GIS & Geospatial Technology Flashcards

Which GIS operation would a land department use to combine multiple adjacent lease polygons held by the same operator into a single unified polygon for unitization mapping?

Answer: Dissolve

The Dissolve operation merges adjacent or overlapping polygons that share a common attribute value (such as operator name) into a single unified polygon, ideal for creating unitization maps.

In GIS-based lease management, what is the purpose of a 'spatial index' on a feature class?

Answer: To speed up spatial queries and rendering by organizing features by geographic location

A spatial index pre-organizes feature geometry so the GIS engine can quickly locate features in a geographic area without scanning the entire dataset, dramatically speeding up queries on large lease databases.

A landman is reviewing a GIS map that shows a well located outside its permitted lease boundary. Which GIS analysis most directly identifies the amount of encroachment?

Answer: Point-in-polygon spatial query combined with distance measurement

A point-in-polygon query confirms the well lies outside the lease boundary, and a distance measurement then quantifies exactly how far the wellbore has encroached beyond the permitted lease limit.

What is the function of the 'clip' geoprocessing tool in oil and gas GIS work?

Answer: Cutting a feature class to the extent of a defined boundary polygon, keeping only features inside

The Clip tool trims an input feature class to the shape of a clip boundary polygon, retaining only the portions of features that fall within the boundary—useful for extracting leases within a specific study area.

Which of the following best describes 'LiDAR' data and a practical application for oil and gas landmen?

Answer: Light Detection and Ranging — high-resolution elevation data used for precise terrain modeling and pipeline route planning

LiDAR uses laser pulses to capture highly accurate elevation data, enabling detailed terrain modeling that supports pipeline routing, site selection, and surface damage assessment relevant to land negotiations.

When a GIS feature class stores oil and gas well data, which attribute field is most critical for linking to state regulatory agency databases?

Answer: The API (American Petroleum Institute) well number

The API well number is the standardized 10-digit identifier assigned by state regulatory agencies and used universally to link GIS well features to completion reports, production data, and regulatory records.

A company's GIS land layer shows a lease polygon that does not align with the county assessor's parcel boundaries. What is the most likely cause and appropriate corrective action?

Answer: The datasets use different coordinate systems or datums requiring a projection transformation or datum shift

Misalignment between datasets typically results from different coordinate systems or datums; applying the correct projection transformation or datum shift brings the layers into accurate spatial registration.