Laserfiche WebLink
<br />TABLE OF CONTENTS <br />Paae <br />1.0 SUMMARY OF MAJOR FINDINGS ................................................................................1 <br />2.0 OVERVIEW OF FIELD GEOLOGIC STUDIES DURING JULY 12 -16, 2004 ................3 <br />3.0 INTRODUCTION .............................................................................................................4 <br />4.0 MINING METHOD ...........................................................................................................5 <br />5.0 GEOLOGIC FACTORS INFLUENCING SUBSIDENCE ..................................................6 <br />6.0 FIELD RECOGNITION OF SUBSIDENCE AND NON-SUBSIDENCE FEATURES IN <br />THE WEST ELK MINE AREA .........................................................................................7 <br />6.1 Subsidence Cracks and Compression Features..........--° ....................................°-..°-------- 7 <br />6.2 L7esiccationCradcs..--°-°-.....--° ......................°-°-.....--°-°-................--°-...................--°°°-8 <br />6.3 Pseudo Subsidence Cracks (Gravely-Induced Tension Cracks) .........................................8 <br />• 7.0 SUBSIDENCE PREDICTION BASED ON PAST LONGWALL MINING .......................10 <br />7.1 Vertical and Hor¢ontal Displacement, Tell, Curvature, and Hor¢ontal Strain ...................10 <br />7.1.1 Ma~dmum Vertical Displacement (Subsidence) .................................................13 <br />7.1.2 Ma~dmum Tilt.°-...........°--°............°°° ................... °..........----.........................14 <br />7.1.3 Ma~dmum Hor¢ontal Strain .........................................................................•--...14 <br />7.2 Ma~dmum Projected Depths of Surface Cracks ..................°°°---°-°-•-°--.....--•--..°-..........15 <br />8.0 FIELD OBSERVATIONS AND EVALUATIONS AT INDMDUAL LOCATIONS FROM <br />JULY 12 THROUGH JULY 16 ......................................................................................17 <br />8.1 Location 1 .................................................................°°-....................-°-°-.........................19 <br />8.2 Location 2 ............................................................................................°-.................-°-°....20 <br />8.3 Logtion 3--°°° .............................•••-..............................--°............................--°-.....°--.....21 <br />8.4 Location 4 ..........................................................°--.....-°-°.................--°-...-°-....................23 <br />8.5 Location 5 ..........................................°--°...............°°°.......................-°--..................-°--..25 <br /> <br />9.0 CONCLUSIONS ............................................................................................................27 <br /> <br />