diff --git a/pylot/RELEASE-VERSION b/pylot/RELEASE-VERSION
index 33a2193d..12afd1d6 100644
--- a/pylot/RELEASE-VERSION
+++ b/pylot/RELEASE-VERSION
@@ -1 +1 @@
-98f7-dirty
+97de-dirty
diff --git a/pylot/core/util/utils.py b/pylot/core/util/utils.py
index 6de1e8e4..239f3c8d 100644
--- a/pylot/core/util/utils.py
+++ b/pylot/core/util/utils.py
@@ -977,7 +977,7 @@ def check4rotated(data, metadata=None, verbosity=1):
                 dip = blockette_.dip
                 azimut = blockette_.azimuth
                 break
-            if dip is None or azimut is None:
+            if (dip is None or azimut is None) or (dip == 0 and azimut == 0):
                 error_msg = 'Dip and azimuth not available for trace_id {}'.format(trace_id)
                 raise ValueError(error_msg)
             return dip, azimut