The rights, powers, authorities, and remedies provided for in this article shall be cumulative and in addition to other existing rights, powers, authorities, and remedies. Any executor, trustee, or other fiduciary or attorney-in-fact having express or implied powers to execute leases for the production of oil, gas, or other minerals may freely do so under the provisions of the instrument appointing them without the necessity of proceeding as provided in this article. The powers of trustees appointed under this article to execute leases includes the power, under proper order of court, to enter into, execute, and deliver valid contracts and option agreements relating to the future execution or delivery of such leases and contracts granting exclusive rights to enter such lands to make geophysical and geological surveys, explorations, and tests including core drilling.L. 55: p. 730, § 9. CRS 53: § 118-14-9. C.R.S. 1963: § 118-14-9.