Alene district of Idaho. He died in 1914 at the age of 44 through cirrhosis of the liver.

In 1906, Sales succeeded Horace Winchell as the Chief Geologist of the Anaconda Copper Company (see Reno Sales biography, Perry & Meyer, 1968). Under Sales, the Anaconda Company became renowned for the excellence of its geological work. The quality of mine mapping for which North American geologists are known was a direct result of the foundations laid by Reno Sales and his colleagues in Butte around the turn of the 19th century. The geology department of the Anaconda Copper Company was one of the important factors contributing to its growth through the 20^th Century to become one of the world’s major mining houses.

Reno Sales was director of the geology department of Anaconda until his retirement in 1947. In his long career, he was awarded an honorary Doctor of Science degree from Montana State College (1935), the Penrose Medal of the Society of Economic Geologists (1939) and the Egleston Medal for distinguished engineering achievement (1942). He was President of the Society of Economic Geologists in 1937.

Reno Sales died in 1968 at the age of 82.

Some Final Thoughts

In 1906 the Anaconda Copper Company was left in almost complete possession of the field at Butte and so, in that sense, were entitled to be called the winner of the Copper Wars.  Frederick A Heinze had surrendered the field:  but he left richer by more than ten million dollars and would not have considered himself a loser.  But winners get to write the history.  That history is a satisfying one of Good Guys v. Bad Guys, where the guys in the white hats win through in the end after years of struggle and that is the story I have retold here. But was Frederick Heinze entirely the one-dimensional, opportunistic, greedy rogue portrayed by Sales?  At the time, Heinze portrayed himself as a battler for the rights of miners, claim holders and small mining companies, threatened by a wealthy corporation with bottomless pockets. Even although Heinze’s main motivation was to build a wealthy corporation for himself, there is no reason to suppose that he was not sincere in his desire to improve the lot of miners. Undoubtedly, many in Butte during the nineteen noughties saw Heinze as their champion, and it is clear that his employees were fiercely loyal to him.  I suspect that Anaconda’s motives during the war were not always pure and their own methods not always ethical or legal. Heinze’s efforts to counter the technical presentations of Anaconda geologists before the courts may appear ludicrous, but we are seeing this through the eyes of Reno Sales – hardly an unbiased reporter. Heinze did not have the luxury of a well-resourced geology department to support him.

********

Personal note:

I was an employee of the Anaconda company from 1976 to 1985. In the Spring of ’77 I spent a week in Butte where, in a small down-town secondhand bookshop, I bought a copy Reno Sales 1964 Memoir, “Underground warfare at Butte”.

 Sources

King, Gilbert. September 2012: The copper king’s precipitous fall. Smithsonian Magazine. www.smithsonianmag.com

Houston R. A. and Dilles J.H.: 2013: Structural geologic evolution of the Butte district, Montana. Economic Geology, V108, pp 1397-1424.

Malone, Michael P 1981: The Battle for Butte – Mining and Politics on the Northern Frontier, 1864-1906. University of Washington Press, 281p

Meyer, C., Shea E. P., Goddard C. C., Staff: 1970. Ore deposits at Butte, Montana. In: Ore Deposits of the United States, Gratton-Sales Volume 2, AIME, pp 1373-1416.

Perry V. D. and Meyer C., 1970: Biography of Reno H Sales. In: Ore Deposits of the United States, Gratton-Sales Volume 1, AIME, pp xvii-xxiii.

Reno H Sales, 1914: Ore deposits at Butte, Montana. AIME Transactions v46, pp 4-106.

Reno H Sales, 1964. Underground warfare at Butte. Caxton Printers, 77 p.

Footnotes:

The post The Copper Wars of Butte and the Invention of Underground Geological Mapping appeared first on Roger Marjoribanks.

Field geologists have long known that the style and relationships of structures seen in a hand specimen, outcrop or drill core can mimic the style and relationships of much larger structures that formed during the same deformation but occur at the scale of a geological map or section. Since very large structures can seldom be directly observed, recognising these relationships has immense practical value when making a geological map or interpreting a drill section. The techniques are today generally known as the use of vergences and fractal (scale-invariance) relationships.  Vergence and fractal relationships are two separate but related things which will be defined in the sections blow and  an outline given of their application in practical field geology.

The idea of vergences was first enunciated in 1894[1] by the US Geological Survey Geologist Raphael Pumpelly[2].  According to Pumpelly:

 The axes and axial surfaces of minor folds of an area are congruent with those of the major fold structures of the same phase of deformation.  

