Harper has mapped the Carswell structure as comprising an uplifted basement core of Archean and/or Aphebian high-grade metamorphic rocks surrounded by inner and outer rings of deformed but unmetamorphosed Athabasca Group sediments. The crater-like morphology of the structure, the presence of polymict breccias of volcanic aspect (Cluff Breccia) and the occurrence of shock metamorphic features such as deformation lamellae in quartz, shatter cones in the metamorphic rocks, pseudotachylite, and shattered cobbles and boulders in basal conglomerates of the William River Subgroup lead Harper to believe that the structure was formed by meteorite impact.
     The area of the showing was mapped by Harper as lying within a unit of quartzofeldspathic gneisses bounded to the southeast by pegmatites and to the northeast by granodioritic rocks.
     The showing itself consists of a small garnetite block located at the surface which assayed 0.760% U3O8. A trench dug in the vicinity exposed radioactive Cluff Breccia veins in fractured mylonitized bedrock. Detailed geochemical sampling outlined an anomaly returning 195 ppm U in the area.

     The area was under exploration for economic uranium deposits as early as 1958 when Lundberg Exploration Ltd. flew magnetic and radiometric surveys over the entire Carswell Dome area which covered NTS areas 74K-05, -06, -11 and -12 for W.S. Kennedy (1958) Grubstake. Two topographic features consisting of a circular pattern and a southwest-striking lineament were tested with the survey and three magnetic anomalies were located: one north of Carswell Lake, a second two miles (3.2 km) east of the central part of Carswell Lake and a third consisting of a zones circular pattern centred 3 miles (4.8 km) south of Carswell Lake. Noted radiometric anomalies corresponded to the circular structural pattern.
     Mokta Ltd. (Amok) flew a gammametric survey over the structure in 1967 to 1968. The claim block 2327 was registered 2 August 1968.
     Exploration in 1969 consisted of helicopter-borne outcrop reconnaissance and corresponding ground scintillometer prospecting and mapping. No anomalies were outlined.
     Another magnetic survey was flown for Amok in 1970 which enabled the Carswell Dome area to be subdivided into three distinct lithological units: a unit of granite intrusion and intense granitization, a unit of granite gneiss and a unit of amphibolite gneiss. A radiometric survey was also completed and several anomalies were outlined and subsequently followed up by geological surveys.  The anomalies were attributed to boulders of pegmatitic, granitic or feldspathic composition in basal moraine, folded outcrops of gneiss or granite, or radioactive swamps.
     Ten conductive zones were outlined by an airborne EM-input survey completed by Questor Surveys Ltd. in 1971 and a geochemical survey of drainage channels located no anomalies. Work in the Sophie area, north of Bridle Lake, consisted of geological and radiometric prospecting. Only feldspathic outcrops were noted. Two magnetic anomalies were located in an area of previously noted magnetic anomalies. Work east of Bridle Lake, in what has become known as the Laure Area, consisted of geological and radiometric prospecting, detailed geochemical sampling, a resistivity survey, radon survey and trenching. Five anomalies were outlined as a result of the prospecting. The radon survey exposed an anomaly near the second radiometric anomaly, and subsequent trenching exposed yellow products in small cracks in feldspathic bedrock.
     Geochemical surveys completed in 1972 outlined anomalies which were usually attributed to swamps and topographic depressions. A program of diamond drilling, grid cutting, scintillometer grid surveying and geological surveying was begun and completed in the following year.
     An airborne spectrometer survey, completed over the entire area in 1973, was followed up by geological surveys in the Sophie-Laure areas.  Bedrock of pegmatoid, granite, quartzofeldspathic rocks and paragneiss outcrops were located and two outcrops of ferrous paragneiss with magnetite-rich quartzo-feldspathic beds were located in the Laure Area.
     The next year strategic geochemical sampling was completed over the entire Dome area as well as VLF-EM surveys. In the showing area geological mapping, detailed radiometric prospecting and detailed geochemical sampling were completed. The noted airborne anomalies were observed to be due to pegmatoid and/or gneissic boulders in moraine. Prospecting outlined several uraniferous anomalies and analysis returned values as high as 0.76% U3O8. These new anomalies comprised mostly angular pegmatoid boulders, although some outcrops containing yellow uranium products within fractures were noted. It was as a result of this sampling that the showing was identified, as well as SMDI 1154, 1156, 1157 and 1158.  Diamond drilling was begun this year.
     Detailed geochemical surveys in the Sophie-Laure area in 1975 returned high U values which were usually accompanied by high Pb values. Percussion drilling was completed as well.
     Further exploration in 1976 consisted of trenching, overburden drilling and sampling, and another radon survey.  The sampling program resulted in several uranium-poor, lead-rich samples being located.  More geology, geophysics and geochemistry were reported (AF 74K05-0074).
     No further work was reported for the area until 1979, when a high sensitivity aeromagnetic survey was completed over the area. Diamond drilling, percussion drilling, mapping and prospecting were also completed over the area. By this time the claim block had converted to ML 5249. Nothing pertaining to the showing was noted.
     In 1980, Amok completed diamond drilling, percussion drilling, geological mapping, radiometric prospecting, VLF-radiohm, radon, ground magnetic and maxi-probe-EMR 16 surveys, and in 1981 diamond drilling, detailed surveying, prospecting, mapping and trench mapping was completed.
     Overburden drilling and sampling, detailed surveying, organic sampling, prospecting, mapping, trench mapping and geophysical surveys were completed the next year, as well as a helicopter-borne EM survey. In 1984, more overburden sampling and trenching was completed and in 1985 a work summary was submitted.              
     In 1994, Cogema Resources flew a GEOTEM survey which covered the showing (AF 74K-0012).

74K-0008;-0012, 74K05-0001;-0007;-0022;-0032;-0040;-0041;-0042; 74K05-0046;-0055;-0065;-0093;-0092;-0110;-0111;-0112;-0113;-0114 74K05-0113;-0114;-0126;-0127,

Dunn, C.E. (1980): Lake Sediment and Water Geochemistry of the Carswell Structure: Sask. Geol. Surv. Rep. No. 224; 36p. Harper, C.T. (1982): Geology of the Carswell Structure, Central Part (Parts of NTS Areas 74K-5, -6, -11, -12); Sask. Miner. Resour.; Rep. 214, 6p.

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