Add an author box to an author archive in a Genesis child theme. Place this in your functions.php for your child theme.

s25_author_box.php

<?php 
/**
 *
 * Add author box before the loop on an author archive. 
 * Grabs the ID from the query. On an author archive, this the author ID.
 * get_the_author_meta() is used to retrieve the various meta: user_nicename, description, etc.
 * http://codex.wordpress.org/Function_Reference/get_the_author_meta
 *
 */

add_action('genesis_before_loop', 's25_custom_author_box_archive');
function s25_custom_author_box_archive() {
  if ( is_author() ) {
    $auth_id = get_queried_object()->ID; //Get the author ID from the query
    echo '<div class="author-box">';
      echo get_avatar( $auth_id, 100 );
      echo '<h2>' . get_the_author_meta( 'user_nicename', $auth_id ) . '</h2>'; 
      echo '<p>' . get_the_author_meta( 'description', $auth_id ) . '</p>';
    echo '</div>';
  }
}