This idea became known to several generations of geologists as Pumpelly’s Rule.  Although strictly only a theory of fold and axial surface vergences, the Rule came to be associated with the idea that the general style of all minor structures was likely to mirror that of the major structures with which they were associated. With the invention of Chaos Theory in the 1970s and 1980s this latter aspect of Pumpelly’s Rule was recognised as a particular example of scale-invariance – a characteristic of objects that form through the operation of non-linear physical laws (i.e. – all naturally formed objects).  Using the new mathematical language, geologists have taken to calling these relationships fractal (a better because more self-explanatory term is “scale-invariance”).  Few geologists today have heard of Pumpelly’s Rule: this is a great pity, for this is one area where geologists anticipated mathematicians by almost 100 years, and Pumpelly was one of the greats of 19^th century North American geologists. Here he is, in all his hirsute late Victorian glory:

Raphael Pumpelly (1832-1923). Eponymously famous for his Rule and the mineral Pumpellyite.

Vergences

An axial-plane cleavage is a penetrative planar surface which (to a first level of approximation) bisects the angle between the two limbs of folded beds. The line of intersection of any cleavage plane with any one of the folded beds is approximately parallel to the axes of all major and minor folds that are associated with that deformation.  On the illustration below, a folded bed is shown in grey and the cleavage as fine blue lines.

In the hinge area of the folds (the red-circled areas labelled 3 on the map), cleavage lies at a high angle to the beds; any minor second-order folds in the hinge area are symmetrical –  that is, their 2-D profile  shape has an “M” or “W” shape.  In the hinge region, bedding/cleavage relationship and fold shapes are symmetrical.  To the structural geologist, bedding and cleavage  has a neutral vergence.

Examples of vergence relationships across a major fold

On the figure above, observe how the cleavage on Limb 1 of the large mapped fold lies at a much lower angle to the bedding than it does in the hinge.  Compared to the relationships seen in the hinge, the cleavage on this limb is rotated to the left, in an anti-clockwise direction. Since in Latin the word for left is “sinister[3]” , this bedding/cleavage relationship is known as sinistral and described as having a sinistral vergence. Any minor second-order folds on this limb (parasitic folds) are asymmetric and also show an anti-clockwise or left-rotation sense of movement. Folds with this profile shape are known as sinistral folds. Such folds have a “S” shape so are also called S-folds. 

On Limb 2 of the major fold, the cleavage also lies at a relatively-low angle to the bedding, but in this case the sense of rotation is clockwise or to the right. Latin for right is “dexter”, so such bedding/cleavage relationships are said to have dextral vergence. Associated folds have a “Z” shape in profile and are known as dextral folds or Z-folds.

Fold hinges are much less likely to be exposed at surface than fold limbs -  there are good reasons for this as explained in the footnote below -[4].  However, by carefully observing and recording vergences on the exposures of the limbs, the opposed patterns of sinistral and dextral vergences across the mapped area enable the position of major unobserved fold hinges to be determined. In addition, measuring the plunge of minor folds and bedding/cleavage intersections will give an indication of the plunge of the major structure.  The style of minor folds in outcrop will also give an indication of the style of the larger fold with which they are associated.  This is an example of a fractal relationship rather than vergence, and will be described below in a separate section.

It is important to note that the sense of vergence given by the asymmetry of fold shape bedding/cleavage is, by convention, determined on the view the structure from above – i.e. a view looking down the fold axis or down the line of intersection of the bedding and cleavage. Since this is the way that geologists normally view an outcrop, the convention usually creates few problems. However care needs to be taken when making a geological map of an underground mine level where most available exposure is on the roof (called backs) of the mine opening. A dextral or Z-shape fold seen on the backs (necessarily looking up-plunge) needs to be shown on a map of the mine level as its mirror image - a sinistral or S-shaped fold: maps always show the view from above (another convention). 

Vergences can be used to great effect when logging drill core, as illustrated in the figure below.  If the core is oriented, the vergences of minor folds and bedding/cleavage can be interpreted in exactly the same way as vergences seen in outcrop. Vergence information is used to determine a vector pointing up or down the hole towards the position of the hinge of the major anticline or syncline in that hole. On the trace of the hole on a drill section, the vergence observations from the core (the vectors) can be shown as small arrows beside the hole trace that point up or down the hole.  Such arrows greatly aid interpretation of the section.

