gcs-obj-vers.log

Query: protoPayload.request.metadata.versioning.enabled=true
Enable Object Versioning:
{
  "protoPayload": {
    "@type": "type.googleapis.com/google.cloud.audit.AuditLog",
    "status": {},
    "authenticationInfo": {
      "principalEmail": "terraform@anon-terraform-prod.iam.gserviceaccount.com",
      "serviceAccountKeyName": "//iam.googleapis.com/projects/anon-terraform-prod/serviceAccounts/terraform@anon-terraform-prod.iam.gserviceaccount.com/keys/cbf7d9769c83853e97a2dc08240872c54de991f2"
    },
    "requestMetadata": {
      "callerIp": "2600::1",
      "callerSuppliedUserAgent": "apitools Python/3.6.8 gsutil/4.61 (darwin) analytics/enabled interactive/True command/versioning google-cloud-sdk/339.0.0,gzip(gfe)",
      "requestAttributes": {
        "time": "2021-08-19T17:51:31.844550548Z",
        "auth": {}
      },
      "destinationAttributes": {}
    },
    "serviceName": "storage.googleapis.com",
    "methodName": "storage.buckets.update",
    "authorizationInfo": [
      {
        "resource": "projects/_/buckets/s3.anon.net",
        "permission": "storage.buckets.update",
        "granted": true,
        "resourceAttributes": {}
      }
    ],
    "resourceName": "projects/_/buckets/s3.anon.net",
    "request": {
      "bucket": "s3.anon.net",
      "metadata": {
        "versioning": {
          "enabled": true
        },
        "name": "s3.anon.net",
        "id": "s3.anon.net"
      },
      "projection": "NO_ACL"
    },
    "response": {
      "etag": "CAM=",
      "metageneration": "3",
      "storageClass": "STANDARD",
      "updated": "2021-08-19T17:51:31.954Z",
      "timeCreated": "2018-07-20T00:46:43.093Z",
      "id": "s3.anon.net",
      "versioning": {
        "enabled": true
      },
      "iamConfiguration": {
        "uniformBucketLevelAccess": {}
      },
      "projectNumber": "417127842024",
      "name": "s3.anon.net",
      "locationType": "multi-region",
      "location": "US"
    },
    "resourceLocation": {
      "currentLocations": [
        "us"
      ]
    }
  },
  "insertId": "slfn9ddc3sc",
  "resource": {
    "type": "gcs_bucket",
    "labels": {
      "location": "us",
      "bucket_name": "s3.anon.net",
      "project_id": "anon-logs-prod"
    }
  },
  "timestamp": "2021-08-19T17:51:31.834523489Z",
  "severity": "NOTICE",
  "logName": "projects/anon-logs-prod/logs/cloudaudit.googleapis.com%2Factivity",
  "receiveTimestamp": "2021-08-19T17:51:32.286951460Z"
}

Disable Object Versioning:
{
  "protoPayload": {
    "@type": "type.googleapis.com/google.cloud.audit.AuditLog",
    "status": {},
    "authenticationInfo": {
      "principalEmail": "terraform@anon-terraform-prod.iam.gserviceaccount.com",
      "serviceAccountKeyName": "//iam.googleapis.com/projects/anon-terraform-prod/serviceAccounts/terraform@anon-terraform-prod.iam.gserviceaccount.com/keys/cbf7d9769c83853e97a2dc08240872c54de991f2"
    },
    "requestMetadata": {
      "callerIp": "2600::1",
      "callerSuppliedUserAgent": "apitools Python/3.6.8 gsutil/4.61 (darwin) analytics/enabled interactive/True command/versioning google-cloud-sdk/339.0.0,gzip(gfe)",
      "requestAttributes": {
        "time": "2021-08-19T17:50:00.957623571Z",
        "auth": {}
      },
      "destinationAttributes": {}
    },
    "serviceName": "storage.googleapis.com",
    "methodName": "storage.buckets.update",
    "authorizationInfo": [
      {
        "resource": "projects/_/buckets/s3.anon.net",
        "permission": "storage.buckets.update",
        "granted": true,
        "resourceAttributes": {}
      }
    ],
    "resourceName": "projects/_/buckets/s3.anon.net",
    "request": {
      "bucket": "s3.anon.net",
      "projection": "NO_ACL",
      "metadata": {
        "versioning": {},
        "name": "s3.anon.net",
        "id": "s3.anon.net"
      }
    },
    "response": {
      "id": "s3.anon.net",
      "metageneration": "2",
      "versioning": {},
      "locationType": "multi-region",
      "iamConfiguration": {
        "uniformBucketLevelAccess": {}
      },
      "updated": "2021-08-19T17:50:01.276Z",
      "timeCreated": "2018-07-20T00:46:43.093Z",
      "storageClass": "STANDARD",
      "location": "US",
      "etag": "CAI=",
      "projectNumber": "417127842024",
      "name": "s3.anon.net"
    },
    "resourceLocation": {
      "currentLocations": [
        "us"
      ]
    }
  },
  "insertId": "m746z2e4p8ig",
  "resource": {
    "type": "gcs_bucket",
    "labels": {
      "project_id": "anon-logs-prod",
      "bucket_name": "s3.anon.net",
      "location": "us"
    }
  },
  "timestamp": "2021-08-19T17:50:00.944333981Z",
  "severity": "NOTICE",
  "logName": "projects/anon-logs-prod/logs/cloudaudit.googleapis.com%2Factivity",
  "receiveTimestamp": "2021-08-19T17:50:01.746774237Z"
}