Wednesday, November 2, 2011

"Young Uranium" "This (Summerland) "meadow" was once a marsh, but has been drained for agriculture and residential construction."

UPDATE Nov. 5, 2011:   Hmmmm, it must mean something, that if one were to type in "young uranium" into Google, this blog is the first on the top of the "heap".    Which means that we have become complacent in the case of uranium.

 Strange all this exploration for a mineral (Uranium and Thorium) that can't be mined in British Columbia, when Gold is a bona fide commodity.....


Google Search Criteria wording of  "20 ppb MAC uranium summerland bc" came from here

 Several interesting hits from the search criteria above, like this one..... contained on page 95 of 1588 pages on all of the mines in British Columbia but its below the third hit that says this:  Show more results from gov.bc.ca

The ore reserves of the Blizzard deposit are estimated to be 2,200,000 tonnes grading 0.815 per cent uranium (0.214 per cent U3O8) at a cutoff grade of 0.021 per cent uranium (0.025 per cent U3O8) over a 1-metre interval. Conversion used for U3O8 to uranium is 0.848 (Canadian Mining Journal, April 1979). Assessment Report 7822 reports a total of 4736 tonnes U3O8 is in the deposit.
 There's a tremendous amount of information on the Blizzard site which leaves one wondering just how much more Exploratory work was required ..... lately.


Page 255  HYDRAULIC LAKE, TYEE, KETTLE   has this:  COMMENTS: Centre of deposit (Paper 1979-6).

And if you take the last portion of the last line.....  (Paper 1979-6) and place it in Google it gives you this:


A Brief Submitted to the Royal Commission of Inquiry, Health and ...

www.em.gov.bc.ca/Mining/Geoscience/.../Papers/Pages/1979-6.aspx
Health and Environmental Protection, Uranium Mining by the Geological Division
, Mineral Resources Branch. Paper 1979 - 6. View Entire Paper (PDF, 43.3MB) ...


The first uranium exploration in British Columbia recorded was in 1932. Since then exploration has been sporadic, with minor peaks during the late 1940's, mid 1950's, and late 1960's. During this period only one deposit was found of sufficient size and grade to be a potential mine, and British Columbia was considered by most geologists to be a mediocre terrain for uranium exploration.

Many classes of uranium deposits are known in the world and representatives of most of these occur in British Columbia. However, to date only the basal type and volcanogenic type have been shown to be potentially of such a size and grade to be mined.

 Kelowna  would be a good word to punch into the 1588 page document......


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 But  Google Search Criteria was  20 ppb MAC uranium summerland bc gave this hit too, fifth item down


 YOUNG URANIUM
R.R. CULBERT and D.G. LEIGHTON

 Abstract

Culbert, R.R. and Leighton, D.G., 1988. Young uranium. In: J.W. Gabelman (Editor), Unconventional Uranium
Deposits. Ore Geol. Rev., 3: 313-330.

Deposits of young (post-glacial) uranium are presently forming in a considerable variety of environments in Canada and the northern U.S.A. by interaction between soils or sediments and uranium-bearing groundwaters. The uranium tends to be loosely held, and as it is too recently deposited to have built up radioactive daughter products, concentrations are seldom detectable by  scintillometer. Young deposits are of apparent economic interest in view of their common occurrence, amenability to in-situ leaching and lack of radioactive components. They are of environmental interest because they form concentrations of poorly fixed uranium which surface in areas of agriculture or development, and finally they are of academic importance for what they can tell us of how uranium accumulates in a sedimentary
regime.


Snip

Our exploration during 1978 and 1979 found young uranium deposits in southern and northern British Columbia, in the Yukon, in the maritime provinces and in the northwestern U.S.   Reports of strong accumulations of young uranium have also been made from the Canadian Shield (Coker and DiLabio, 1979), Scandinavia (Armands, 1961) and Russia (Kochenov et al., 1965 ), as well as from a number of non-glaciated areas.