In the illustration below, the vergence arrows plotted on the drill section point have been drawn to point towards the major anticlinal axis in the hole. Some structural geologists like to use arrows that point towards the syncline axis. This is because, when logging sedimentary rocks, a direction of younging – either up the hole or down the hole – can often be determined from sedimentary structure.  If arrows are then plotted on the section to record younging direction, they will also point to towards the synclinal axis [5].   By combining arrows derived from vergence observations that point to the syncline, with younging direction arrows that provide the same information, there is a synergy from two different sources of knowledge that greatly aids interpretation. Needless to say, different kinds or colours of arrow are used on the plot to distinguish the two differently-derived vectors.

How vergence observations from oriented drill core can be used to help determine the position major fold axes on the drill section.

If the core is not oriented, vergence information is lost because there is no way of knowing whether the view of the structure is down-plunge or up-plunge since the view of any structure will change as the core is rotated. However, even in non-oriented core, it is possible to distinguish fold limbs (with low bedding/cleavage angles) from fold hinges (high bedding/cleavage angles) and this is valuable information to help in locating major unseen structure in the core.

Fractals or Scale Invariance

Scale invariance refers to the way that structures resulting from a single tectonic event exhibit similar styles of deformation at scales that can range from the microscopic to that of a regional map.  Style refers to general aspects of the appearance of structures such as tightness, degree of irregularity, and asymmetry (but not the sense of asymmetry, that is not a fractal attribute) and so on.  Since the characteristic essence of the shape of any natural object, regardless of its size, can be expressed as a fractal dimension, scale invariance relationships have come to be called fractals by geologists. A fractal dimension is a dimension between 1 and 2 if dealing with lines on a plane figure such as a map or section, and between 2 and 3 if dealing with a solid object.  (I have attempted a definition of fractal dimension in footnote 6, below, but the subject is complex and really requires a whole post of its own see Link).

The word fractal has today become poplar amongst geologists, and has superseded the term Pumpelly’s Rule (which has priority but is a bit of a mouthful) and scale-invariance (which is a more accurate term and self-explanatory); perhaps this is because “fractal” is a short and easily-remembered word which trips off the tongue and sounds “sciency” and modern -  and few people know what the word actually means.[6].   I fear the profession is stuck with fractal.

examples of fractal relationships at various geologically-realistic scales from regional map to thin section, are shown in the illustration below.

Examples of scale-invariate, or fractal, relationships across a range of geological scales

If I were to parody Jonathon Swift, I might say:

So, Geologists observe, a fold,

Hath smaller folds that on limbs prey,

And these have smaller yet to parasite ‘em,

And so proceed ad infinitum.

Of course, in Nature, self-similarity is never literally found through an infinite range of scales.

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The sub-divisions of the Paleozoic. Click for a sharper image.

The science of geology was born in the last few decades of the 18^th and the first few decades of the 19th centuries. Its development was one of advancing ideas and knowledge, but the new knowledge above all was driven by the progressive improvement in geological method, and in particular a way of proceeding through the production of ever more refined geological maps. In this time the great geological Periods – the Primary the Secondary and the Tertiary were defined and named by the pioneer academic geologist Charles Lyell. These primary divisions remain today, although the Primary and Secondary of Lyell are today known by their modern names of Paleozoic and Mesozoic and the Tertiary has been downgraded and subsumed into the Cainozoic.  In the 50-year period from 1830 to 1880 the subdivisions of the Paleozoic were established and named by the giants of early field geologists through heroic campaigns of field work, geological mapping, controversy and compromise. It is an oft told and fascinating story. But one more re-telling can do no harm.

The 18th century practitioners of geology were moneyed gentlemen with time on their hands who introspected from the comfort of their living rooms and made wide ranging deductions from specimens of rocks, minerals and fossils.  These they bought from quarrymen or commercial collectors to fill their cabinets of curiosities. As gentlemen, did not do field work, or where they did, it was occasional and limited jaunts.  In England the way forward was shown by William “strata” Smith, no gentleman but the son of a blacksmith and a self-taught land surveyor. Smith was very much the field man who, self- funded and self-taught, travelled the roads of England for over 20 years in order to produce (1815) his great map of the geology of England. It was the first geological map in the world of such a scope and ambition. In order to compile his observations and interpretations, Smith used the best available topographic maps as a base – in his case sheets at 5 inches to the mile (1:132,000) specially engraved for him on copper plates by the leading cartographer of the day, John Carey. Smith applied to join the Geological society of London (the first geological society in the world) but was rejected because he was an uneducated outdoor manual worker of inferior social class. But that did not stop the learned Society from plagiarizing Smith’s great map of England and re-publishing it, at a cheaper price, under their own name [1]. Smith was forced into bankruptcy and spent time in debtor’s prison.

