Landsat 5
imagery was used to analyze the Ventura County study area in August of 1997,
2009, and 2011. The year 1997 was used as a “baseline” for vegetation in this
study, as it is primarily concerned with recent drilling since 2011. Imagery
from August were used to avoid cloud contamination in the imagery and to
provide a standard for summer vegetation. Images from 2009 were used to provide
a visualization of vegetation change before the recent increase in drilling.
Using the USGS Global Visualization Viewer (GLOVIS), LandSat 5 imagery of Ventura County (path 41, row 36) was downloaded. Imagery was then modified and analyzed using ENVI remote sensing software to create Normalized Difference Vegetation Indices (NDVI), thermal imagery, and change detections.
The Normalized Difference Vegetation Index (NDVI) is a graphical indication of vegetation density from -1 (water) to 1 (temperate and tropical rainforests). This NDVI was made using the visible red (band 3, .63-.69 µm) and near infrared (band 4, .76-.90 µm) bands on the Landsat 5’s Thematic Mapper (TM) sensor. A value of zero represents a neutral area consisting of rock, sand or snow. This NDVI is mapped out on a graduated color scale between a series of hues representing the index. The study’s analysis uses a blue to white NDVI scale, where negative values are represented by darker hues and therefore less vegetation, while light hues represent high indices and high vegetation.
Thermal images were gathered by analyzing TM’s band 6. These images were modified using ENVI in an orange to white gradient, with white representing highest temperatures. Change detections were done on both the NDVIs and thermal imagery to show changes in vegetation and temperature correlated with drilling. Analysis in ArcGIS was also done to illustrate the geographic locations of each hydraulically fractured well in the study area. Data was provided by the California Department of Conservation. Through the implantation of attribute queries, we selected hydraulically fractured wells of our target locations. This analysis was exported into raster form and placed back into ENVI.
Using the USGS Global Visualization Viewer (GLOVIS), LandSat 5 imagery of Ventura County (path 41, row 36) was downloaded. Imagery was then modified and analyzed using ENVI remote sensing software to create Normalized Difference Vegetation Indices (NDVI), thermal imagery, and change detections.
The Normalized Difference Vegetation Index (NDVI) is a graphical indication of vegetation density from -1 (water) to 1 (temperate and tropical rainforests). This NDVI was made using the visible red (band 3, .63-.69 µm) and near infrared (band 4, .76-.90 µm) bands on the Landsat 5’s Thematic Mapper (TM) sensor. A value of zero represents a neutral area consisting of rock, sand or snow. This NDVI is mapped out on a graduated color scale between a series of hues representing the index. The study’s analysis uses a blue to white NDVI scale, where negative values are represented by darker hues and therefore less vegetation, while light hues represent high indices and high vegetation.
Thermal images were gathered by analyzing TM’s band 6. These images were modified using ENVI in an orange to white gradient, with white representing highest temperatures. Change detections were done on both the NDVIs and thermal imagery to show changes in vegetation and temperature correlated with drilling. Analysis in ArcGIS was also done to illustrate the geographic locations of each hydraulically fractured well in the study area. Data was provided by the California Department of Conservation. Through the implantation of attribute queries, we selected hydraulically fractured wells of our target locations. This analysis was exported into raster form and placed back into ENVI.
Hi, I'm very interested in your study, please contact me.
ReplyDeleteVCinfocus@gmail.com
www.vcinfocus.com
cell: 805-727-1393
Thanks, Kimberly Rivers
Freelance Reporter in Ventura County
Compared with accepted techniques using full-scale rigs and benchmark drill pipe, Coiled-Tubing Drilling (CTD) can significantly decrease environmental influence. CTD is mostly a reentry drilling service that enables operators to more competently find hydrocarbon pouches still untapped in the reservoir. Reentry wells reduce the locality at the exterior impacted by drilling, but also reduce the volumes of iron alloy, cement, and drill cuttings conceived in the drilling method with Hydraulic Fracturing Process. Coiled-tubing technologies replace the customary rigid, jointed drill pipe with a long, flexible coiled pipe string. This can reduce the cost of drilling, as well as supply a smaller environmental footprint. In particular, less drilling grime is needed, which decreases the use of nonrenewable assets and minimizes the promise for unplanned issues. Coiled tubing furthermore uses slimhole drilling techniques to accomplish very cost-effective drilling and less impact on the natural environment. In supplement, because drilling procedures are not cut off for pipe connections and with Well Fracturing, CTD can use shut" mud circulation methods, which decrease the risk of spills and blowouts.
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