Levinson and Coetzee (1978) reviewed the implications of radiometric equilibrium in the surficial environment for radiometric uranium exploration. Surficial uranium deposits were discussed and many described in the report of the International Atomic Energy Agency Working Group on Surficial Deposits (IAEA, 1984). This paper will rely heavily on data from the Okanagan area of southern British Columbia.  In part this is because these deposits were among the first recognized and are hence better known. More importantly, this information has been made public during reports to the B.C. Uranium Inquiry Commission and the B.C. Ministry of Public Health ( Culbert, 1980) and by a preliminary extraction feasibility study for selected deposits tabled before that commission (Hunkin Engineering, 1979). This exposure and the subsequent ban on uranium exploration in British Columbia have removed any question of privileged information.

Before proceeding with classification and descriptions, it should be noted that all deposits have been sampled by extendable hand augers using half meter sampling intervals, so that cross-sections show only the coarser variations in uranium content.   In converting from parts-per-million uranium to actual tonnage of U30s (or pounds per unit area), it is necessary to consider the insitu density of (dried) sediment. This varies all the way from 1.6 g cc- 1 or more for some saline clays to less than 0.5 g cc-1 for organic ooze or sphagnum. In general, inorganic sediments tend to be over 1.0 g cc- 1 while the usual organic materials run somewhat under unity.

Classification and examples

The following classification (Table 1) is based on the type of water involved in a deposit and on the type of trap. It is not being proposed as a formal classification system for young deposits, but has proved useful both in discussion and in exploration. The classes are only descriptively defined, and tend to grade into one another.
Furthermore, the number of deposit types and their relative importance are likely to change as exploration continues.

Closed basins

Hydrologically closed basins tend to become hypersaline, with minimal plant growth. Upward movement of groundwaters toward the surface (evaporative pumping) may therefore transport uranium without reduction to concentrate it at the surface. The example (Fig. la) from Wow Lakes near Oliver, B.C. is a classic in this regard. Surface enrichment of uranium here reaches 2000 ppm and although daughter product equilibrium is less than 2%, this still allows the deposit to be detectable by scintillometer. Surface concentrations in alkaline flats are subject to wind erosion.

Not all closed basins produce surface concentrations.  Larger basins have dominantly lateral groundwater flow (rather than vertical), and brine pools may also cause decomplexing of uranyl carbonate at lower levels. Example lb, again from Oliver region, shows a  sediment bottom accumulation in a lake whose sediments are dominantly gypsum, overlain by a purple culture of sulphate-reducing bacteria.

Uranium carbonate complexes entering by groundwaters are either decomplexed by high salinity and sulphate acidity or reduced by the effect of the bacteria on the overall system.  If there are secondary concentrating mechanisms causing uranium deposits to form within the large, saline playas of the Basin and Range province, they have not been observed. Uranium in playa or evaporite environments has been studied by Bell (1955,  1960) and by Leach et al. (1980).

Cyclically flushed

Many saline or alkaline basins are only marginally closed and periodically flushed, the resulting episodes of fresher water leaving organic layers in the clays or marls. The result is typically a layered deposit, although the uranium concentrations do not always correspond to the organic sections. Localization may have more to do with H2S generation, the name "Stink-317 hole" locally applied to Fig. 2 deposit being indicative.  The Starvation Flats deposit (Fig. 3 ) of Stevens County, Washington is an example of a basin which has filled with sediments to the extent that flushing is now quite frequent. As a result, the sediments are dominantly marls in
their lower parts and peats in the upper, and the waters are alkaline but of low salinity. The odour of H2S is again strong in the lower peat layers.

