OPatch detects your platform as 46 while this patch 6702510 supports platforms:

The Issue with applying the Opatch 6702510 as a process of upgrading the AS 10g 10.1.3.0 to 10.1.3.4

The Issue:
Creating log file "/oracle/PRODN/apps/tech_st/10.1.3/.patch_storage/6702510/Apply_6702510_07-13-2009_10-52-56.log"
Invoking fuser to check for active processes.
OPatch detects your platform as 46 while this patch 6702510 supports platforms:
0 (Generic Platform)
This patch is not suitable for this operating system.
Please contact support for the correct patch.
ERROR: OPatch failed during pre-reqs check.

The Fix:
[oracle@prod 6702510]$ export OPATCH_PLATFORM_ID=0
[oracle@prod 6702510]$ opatch apply
Oracle Interim Patch Installer version 1.0.0.0.56
Copyright (c) 2006 Oracle Corporation. All Rights Reserved..
We recommend you refer to the OPatch documentation underOPatch/docs
for usage reference. We also recommend usingthe latest OPatch version.
For the latest OPatch version
and other support related issues, please refer to document293369.1 which is viewable from metalink.oracle.com
Oracle Home : /oracle/PRODN/apps/tech_st/10.1.3
Oracle Home Inventory : /oracle/PRODN/apps/tech_st/10.1.3/inventoryCentral Inventory : /oracle/oraInventory
from : /etc/oraInst.locOUI location : /oracle/PRODN/apps/tech_st/10.1.3/ouiOUI
shared library : /oracle/PRODN/apps/tech_st/10.1.3/oui/lib/linux/liboraInstaller.so
Java location : /oracle/PRODN/apps/tech_st/10.1.3/jre/1.4.2/bin/java
Log file location : /oracle/PRODN/apps/tech_st/10.1.3/.patch_storage//*.log
Creating log file "/oracle/PRODN/apps/tech_st/10.1.3/.patch_storage/6702510/Apply_6702510_07-13-2009_10-53-29.log"
Invoking fuser to check for active processes.
Backing up comps.xml ...
OPatch detected non-cluster Oracle Home from the inventory and will patch the local system only.
Please shut down Oracle instances running out of this ORACLE_HOME(Oracle Home = /oracle/PRODN/apps/tech_st/10.1.3)Is this system ready for updating?Please respond YN >YApplying patch 6702510...
Patching jar files...

Inventory is good and does not have any dangling patches.
Updating inventory...
Verifying patch...
Verifying that patch ID is in Oracle Home inventory.
Verifying jar files.
OPATCH_VERIFY_OK: Patch has been applied.
Backing up comps.xml ...
OPatch succeeded.