Virgin River DCIP Report

Transcription

1 Virgin River 1 1 University of British Columbia Geophysical Facility Applied Geophysics, 2010

2 Outline 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

3 Outline Location Survey Specs 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

4 Regional Athabasca Basin, Northern Saskatchewan Location Survey Specs Northern Saskatchewan South Central Athabasca Basin NTS Reference 74 G/12

5 Location Survey Specs Local Wide Lake Grid 10 Lines running NW-SE Approximately 4km long each Approximately 40 line-km total

6 Outline Location Survey Specs 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

7 Electrode Conguration Pole-Pole Location Survey Specs Collected in Summer by Patterson Geophysics Ltd. Pole Spacing a = 150m 12 Stainless Steel Electrodes (Including Innites)

8 Electrode Conguration Current Advance Protocol Location Survey Specs For Electrodes n=1:6 Advance in Increments of 75m For Electrodes n=7:10 Advance in Increments of 150m Data Collected at Current-Potential Electrode Spacings of... 75m, 150m, 225m, 300m, 375m, 450m, 525m, 600m, 675m, 750m, 825m, 900m, 1050m, 1200m, 1350m, and 1500m.

9 Hardware Instrument Specications Location Survey Specs Walcer TX kw IP Transmitter Walcer MG-12 Motor Generator Two IRIS Instruments ELREC Pro Time Domain IP-Resistivity Receivers

10 Data Files Provided to UBC-GIF Location Survey Specs RES2DINV File (.dat) Reduced data format for RES2DINV software Excel Spreadsheet (.xls) File containing most of the raw data: Voltage (mv) Current (A) Self Potential (mv/v) 20 Chargeability Channels (mv/v) Local Tx/Rx Electrode Coordinates Reduced Excel Spreadsheet (.xls) Reduced data format for plotting pseudo-sections from Excel

11 Data Quality Location Survey Specs Duplicates Data are mostly duplicated Typically very similar IP Data Very noisy Not very useful

12 Outline 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

13 Errors Noise oor + 5% of each Datum 2D: Noise oor calculated as 90% of smallest value along line 3D: Noise oor calculated as 90% of smallest value

14 Outline 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

15 Survey Lines

16 Local Grid: Default Parameters Data

17 Local Grid: Default Parameters Results

18 Local Grid: Default Parameters Results

19 UTM: Fine Mesh Data

20 UTM: Fine Mesh Results

21 Outline 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

22 UTM: Default Parameters Parameters Data 3582 Mesh cells Core Cell Size 75m 75m 37.5m Reference Model 1000Ωm Mist 4059

23 UTM: Default Parameters Vertical Slice through Line 1200N

24 UTM: Default Parameters Surface View

25 UTM: Default Parameters 375m Depth Slice

26 UTM: Default Parameters 750m Depth Slice

27 UTM: Default Parameters Resistivity Cuto of 300Ωm

28 Problems Topics worth Revisiting Duplicated Data IP Chargeability Noisy Surface

29 Duplicated Data Comparison at 600m Depth Slice

30 IP Chargeability Decay Curves

31 IP Chargeability Datum 554 Mesh cells Core Cell Size 75m 75m 37.5m Mist 2539

32 IP Chargeability 600m Depth Slice: Useful...?

33 Surface Weighting Surface View

34 Surface Weighting Vertical Slice through Line 1200N

35 Surface Weighting 375m Depth Slice

36 Surface Weighting 750m Depth Slice

37 Outline Correlations Snowbird Tectonic Zone 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

38 ZTEM Recall From Elliott's Presentation... Correlations Snowbird Tectonic Zone

39 Outline Correlations Snowbird Tectonic Zone 1 Location Survey Specications 2 3 Correlations Snowbird Tectonic Zone

40 Snowbird Tectonic Zone Graphitic Fault Oset Correlations Snowbird Tectonic Zone

41 Snowbird Tectonic Zone Graphitic Fault Oset Correlations Snowbird Tectonic Zone

42 Feedback, Questions & Opinions What Do You Think?