Spring Fed

Although upwelling groundwaters likely play a part in the formation of many young uranium deposits, some are clearly a function of a major spring and are characterized thereby. Where seeps occur below a saline lake or flats, the result will simply be a pod of concentration at that point ( Fig. 4a) unless conditions permit a surface
concentration. The Meyers Flats deposit of Fig. 4b occurs where Victoria Creek passes under porous glacial sediments and resurfaces below a swamp. This rising water appears to oxidize and destroy organics at the underlying sand-peat interface, further concentrating the uranium which reaches as much as 0.3% across half a meter. The upwelling is diffuse, and hence slow. Victoria Creek waters, which run 15-25 ppb uranium, apparently have sufficiently low salinity for adsorption-filtration to be effective at the organic boundary.  In the case of springs involving the initial surfacing of fresh water, radium and sometimes radon may accompany uranium; and radium has a strong tendency to be deposited near spring mouths (Culbert and Leighton, 1981 ). As a result, fresh-water spring deposits may, in part at least, be radioactive. An example from Bennett Lake area of the southern Yukon is shown in Fig. 5, where multiple springs along a major fault system have introduced uranium and radium to the organic accumulations of a sloping meadow.  Although usually quite small, fresh-water spring deposits are relatively widely reported due to their detectability by scintillometer. Examples
are from Colorado (Malan, 1957; Schmidt-Collerus, 1979) and from Wyoming (Love, 1963).

Groundwater intersection

Most young deposits are fed to a major extent by groundwater, but this class is represented by sites where moving groundwater has simply been intersected by a dip in topography with resulting lake or marsh and organic growth. One feature of such deposits is their assymetry, being richer on the inflow side, and with uranium elsewhere concentrated mainly along the interface of the organic materials with the underlying silt or sand. Deposits are also controlled by basal topography of the trap. Figure 6a shows an unusual case in which there is bottom leakage from a sink in the down-flow side, leaving a well-defined uranium concentration in the upflow basin and a profile without clear concentrations in the deeper sink. The alkaline water example (Fig. 6b) is a more simple and typical case.  Groundwater intersection deposits forming from fresh water tend to be small, as sufficient water flowage for larger accumulations would require surface drainage.

Collection basin

One of the most common sites of deposit formation is the collection basin, often near a valley head or valley junction, where both ground and surface waters are collected in a marshy bowl or lake with surface runoff. This runoff precludes development of saline waters, but sizeable deposits accumulate from both fresh and alkaline systems in this fashion. One such bowl is the Prairie Creek meadows in the town of Summerland, B.C. (Fig. 7). This "meadow" was once a marsh, but has been drained for agriculture and residential construction.  Morphologically, collection basin deposits tend to have complex drainage. Where the drainage is diffuse and its sources of variable uranium content, the uranium distribution will tend to be quite complex in plan view, as in Fig. 7. Where drainage is well-defined and of more homogeneous composition, uranium per unit area tends to depend more on the depth of organic profile and may be more regularly distributed, as in the fresh-water Whooper Swamp deposit of New Brunswick ( Fig. 8).

Valley swamp or lake

This style of deposit forms by partial damming or glacial excavation of a valley, and is one of the most frequent. Some occur in what seem to be little more than historically common sites for beaver dams. They vary from the next class in a lack of a well-defined drainage channel, causing a more diffuse passage of water through the sediments and leaving fewer sand or gravel layers.  The deposits vary widely in shape, although there is usually a concentration of uranium at the upstream end. In some cases, both near surface and near-base concentrations form behind this as the result of the free passage of waters on the surface and in underlying sands, resulting in an arcuate or "roll" shape of uranium accumulation. More commonly, concentrations are determined by interaction with groundwaters and with side drainages, such as in the Ruby No. 2 deposit of Pend Orielle County, Washington (Fig. 9b).  Where the water is sufficiently shallow for widespread growth of sphagnum or reeds, a layer of uranium may form near the level of decomposition of plant fragments. This may be due to the resulting reducing environment, or to the incipient production of humic and fulvic acids.  The effect is apparent in the case of Fig. 9a, showing a swamp bordering the Westbench suburb of Penticton, B.C.
Snip


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http://aris.empr.gov.bc.ca/ArisReports/28174.PDF might be of interest if you consider these keywords

uranium ores, bogs, springs, peat, ash content, heavy metals, uranium, mineral exploration british columbia

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more keywords based on    young uranium post-glacial    you might eventually end up here




And Here

The formation of basal-type uranium deposits in south central British Columbia    Dan R. Boyle

 look for    Blizzard

 


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