SQL & PL/SQL

I'm try to build a procedure that can take an XMLType as a parameter. What I would like to do be able to extract both the node names and the string values from each tag of the XML and put them into basically a key --> value associative array.

Ex:
<envelope>
<node1>value1</node1>
<node2>value2</node2>
</envelope>

Would be put into an array structured like: array['node1'] = 'value1', array['node2'] = 'value2', etc.

I'm not entirely sure how I go about looping through the XMLType and extracting each node name and its value. I'm not worried about repeating tag names.. I know that will not be an issue in any of the XMLTypes that I'm using.

Would anyone be able to offer any suggestions? If not how to go about doing exactly that, then at least some insight as to how I can loop through and extract nodes and/or values without specifying the specific XPaths?

Thanks in advance!