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+Trace Metadata
+--------------
+
+Metadata is stored in the `Stats` dictionary of each `Trace` object.
+
+- `network`
+  Network code.
+
+  Always `NT`
+
+- `station`
+  Observatory code.
+
+  Examples:
+    `BOU`
+    `BDT`
+
+- `channel`
+  Data channel.
+  
+  Examples:
+    `H`
+    'D'
+    'Z'
+    'F'
+
+- `agency_name`
+  Name of agency that operates observatory.
+
+- `station_name`
+  Name of observatory.
+
+- `geodetic_latitude`
+  Latitude of observatory in decimal degrees [-90, 90].
+
+- `geodetic_longitude`
+  Longitude of observatory in decimal degrees [0, 360].
+
+- `elevation`
+  Elevation of observatory in meters.
+
+- `sensor_orientation`
+  Array of channels recorded by sensor.
+
+- `sensor_sampling_rate`
+  How frequently sensor sampled in hertz.
+
+- `data_type`
+  Review level of data.
+
+  Examples:
+    `definitive`
+    `provisional`
+    `quasi-definitive`
+    `variation`
+
+- `data_interval`
+  Time between data samples.
+
+  Examples:
+    `daily`
+    `hourly`
+    `minute`
+    `monthly`
+    `second`
+
+- `data_interval_type`
+  How data interval was produced.
+
+  Examples:
+    `average 1 second`
+    `filtered 1-minute (00:15-01:45)`
+
+- `declination_base`
+  Observatory declination baseline.
+
+- `is_intermagnet`
+  Whether data is available via intermagnet.
+
+- `conditions_of_use`
+  Disclaimer for usage.
+
+- `filter_comments`
+  Comments about how data was filtered.
+
+- `comments`
+  Other comments about this data.
+