This dataset contains U-Pb geochronology analyses of detrital zircon from Lower Jurassic to Lower Cretaceous strata of the southern Canadian Rocky Mountains fold-and-thrust belt, collected between approximately 49° 30’N and 53° 30’N. The sample suite includes 17 samples from all coarser clastic units of the Fernie Formation, 8 samples from the first massive (commonly >1m thick) sandstone bed assigned to the basal Morrissey and Nikanassin formations and 4 samples from the Cadomin Formation. The samples were submitted to the Canadian Centre for Isotopic Microanalysis (CCIM) of the University of Alberta where approximately 120 individual zircon grains were analyzed from each sample using laser ablation multi collector inductively coupled mass spectrometry, for a total of 3213 single zircon ages.

For interpretation purposes the data were culled using a 10% discordance filter with the following criteria: for ages greater than 500 Ma, concordance was assessed by comparing the 206Pb/238U and 207Pb/206Pb ages, for ages less than 500 Ma, concordance was assessed by comparing the 207Pb/235U and 206Pb/238U ages. Approximately 20% of the analyses with >10% discordance values were rejected, leaving 2499 age values that were used for interpretation.

The dataset consists of three individual files:

Geochronology Data - contains all the isotope and age data results;

Standard - contains the results of the sample standards analyses, and

Percent Rejected - shows the percentage of grains from each sample that were rejected using the 10% discordance filter.

The data were filtered using a 10% discordance filter with the following criteria: for ages greater than 500 Ma, concordance was assessed by comparing the 206Pb/238U and 207Pb/206Pb ages, for ages less than 500 Ma, concordance was assessed by comparing the 207Pb/235U and 206Pb/238U ages.

Analytical errors for each ratio are captured in the table as two standard deviations in the 2 sigma columns.

The data are as reported by the CCIM.