diff --git a/src/collectl2pcp/collectl2pcp.c b/src/collectl2pcp/collectl2pcp.c
index c9755af..4bf6b58 100644
--- a/src/collectl2pcp/collectl2pcp.c
+++ b/src/collectl2pcp/collectl2pcp.c
@@ -248,12 +248,23 @@ main(int argc, char *argv[])
 	    fields_free(f);
 	}
 
-	/* final flush for this file */
+	/* final flush for this collectl input log */
 	if ((sts = timestamp_flush()) < 0) {
 	    fprintf(stderr, "Error: failed to write final timestamp: %s\n", pmiErrStr(sts));
 	    exit(1);
 	}
 
+	if (filenum < nfilelist-1) {
+	    /*
+	     * End of this collectl input log and there's more input files,
+	     * emit a <mark> to signify a temporal gap since the output PCP
+	     * archive is effectively a merged archive.
+	     */
+	    if (vflag)
+		fprintf(stderr, "End of collectl input file '%s', <mark> record emitted\n", infile);
+	    pmiPutMark();
+	}
+
 	if (gzipped)
 	    pclose(fp);
 	else
diff --git a/src/include/pcp/import.h b/src/include/pcp/import.h
index e535796..5e6940f 100644
--- a/src/include/pcp/import.h
+++ b/src/include/pcp/import.h
@@ -42,6 +42,7 @@ PMI_CALL extern int pmiGetHandle(const char *, const char *);
 PMI_CALL extern int pmiPutValueHandle(int, const char *);
 PMI_CALL extern int pmiWrite(int, int);
 PMI_CALL extern int pmiPutResult(const pmResult *);
+PMI_CALL extern int pmiPutMark(void);
 
 /* helper routines */
 PMI_CALL extern pmID pmiID(int, int, int);
diff --git a/src/libpcp_import/src/exports b/src/libpcp_import/src/exports
index a544262..d484e6e 100644
--- a/src/libpcp_import/src/exports
+++ b/src/libpcp_import/src/exports
@@ -1,4 +1,4 @@
-PCP_IMPORT_1.0 {
+PCP_IMPORT_1.1 {
   global:
     pmiStart;
     pmiSetHostname;
@@ -23,6 +23,7 @@ PCP_IMPORT_1.0 {
     pmiPutValueHandle;
 
     pmiWrite;
+    pmiPutMark;
 
   local: *;
 };
diff --git a/src/libpcp_import/src/import.c b/src/libpcp_import/src/import.c
index 71b8c7f..2ea08af 100644
--- a/src/libpcp_import/src/import.c
+++ b/src/libpcp_import/src/import.c
@@ -724,3 +724,40 @@ pmiPutResult(const pmResult *result)
 
     return  current->last_sts = _pmi_put_result(current, current->result);
 }
+
+int
+pmiPutMark(void)
+{
+    __pmLogCtl *lcp;
+    struct {
+	__pmPDU		hdr;
+	__pmTimeval	timestamp;	/* when returned */
+	int		numpmid;	/* zero PMIDs to follow */
+	__pmPDU		tail;
+    } mark;
+
+    if (current == NULL)
+	return PM_ERR_NOCONTEXT;
+
+    if (current->last_stamp.tv_sec == 0 && current->last_stamp.tv_usec == 0)
+	/* no earlier pmResult, no point adding a mark record */
+	return 0;
+    lcp = &current->logctl;
+
+    mark.hdr = htonl((int)sizeof(mark));
+    mark.tail = mark.hdr;
+    mark.timestamp.tv_sec = current->last_stamp.tv_sec;
+    mark.timestamp.tv_usec = current->last_stamp.tv_usec + 1000;	/* + 1msec */
+    if (mark.timestamp.tv_usec > 1000000) {
+	mark.timestamp.tv_usec -= 1000000;
+	mark.timestamp.tv_sec++;
+    }
+    mark.timestamp.tv_sec = htonl(mark.timestamp.tv_sec);
+    mark.timestamp.tv_usec = htonl(mark.timestamp.tv_usec);
+    mark.numpmid = htonl(0);
+
+    if (fwrite(&mark, 1, sizeof(mark), lcp->l_mfp) != sizeof(mark))
+	return -oserror();
+    else
+	return 0;
+}