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The Pollett River continues to carve and etch a path down from the Caledonia Highlands in Albert County, forming steep ravines and rapids. Cliffs 10 to 20 meters in height guide the river and forms several waterfalls within a relatively short distance. The river is named for Peter Paulet, a Mi’Kmag medicine man who lived near the mouth of the river in the early 1800’s.
Conglomerate Formation: At the eastern end of a chain of highlands, which begin near the city of Saint John NB, extends eastwardly through the Saint John county and finally terminates somewhat abruptly a little to the center of Albert county. The mean elevation of these heights in Albert County is not far from 800 feet rising at its extreme eastern end, in Caledonia and Shepody mountains to as much as 1200 to 1400 feet while that of the adjacent lower Carboniferous would not average more than 150 to 300 feet. The rocks composing this elevated tract consists largely of slates, usually either chloritic or talcose in character; and of various colors; but with which are associated at some point, thick beds of grit and conglomerate, also chloritic or talcose, and less commonly beds of pink or flesh-red felsite or petrosilex.
Their age have not yet been definitely determined, but from observations made upon the more westerly portions of the same belt, in Saint John and Kings counties, they would appear to belong to, what in previous reports, has been described as the Coastal Group, which is believed to be of pre-Silurian and possibly Huronian age. The Silurian Period occurred from 443 to 416 million years ago. It was the third period in the Paleozoic Era which followed the Ordovician Period and preceded the Devonian Period. The Huronion Glaciation or Makganyene Glaciation was a glaciation that extended from 2400 to 2100 million years ago, during the Siderian and Rhyacian periods of the Paleoproterozoic era.
Along the northern border of the metamorphic belt, and immediately adjacent to the Lower Carbonifirous Tract, which traverses the center of Albert County, the sedimentary rocks, which consist mostly of chloritic slates, are associated with large quantities of reddish and gray syenite, which, in addition to occupying considerable areas, may be seen penetrating the slates in numerous veins and irregular masses of greater or less extent. They are well exposed on the Pollett and Coverdale rivers, and are the source from which the materials of the the Lower Carbonifirous conglomerates, have been to a great extent, derived.
References: Report of Progress/Geological Survey of Canada and Wikipedia – Silurian and Huronian Periods
What is Conglomerate? /noun: kənˈɡlämərət / is a coarse-grained clastic sedimentary rock that is composed of a substantial fraction of rounded to subangular gravel-size clasts such as granules, pebbles, cobbles and boulders, larger than 2 mm or 0.079 inches in diameter. Conglomerates form by the consolidation and lithification of gravel. They typically contain finer grained sediment like sand, silt, clay or a combination of them, called matrix by geologists and are often cemented by calcium carbonate, iron oxide, silica or hardened clay. Conglomerate can have a variety of compositions. As a clastic sedimentary rock, it can contain clasts of any rock material or weathering product that is washed downstream or down current. The rounded clasts can be mineral particles such as quartz, or they can be sedimentary, metamorphic or igneous rock fragments which mean theye have been formed through the cooling and solidification of magma or lava..
Types of Conglomerate: Two recognized types are shale-pebble and flat-pebble or edgewise conglomerates. Shale pebble is composed largely of clasts of rounded mud chips and pebbles held together by clay minerals and created by erosion within environments such as within a river channel or along a lake margin. Flat-pebble consist relatively of flat clasts of lime mud created by either storms or tsunami eroding a shallow sea bottom or tidal currents eroding tidal flats along a shoreline.
Clast Size Conglomerates are often differentiated and named according to the dominant clast size comprising them. A conglomerate composed largely of granule-size clasts would be called a granule conglomerate; if composed largely of pebble sized clasts it would be called a pebble conglomerate; and a conglomerate composed largely of cobble-size clasts would be called a cobble conglomerate.
References: Wikipedia – Conglomerate
To claim this earthcache, send an email to the cache owner with answers to the following questions: (please don't add the answers to your log)
1. At Stage One, take some conglomerate in your hand and let me know if it's smooth or rough. In your own words, what would have made them that texture?
2. Determine the size of one of the conglomerate rocks you are holding. Why would you need to know the size of a rock to know if it's a conglomerate?
3. At Stage One, determine the type of conglomerate you see. Is it Shale-Pebble or Flat-Pebble? Why do you think so?
If you wish to add pictures to your log, they are very welcome but not a logging requirement. A great location to do so would be at the bridge. Find the coordinates below at Stage Two. Please don't post pictures at Stage One.
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