diff --git a/contrib/seekable_format/zstd_seekable_compression_format.md b/contrib/seekable_format/zstd_seekable_compression_format.md
index 55aebfd2e9d..5b87c7f7016 100644
--- a/contrib/seekable_format/zstd_seekable_compression_format.md
+++ b/contrib/seekable_format/zstd_seekable_compression_format.md
@@ -14,7 +14,7 @@ are clearly marked.
 Distribution of this document is unlimited.
 
 ### Version
-0.1.0 (11/04/17)
+0.2.0 (31/07/21)
 
 ## Introduction
 This document defines a format for compressed data to be stored so that subranges of the data can be efficiently decompressed without requiring the entire document to be decompressed.
@@ -78,26 +78,31 @@ A bitfield describing the format of the seek table.
 
 | Bit number | Field name                |
 | ---------- | ----------                |
-| 7          | `Checksum_Flag`           |
-| 6-2        | `Reserved_Bits`           |
+| 7          | `XXH64_Checksum_Flag`     |
+| 6          | `SHA512-256_Checksum_Flag`|
+| 5-2        | `Reserved_Bits`           |
 | 1-0        | `Unused_Bits`             |
 
-While only `Checksum_Flag` currently exists, there are 7 other bits in this field that can be used for future changes to the format,
+While only `Checksum_Flag` currently exists, there are 6 other bits in this field that can be used for future changes to the format,
 for example the addition of inline dictionaries.
 
-__`Checksum_Flag`__
+__`XXH64_Checksum_Flag`__
 
 If the checksum flag is set, each of the seek table entries contains a 4 byte checksum of the uncompressed data contained in its frame.
 
+__`SHA512-256_Checksum_Flag`__
+
+If the checksum flag is set, each of the seek table entries contains a 32 byte SHA-512/256 checksum of the uncompressed data contained in its frame.
+
 `Reserved_Bits` are not currently used but may be used in the future for breaking changes, so a compliant decoder should ensure they are set to 0.  `Unused_Bits` may be used in the future for non-breaking changes, so a compliant decoder should not interpret these bits.
 
 #### __`Seek_Table_Entries`__
 
 `Seek_Table_Entries` consists of `Number_Of_Frames` (one for each frame in the data, not including the seek table frame) entries of the following form, in sequence:
 
-|`Compressed_Size`|`Decompressed_Size`|`[Checksum]`|
-|-----------------|-------------------|------------|
-| 4 bytes         | 4 bytes           | 4 bytes    |
+|`Compressed_Size`|`Decompressed_Size`|`[XXH64_Checksum]`|`[SHA512-256_Checksum]`|
+|-----------------|-------------------|------------------|-----------------------|
+| 4 bytes         | 4 bytes           | 4 bytes          | 32 bytes              |
 
 __`Compressed_Size`__
 
@@ -108,9 +113,14 @@ __`Decompressed_Size`__
 
 The size of the decompressed data contained in the frame.  For skippable or otherwise empty frames, this value is 0.
 
-__`Checksum`__
+__`XXH64_Checksum`__
+
+Only present if `XXH64_Checksum_Flag` is set in the `Seek_Table_Descriptor`.  Value : the least significant 32 bits of the XXH64 digest of the uncompressed data, stored in little-endian format.
+
+__`SHA512-256_Checksum`__
 
-Only present if `Checksum_Flag` is set in the `Seek_Table_Descriptor`.  Value : the least significant 32 bits of the XXH64 digest of the uncompressed data, stored in little-endian format.
+Only present if `SHA512-256_Checksum_Flag` is set in the `Seek_Table_Descriptor`.  Value : the 256 bits of the SHA-512/256 digest of the uncompressed data, stored in little-endian format.
 
 ## Version Changes
 - 0.1.0: initial version
+- 0.2.0: add cryptographic content hash