William “Strata” Smith

With the end of the Napoleonic wars, old 18^th century prejudices against field work were beginning to fade and the heroic age of geology began.  Smith, now happily pensioned off in retirement at Scarborough, came eventually to be acknowledged as the “father of English geology”.  The study of Geology became the cutting edge discipline of the field of science. It was the area of new scientific knowledge that caught the imagination of every educated man and woman, and for this brief period, Geology occupied the slot in popular imagination that, say, molecular biology or fundamental physics does today. This was true all over Europe and North America, but in Great Britain – a compact country with good communications, increasing availability of detailed topographic maps, a good range of rocks and perhaps, above all, a wealthy middle class, was where most of the new advances at this time were made. The heroes of this great age of geology were self-taught, often independently wealthy men. They had not completed courses in geology at university:  there were none. They believed in application and intellectual rigor combined with getting out into the field to see for themselves. Following Smith, they believed that making a geological map was the best way to record their observations and work out their ideas.   

Two of the greats of this time were Roderick Murchison and Adam Sedgwick. Before their arrival on the scene, all the easy bits of English geology – the regular, fossil-rich strata that succeeded, layer upon layer, from the Carboniferous up to the Cainozoic – had been essentially mapped by William Smith and published in his historic map of England and Wales. But for Smith and other stratigraphers of the late 18^th and early 19^th century, the rocks lying below the Carboniferous (Coal Measures, they called them) were difficult – they had few fossils, were metamorphosed to varying extent and much folded and faulted. Such rocks occupied the mountainous areas in the north and west of Great Britain and were lumped on contemporary maps into one grey and amorphous mass. They were generally known as the Greywacke Series.

Sir Roderick Impey Murchison

Roderick Impey Murchison (1792-1871) was a Scottish Highland gentleman who, in his youth, had joined the army and fought in the Peninsula War against the French. On discharge, he married a rich heiress and took to country pursuits.  After a few years, when killing foxes rather than Frenchmen began to pall, he had the good fortune to meet the early geological theorist, Charles Lyell. Lyall persuaded him to take up geology, then a rapidly developing scientific craze.  After apprenticeships in the easy rocks of the south of England, and the somewhat more complex rocks of the Alps, Murchison decided to tackle the outstanding problem of the day: the old greywacke series rocks that lay beneath the Coal Measures.  As far as anyone knew, these rocks could be the oldest on earth and contained the oldest fossils.

Murchison was a demon for field work – he climbed mountains, walked stream courses, covered hundreds of miles on foot, on horse or by coach. He started work in Shropshire on the border of England and Wales. In the Welsh borders, coal measures (i.e. Carboniferous age rocks) often sat directly on top of the greywacke series.  He mapped the old rocks westwards into Wales, placing them in a new geological period which he called Silurian after a long-extinct Welsh tribe.  Murchison’s major work “The Silurian System” was published in 1839.

Murchison went on to become the outstanding figure in 19^th century British geology and geography: President of the Geological Society (now reformed from its early days as a dining club for rich, dilettante London snobs); Fellow of the Royal Society, Director General of the British Geological Survey, first President of the Royal Geographical Society.

