Fitzhugh T. Lee Sharon F. Diehl 1978 <p>Physical properties, including density and strength, of the Lucerne Granite (Wing, 1958) vary because of inhomogeneities caused by fracturing and differences in texture. Two granitic facies were found: a coarse-grained variety in the southern part of the body and near the edges of the pluton and a medium-grained porphyritic variety in the central and northern sections. Point-load strength tests indicate that the medium-grained porphyritic granite is stronger than the coarse-grained porphyritic or non-porphyritic granite. Results of bulk and grain density tests suggest that rock strength in the weaker granite samples is controlled by microfractures.</p><p>In the pluton, joint trends changed from a scattered pattern in the north to a preferred orientation in the south. Because it has a simple joint pattern and is homogeneous in texture, the southern part of the Lucerne Granite is a more suitable area for excavation and fluid storage than the northern section.</p> application/pdf 10.3133/ofr78862 en U.S. Geological Survey Reconnaissance geotechnical study of the Lucerne Granite, Maine reports