Are you archiving pictures and other primary historical sources and worried about what date
you should be using? Would you like to use the astronomical date calculator to give you a single integer for
your index? This is just a mockup on 1954 AD but I am scripting it.
Links to information or data without charge on natural and built heritage sites are placed on this gateway
in geographical or age context:
online maps are listed in the geographical montage
online field guides are listed in the age montage
government data sets are listed in the jurisdiction pull down
cultural societies are illustrated by the favourite icon of their web-site in the geographical montage
Regions that are adjacent have common cell boundaries, regions which are not contiguous don't
In the stratigraphic table above, regions that are adjacent have common
cell boundaries, regions
which are not contiguous don't. This came about as an
attempt to maximise the space available for text. If for
instance I had used hotpoints in a geographical projection
there would be a few near-invisible points on a white page.
This is composed from the principle that history is periods of quiessance
punctuated by change. Therefore artifacts in any archeological
record are not recording changes but rather the quiet
period before that change. Examples of this are the
heritage building that has survived urban renewal.
It is from the period before the activity. In this
way the record of history is similar to a stratigraphic
column. For in a stratigraphic column the periods of
quiet deposition are shown as formations separated by
the unconformities, that is periods of active erosion.
Where it is obvious, I have used technological events to puntuate the
periods in the table. This is the archaeological concept that inventions revise culture,
and I have also found this in my own experience with geological
computing: successful technologies are quickly adopted because they
are successful. I don't think anyone in history has enjoyed watching
their children die. If there is something they can change in their society
to prevent those deaths, the parents will do it.
The second principle of this table is also taken from
the geologists stratigraphic column. The regional scope
of the data set represented by the link is shown by boxes
and member sub regions by boxes inside the outer box.
Where I have had the chance to research a geological formation I have used a dotted line around the website icons. This is implemented a style attribute of the enclosing HTML <nobr> element, which to enforces that they always appear at the same stratigraphic level, no matter what dimensions are used for the browser window.
Each table cell
joining other table cells gives every boundary that occurs
geographically. For example South Australia has only boundaries with
Queensland, New South Wales, Victoria, Northern Territory and
Western Australia. The arrangement of the table cell therefore
describes the complete geographical arrangement of the sovereign entities.
In comparison the stratigraphic column boundaries are portayed as separated from the intervening strata (browse the style .precambrian in the ./gateway.css file) to imply the geological uncertainty, and a heavy dashed line is used for a eon which is only suggested.
The colours of the stratigraphic diagram match that used in the International Geological Timescale. These are implemented with named classes (for example class="mesozoic") in the
gateway.css file on this website. I have reserved
the style="anthropocene" (see the Tasman Sea cell) for what would be described as "natural resources" in the current day.
This is in
contrast with the class="built" for man-made heritage. Current jurisdictions are distinguished by a flag color
if there is not a unique ribbon of favourite icons. Where possible, the icons for a cultural instittution also give the link to web page for the index to the heritage web-pages shown in the stratigraphy (for example in the United States list).
Stratigraphic Boundaries are bracketed by the ages for the stratigraphic elements above and below (the description is given with the span element, so move the mouse icon over each number). This is a better representation of the accuracy than quoting with the precision of the defining technique. Each stratigraphic element is defined on all geological measurement, in informatics terms "a boolean AND", not just the most precise measurement. For a field work equivalent, think strata stops being one stratigraphic element when it becomes another stratigraphic element.
An HTTP-compliant algorithm for the stratigraphic time continuum
Perhaps in the table above, to make the page more pleasing, I could have
pasted a satellite image behind those hot-points, but I only
wanted to show the information I had, and not have
the reader focussing on a picture with
no factual significance. The result is ugly, as it looks like an
object model for a computer program, but it is quite compact.
If you cast your mouse across the regions and boundaries you will see that
they are captioned with titles.
The table also shows the Tau shaped time-space (+stratigraphic) continuum
model. From at least the archaeologist's point of view, the longitude direction
is aligned in the direction of time, with latitude at right angles. Longitude
only affects the last day of time and so all history sits below the nexus of
the two coordinates as in the diagram above. For an example, consider the
scene in the film "Independence Day 4" where the aliens have flying saucers
distributed around the globe hovering above the capital cities. Then in
unison they begin attacking. Subsequently, for an archeologist investigating
these ruins, he or she would have to adjust the time of day of the attack
based on the longitude of the devastated city to demonstrate that the
destruction occurred at the same instant. Otherwise, it would appear
that it occurred during the previous day through the night to the next
day. Then the title of the film would have to be changed perhaps to
'Independence Weekend 4' and I am sure Hollywood would never have made
that film. Since setting up this table, there was the devastating tsunami
in the the Indian Ocean, and this mathematical approach to the timing
of geological events proved practical
in firstly identifying where the epicentre occurred and then determining
which islands and villages were affected so the rescue teams could visit
them, as there wouldn't be the resources to visit every island at least in
the time required to prevent further death.
To maintain the density of the text links, and keep the principle
that every table data cell boundary represents a geographical relationship,
the columns of links have been spaced or separated into groups by the
unsorted list element "ul". Then by using the style attribute of "float" the
columns of links occur as if they were separate "td" elements. The "ul" element
is also conveninet for fading any background color (actually re-assigning the
color with the style attibute) to make the text easier to read.
I started the table structure, because there was nothing else I could
easily put on the Bigpond web site. I was re-assured that before
Smith invented the geological map (of Britain), members of the Geological
Society used tables to display lithology, I have found there are some extra
benefits I didn't forsee:
I like the latitude dimension across time because it gives me a
rough seriatum for environment of deposition, the warmer climates are
in the core, the cooler to the outer.
The column on the left gives me somewhere to write down the
dates of the geological time scale as memorandum for when dealing
with data from age dating techniques.
Not obvious unless you look at the source code
(in Microsoft Explorer View > Source) is that all the
links are stored sequentially and inherently there are rules
linking the position of the objects. What is used in the browser
to plot the table, we can reuse to navigate up and down the stratigraphic
column. For instance to jump a period you need to find the next <tr>
HTML tag. I can even enhance this process by exploting the 'class=' element in
each of the tags so that to jump a geological period I look for the HTML
tag '<tr class="period_boundary">'. So in principle I could
have been looking for an algorithm that will sort geographic and time
data together into an index that would be suitable for a table of an SQL
(structured query language) database. I have to think a bit more on this
after I have written out the rules for navigation buttons.
Authors and books about the history of mineral surveying
The development of mineral surveying has been covered by the several authors in the Name List on the Computers in Geology home page. What they have written is listed elsewhere, as suggested. I find reading books like these very comforting; as I don't get half the run around that these pioneers had to put up with. The journals listed below that discuss more recent innovation in the work.
As well as the references from the recommended authors,
The Geoscience Gateway is compiled by Grant Jacquier as a free service for individuals and organisations
interested in computer application for practical geoscience.
Material on the Geoscience Gateway may be freely published provided acknowledgement of the source is given. Please note any opinions expressed here are assuming general conditions that will not be valid for all cases. Therefore readers should seek professional advice on their particular situation before implementing any suggestions.