#WordPress use page template for archive with WP_Query

blog.php

<?php
/**
 * Template Name: Blog Archive
 */

get_header(); ?>

	<div id="primary" class="site-content">
		<div id="content" role="main">
			
		<?php
		$paged = (int) get_query_var('paged');
		$args = array(
			'posts_per_page' => 10,
			'paged' => $paged,
			'orderby' => 'post_date',
			'order' => 'DESC',
			'post_type' => 'post',
			'post_status' => 'publish'
		);
		$myquery = new WP_Query($args);
		
		if ( $myquery->have_posts() ) :
			?>
			<header class="archive-header">
				<h1 class="archive-title">ブログアーカイブ</h1>
			</header><!-- .archive-header -->
			<?php
			
			while ( $myquery->have_posts() ) :
				$myquery->the_post();
				
				get_template_part( 'content', get_post_format() );
				
			endwhile;
			
			if ( $myquery->max_num_pages > 1 ) :
			?>
			<nav class="navigation" role="navigation">
				<div class="nav-previous alignleft"><?php echo get_next_posts_link( __( '<span class="meta-nav">&larr;</span> Older posts', 'twentytwelve' ), $myquery->max_num_pages ); ?></div>
				<div class="nav-next alignright"><?php echo get_previous_posts_link( __( 'Newer posts <span class="meta-nav">&rarr;</span>', 'twentytwelve' ) ); ?></div>
			</nav>
			<?php 
			endif;
			?>
			
		<?php else : ?>
			<?php get_template_part( 'content', 'none' ); ?>
		<?php endif; ?>
			
		
		<?php
		// reset post data
		wp_reset_postdata();
		?>

		</div><!-- #content -->
	</div><!-- #primary -->

<?php get_sidebar(); ?>
<?php get_footer(); ?>