eliminar marcas en Google Maps V3

Referencia para eliminar Markers en Google Maps V3

https://developers.google.com/maps/documentation/javascript/examples/marker-remove?hl=es

Mapas Google renderizado de imagen

<script src="http://maps.googleapis.com/maps/api/js?sensor=false">/*referenciamos el Api de los mapas*/</script>
 <script type="text/javascript">
$(document).on("ready", function(){                                                                 
        var myLatLng = {lat:latitudv, lng:longitudv}                                            
        var myLatLng2 = {lat:latitudpop, lng:longitudpop}                                  
        var imagepop = 'image/verde.png';                                                            
        var imageuser ='image/icono_gps.gif';                                                       
                                                                                                                            
        var mapOptions = {                                                                                    
            zoom: 16,                                                                                                
            center: new google.maps.LatLng(latitudv, longitudv),                           
            mapTypeId:google.maps.MapTypeId.ROADMAP                                
        };                                                                                                                 
        mapa = new google.maps.Map($("#map-canvas")[0], mapOptions);        
                                                                                                                            
        var marker = new google.maps.Marker({ /*  Icono Gif con efecto  */      
            position: myLatLng,                                                                               
            map: mapa,                                                                                             
            animation: google.maps.Animation.DROP,                                           
            icon: imageuser,                                                                                     
            optimized:false   /*  desactivamos la norma de renderizado para que  
tome el efecto deseado*/                                                                                   
        });                                                                                                              
        var marker = new google.maps.Marker({   /*  Icono normal  */              
            position: myLatLng2,                                                                            
            map: mapa,                                                                                            
             animation: google.maps.Animation.DROP,                                         
            icon: imagepop                                                                                      
        });                                                                                                              
           marker.setMap(mapa);                                                                           
    });                                                                                                                  
</script>