Aquifers, Faults, Subsidence, and Lightning Databases

Transcription

1 Aquifers, Faults, Subsidence, and Lightning Databases K. S. Haggar, L. Denham, H.R. Nelson, Jr. Dynamic Measurement, LLC NOGS 1

2 OUTLINE 1. Introduction and Theory 2. Geologic Setting in Texas Study Area 3. Aquifers / Earth Tides / Geothermal Gradient 4. Conclusions NOGS 2

3 Lightning Theories and Facts Lightning occurs everywhere. Cloud to cloud lightning travels up to about 150 miles (250 km). Cloud to ground lightning follows terralevis/shallow earth currents which reflect geology. Some strikes do hit topography, vegetation, and infrastructure, but can be edited out from location and attribute data. Lightning Attributes contain data from various depths and image subsurface features and lineaments such as transforms, faults, drainage basins, and paleo channels. NOGS 3

4 Main lightning bolt tied to geology Copyright 2014 NOGS 4

5 350 million annual Lightning Strikes - a rich database to mine Lightning Strikes can travel 250 km (155 miles) cloud-to-cloud, or 2 ½ times the distance of Sprites or Elves. Lightning Strike locations primarily controlled by terralevis (shallow earth) currents. Copyright 2014 NOGS 5

6 330 Sensors record U.S. lightning strike locations with feet ( meter) horizontal resolution Copyright 2014 NOGS 6

7 Vaisala Partnership Exclusive worldwide license with Vaisala of Finland to use their data in the NLDN and GLD- 360 for natural resource exploration. Copyright 2014 NOGS 7

8 Strike Density (NLDN) and Topography Lightning density regionally controlled by meteorology, and locally controlled by terralevis (shallow earth) currents. 04 May 2015 NOGS 10

9 Proven and Patented Technology Copyright 2014 NOGS 9

10 Lightning Two conducting plates, the storm cloud and the earth, are separated by an insulating dielectric, the atmosphere. Voltage is created by collision of ice within the cloud and lightning bolts rebalance the charge between the plates. Base of charged cloud Capacitor Lightning Sparks from ice collisions R between plates R of atmosphere as a dielectric Earth Surface NOGS 10

11 Lightning Measurements/Attributes, & Wave Form Location / Time and Duration / # of Sensors Rise Time Peak Current Peak to Zero Polarity Chi Squared Number of Sensors NOGS 11

12 Location Time and Duration Lightning Strike Measurements Rise Time Peak Current Polarity Peak-to-Zero Density Copyright 2014 NOGS 12

13 2. Geologic Setting in Texas Study Area Aquifers / Faults / Stratigraphy / Subsidence Rise-Time Central Texas NOGS 13

14 Fault Trends and Geothermal Gradient Washington Montgomery Liberty Fayette Harris Chambers Lavaca Colorado Wharton Fort Bend Matagorda Jackson Calhoun Study Area Fault trends by Ewing 1990 Geothermal Gradient Map NOGS 14

15 Aquifers Brazos River Alluvium Aquifer Trinity - Edwards Carrizo - Wilcox Gulf Coast Aquifers from Texas Water Development Board Report 380. NOGS 15

16 Houston Galveston Area Subsidence in Gulf Coast Aquifer From Houston Galveston Subsidence District with permission NOGS 16

17 Topography Rise-Time Well Data, Faults, and 3-D Seismic Green Dots are Well Locations NOGS 17

18 Negative Peak Current Peak-to-Zero Regional Scale Colorado County, Texas NOGS 18

19 Rise-Time Peak Current Prospect Scale Colorado County, Texas NOGS 19

20 Peak Current Peak-to-Zero Prospect Scale Colorado County, Texas NOGS 20

21 3. Applied Lightning Data in Texas Study Area Earth Tides / Geothermal Gradient Peak-to-Zero Central Texas NOGS 21

22 Brazos Aquifer Absolute Peak-Current NOGS 22

23 Rate of Change of Lunar/Solar Tides North Texas Example (Normalized Over Lunar Cycle) Florida Example Green = Red/Gray Red = Lightning Strike Frequency Outgoing Tide Incoming Tide Incoming Tide Possibly Washes Out Biogenic Gas If Tidal Gradient had no effect All Green Values = 1.0 NOGS 23

24 Tidal Gradient when Strikes Occur Outgoing Tide Incoming Tide Raccoon Bend Hockley Tide Gradient Frequency Sealy Tide Gradient Lightning Frequency NOGS 24

25 Strike Density at High Tidal Gradient Tide Gradient Normalized Lightning Frequency Tide Gradient Combined Frequency NOGS 25

26 Strike Density Wells <1,500 m (4,920 Feet) Vs. Geothermal Gradient For shallow depth lightning strike density is largely independent of temperature gradient. NOGS 26

27 Strike Density for Wells m ( feet) Vs. Geothermal Gradient Lightning strike density decreases with increasing temperature gradient. NOGS 27

28 Strike Density for Wells >3000 m (>9,843 Feet) Vs. Geothermal Gradient Lightning strike density decreases more rapidly with increasing temperature gradient. NOGS 28

29 Lightning Strike Density for All Wells Vs. Geothermal Gradient Negative Correlation Coefficient Increases with Depth, while the Geothermal Gradient also is Lower for Deeper Measurements. NOGS 29

30 Conclusions and Lagniappe Lightning is a new geophysical data type. Strike locations and attributes primarily controlled by earth currents and geology. Lightning strikes highlight geological features and sediment/rock characteristics. Integration of lightning data provides a better understanding of the subsurface. NOGS 30

31 Thanks You for your Time! Slides on-line at Keep up with new developments at: AAPG, 1-3 June 2015, Denver LIFE, August 2015, Houston GCAGS, September 2015, Houston SEG, October 2015, New Orleans NOGS 31

32 Goose Point ResistivityVolume NOGS 32 55

33 Goose Point Permittivity Volume NOGS 33 56

34 NOGS 34

35 Goose Point Interpretation NOGS 35 54

36 Approximate Integration with interpretation Shelly Roth - UNO MS Thesis 1999 (top right ) NOGS 53

37 NOGS 37

38 Conventional 2-D and 3-D Resistivity Images over Willow Creek Fault in Tomball, TX NOGS 38

39 Willow Creek Resistivity Volume NOGS 39

40 Willow Creek Permittivity Volume NOGS 40

41 Hockleyn Resistivity Expanded 5C, 6A, 7B Area 2 10-Jul-15 All Rights Reserved. NOGS41

42 Geological Significance of Lightning Attributes 2/6 NOGS 42

43 Geological Significance of Lightning Attributes 3/6 NOGS 43

44 Geological Significance of Lightning Attributes 4/6 NOGS 44

45 Geological Significance of Lightning Attributes 5/6 NOGS 45

46 Geological Significance of Lightning Attributes 6/6 NOGS 46

47 Geological Significance of Lightning Attributes NOGS 47