diff --git a/scientific/seismology/miniseed3.ksy b/scientific/seismology/miniseed3.ksy
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+meta:
+  id: miniseed3
+  title: "MiniSEED 3 Data Format"
+  file-extension: 
+    - mseed3 
+    - mseed
+  license: MIT
+  encoding: ascii
+  endian: le
+doc: |
+  MiniSEED 3 is a binary data format defined by the International Federation of Digital 
+  Seismograph Networks (FDSN) for data collection, archiving and exchange of seismological data. 
+doc-ref: https://docs.fdsn.org/projects/miniseed3
+seq:
+  - id: data_record
+    type: data_record
+    repeat: eos
+types:
+  data_record: 
+    doc-ref: https://docs.fdsn.org/projects/miniseed3/en/latest/definition.html#description-of-record-fields
+    seq: 
+      - id: record_header_indicator
+        contents: "MS"
+      - id: format_version
+        type: u1
+      - id: flags
+        type: miniseed_flags 
+      - id: record_start_time
+        type: miniseed_time
+      - id: data_payload_encoding
+        type: u1
+        enum: miniseed_data_encoding
+      - id: sample_rate_or_period
+        type: f8
+      - id: number_of_samples
+        type: u4
+      - id: crc_of_the_record
+        type: u4
+      - id: data_publication_version
+        type: u1
+      - id: length_of_identifier
+        type: u1
+      - id: length_of_extra_headers
+        type: u2
+      - id: length_of_data_payload
+        type: u4
+      - id: source_identifier
+        type: str
+        size: length_of_identifier
+        encoding: ASCII
+      - id: extra_header_fields
+        type: str
+        size: length_of_extra_headers
+        encoding: ASCII
+      - id: data_payload
+        type: 
+          switch-on: data_payload_encoding
+          cases: 
+            'miniseed_data_encoding::encoding_text': miniseed_data_encoding_text 
+            'miniseed_data_encoding::encoding_16_bit_integer': miniseed_data_encoding_16_bit_integer
+            'miniseed_data_encoding::encoding_32_bit_integer': miniseed_data_encoding_32_bit_integer
+            'miniseed_data_encoding::encoding_32_bit_float': miniseed_data_encoding_32_bit_float
+            'miniseed_data_encoding::encoding_64_bit_float': miniseed_data_encoding_64_bit_float
+            'miniseed_data_encoding::encoding_steim_1': miniseed_data_encoding_unknown # Not yet supported
+            'miniseed_data_encoding::encoding_steim_2': miniseed_data_encoding_unknown # Not yet supported
+            'miniseed_data_encoding::encoding_steim_3': miniseed_data_encoding_unknown # Not yet supported
+            'miniseed_data_encoding::encoding_opaque_data': miniseed_data_encoding_unknown 
+  miniseed_flags:
+    seq:
+      - id: calibration_signals_present
+        type: b1
+      - id: time_tag_is_questionable
+        type: b1
+      - id: clock_locked
+        type: b1
+      - id: reserved_flag_3
+        type: b1
+      - id: reserved_flag_4
+        type: b1
+      - id: reserved_flag_5
+        type: b1
+      - id: reserved_flag_6
+        type: b1
+      - id: reserved_flag_7
+        type: b1 
+  miniseed_time:
+    seq:
+      - id: nanosecond
+        type: u4
+      - id: year
+        type: u2
+      - id: day_of_year
+        type: u2
+      - id: hour
+        type: u1
+      - id: minute
+        type: u1
+      - id: second
+        type: u1
+  miniseed_data_encoding_unknown: 
+    seq:
+      - id: data
+        type: u1
+        repeat: expr
+        repeat-expr: _parent.length_of_data_payload
+  miniseed_data_encoding_text: 
+    seq:
+      - id: data
+        type: str
+        size: _parent.length_of_data_payload
+        encoding: UTF-8
+  miniseed_data_encoding_16_bit_integer:
+    seq:
+      - id: data
+        type: s2
+        repeat: expr
+        repeat-expr: _parent.number_of_samples
+  miniseed_data_encoding_32_bit_integer:
+    seq:
+      - id: data
+        type: s4
+        repeat: expr
+        repeat-expr: _parent.number_of_samples
+  miniseed_data_encoding_32_bit_float:
+    seq:
+      - id: data
+        type: f4
+        repeat: expr
+        repeat-expr: _parent.number_of_samples
+  miniseed_data_encoding_64_bit_float:
+    seq:
+      - id: data
+        type: f8
+        repeat: expr
+        repeat-expr: _parent.number_of_samples
+enums:
+  miniseed_data_encoding:
+    0: encoding_text
+    1: encoding_16_bit_integer
+    3: encoding_32_bit_integer
+    4: encoding_32_bit_float
+    5: encoding_64_bit_float
+    10: encoding_steim_1
+    11: encoding_steim_2
+    19: encoding_steim_3
+    100: encoding_opaque_data