The Reverend Professor Adam Sedgwick

The Reverend Professor Adam Sedgwick did not set out to be a geologist either. He took a degree in Mathematics at Trinity College Cambridge (1808), and subsequently Holy Orders (1817). But in 1818, somewhat surprisingly – never having previously done any geology – he was appointed to the post of Woodwardian Professor of Geology at Cambridge. As he himself said on his appointment: “up till now I have never turned a stone.  Now I will leave no stone unturned.”  He was as good as his word: Sedgwick was an energetic and charismatic character, and apparently a brilliant lecturer (one of his students was Charles Darwin). He discovered in himself a passion and talent for field work.  By 1830, having established his geological credentials, he too decided to apply himself to the problem of the greywacke series. Starting in Central Wales, Sedgwick studied and mapped the hitherto intractable metamorphic rocks – calling them the Cambrian System – a name he coined from the old Roman term for Wales.  Sedgwick worked his way east, towards England, mapping Cambrian Rocks as he went [2].  Somewhere in mid-Wales he passed Murchison, mapping his way west and calling all his rocks Silurian.  Thus began the great Cambrian-Silurian controversy. Murchison argued that Sedgewick’s Cambrian should be seen as a sub-division of his Silurian System: Sedgewick argued the Silurian was a sub-division of his Cambrian. The two men were polite to each other and even published a joint paper on the subject in 1835. Neither would concede. To the Reverend Sedgwick, the Cambrian contained the oldest rocks in the world (well, in Great Britain, at any rate, but in the 19th century the British often conflated the two) and so might contain evidentiary record of Creation [3] - biblical Genesis itself.  No frocked Anglican cleric would easily give up priority in such an area.

The controversy over the Cambrian-Silurian boundary was not resolved for over 40 years.  The problem was that there were comparatively few fossils, and the geological maps of both Sedgwick and Murchison were too small-scale and interpretational to show relationships of units across wide areas of complexly deformed terrain. The man who resolved the Cambrian-Silurian problem was another self-taught geologist – an English/History schoolteacher called Charles Lapworth (1842-1920). In his summer holidays Lapworth virtually invented detailed large-scale outcrop mapping. He was able to do this because the Ordnance Survey of Great Britain was by now producing good coverage of very detailed topographic maps at a scale of 6 inches to the mile (approximately 1:10,000). This provided an ideal mapping base and was a resource not available to either Murchison or Sedgwick (or Smith, for that matter). Working in this detailed way in the Southern Uplands of Scotland and using a finely graduated series of evolving graptolites as indicator fossils [4] occurring through a thin sequence of black shales, Lapworth was able to show (1879) that a third major sequence could be placed between the Cambrian of Sedgwick and the Silurian of Murchison.  He named this new Period the Ordovician, after yet another extinct Welsh tribe.   The Ordovician was quickly adopted in Great Britain, but it would take until 1960 before it was officially recognised by the International Commission of Stratigraphy. Lapworth went on to become the foundation Professor of Geology at the University of Birmingham. Here he is in his professorial days :

Charles Lapworth leads a party of geology students into the field. I am pretty sure he is the guy in the middle of the front row holding a map or clip board. From the clothing (suits, waistcoats, ties, long skirts, stovepipe and boater hats) the date is probably sometime in the early nineteen hundreds. Note the surprising number of female students.

In much of Wales and the Welsh borders where Murchison and Sedgwick worked, the Carboniferous lay directly on top of the Silurian with neat unconformity.  Elsewhere (particularly in the County of Devon) a whole conformable sequence of generally red sandstone (local name: Old Red Sandstone) occurred between the two Formations. This led to another protracted controversy, which this time pitted Sedgwick and Murchison against another early great of geology – Henry De La Beche [5]. This controversy eventually led to the definition of the Devonian Era between the Silurian and the Carboniferous, thus completing the tally of the periods of the Paleozoic Era. 

Except for the Permian.

By 1834 the Triassic (the first Period of the Mesozoic Era) had been named by German geologists, but the boundary between the Triassic and Carboniferous rocks (each with dramatically different fossil assemblages) was still undefined as – through much of Britain and Europe – this important contact lay within sequences of non-fossiliferous red sandstone (the “New Red Sandstone”).  Roderick Murchison solved the problem and, in so doing, defined the last and uppermost Period of the Paleozoic.  In 1841, accompanied by the French paleontologist Eduard de Verneuil, Murchison visited Russia and examined a thick sedimentary sequence of fossil-bearing rocks overlying Carboniferous rocks along the River Klyaz’ma in the Perm district west of Moscow.  From these observations he defined and named the Permian Period, the last subdivision of the Paleozoic Era. 

This post has already gone on too long. You can read about the “Great Devonian Controversy” in the fascinating book of that name by Martin Rudwick (published 2008). You will find more details of the Cambrian-Silurian dispute in “Controversy in Victorian Geology: The Cambrian-Silurian Dispute” by James E Secord (published 1990). For Murchison’s travels in Russia see the paper by Michael Benton (and others) “Murchison’s First Sighting of the Permian at Vyazniki in 1841″ (Proceedings of the Geologists Association, 2010, p 313-318).

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